AGRICULTURE TOPIC BY TOPIC REVISION QUESTIONS AND ANSWERS
Introduction to Agriculture
Definition of Agriculture
- Agriculture is the science and art of cultivation of crops and rearing of livestock.
- As a science, it involves experimentation and application of scientific knowledge in such areas as;
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- Soil analysis,
- Control of pests and diseases,
- Farm machinery and structures,
- Crop and livestock breeding.
- As an art, it involves the use of learned skills in;
- Tilling the land,
- Harvesting of crops,
- Feeding and handling of livestock
Branches of Agriculture
Crop Farming (Arable Farming)
- The practice of growing crops on cultivated land.
It is subdivided into:
- Field crops Cultivation:
- maize, beans, potatoes, coffee, tea, cotton to name but a few.
- It involves the growing of perishable crops which have high value.
- It is further subdivided into:
- Floriculture – the growing of flowers.
- Olericulture – the growing of vegetables.
- Pomoculture – the growing of fruits.
- This branch deals with the rearing of livestock for various products.
It is further subdivided into:
- Pastoralism: This is the rearing of mammalian livestock such as cattle, sheep, goats, rabbits, pigs and camels.
- Fish Farming (Aquaculture): This is the practice of rearing fish and other aquatic organisms , in ponds.
- Bee Keeping (Apiculture): This involves the rearing of bees in structures known as beehives.
- Poultry Keeping: This is the keeping of domesticated birds.
- It deals with the allocation of scarce resources (land, labour, capital and management) for agricultural production.
- This branch of agriculture deals with the use and maintenance of farm tools, machinery and structures.
- A farming system is the organization of the various enterprises in a farm.
It is determined by the following factors:
- Resources available (land, labour, capital and management).
- Skills of the farmer.
- Environmental factors such as climate, soil type and topography.
- Government policy.
- Farmer’s choice and preference.
- Enterprise requirement.
- Social-cultural factors.
The following are systems of farming:
- It is a system where a large piece of land with low investment of resources per unit area is carried out.
- It is cheap.
- Does not require high level of management.
- Requires less labour.
- Low profit per unit area.
- Cannot be practiced where land is limited.
- Low output per unit area.
- The land is under-utilized,
- This system utilizes the factors of production to the maximum and involves high level of management.
- Maximum utilization of the resources.
- Can be practiced even where land is a limiting factor.
- Results in high yields.
- Labour intensive.
- High capital investment is required.
- Requires high level of management.
- Can lead to high loses in case of poor management.
Large Scale Farming
- Refers to the farming practice under large areas of land over 20 hectares.
- It is used mainly for commercial purposes.
- The system is highly mechanized.
- Results in high yields.
- Due to economics of scale high profit is realized.
- Lack of diversification may lead to total failure in case of unfavorable conditions.
- High level of management is required.
- Heavy capital investment.
- Requires skilled and qualified manpower.
Small Scale Farming
- Refers to farming carried out on a small area of land less than 5 hectares.
- Family or casual labour can be engaged during the peak periods.
- Most of the Kenyan farmers are small scale due to unavailability of farmland.
- Requires low capital investment.
- Possible where land is a limiting factor.
- Does not require high management level unless under intensive system.
- Uneconomical 10 mechanize due to small size.
- Low production.
- Provides limited employment.
- Labour intensive.
- Difficult to specialize.
Methods of Farming
- A method of farming is an established way of carrying out farming activities.
- The following are the common methods of farming:
- It is the practice of growing crops and keeping of livestock on the same land.
- Its common in high potential areas.
- Mutual benefit between crops and livestock.
- Crops supply feed for animals while animals supply manure for crops.
- Acts as an insurance against total loss by the farmer.
- The farmer is assured of an income throughout the year.
- There is maximum utilization of the resources.
- Animals can be used in the farm activities particularly draught animals.
- Ensures proper utilization of labour and land throughout the year.
- High initial capital.
- Lack of specialization.
- Land can be a limiting factor if both enterprises are to be raised.
- Requires high level of management for both enterprises.
- This is the practice of livestock rearing whereby animals are moved from one place to another in search of water and pastures.
- It is practiced in the arid and semi-arid areas where in most cases beef animals are kept.
Nomadic pastoralism is gradually changing to ranching with the introduction of:
- Improved pasture species, improved livestock breeds and supplementary feeding.
- Efficient disease and parasite control measures.
- Improved infra-structure such as roads, water supply, cattle dipping facilities.
- Extension services.
- Serves as the backbone of beef industry in Kenya.
- Proper way of utilizing the arid and semi arid areas.
- Source of income to the pastoral communities.
- It encourages the spread of livestock pests and diseases due to communal watering points, grazing and dipping facilities.
- There is a tendency to increased soil erosion and land degradation.
- Source of conflicts and ethnic tension among the nomadic communities for the control of good pastures and water.
- Difficult to control breeding and breeding diseases.
- High rate of inbreeding leading to poor quality livestock.
- Low production of milk, meat, hides and skins due to wastage of energy in traveling from one place to another in search of pastures and water.
- High death rates as a result of walking for long distances.
- It is a traditional method of cultivating a piece of land until the soil is exhausted and crop yields decline.
- The land is abandoned and the farmer shifts to a new field as the previous land is left fallow to regain its fertility.
- Land is allowed to rest and regain its fertility.
- No build up of pests and diseases.
- Soil structure is restored.
- The cost of production is low since inorganic fertilizers and pesticides are not used.
- Crop produce are chemical free.
- Not practical where land is a limiting factor.
- Farm planning and acquisition of credits for land development is ‘not possible.
- It is a cumbersome method due to constant movement.
- Lack of soil conservation measures
- Not possible to grow perennial crops.
- Low output per unit area due to poor farming methods.
- Where fire is used to clear the land organic matter is destroyed.
- It is a fanning method where crops are grown and livestock reared without the use of agrochemicals.
- It is a method of farming which has been adopted to reduce the long term effect of the agro-chemicals on crops which may eventually end up in man and livestock.
- Agro-chemicals are also expensive thus organic farming reduces the cost of production. Organically produced goods fetch high market prices.
- Cheap and cost effective.
- Make use of the locally available materials
- Useful in improving the soil structures.
- No side effects from the crops and livestock products.
- No environmental pollution.
- This is the practice of integrating trees and crops on the same piece of land.
- With land resources becoming more scarce, agroforestry is becoming more important.
Examples of common agroforestry trees and shrubs include:
- Cajanus cajan
- Grevillea robusta
- Sesbania sesban
- Calliandra calothyrsus
- Casuarina equisetifolia
- Leucaena leucocephala
Trees selected for agroforestry should have the following characteristics:
- Able to grow fast.
- Deep roots to minimize competition for nutrients.
- Should be preferably leguminous.
- Trees reduce soil erosion in a given area.
- Leguminous trees add nitrates into the soil thus improving the soil fertility.
- Some trees can be used as livestock fodder to provide a high level of proteins.
- They are important sources of wood fuel and timber.
- There is maximum utilization of land.
Importance of Agriculture to the Economy of Kenya
- Provides food to the population to meet nutritional requirements and to enable man to engage in other activities of farming.
- Provides employment. This for example can be direct as a labourer in the farm, tea plucker or indirect for example, working in agricultural based industries.
- Source of raw materials for industries for example cotton lint for textile industry.
- Provides foreign exchange – through exporting agricultural produce.
- Provides market for industrial goods agriculture is a consumer of the finished goods from agro-based industries.
- Source of income – farmers as well as the government get revenue from the sale of agricultural produce and tax payment.
Factors Influencing Agriculture
Agricultural production is influenced by external factors:
- Human factors
- Biotic factors
- Climatic factors
- Edaphic factors.
These are human characteristics which affect the way decisions are made and operations carried out.
- Level of education and technology:
- Technological ad van cements .
- Human health/HIV-AIDS:
- These affect the strength, the vigour, vision and the determination
- HIV/AIDS is the biggest threat to human health today and has long
lasting effects on agriculture, such as;
- Shortage of farm labour.
- Loss of family support.
- Low living standards leading to despondency and hopelessness.
- Increased criminal activities.
- More time spent by the Government and NGO’s in Carring for the sick.
- Stability in the countries’ economy affect agricultural production.
- Government Policy:
- These are governmental laws which have been enacted to protect farmers, land and livestock.
- Food policy
- Policies on control of livestock parasites and diseases.
- Policies on marketing of both local and export products and others.
- Transport and communication:
- For agricultural goods to move from the farm to the consumers.
- Cultural practices and religious beliefs:
- These activities hinder important changes in a society that may bring agricultural development.
- Market forces:
- Demand and supply forces which affect prices of commodities in a free market.
These are living organisms which affect agricultural production.
- Pests – Destructive organisms which destroy crops.
- Parasites – These are invertebrates which live in or on other living organisms.
- Decomposers – Organisms which act on plants and animal tissues to form
- Pathogens – Micro-organisms which cause diseases.
- Predators – Animals that kill and feed on other animals.
- Pollinators – They transfer pollen grains from the stamens to the pistil of a flower.
- Nitrogen fixing bacteria -They are micro-organisms which convert atmospheric nitrogen to nitrates ready for use by the plants.
Climatic Factors(weather elements).
- Relative humidity
Weather – Atmospheric conditions of a place at a given time period.
Climate – weather conditions of a place observed and recorded for a period of 30-40 years.
- Which is necessary for the life process in plants and animals.
- Which makes the plant turgid hence provides support.
- Acts as a solvent for plant nutrients.
- Cools the plant during transpiration.
- Which is used as a raw material in photosynthesis.
When plants lack enough water they respond in different ways as follows:
- By closing the stomata to restrict water loss.
- Hastens maturity.
- Some will roll their leaves.
Other plants have developed permanent adaptation to water stress such as:
- Growing needle like leaves.
- Develop fleshy leaves for water storage.
- Develop long roots.
- Wilting and death in extreme conditions.
Important Aspects of Rainfall:
- Rainfall reliability;
- This is the dependency on the timing of the onset of the rains.
- Amount of rainfall;
- Quantity of rain that falls in a given area within a given year.
- Rainfall distribution ;
- The number of wet months in a year.
- Rainfall intensity;
- Amount of rainfall that falls in an area within a period of 1
- This is the degree of hotness or coldness of a place measured in degrees Celsius.
- Cardinal range of temperature is the temperature required by plant to grow and thrive well.
- Optimum range of temperatures – the best temperature for the best performance of plants.
Effects of Temperatures on Crop Production:
- Slow the growth rate of crops due to slowed photosynthesis and respiration.
- High incidences of disease infection.
- Improves quality of crops such as tea and pyrethrum.
- Increase evaporation rate leading to
- Hastens the maturity of crops.
- Increase disease and pest infection.
- Improves quality of crops such as pineapples, oranges and pawpaws.
Wind is moving air.
Good effects of wind include:
- Seed dispersal
- Cooling of land
- Pollination in crops
- Brings rain bearing clouds
Negative effects of wind:
- Increases the rate of evaporation of water.
- Causes lodging of cereals and distorts perennial crops.
- Increases evapo-transpiration.
- Spreads diseases and pests.
- Destroys farm structures.
- The amount of water vapour in the air
- Affects the rate of evapo-transpiration.
- Forms dew which supplies soil with moisture under dry conditions.
- High humidity induce rooting in cuttings.
- Increases disease multiplication and spread.
- Provide radiant energy harnessed by green plant for photosynthesis.
Important aspects of light:
- Light intensity ;
- The strength with which light is harnessed by chlorophyll for photosynthesis.
- Light duration;
- The period during which light is available to plants per day.
- Plant response to light duration is known as
- Short-day plants – require less than 12 hours of daylight to flower and
- Long-day plants – require more than 12 hours of daylight to flower and seed.
- Day-neutral plants require 12 hours of daylight to flower and seed.
- Light wavelength;
- This is the distance between two – successive crests of a wavelength.
- It dictates the difference between natural and artificial light.
- Chlorophyll absorbs certain wavelengths of light.
Edaphic Factors Influencing Agriculture
- These are soil factors.
- Soil is the natural material that covers the surface of the earth,
- Made of weathered rock particles and decomposed animal and plant tissues, and on which plants grow.
Importance of Soil
- Provides anchorage to the plants by holding their roots firmly.
- Provides plants with mineral salts/ nutrients which are necessary for their growth.
- Provide the plants with water.
- Contains oxygen necessary for respiration of the plants and soil micro-organisms.
- Soil is formed through weathering process.
- Weathering is the breakdown and alteration of the parent rock near the surface of the earth to a stable substance.
- Weathering process is a combination of disintegration (breakdown) and synthesis (build up) process.
- Weathering process is continuous.
Types of Weathering
- Physical weathering
- Chemical weathering
- Biological weathering
Agents of Weathering
Physical Agents of Weathering
- Include wind, water, moving ice and temperature.
- Wind – carry materials which hit against each other to break into fragments.
- Water – intensity of rainfall causes breakdown of rock.
- Moving ice – has grinding effects which tear off rock particles.
- Extreme temperature cause rocks to expand and contract suddenly peeling off their surface.
- Affects the chemical composition and structure of the rock.
- Involves processes such as ;
- The process by which soluble minerals in the rocks absorb water and expand weakening the rock thus leading to disintegration.
- The process whereby water dissolves soluble minerals in the rock weakening it.
- The reaction of rock minerals with oxygen to form oxides which break easily.
- The process whereby carbonic acids formed when rain water dissolves carbon dioxide,
- It reacts with calcium carbonates in limestone causing it to disintegrate.
This involves the action of living organisms, plants and animals on the rocks.
- Burrowing animals, for example, termites and moles bring soil particles to the surface exposing them to other agents of weathering.
- Big animals like, elephants, buffaloes, camels and cattle exert a lot of pressure on the rocks as they step on them due to their heavy weights causing the rocks to disintegrate.
- Earthworms take part in the decomposition of plant matter with the soil particles.
- Man’s activities like, mining and quarrying expose rocks to the surface during excavation. These activities breakdown large rocks into smaller rock particles.
- Plant roots force their way through the cracks in the rocks thus widening and splitting them.
- Humic acids formed when plant tissues decompose react with the rocks weakening them further.
- Plant remains-decompose adding humus into the soil.
Factors influencing soil formation
- Climate- (rainfall, temperature and wind)
- Biotic factors – living organisms.
- Parent material– Nature and properties of the original rock from which the soil is formed.
- Time – length of time during which the soil forming processes have taken
- Topography – influences the movement of disintegrated materials.
- It is the vertical arrangement of different layers of soil from the ground surface to the bedrock.
- These layers are also referred to as horizons.
- The layers show differences in their contents and physical properties such as colour, texture and structure.
- The layers include: organic matter region, top soil, sub-soil, weathered rocks and parent material.
Organic Matter Region
- First layer of the soil found on the surface.
- Made up of leaves and other plant remains at various stages of decomposition.
- Some soil organisms may also be found here.
- Has a dark colour due to the presence of humus.
- Is rich in plant nutrients and well aerated.
- It is a zone of maximum leaching (zone of eluviations)
- It is compact and less aerated.
- It is a zone of accumulation of leached material (zone of aluviation) from the top layers.
- Deep rooted crops have their roots growing up to this region.
- Hard pans normally form in this layer
- It is also called substratum.
- Rocks at various stages of disintegration are found in this zone.
- Most of the materials found in this zone originate from the parent rock.
- It exists as a solid mass which is un-weathered.
- It is the source of the inorganic composition of the soil.
- The water table is on the surface of this rock.
Soils Formed in Situ and Soils Deposited
- Soil formed in the same place and remains there is said to be in situ.
- However, soil can be formed due to deposition of soil particles carried from its original site of formation to another area which is usually in the lower areas of slopes.
- Such soils are said to have been formed through deposition.
|Soil Formed in Situ||Soil Deposited|
|l.Has the colour of the parent rock||1. Has the characteristics of when: it came from.|
|2. Shallower||2. Deeper|
|3. Less rich in plant nutrients||3. Richer in plant nutrients|
|4. Easily eroded||4. Not easily eroded|
|5. Less silty||5. More silty|
|6. Have the same chemical composition||6. Differ in chemical composition from the|
|as that of the underlying parent rock.||underlying parent rock.|
- This is the distance between top soil layer and the bottom soil layer in a profile.
- It dictates root penetration and growth
- Deep soils are more suitable for crop growth since they contain more nutrients.
- Have a larger surface are for root expansion.
- Deep soils facilitate good drainage and aeration.
- Organic Matter – Dead and decaying plants and animal remains
- Living Organisms – Soil organisms and plant roots.
- Micro-organisms (bacteria, protozoa and fungi)
- Invertebrates -termites,
- Earthworms and molluscs.
- Higher animals – rodents and others.
- Inorganic or Mineral Matter
- Formed from the parent materials.
- Supply plant nutrients
- Form the skeleton and framework of the soil.
- Found in the pore spaces of the soil.
- Used for root and organism respiration
- Used for germination of seeds.
- Helps in decomposition of organic matter.
- Regulates soil temperature.
- Regulates the movement of water through capillary action.
- Dissolves mineral salts
- Maintain turgidity in plants.
- Used for germination of seeds
- Used by soil organisms.
- Regulate soil temperature
- Dictates the amount of air in the soil.
Water in the soil exists in three forms namely:
- Superfluous/Gravitational Water
- Found in the large spaces (macro-pores) in the soil particles.
- Held by gravitation forces.
- When the pores are saturated, the soil is said to be waterlogged.
- It moves and may cause leaching.
- Hygroscopic Water
- Water found in thin films on the soil particles.
- Held by strong adhesive forces between water and soil particles.
- Does not move and hence not available for plant use.
- Capillary Water
- Occupy micro-pores in the soil particles.
- Held by cohesive forces between water molecules.
- Moves through capillary action
- Available to plants for use.
- This is the arrangement of soil particles in a soil horizon.
- Types of Soil Structure –
Importance of Soil Structure on Crop Production
Soil Structure Influences
- Soil aeration
- Soil drainage and water holding capacity.
- Plants root penetrability and anchorage.
- Microbial activities in the soil.
- Circulation of gases in the soil.
Farming practices which improve the soil structure are:
- Application of inorganic manure into the soil.
- Tilling the land at the right moisture content.
- Crop rotation.
- Minimum tillage.
- Cover cropping.
- It refers to the relative proportion of the various sizes of the mineral particles of soil.
Importance of Soil Texture on Crop Production;
- Influences soil fertility
- Affects the organic matter content
- Influences the drainage of the soil.
- Influences soil aeration.
- Influences water holding capacity.
- Influences the capillarity or movement of water in the soil.
Soil Textural Classes
- Made up largely of sand particles.
- Have large pore spaces hence poor in water retention.
- Easy to till (light soils).
- Freely draining.
- Low fertility due to leaching of minerals.
- Easily erodible.
- Made up largely of clayey particles.
- Have small pore spaces hence good in moisture retention.
- Difficult to till (heavy soils).
- Poorly ‘drained.
- Expand when wet, crack when dry.
- High capillary.
- Rich in plant nutrients.
- About equal amounts of sand and clay.
- Moderately good in both moisture and air retention.
- Fertile soils.
- This depends on the, mineral composition of the parent rock and the organic matter content.
- Soils containing a lot of iron are brownish, yellowing and reddish in colour.
- Soils with a lot of silica are white.
- Soils with a lot of humus are dark or grey.
- This refers to the acidity or alkalinity of the soil solution/the concentration of hydrogen ions in the soil solution.
- Soil pH is determined by the concentration of hydrogen ions (H+) or the hydroxyl ions (OH) in the soil solution.
- A pH of less than 7 means that the soil is acidic.
- A pH of more than 7 means that the soil is alkaline.
- As the hydroxyl ions (OH) in the soil increase the soil becomes more alkaline.
Influence of Soil pH Crop Growth
- It determines the type of crop to be grown in a particular area.
- Most crops are affected by either very acidic or very basic soil pH.
- Soil pH affects the choice of fertilizers and the availability of nutrients to crops.
- At low pH the concentration of available iron and aluminium in the soil solution may increase to toxic levels, which is harmful to plants.
- Very acidic or low pH inhibit the activity of soil micro-organisms.
Farm Tools and Equipment
- Farm tools and equipment perform specific jobs in the farm.
- They make work easier and more efficient.
- They can be classified according to their uses as follows:
Garden Tools and Equipment
|1.||Panga||Cutting and shallow cultivation, making holes.|
|2.||Jembe/hand hoe||Cultivation, digging, shallow planting holes and trenches.|
|3.||Fork iembe||Cultivation, digging out roots, harvesting of root crops.|
|4.||Rake||Collecting trash, breaking large clods, levelling, removing stones|
|from a seedbed and spreading organic manure.|
|5.||Spade||Scooping and carrying of soil, sand, concrete mixture and|
|6.||Spring balance||Measuring weight.|
|7.||Trowel||Scooping seedlings during transplanting and .digging planting|
|holes for seedlings.|
|8.||Pruning hook||Bending tall branches when pruning.|
|9.||Secateur||Cutting young stems and pruning branches.|
|10. Tape measure||Measuring distances.|
|11. Axe||Cutting big trees and roots and splitting logs of wood.|
|12. Soil auger||Making holes for fencing posts.|
|13. mattock||Digging hard soils|
|14. sprinklers||Overhead irrigation.|
|15. Watering can||Watering plants in nursery bed.|
|16. Wheel barrow||Transportation of soil, fertilizers, farm produce, tools and equipment.|
|17. Levelling board||For levelling a nursery bed.|
|18. Pruning saw||Cutting old wood stems and pruning big branches.|
|19. Hose pipe||For conveying water from a tap to where it is need.|
|20. Knap sack sprayer||Applying agro-chemical by spraying.|
|21. Garden shear||Trimming hedges.|
|22. Pruning knife||Removal of small shoots.|
|23. Meter ruler||Measuring distances.|
|24. Garden fork||Shallow digging.|
Livestock Production Tools and Equipment
|1.||Drenching gun||Administering liquid drugs to animals orally.|
|2.||Bolus gun/dosing gun||Administering solid drugs or tablets to animals orally.|
|3.||Wool Shears||Cutting off wool from sheep.|
|4.||Hypodermic syringe||Administering drugs by injection for example in vaccination.|
|5.||Stirrup (bucket) pump||Application of acaricide by hand spraying.|
|6.||Thermometer||Taking body temperatures of farm animals.|
|7.||Burdizzo||Used in bloodless method of castration.|
|8.||Halter||Rope designed to restrain the animal.|
|9.||Trimming knife||Cutting short the overgrown hooves.|
|Elastrator||Stretching rubber ring during castration, dehorning and docking|
|Iron dehorner||Applies heat on the horn bud to prevent growth of horns.|
|Nose ring||Fixed into the nose of a bull to restrain it.|
|Strip cup||Detecting mastitis in milk products.|
|Trocar and cannula||Relieving a bloated animal of gases particularly ruminants.|
|Hard broom||For scrubbing the floor.|
|Ear notcher||Making ear notches in livestock.|
|Bucket||For holding milk during milking.||~|
|Milk chum||For holding milk after milking.|
|Milk strainer/sieve||Removing foreign particles from milk for example hairs and sediments.|
|Rope||Tying or tethering animals.|
|Milking stool||Used by the milker to sit on while milking.|
|Weighing balance||Weighing milk after milking.|
|Teeth clipper||Removal of canine teeth of piglets soon after birth.|
|Chaff cutter||Cutting fodder into small bits.|
|Dehorning wire||Cutting grown horns.|
Workshop Tools and Equipment
|1.||Spanner||Tightening and loosening nuts and bolts.|
|2.||Pliers||Cutting small wires and thin metal and gripping firmly.|
|3.||Files||Sharpening tools, smoothening or shaping edges of metals,|
|4.||Rasps||Smoothening and shaping of wooden structures.|
|5.||Chisels (wood)||Making grooves in wood.|
|6.||Cold chisel||Cutting and shaping metal.|
|7.||Screw drivers||Driving screws in or out of wood or metal.|
|Cross cut saw||Cutting across the grain of wood.|
|Rip saw||Cutting along the grain of wood.|
|Hack saw Bow saw||Cutting metals.|
|Tenonlback saw||Cutting branches of trees.|
|Coping saw||Cutting Joints on wood and fine sawing.|
|Compass/keyhole saw||Cutting curves on thin wood.|
|Cutting either along or across the grain of wood especially|
|when cutting key holes.|
|9.||Tin snip||Cutting metal sheets.|
|10.||Braces and bits.||Boring holes in wood.||,|
|11.||Drill and bits||Boring holes in metal work and woodwork.||=|
|Claw hammer||Driving in, removing and straightening nails.|
|Ball pein||Driving in nails, rivets and straightening metal. Also used|
|on cold chisel|
|13.||Mallet||Hammering or hitting wood chisel.|
|14.||Jack plane||Fine finishing of wood.|
|15.||Scrappers/spokeshave||Smoothening curved surfaces of wood such as handles of|
|Metre ruler||Measuring short length -.|
|Measuring length angles and to ascertain squareness.|
|17.||Marking gauge||Marking parallel lines to the edge of wood.|
|18.||Fencing pliers||Cutting wires, hammering staples when fencing.|
|19.||Vice and clamps||Firmly holding pieces of work together.|
|20.||Spirit level||Measuring horizontal or vertical levels.|
|2l.||Soldering gun||Melting soldering rods when repairing or fabricating metal|
|22.||Wire brush||Brushing rough surfaces.|
|23.||Divider||Marking and laying out.|
|24.||Centre punch||Marking the point of drilling.|
|25.||Paint brush||Applying paint on surfaces.|
|26.||Sledge hammer||Ramming hardware, breaking stones.|
|27.||Wire strainer||Tightening wires during fencing.|
|28.||Riveting machine||Fix rivets when joining pieces of metal.|
|29.||Claw bar||Removing long nails from wood, straining fencing wires and|
|digging fencing holes.|
Plumbing and Masonry Tools
|l.||Pipe wrench||Holding, tightening and loosing metallic pipes.|
|2.||Pipe cutter||Cutting PVC pipes.|
|3.||Levelling rod||Levelling the floor during construction.|
|4.||Mason’s trowel||Placing mortar between construction stones and bricks.|
|5.||Wood float||Create a level surface on walls and floors.|
|6.||Mason’s square||Ascertain verticalness.|
|7.||Plumb bob||Spreading screed over floors and walls.|
|8.||Shovel||Mixing and scooping concrete or mortar, measuring cement.|
Care and Maintenance of Tools and Equipment
Reasons for Maintenance
- To increase durability.
- To increase efficiency.
- Reduce costs of replacement.
- For safety of the user/avoid accidents.
- Avoid damage to the tool.
- Use tools for the right work.
- Proper handling when using tools or equipment.
- Clean and oil tools after work.
- Keep tools in there right place.
- Replace and repair worn-out parts
- Sharpen cutting or digging edges
- Grease moving parts to reduce friction
- Use safety devices in the workshop to reduce accidents and breakages
CROP PRODUCTION 1
- A piece of land which is prepared is known as seedbed.
- A seedbed is a piece of land that is prepared ready to receive planting materials.
Reasons for Seedbed Preparation;
- To enable water to infiltrate.
- To kill weeds
- To improve soil aeration.
- To destroy pests and diseases.
- To incorporate organic matter in the soil.
- For easy planting.
- To facilitate root penetration.
Operations in Land Preparation
- Clearing of land is necessary when:
- Opening up a virgin land.
- A stalk growing crop was previously plan
- There is long interval between primary and secondary cultivation.
- Land was left fallow for a long time.
- Tree felling and removal of stumps and roots.
- Use of chemicals.
Note: Burning should be avoided where possible since it;
- Leads to loss of organic matter,
- Kills soil organisms
- Destroys soil structure and plant nutrients.
- This is the initial breaking of land.
- It is done early before the onset of the rains to:
- Give time for soil organisms to act on organic matter.
- Allow gaseous exchange to take place, thus carbon dioxide diffuses out of the soil while oxygen enters into the soil.
- Allow other operations to take place in time.
Reasons for primary cultivation:
- Remove weeds.
- Burry organic matter.
- Open up soil for infiltration of water and air.
- Expose pests and disease causing organisms.
- Soften the soil for easy planting.
Operations in primary cultivation
- Hand digging ;
Use of hand tools ;
- Mechanical cultivation ;
Use of mouldboard ploughs;
- Disc ploughs,
- Chisel ploughs,
- Use of Ox–Ploughs ;
Which can be drawn by;
Depth of Cultivation
- The type of crop to be planted/size of seed.
- The implements available.
- The type of soil.
Choice of Implement
- The condition of land.
- The type of tilth required/type of crop.
- Depth of cultivation.
- These are refinement practices on the seedbed that follow primary cultivation.
- It is also known as harrowing.
Reasons for secondary Tillage:
- To remove the germinating weeds.
- To break soil clods to produce required tilth.
- To level the seedbed for uniform planting.
- To incorporate organic matter/manure into the soil.
Factors determining number of secondary cultivation:
- Soil moisture content.
- Size of the planting materials.
- Condition of the soil after primary cultivation.
- Slope of the land.
- Ridging ;
- The process of digging soil on a continuous line and heaping on one side to produce a furrow and a bund (ridge).
- It is important for root crops, to allow root expansion and for soil and water conservation.
- It is the compaction of the soil to produce a firm surface which increases seed-soil contact and prevents wind erosion.
- Production of an even, uniform surface which promotes uniform planting.
- This is deep cultivation into the subsoil layer to break up any hardpan which might have developed.
It is done for the following reasons:–
- To facilitate drainage.
- Bring up leached nutrients to the surface.
- Increase aeration of the soil.
- To improve root penetration.
- The implements used include chisel plough and subsoilers.
- This is the application of a combination of farming practices with the aim of reducing the disturbance of the soil.
Examples of which include:
- Use of herbicides.
- Mulching and cover-cropping.
- Timely operations to prevent weed infestation.
- Strip cultivation.
- Uprooting and slashing of weeds.
Reasons for Minimum Tillage
- To reduce cost of cultivation.
- To control soil erosion.
- To preserve soil moisture.
- To prevent root exposure and damage.
- To reconstruct destroyed soil structure.
Water Supply, Irrigation and Drainage
- Water is a very important natural resource.
- It is necessary for both crops and livest
Uses of water in the farm;
- Cleaning equipment.
- Irrigation in dry areas.
- Processing farm produce, for example, co
- Drinking by livestock and m
- Mixing agro-chemicals such as acaricide, fungicides and herbicides.
- Providing power in water mills to grind grain crop
- Cooling engines.
- Construction work.
Sources of Water in the Farm
Three major sources of water in the farm:
- Surface water:
Includes water from;
- Ground water:
Includes water from;
- Rain water:
This is water tapped in various ways such as;
- Rock surface, when it is raining and stored in various ways.
Collection and Storage of Water
- These are structures constructed across rivers and channel
- They collect and store water for use during the dry season.
- These are structures constructed across rivers to raise the water level for easy pump
- Unlike in the dams water flows over the barrier created across the river.
- Water Tanks:
- These are structures made of concrete, stone, metal sheets and plastics.
- They store water from rain or that which has been pumped from other sources.
- Tanks should be covered to prevent contamination from dust.
Pumps and Pumping of Water
- Pumping is the lifting of water from one point to another by use of mechanical force.
- Water is pumped from the various sources and then conveyed to where it is required for use or storage.
Types of Water Pumps
Used to lift water from its source.
- Centrifugal pumps
- Piston or reciprocating pumps
- Semi-rotary pumps and
Conveyance of Water
- This is the process of moving water from one point, usually the source or point of storage to where it will be used or stored.
- This is where water is moved through pipes.
The common types of pipes include:
- Metal pipes
- Plastic pipes
- Hose pipes
- Use of Containers:
- In this case water is drawn and put in containers .
- drums, jerry cans, pots, gourds, tanks and buckets .
- Which are carried by animals, bicycles, human beings and vehic
- Use of Canals:
- Use of Containers:
- In this case water is conveyed from a high point to a lower one along a gradual slope to avoid soil erosion.
- Water conveyed through this way is mostly used for irrigation and livestock.
- Raw water contains impurities which may be dissolved, floating or suspended in water.
These impurities are grouped into three categories, namely:
- Physical impurities: these are dissolved impurities detected by colour, taste and smell.
- Chemical impurities: these are dissolved impurities detected by use of chemical analysis.
- Biological impurities: these are microorganisms in water such as bacteria, viruses and algae.
Importance of Treating Water
- To kill disease causing microorganisms such as cholera and typhoid bacteria that thrive in dirty water.
- To remove chemical impurities such as excess fluoride which may be harmful to human beings.
- To remove smells and bad taste.
- To remove sediments of solid particles such as soil, sand and sticks.
Methods of Treating Water
- Aeration: this is the removal of smell and odour from water by fine spraying or bubbling of air.
- Sedimentation: this is where water is put in large containers so that solid particles such as sand, metal and others can settle at the bottom.
- Filtration: this is passing water through fine granular materials to remove solid particles and biological substances.
- Coagulation: addition of chemicals which precipitate impurities and help in softening of hard water.
- Chlorination: Sterilization to destroy disease causing organisms.
- It is the artificial application of water to crops in dry areas or where water is not enough.
- It is one of the methods of land reclamation in case of arid and semi arid areas.
Factors to Consider in Identifying and Assessing the Potential of Land for Irrigation Development
- Topography of the land
- Soil type
- Type of crop to be grown
- Water availability
- Human factors such as skill, capital availability and economic activities.
Types of Irrigation
- Surface irrigation:
- This includes flood irrigation and basin irrigation.
- It is used in flat areas.
- The problem with this method is loss of water through seepage.
- It also increases soil salinity.
- Sub-surface Irrigation:
- This involves the use of porous pipes or perforated pipes.
- It is used in slopy areas and where water is inadequate.
- Overhead or Sprinkler Irrigation:
- It is used in any area which is not steep.
- Drip or Trickle Irrigation:
- It is used where water is little and in relatively sloppy and flat areas.
- This is a method of removing excess water or lowering the water table from a marshy water-logged land.
- It is also a method of land reclamation.
Importance of Drainage as a Method of Land Reclamation
- To increase soil aeration.
- To raise soil temperature.
- To increase microbial activities in the soil.
- To reduce toxic substances from the soil.
- To increase soil volume for exploitation by plant roots.
Methods of Drainage
- Use of open ditches.
- Use of underground drain pipes.
- French drains.
- Cambered beds.
- Pumping out water from the soil.
- Planting tree species which absorb a lot of water for example eucalyptus.
- This is the process by which harmful substances get into the water.
- The harmful substance is referred to as a pollutant.
Agricultural practices which pollute water include:
- Use of inorganic fertilizers.
- Use of pesticides.
- Poor cultivation practices such as over cultivation, cultivating along the river banks.
- Overgrazing which leads to erosion of soil thus causing siltation in water sources.
Methods of Preventing Water Pollution
- Soil conservation measures which minimize soil losses through erosi
- Fencing off the water sour
- Adopting organic farming practices for example controlling pests and weed using non-chemical techniques.
- Planting grass along river banks to minimize siltation in rivers.
- Proper disposal of empty chemical containers.
Soil Fertility I
- Soil fertility is the ability of the soil to provide crops with the required nutrients in their proper proportions.
Characteristics of a Fertile Soil
- Good depth – Good soils give roots greater volume to obtain plant nutrients and provide strong anchorage.
- Good aeration – for the respiration of plant roots and use by soil organisms.
- Good water holding capacity – ensures provision of adequate water for plant growth.
- Proper drainage – ensures provision of adequate air for plant growth.
- Correct soil pH – different crops have different soil pH requirements.
- Adequate nutrients supply – it should supply the required nutrients in the correct amounts and in a form available to plants.
- Free from excessive infestation of soil borne pests and diseases.
How soil loses fertility
- Leaching: vertical movement of dissolved minerals from the top to the lower horizons of the soil profile.
- Soil erosion – The removal and carrying away of the top fertile soil from one place to another.
- Monocropping – This is the practice of growing one type of crop on a piece’ of a land over a long time.
- Continuous cropping – crops take away a lot of nutrients from the soil which are never returned.
- Growing crops continuously without giving the soil time to rest makes the soil infertile.
- Change in soil pH – changes in soil pH affect the activity of soil microorganisms as well as the availability of soil nutrients.
- Burning of vegetation – burning of vegetation cover destroys organic matter. It also exposes the soil to the agents of soil erosion.
- Accumulation of salts – soils with a lot of salts are said to be saline. State of having too much salt in the soil is referred to as soil salinity.
- Salts accumulation cause water deficiency in plants. It may also lead to change in soil pH.
Maintenance of Soil Fertility
Soil fertility is maintained through the following methods:
- Control of Soil Erosion ;
- Contour cultivation,
- Strip cropping,
- Cut off drains
- Planting cover crops.
- Crop Rotation ;
- Practice of growing different crops on the same field in different seasons in an orderly sequence.
- Control of Soil pH :
- Application of liming materials such as limestone, quicklime, magnesium carbonate and slaked lime if the soil is acidic.
- Application of acidic fertilizers if the soil is alkaline.
- Application of manures.
- Proper drainage;
- Breaking hard pan.
- Construction of water channels.
- Growing crops on cambered bed
- Pumping out water from the soil.
- Weed control:
- Use of herbicides.
- Use of proper farming practices such as early planting, correct spacing and cover crops.
- Intercropping –
- Farming practice where different crops species are grown together in the field.
- Minimum Tillage;
- Use of herbicides.
- Uprooting of weeds.
- Slashing weeds
- Strip cultivation.
- Use of Inorganic Fertilizer ;
- Chemical compounds manufactured to apply specific plant nutrients for example calcium ammonium nitrate (CAN).
- Use of Manure;
- Well decomposed manures release nutrients into the soil and increase its water holding capacity.
- Manures are derived from plants and animal remains.
- They supply organic matter to the soil which after decomposition releases plant nutrients.
- The end product of this decomposition is known as humus.
- It influences soil chemical properties and soil temperature.
- Manures supply a wide range of essential plant nutrients.
Importance of Organic Matter in the Soil
- Increases the soil water holding capacity of the soil.
- Improves soil fertility by releasing a wide range of nutrients into the soil.
- Provides food and shelter for soil micro-organisms.
- Improves the soil structure.
- Buffers soil pH/moderates soil pH.
- Reduces the toxicity of plant poisons in the soil.
- Moderates soil temperature by its dark colour.
Limitations in the Use of Manure
- They are bulky – low nutritive value per unit volume.
- Laborious in application and transport.
- They spread diseases, pests and weeds.
- Loss of nutrients if poorly stored.
- If not fully decomposed crops may not benefit from them.
Types of Organic Manures
- Green manure.
- Farm yard manure.
- Compost manure
- Made from green plants which are grown for the purpose of incorporating into the soil.
Characteristics of plants used for preparation for green manure:
- Have fast growth rates.
- Have high nitrogen content.
- Capable of rotting quickly.
- Capable of growing in poor conditions.
Preparation of Green Manure
- Plant the green manure crop in the field.
- Allow the crop to grow up to flowering stage.
- Incorporate it into the soil through ploughing.
- Allow the crop to decompose for two weeks.
- Prepare the field for planting the major crop.
Reasons why green manure is not commonly used/limitations:
- Most of the plants used as green manure are food crops.
- Green manure crops may use most of the soil moisture.
- Most of the nutrients are used up by soil micro-organisms in the process of decomposing the green manure.
- Planting of the major crop is delayed.
Farm Yard Manure (FYM)
- Is a mixture of animal waste and crop residues used as beddings in animal houses.
Factors that Determine the Quality of FYM
- The types of the animals used.
- Types of food eaten
- Types of litter used.
- Method of storage.
- Age of farmyard manure.
- Age of the animals used.
Preparation of FYM
- Provide beddings in the houses of farm animals.
- Animals deposit their droppings and urine on the beddings.
- Animals mix them through trampling.
- The beddings together with dung are removed and heaped under shed to decompose.
- After sometime, the materials decompose and FYM is formed.
- It can then be used in the farm
- Is manure prepared from heaped (composted) organic materials.
Factors to consider in selecting site for making compost manure:
- A well drained place.
- Direction of the prevailing wind.
- Size of the farm.
Preparation of Compost Manure
- Four heaps method
- Indore Method (Pit Method)
Indore Method (Pit Method)
- Select a sheltered place with a shade and near the field.
- Dig a pit with the dimension 1.2m x 1.2m x 1.2m.
- Place the materials in the following order:
- Hedge cuttings or maize stalks to a depth of 30cm as a foundation
- A layer of grass, green weeds or leaves and kitchen wastes to 30cm.
- A well rotten manure/poultry droppings.
- Wood ash and phosphatic fertilizers.
- A layer of topsoil to introduce microorganism for the decomposition of organic remains.
- Note: Some water should be sprinkled to the materials to initiate the decomposition process and regulate temperatures.
Four heaps method:
- Clear the site.
- Level the site
- Four posts 2m high are fixed 1.2m apart from four corners of the heap.
- Fix wood planks on the sides.
- Materials are placed in two heaps as in the pit method,
- The two heaps make up heap 1.
- After 3-4 weeks, the decomposed material from heap 1 is transferred to heap II.
- After another 3 – 4 weeks the material is transferred to heap III.
- After 3-4 weeks it is ready for use in the farm.
Indicators of well decomposed manure
- Absence of bad odour.
- Materials are lighter.
- Manure is brown in colour.
Advantages of Compost Manure
- One does not have to own livestock in order to prepare it.
- A lot of manure can be produced within a short time.
- A variety of materials can be used in its preparation.
- Uses locally available materials thus cheaper than the artificial fertilizers.
- Improves the soil structure.
Limitations of Compost Manure
- It releases nutrients slowly into the soil.
- Large quantities of compost manure are required to supply enough plant nutrients.
- Its preparation is labour intensive.
- It may induce soil-borne pests and diseases.
- The term livestock is used to refer to all domesticated animals.
- These animals include cattle, sheep, goats, poultry, pigs, rabbits, camels, bees, fish and donkeys.
The importance of keeping livestock:
- Source of food.
- Source of income.
- Cultural values.
- Source of animal power.
- Provision of raw materials for industries.
- Farmyard manure from the animals is used in maintaining soil fertility.
- Cattle dung is used in the production of biogas.
- Cattle can be classified into two groups based on their origin.
- Indigenous cattle.
- Exotic cattle.
- Zebus –
They are small in size and with a distinct hump and include:
- Maasai cattle.
- The Borana
- These are the cattle kept in the Northern parts of Kenya.
- They are larger than the Zebus.
- Indigenous cattle are hardy hence able to tolerate the harsh environmental conditions in the tropics.
- They are the major suppliers of beef in Kenya.
- Foreign cattle from the temperate regions.
- They have distinct breed characteristics and are classified into various breeds.
- They have no humps.
- They have low tolerance to high temperatures hence popular in cool climates of the Kenya highlands ..
- They are highly susceptible to tropical diseases.
- They have fast growth rates leading to early maturity.
- They are good producers of both meat and milk.
- They cannot walk for long distances.
- They have short calving intervals of one calf per year if well managed.
Exotic cattle breeds fall under the following groups:
- Dairy cattle breeds.
- Beef cattle breeds.
- Dual purpose breeds.
Dairy Cattle Breeds
- They include;
Characteristics of Dairy Cattle
- Wedge or triangular in shape.
- Large stomach.
- Docile with mild temperament.
- Large, well suspended udders and teats.
- Lean bodies.
- Lean and smooth neck.
- Large and long mammary milk wells and veins.
- Cylindrical; uniform and well spaced teats.
- Wide and well set hindquarters to accommodate the udder.
Friesian-Holstein (largest of all dairy breeds)
- Origin: Holland
- Colour: Black and white
- Size: Cow weighs 550-680kgs Bull weighs 950 kg.
- Highest milk producers of all dairy breeds about 9150 kg per lactation but with least butterfat content; 3.5%
- Origin: Scotland
- Colour: White with brown markings.
- Size: Cow weighs 360-590kgs Bulls weighs 500-720kg.
- Straight top lines, horns are long and face upwards.
- Milk production is second to Friesian about 61OOkg per lactation with butter content of about 4%.
- Origin: Guernsey Island off the coast of France.
- Colour: Yellowish brown to red with white legs, switch and girth ..
- Size: Bulls 540-770kg. Cow weighs 450- 500kgs
- Udders are less symmetrical.
- Average milk production is about 5185kg per lactation with a butterfat content of 4.5% hence the yellow colour of milk.
Jersey (smallest of all the dairy breeds)
- Origin: England
- Colour: Yellow brown with black muzzle and switch.
- Size: Bulls weigh 540-700kg. Cow weighs 350-450kgs
- Dished forehead, have straight top-line and level rumps with sharp w
- Have protruding black eyes.
- Average milk production 1270kg per lactation of butterfat content 5%.
- They tolerate high temperatures.
- Aberdeen Angus,
- American Brahman,
- Santa Getrudis.
Characteristics of Beef Cattle
- Blocky or square conformation.
- Have thick muscles or are well fleshed.
- Early maturing.
- Deep chest and girth and short legs.
- Straight top and lower lines.
- Origin: North East Scotland.
- Colour: Black
- Shape: Cylindrical, compact and deep; It is polled.
- Mature bulls weigh 900kg.
- Mature cows weigh 840kgs.
- It is found in Timau area of Kenya
- Origin: Engla
- Colour: Deep red and white-faced.
- Size: Average weight of bulls is 1000kg.
- Cows weigh 840kgs.
- It is found in areas such as Naivasha.
- Origin: England.
- Has easy fleshing ability
- Colour: Red, Roan or white
- Shape: Cylindrical, compact and deep.
- It is polled.
- Bulls weigh 700-900kg,
- cows weigh 545-630kgs.
- Origin: Scotland.
- Colour: Black
- Kept in the highland areas like Molo in Kenya.
- Origin: France.
- Colour: Creamy white.
- Size: Bulls weigh 1200kg, cows weigh 1000kgs.
- It is found in ranches in Laikipia District.
Dual Purpose Breeds
Examples: Sahiwal, Red Poll and Simmental.
- Origin: India and Pakistan ..
- Colour: reddish brown.
- Size: Bulls weigh 650kg, and cows 400kg.
- Milk production averages 2700-3000 per lactation with a butter fat content of 3.7%.
- It has a pendulous udders which does not let down milk easily.
- It is therefore said to be a difficult milker.
- It is kept in semi-arid areas such as Naivasha.
- Origin: England.
- Colour: Deep red with a white nose.
- Conformation: Polled-deep girth and short legs.
- Kept in semi–arid areas such as Nakuru, Mogotio.
- Colour: Light red and white patches on the head.
- It has broad and straight back, with well-sprung ribs and deep girth.
- It is well fleshed at rear quarters, well suspended udders and large teats.
Purpose of Keeping Sheep;
- Meat (mutton).
- Wool production.
- Wool breeds -for example merino.
- Dual purpose- for example Corriedale, Romney marsh.
- Mutton breeds -for example Hampshire Down, Dorpers.
- Origin: Spain
- It has white face and its lips and nostrils are pink in colour.
- Rams have horns which are spiral in shape.
- It is susceptible to foot rot, worm and respiratory diseases.
- Origin: New Zealand.
- Size: Rams 85 – 90kg. Ewes 60– 85 kg
- This is a dual-purpose breed with white open face and white spots on the legs.
- It is hornless and hardy.
- Origin: England.
- Size: Rams 100 – 115kg.
- Ewes 84- 100 kg
- It is a dual-purpose breed which s hornless with wide poll and black nostrils and lips.
- It is average in prolificacy.
- It is resistant to foot rot diseases and worm infestation.
- Origin: England.
- Size: Rams 125kg.
- Ewes 80-100 kg
- It is a mutton breed which is early maturing, hardy and prolific.
- Fleece is of poor quality because of the black fibres.
- Lambing percentage is 125-140.
- Is a crossbreed of Dorset horn and black head Persian sheep.
- It is mutton breed.
- Dual purpose breed of sheep.
- Indigenous Breeds of Sheep
- Their bodies are covered with hair.
- Their classification is based on their tails and their names vary according to different tribes.
- Thin tailed sheep found in West Africa.
- Fat tailed such as Maasai sheep.
- Fat rumped sheep.
- Found in South Western Kenya and Northern Tanzania.
- Size: Ram 38kg,
- Ewe 20-30kg.
- Colour: Red and brown.
- These are early maturing with long legs and small pointed horns.
Black Head Persian Sheep
- Origin: South Africa
- Colour: White with black head and neck.
- It is polled with a big dewlap, fat rump and a curved tail..
Goats well adapted to a wide range of environmental conditions because of the following characteristics:
- They feed on a wide range of vegetation.
- They require very little amount of water.
- They are tolerant to high temperatures.
- They are fairly resistant to diseases.
- They can walk long distances without losing weight.
Indigenous Goat Breeds
- Galla (white in colour). Adult female can weigh 25kg.
- Somali (Boran): Found in Northern Kenya (white in colour).
- Turkana/Samburu: (Long hair and bearded.
- Mubende: (Black) (40-45kg). These are small and hardy and are kept for meat and milked by the pastoralists.
- Origin: South Africa
- Colour: White
- Has long ears and long hair on their bodies.
- Origin: North East Africa
- Colour: Roan and White
- These have long legs, lopped ears and are polled.
- They produce 1-2 litres of milk per , day.
- Origin: India
- Colour: White, black and fawn.
- They are horned, have large lopped ears
- Produce 1-1.5_litres of milk per day.
- Origin: Switzerland
- Colour: White patches on the body, white stripes on the face and neck.
- Erect forward pointing ears and polled.
- Can produce 2-3 of milk per day.
- Origin: Switzerland.
- Colour: White
- They have erect, forward pointing ears and polled.
- Can produce 2-3 Iitres of milk per day.
- Origin: Angora in Asia.
- Colour: White
- It is kept for wool production.
French alpine. Pigs
- They are sparsely haired and therefore cannot withstand cold.
- Pigs wallow when it is hot due to absence of sweat glands.
- They breathe fast when it is hot.
- They have bristles instead of hair.
- Origin: Britain
- _ Kept for bacon and pork production.
- Long, large and white in colour.
- Ears straight and erect.
- Has dished face and snout.
- Most prolific and with good mothering ability.
- Fairly hardy.
- Origin: Denmark
- White and longer than large white. _
- Ears drooping.
- Good for bacon production.
- Very prolific with good mothering ability. _
- Requires high level of management.
- Back Origin: England
- Colour: Black with white forelegs and shoulders.
- Straight snout and drooping ears. _
- Good for bacon and pork.
- Good for keeping outdoors.
- Excellent mothering instincts.
Other pig breeds include:
- Duroc Jersey pig.
Pigs can be crossed to obtain hybrids or crosses.
Advantages of Crosses
- Increased litter size. _
- Early maturing.
- _ Increase in body length.
- _ High proportion of lean meat to fat.
There are three types of chicken breeds:
- The light breeds kept for egg production.
- The heavy breeds kept for meat production.
- Dual purpose breeds – kept for both eggs and meat production.
Characteristics of Light Breeds
- Never go broody hence poor sitters.
- Excellent layers (over 220 eggs per year).
- Poor meat producers (hens can attain 2kg; cocks 3kgs)
- Very nervous and exhibit high degree of cannibalism.
- Hen’s comb is large and bent over one eye and cock’s comb is large with 5 – 6 serrations.
Characteristics of Heavy Breeds
- Can lay few eggs and provide good meat as broilers.
- Can go broody.
- Heavier and bigger in size.
- Grow fast.
- Light Sussex,
- Cornish Dark
Characteristics of Dual–Purpose Breeds
- Go broody.
- Have good meat.
- Disease resistant (do not require high standard of management).
- Rarely exhibit cannibalism.
Examples: Rhode Island Red.
- These are developed by crossing two different breeds.
- They are superior in performance.
- Can attain 2kg in 56 days for broilers and layover 200 eggs per year for layers.
Kept for the following reasons:
- To provide meat, fur, hair or wool.
- To provide skin for leather.
- To provide manure.
- As pet ani
- Used for research purposes.
- Californian white: white, very prolific black ears, nose and feet).
- New Zealand white: (white with pink eyes – good for meat).
- Flemish giant (dark grey – good for meat).
- Angora rabbit (white, kept for wool production).
- Chinchillah (greyish, kept for its fur).
- Earlops (white with droopy ears).
- Kenya white (white, smallest of breeds).
- To provide milk, meat and wool.
There are two species of camels.
Dromedary (Camelus dromedarius)
- Origin: Arabia and Syria
- Are single humped, have light body
- Good for racing and rapid transport.
Bacterian (Camelus bacterianus)
- Origin: Central Asia
- Has double humps, heavier and has shorter legs.
- Can live in cold regions hence its thick and long coat acts as insulation.
- Capable of shedding the coat during spring.
Terms used to describe livestock in different age, sex and use.
|Cattle||Bull||Cow||Bullock||Heifer||Calf||Dairy – milk
|Sheep||Ram||Ewe||Ram||Hogget||Lamb||Mutton – meat
Wool sheep -wool
|Goat||Buck or||Doe or||Buck||Doe||Kid||Dairy – milk|
|Billy||Nanny||Mutton – meat|
|Pigs||Boar||Sow||Boar||Gilt||Piglet||Pork – meat|
|Poultry||Cock||Hen||Cockerel||Pullet||Chick||Broilers – meat|
|Layers – eggs|
|Camel||Bull||Cow||Bull||Heifer||Calf||Pack, trained for|
|riding, racing milk,|
Agricultural Economics I
(Basic Concepts and Farm Records)
- Economics is the study of how man and society chooses to allocate scarce productive resources to produce various commodities, over time, and distribute them among various consumers in society.
- It attempts to explain how man can best use the limited resources to produce goods and services which satisfies his needs with minimum wastage or loss of these resources
- Agricultural economics is therefore defined as a science that aims at maximizing output while minimizing costs by combining the limited supplies of goods and services for use by the society over a certain period of ti
- These are;
Basic economic Principles
- Economic scarcity means resources are limited in supply relative to demand.
- This principle implies that there is no time that man can have enough resources to satisfy all his need or desires
- Human wants are many and varied and means of satisfying them are limited.
- Therefore, man has to make a choice among the alternatives in order to use the resources available.
- Man does this by satisfying the most pressing needs first.
- This is called scale of preference.
- Opportunity cost is the revenue forgone from the best alternative.
- It exists only where there are alternatives.
- Where there are no alternatives the opportunity cost is equal to zero.
- Opportunity cost helps in decision making.
- Farm records are documents kept in the farm
- They show farm activities carried out over a long period of time
- Or information kept in the farm in written form, about the farm and all activities in it.
Uses of Farm Records
- Show the history of the farm
- Show whether the farm is making a profit or loss.
- Show all the assets and liabilities of the farm which can be used to value the farm.
- Help in supporting insurance claims on death, theft, fire or loss of farm assets.
- Help in tax assessment to avoid over taxation.
- Used as a guide in planning and budgeting.
- Helps to detect losses or theft in the farm.
- Make it easy to share profits or losses in partnerships.
- Help in settling disputes among heirs to estate if the farmer dies without a will.
- Provide labour information on terminal benefits for a worker.
Type of Farm Records
- Production Records – Show the total yield and yield per unit of each enterprise.
- Inventory Records – A record of all permanent and consumable goods in the farm.
Consumable Goods Inventory
- Field Operation Records – Show in details all field practices carried out together with the input used for all the crop enterprises.
- Breeding Records –
- Show all the breeding activities in the farm.
- From these records it is possible to select the prolific animals and cull the infertile ones.
- Feeding Records – A record of the types of feeds used in the farm and their quantities.
- Health Records –
- Indicates the health conditions of the animals in the farm.
From these records it is possible to:
Select and cull animals on health grounds. Soil Fertility II
- Plant nutrients occur in the soil in form of soluble substances.
- These substances are taken in by the plants in different quantities depending on their roles in the plant tissues.
- These are nutrients needed by plants for various uses.
- They are divided into two broad categories namely:
- These are also referred to as major nutrients.
- They are required by the plant in large quantities.
- Nitrogen, phosphorus and potassium are referred to as fertilizer elements,
- Calcium, magnesium and sulphur, are referred to as liming elements.
Role of Macronutrients in Plants
- Artificial fertilizers
- Organic matter
- Atmospheric fixation by lightning
- Nitrogen fixing bacteria.
Role of Nitrogen in Plants
- Vegetative growth
- Chlorophyll formation
- Build up of protoplasm.
- Improves leaf quality in leafy crops such as tea and cabbages.
- Yellowing of the leaves/chlorosis.
- Stunted growth.
- Premature ripening.
- Premature shedding of the leaves.
- Light seeds.
Effect of Excess Nitrogen
- Scorching of the leaves.
- Delayed maturity.
Loss of Nitrogen From the Soil:
- Soil erosion.
- Crop removal.
- Used by microorganisms.
Phosphorus (H2 P04, HPO2-4 P2O5)
- Organic manures
- Commercial fertilizers
- Phosphate rocks
Role of Phosphorus
- Encourages fast growth of the roots.
- Improves the quality of the plant.
- Hastens maturity of the crops.
- Influences cell division.
- Stimulates nodule formation in legumes.
- Growth of the plant is slow.
- Maturity is delayed.
- Leaves become grey, purple in colour.
- Yield of grains, fruits and seed is lowered.
Loss of Phosphorus From the Soil
- Soil erosion.
- Crop removal
- Fixation by iron and aluminium oxide.
Potasium (K+, K2O)
- Crop residue and organic manures.
- Commercial fertilizers
- Potassium bearing minerals e.g. feldspar and mica.
Role of Potassium in Plants
- Increases plant vigour and disease resistance.
- Increases the size of grains and seeds.
- Reduces the ill-effects due to excess nitrogen.
- Prevents too rapid maturation due to phosphorus.
- Plants have short joints and poor growth.
- Plants lodge before maturing.
- Leaves develop a burnt appearance on the margin.
- Leaves at the lower end of the plant become mottled, spotted or streaked.
- In maize, grains and grasses firing starts at the tip of the leaf and proceeds from the edge usually leaving the midrib green.
Loss of Potassium From the Soil
- Crop removal.
- Soil erosion.
- Fixation in the soil.
- Crop residues and organic manures.
- Commercial fertilizers.
- weathering of soil minerals.
- Agricultural limes for example dolomite, limestone.
Role of Calcium in Plants
- Improves the vigour and stiffness of straw.
- Neutralizes the poisonous secretions of the plants.
- Helps in grain and seed formation.
- Improves the soil structure.
- Promotes bacterial activity in the soil.
- Corrects the soil acidity.
- Young leaves remain closed.
- There are light green bands along the margins of the leaves.
- Leaves in the terminal bud become hooked in appearance there is a die-back at the tip and along the margins.
Loss of Calcium
- Crop removal
- Soil erosion
- Crop residues and organic manures
- Commercial fertilizers
- Weathering of soil minerals.
- Agricultural limes.
Role of Magnesium in Plants
- Forms part of chlorophyll.
- Promotes the growth of the soil bacteria and enhances the nitrogen fixing power of the legumes.
- Activates the production and transport of carbohydrates and proteins in the growing plant.
- Loss in green colour which starts from the bottom leaves and gradually moves upwards.
- The veins remain green.
- Leaves curve upwards along the margins.
- Stalks become weak and the plant develops long branched roots.
- The leaves become streaked.
Sulphur (S04 2- ,SO2)
- Commercial fertilizers.
- Soil mineral containing sulphides
- Atmospheric sulphur from industries.
- Rain water
Role of Sulphur in Plants
- Formation and activation of coenzyme-
- Sulphur is a constituent of amino acids.
- Influence plant physiological processes.
- Small plants/stunted growth.
- Poor nodulation in legumes.
- Light green to yellowish leaves/ chlorosis.
- Delayed maturity.
- Also referred to as trace or minor nutrients.
- They are required in small quantities/traces.
- They are essential for proper growth and development of plants.
Role of Micronutrients and Their Deficiency Symptoms
- Role in oxidation-reduction reactions.
- Respiration and utilization of iron
- Deficiency symptoms-yellowing of young leaves.
- Synthesis of proteins.
- Takes part in oxidation-reduction reactions.
- Deficiency symptoms – leaf chlorosis
- Nitrogen transformation in plants.
- Metabolization of nitrates to amino acids and proteins
- Deficiency symptoms –leaf curl and scathing.
- Manganese – Same as molybdenum.
- Formation of growth hormone.
- Reproduction process
- Deficiency symptoms – white bud formation.
- Boron –
- Absorption of water.
- Translocation of sugar
- These are chemically produced substances added to the soil to improve fertility.
Classification According to:
- Nutrients contained
- Straight – contain only one macronutrient.
- Compound fertilizers – contain more than one macronutrient
- Time of application
- Some applied when planting.
- Top dressing after crop emergence
- Effects on the soil pH.
- Acidic fertilizers.
- Neutral fertilizers.
- Basic fertilizers.
Properties and Identification of Fertilizers
- Highly soluble in water.
- Highly mobile in the soil hence it is applied as a top dress.
- Easily leached because of the high solubility hence does not have residual effect on the soil.
- Has scorching effect on young crops during wet seasons.
- Easy to volatilize during hot season.
- They have a tendency to cake under moist conditions.
- They are hygroscopic hence should be stored in dry conditions.
- Sulphate of Ammonia (NH4) 2 SO4
- white crystals,
- Has acidic effect,
- Contains 20% N.
- Ammonium Sulphate Nitrate [(NH4)2 SO4+ NH4 NO3]
- Colour: granules which appear yellow orange,
- less acidic,
- contains 26% N.
- Calcium Ammonium Nitrate (CAN)
- Colour: greyish granules,
- neutral in nature,
- contains 21 % N.
- Colour: small whitish granules
- Easily leached or volatilized,
- contains 45- 46%N.
- Has low solubility and immobile.
- Has a high residual effect hence benefit the next season’s crop.
- Easy to store because they are not hygroscopic.
- Single super-phosphate
- Appearance: whitish, creamy white granules,
- contains 20-21 % P2O5
- Double super-phosphate
- Appearance: dark greyish granules,
- Contains 40-42% P2O5
- Triple super-phosphate
- Appearance: small greyish granules,
- Contain 44-48% P2O5
- Has moderate scorching effect.
- Moderately soluble in water.
- Most Kenyan soils have sufficient potassium.
- Muriate of Potash (KCl)
- Contain 60 – 62% K2O
- Slightly hygroscopic.
- Appearance amorphous white.
- Sulphate of Potash (50% K2O)
Compound or Mixed Fertilizers
- These are fertilizers which supply 2 or more of the macronutrients.
- Mono ammonium phosphate.
- Di-ammonium phosphate
- 20:20:20, 23:23:23
Advantages of application of compound fertilizers
- Saves time and money.
- Mixture gives improved storage properties and better handling.
Disadvantages of compound fertilizers application
- Mixing may not be thorough.
- Incompatibility of the individual fertilizers.
Methods of fertilizer application
- Broadcasting – random scattering of the fertilizers on the ground.
- Placement method – application of fertilizers in the planting holes.
- Side dressing – fertilizer is placed at the side of the plant within the root zone, in bands or spot-rings.
- Foliar spraying – specially formulated fertilizer solution applied on the foliage in spray form.
- Drip method – applied through irrigation water.
Determination of Fertilizer Rates
Contents of fertilizers are expressed as fertilizer grade or fertilizer analysis.
- Fertilizer grade indicate the guaranteed minimum of the active ingredients (N, P2O5, K 2O) in the mixture.
- It is expressed as a percentage on a weight to weight basis or percentage by weigh
Example 10:20:0 means for every 10kg of the mixture there are 10kg of nitrogen, 20kg of P2O 5 and 0kg of K2O.
A farmer was asked to apply fertilizers as follows:
- 60 kg/ha nitrogen (top dressing)
- 60 kg/ha P2O5 (in planting hole).
- 60 kg/ha K2O.
How much sulphate of ammonia (20%) would be required per hectare?
How much double super-phosphate (40%) P2O5would be required per hectare?
How much muriate of potash (50% K2O) would be required per hectare?
- Sulphate of ammonia (SA) which gives 60kg/ha N
20x 100 =300kg SA
- Double super phosphate (40% P2O5)which gives 60kg/ha P2O5
= 40x 100 =150kg DSP
- Muriate of potash (60% K2O) which gives 60kg/hK2O
= 60 x 100=100kg muriate of potash
A farmer was asked to apply fertilizers as follows:
- 200kg/ha of DSP (40% P2O5
- 150kg/ha of muriate of potash (60% K2O)
- 150kg/ha of sulphate of ammonia (20% N)
How much P2O5 did the farmer apply per acre?
How much K2O did the farmer apply per hectare?
How much N did the farmer apply per hectare?
- P2O5 applied per hectare from 200kg of DSP
= 100x 200= 80kg/ha P2O 5
- K2O5 applied per hectare from 150kg of muriate of potash
= 100×150=90kg/ha K2O
- N applied per hectare from 150kg/ha sulphate of ammonia
= 100 x 150= 30kg/ha N
- Refers to obtaining of small quantity of soil that is representative in all aspects of the entire farm.
Soil Sampling Procedures
- Clear the vegetation over the site.
- Dig out soil at depths of 15-25cm.
- Place the dug out soil in a clean container.
- Mix thoroughly the soil in the container.
- Take a sample and send it to National Agricultural Laboratory for analysis.
- The container carrying the sample should be properly labeled as follows:
- Name of the farmer,
- Address of the farmer.
Sites to Avoid
- Dead furrows, ditches.
- Near manure heaps.
- Recently fertilized fields
- Ant hills.
- Under big trees.
- Near fence lines or foot paths.
- Do not put them in containers which are contaminated with fertilizers or other chemical containers.
Methods Of Soil Sampling:
- Zigzag method
- Traverse method
- Soil testing is the analyzing of the soil sample to determine certain qualities of the soil.
Importance of Soil testing:
- To determine the value of the soil hence determine the crop to grow.
- To determine the nutrient content hence find out the type of fertilizer to apply.
- To determine whether it is necessary to modify the soil pH for a crop.
How Soil pH affects Crop Production
- Influences the physical and chemical properties of the soil.
- Affects the availability of nutrients.
- Influences the incidences of soil borne diseases.
- Determine the type of crop to be grown at a given area.
Methods of pH Testing
- Universal indicator solution
- pH meter
- Know the course of action to be taken in the event of a disease and maintenance of good health.
- Know the prevalent diseases.
- Calculate the cost of treatment.
- Marketing Records show commodities sold, quantities and value of all the sales.
Labour Records – show labour utilization and labour costs. Crop production II (Planting)
- Planting is the placement of the planting material in the soil for the purpose of regeneration in order to produce more of the plant species.
Types of planting materials
- Seeds are produced by flowering after pollination and fertilization. They contain the part of the plant that germinates and subsequently grows in to new plants.
Advantages of using seeds as planting materials.
- Seeds are easily treated against soil borne pests and diseases.
- They are not bulky therefore storage is easy.
- They are easy to handle during planting making operation easy.
- When planting seeds, it is easy to use machines like seed planters and drillers.
- It is easy to apply manures and fertilizers together with seeds during planting.
- Fertilizers and manures application can be easily mechanized.
- It is possible to develop new crop varieties due to cross pollination.
Disantivantages of using seeds as planting materials.
- Some seeds have long dormancy and they may need special treatment in order to germinate.
- Plants raised from seeds have variations from the mother plant due to cross pollination, This may introduce undesirable characteristics.
- Soil borne pests may damage seeds if left for sometime in the soil before rain falls.
- Some seeds may lose viability if stored for a long time. This leads to gaps in the farm.
- Vegetative materials.
- These are plant parts which have the ability to produce roots, they grow and develop in to new plants.
- Plant parts such as leaves, roots or stems can be used for planting as long as they are capable of rooting.
Advantages of using vegetative materials for planting.
- Crops originating from vegetative materials matures faster than those from seeds.
- The crops shows uniformity in such qualities as disease resistance, seed size, colour, keeping or storing quality and chemical composition.
- It is possible to produce many varieties of compatible crops on the same root stock.
- Use of the vegetative materials is easier and faster, especially where seeds show prolonged dormancy.
- The resulting plant has desired shape and size for ease of harvesting and spraying.
- It facilitates the propagation of crops which are seedless or those that produce seeds which are not viable or have a long dormancy period.
- Such crops include sugar-cane, bananas, Napier grass and others.
- Vegetative propagation does not result in new crop varieties.
- Keeping the materials free of diseases is difficult.
- Materials cannot be stored for long.
- The materials are bulky and there fore difficult to store and transport.
Plant parts used for vegetative propagation.
- These are tiny sisal plants produced in the inflorescence almost at the end of the plant growth cycle.
- They resemble the mother plant except that they are smaller in size.
- They are produced by the branches of the sisal pole.
- When manure they mature they develop rudimentary roots and fall off to the ground just below the pole.
- They are the collected and raised in the nurseries before they are transplanted t\o the main field.
- One sisal pole may produce as many as 3,000 bulbils. They are usually 10cm long. They make good planting materials and are better than sucke
- These are plantlets divided from the existing mother plant with complete with complete leaves and rooting system.
- They are used to propagate most pasture grasses and pyrethrum.
- Pyrethrum splits are raised first in nursery and then transplanted to the field.
- Crowns and slips
- These are materials used to propagate pineapples
- Crowns are born on top of the fruits and are broken off and prepared for planting.
- They are more preferred to suckers because they give uniform growth and take two years to reach maturity.
- Slips are borne to the base of the pineapple fruits.
- They are cut and prepared for plantings.
- Their growth rate is faster than for crowns giving average uniformity.
- They take 22 months from planting to maturity.
- Crowns and slips are planted in the nurseries first before transplanting to the main seed bed.
- These are small plants that grow from the base of the main stem.
- They have adventitious roots which grow quickly when planted to form a new plant.
- They are used to propagate bananas, sisal, and pineapples.
- When planted, suckers give uneven growth leading to maturity at different times. T
- hey should be planted when they are young.
- These are underground food storage organs which are short and thick.
- They are used as vegetative propagation materials because they sprout and produce roots for growth.
- There are mainly two types of tubers, the stem and root tubers.
- Root tubers develop from the thickening of the adventitious roots.
- Root tubers are not commonly used for propagation since they produce weak stems.
- A good example of a root tuber is the sweet potato.
- On the other hand stem tubers have some auxiliary buds which are sometimes referred to as ‘eyes’.
- These eyes sprout to produce stems which grow into plants. Stem tubers are therefore swollen stems with scales leaves.
- A good example of a stem tuber is Irish potato.
- These are soft wood cuttings which produce roots easily upon planting to give rise to new plants.
- They are cut from the mother plants and planted directly into the field.
- Soft wood cuttings (vines) are taken from rapidly growing shoots.
- The soft upper parts of the shoots are preferred.
- When preparing the cuttings, some leaves and nodes are included.
- Roots are produced from the nodes.
- Cuttings and setts
- Cuttings are portion of plants parts which are cut and then planted.
- They may be from stems, roots or leaves.
- A stem cutting must have a bud which develops into shoot.
- The root cutting must have an eye. Cutting must have an eye.
- Cuttings must produce leaves as soon as possible so that they can start making their own food.
- Sometimes cuttings are induced to produce roots by use of rooting hormones.
- Once the cuttings have developed roots, they give rise to new plants.
- In some crops, the cuttings are big enough to be planted directly to the main seedbed whereas there are some plants whose cuttings are first raised in special nurseries before they are transplanted to the seedbed.
- The cuttings of Napier grass and sugar-cane are planted directly on the seedbed but those of tea; have to be raised in special nursery before they are transferred to the seed bed.
- Examples of crops which are propagated by use of stem cuttings include: tea, cassava, and sugar-cane and Napier grass.
- The stem cuttings used to propagate sugar-cane are known as ‘setts’. Setts are stem cuttings which have 3-5 nodes are usually 30-45 cm long.
Factors affecting rooting of cuttings.
- Temperature: for the cuttings to produce roots warm temperatures are required around the root zone while cool temperatures are important for the aerial part of the cuttings. For most species optimum day and light temperatures for rooting are 22 -27°c and 15-21° c respectively.
- Relative humidity: Proper rooting of cuttings requires high humidity which lower the transpiration rate. It also increases and maintains leaf turgidity all the time. As such, cuttings should be rooted in green houses or under shady conditions, where relative humidity can be regulated. Sometimes the propagation area can be sprayed with water to keep it moist.
- Light intensity: soft wood cuttings need high intensity light to produce roots. This is because light promotes the production of roots since it affects the rate of photosynthesis. Hard wood cuttings do well in dark conditions since they have high amount of stored carbohydrates and therefore rooting is excellent in darkness.
- Oxygen supply: plentiful supply of oxygen is required for root formation. The rooting medium used must therefore be capable of allowing proper aeration.
- Chemical treatment: these rooting hormones which promote the production of roots in cuttings. The common ones include IAA (Indoleacetic acid).
- Leaf area: Soft woods cuttings require a lot of leaves for photosynthesis while hardwood cuttings will produce roots better without leaves.
Selection of planting materials
When selecting materials for planting the following factors must be considered:
- Suitability to the ecological conditions – the selected planting materials should be well adapted to the soil conditions, temperatures and amount of rainfall in the area. There are many varieties of maize, for example, which are suitable to different ecological conditions. Hybrid 622f or example is mainly for the high altitudes areas of Kenya 513 for the medium altitudes and the Katumani composites for the low rainfall areas while the coast composites are suitable for the coastal conditions each variety will grow well and produce high yields if grown under the correct conditions
- Purity of the materials – planting materials should be pure and not mixed with other off types the percentage purity of planting materials will affect the seed while higher seeds rates are used for impure seeds.
- Germination percentage – This is a measure of the germination potential of seeds it is expressed as a percentage for example a germination percentage of 80 means that for every 10 seeds planted 80 of them are expected to germinate. Germination percentage helps to determine the seed rates of crops lower seed rates are used for crops with higher germination percentage while higher seed rates are used for those with lower germination percentage.
- Certified seeds – These are seeds which have been tested and proven to have 100 germination potential and free from diseases and pests they give high yields after the first planting but the subsequent yields decline if replaced therefore in this case it is always advisable to buy new seeds which are certified every time planting is done
In Kenya certified seeds are produced by the Kenya seed company (KSC) and distributed by Kenya Farmers Association (KFA) and other agents.
PREPARATION OF PLANTING MATERIALS.
After the planting materials are selected they are prepared in different ways before they are planted. Some of the methods used to prepare planting materials include the following:
(a)Breaking the seed dormancy.
Some seeds undergo a dormancy period between maturity and the time they sprout. The dormancy period is the stage whereby a seed cannot germinate, the stage of inhibited growth of seed. It should be broken before the seed is planted.
Methods of breaking seed dormancy.
The following methods are used to break seed dormancy:
(I) Mechanical method: This is a method which aims at scratching the seed coat to make it permeable to water. Scarification is done by rubbing small sized seeds against hard surface such as sand paper, while filling or nicking the seed coat with a knife is done to large sized seeds such as croton seeds.
(ii) Heat treatment: this involves the use of hot water or burning the seeds lightly. It softens the seed coat making it permeable to water and thus is able to germinate. The seeds are soaked in hot water about 80’c for 3-4 minutes after which the water is allowed to drain off. Example of seeds treated in this way include: leucean calliadra and acacia.
Light burning also serves the same purpose as hot water treatment. In this case trash is spread over the seeds which are already covered with a thin layer of soil. The trash is burned, after which the seeds are retrieved and planted. Examples include acacia and wattle tree seeds. Overheating should be avoided as this will cook the seeds.
(iii)Chemical treatment: seeds are dipped in specific chemicals such as concentrated sulphuric acid, for two minutes and then removed. The chemical wears off the seed coat making it permeable to water. Care should be taken not to leave the seeds in the chemicals for too long as this will kill the embryo. Cotton seeds are normally treated with chemicals to remove the lint or fibres.
- iv) Soaking in water: seeds are soaked in water for a period of between 24 – 48 hours until they swell. They are then removed and planted immediately. The seeds treated thus germinate very fast. Pre-germinated seeds are used when raising rice in the nurseries.
- b) Seed dressing
This is the coating of seeds with fungicides or an insecticide or a combination of the two chemicals. This is particularly common with cereals, sugar-cane and legumes.
The chemicals protect the seedlings from soil-borne diseases and pests. Certified seeds which are sold by seed merchants in Kenya have been dressed with these chemicals. Farmers can also buy the chemicals and dress their own seeds.
- C) Seed inoculation
In areas where soils are deficient in nitrogen, legumes such as beans, clovers and peas should be coated with an inoculant. An innoculant is a preparation which contains the right strain of Rhizobium depending on the type of legume and encourages nodulation, hence nitrogen fixation. Below is a table showing different legume crops and their right strain of Rhizobium.
|Crop inoculation group||Rhizobium Species|
When handling inoculated seeds, care should be taken to prevent them from coming in contact with chemicals. This means that inoculated seeds should not be dressed with chemicals as these will kill the bacterium. They should also be planted when the soil is moist to avoid dehydration which kills the bacterium.
- d) Chitting
This practice is also referred to as sprouting. The selected seed potatoes ‘setts’ which are used as planting materials are sprouted before planting to break their dormancy. The setts of about 3-6 cm in diameter are arranged in layers of 2 or 3 tubers deep in a partially
darkened room. The setts should be arranged with the rose- end facing upwards and the heel-end downwards. Diffused light encourages the production of short, green and healthy sprouts. If Chitting is done in complete darkness, long, pale thin sprouts develop which break easily during planting. During Chitting potato aphids and tuber months should be controlled by dusting or spraying the sett with dimethoate. Sometimes a chemical known as Rendite is used to break dormancy, thus inducing sprouting. Chitting is done mainly to make sure that growth commences immediately the seed is planted so as to make maximum use of rains for high yields.
Time of planting
The timing of planting or sowing is influenced by the type of crop to be planted and the environmental conditions of the area.
Factors to consider in timing planting.
- The rainfall pattern/moisture condition of the soil.
- Type of crop to be planted.
- Soil type.
- Market demand.
- Prevalence of pests and diseases.
- Weed control.
Timely planting is necessary and should be done at the onset of rains. In some areas where rainfall is scare dry planting is recommended.
Advantages of timely planting.
- Crops make maximum use of rainfall and suitable soil temperature, leading to vigorous growth.
- Crops usually escape serious pests and diseases attack.
- Crops benefit from nitrogen flush which is available at the beginning of the rain.
- For horticultural crops, proper timing ensures that the produce is marketed when prices are high.
- Crops establish earlier than the weeds, hence smothering them.
Methods of planting.
There are two main methods of planting :-
- Row planting.
This method involves scattering the seeds all over the field in a random manner. It is commonly adapted for light tiny seeds such as those of pasture grasses. It is easier, quicker and cheaper than row planting. However, it uses more seeds than row planting and the seeds are spread unevenly leading to crowding of plants in some places. This results in poor performance due to competition. Broadcasting gives a good ground cover, but weeding cannot be mechanized. For good results, the seedbed should be weed-free, firm and have a fine tilth.
The seeds or other planting materials are placed in holes, drills or furrows in rows. The distance between one row to the other and from one hole to the other is known. In Kenya, both large and small – scale farmers practice row planting. It is practiced when planting many types of crops, especially perennial, annual and root crops.
Advantages of row planting.
- Machines can be used easily between the rows.
- It is easy to establish the correct plant population.
- Lower seed rate is used than if broadcasting is adopted.
- It is easy to carry out cultural practices such as weeding, spraying and harvesting.
Disadvantages of row planting.
- It does not provide an ample foliage cover. Thus the soil is liable to being eroded by wind and water.
- It is more expensive than broadcasting because of consuming a lot of labour and time.
- It requires some skill in measuring the distances between and within the rows.
Seeds can also be planted by dibbling where the planting holes are dug by use of pangas or jembe, or by a dibbling stick (dibbler). Most of the dibbling is done randomly although rows can also be used when using a planting line. Random dibbling is not popular in commercial farming due to low levels of production. It is only common among conservative farmers in planting of legumes such as beans, pigeon peas and cow peas.
This is the introduction of a pasture legume such as desmodium in an existing grass pasture. Some form of growth suppression of existing grass such as burning, slashing or hard grazing plus slight soil disturbance is recommended before over sowing. A heavy dose of superphosphate, preferably single supers at a rate of 200-400 kg/ha is applied. The grass must be kept short until the legume is fully established. Regardless of the method of establishment, the pastures and fodder stands should be ready for light grazing 4-5 months after planting if rainfall and soil fertility are not limiting.
This refers to the establishment of pasture under a cover crop, usually maize. Maize is planted as recommended and weeded 2-3 weeks after the onset of rains. Pasture seeds are then broadcasted with half the recommended basal fertilizer. No further weeding should be done and maize should be harvested early to expose the young pasture seedlings to sunlight. The benefits of under sowing include facilitating more intensive land utilization and encouraging an early establishment of pastures.
Fodder crops and vegetetively propagated pasture species may also be under sown as long as rainfall is adequate for their establishment. Timing is not very crucial in this case and planting can be done as late as 6-8 weeks after the onset of rains.
This refers to the ideal number of plants that can be comfortably accommodated in any given area, without overcrowding or too few to waste space. Agricultural research has arrived at the optimum number of various crop plants to be recommended to farmers. Plant population is determined by dividing the planting area by spacing of the crop. This may be simplified thus:
Area of land
Plant population =
Pacing of crop
Given that maize is planted at a spacing of 75 x25 cm, calculate the plant population in a plot of land measuring 4×3 m.
Area of land
Plant population =
Pacing of crop
Area of land = 400cm x 300 cm
Spacing of maize = 75 cm x 25 cm
Therefore, plant population = 400 cm x 300 cm
75 cm x 25 cm
= 64 plants.
It is the distance of plants between and within the rows. Correct spacing for each crop has been established as shown in table below.
|75 – 90 cm x 23 – 30 cm|
(Arabica) tall varieties
|2.75 cm x 2.75m|
|Tea||1.5 m by 0.75 m|
|Beans (erect type)||45 -60 m by 25 cm|
|Bananas||3.6 – 6.0 m by 3.6 – 4.5 m|
|Coconut||9 m x 9 m|
|Tomatoes (Money maker)||100 x 50 cm|
|kales||60 x 60 cm|
Spacing determines plant population and the main aim of correct spacing is to obtain maximum number of plants per unit area which will make maximum use of environmental factors. Wider spacing leads to a reduced plant population which means lower yields, whereas closer spacing could lead to overcrowding of plants and competition for nutrients and other resources would occur. Correctly spaced crops produce yield of high quality that are acceptable in the market.
Spacing is determined by the following factors:
- The type of machinery to be used.
The space between the rows should allow free passage of the machinery which can be used in the field. For example, the spacing between rows of coffee is supposed to allow movement of tractor drawn implements.
- Soil fertility
A fertile soil can support high plant population. Therefore closer spacing is possible.
- The size of plant
Tall crop varieties require wider spacing while short varieties require closer spacing, for example, Kitale hybrid maize is widely spaced than Katumani maize.
- Moisture availability.
Areas with higher rainfall are capable of supporting a large number of plants hence closer spacing than areas of low rainfall.
- Use of crop.
Crop grown for the supply of forage or silage material is planted at a closer spacing than for grain production.
- Pest and diseases control.
When crops are properly spaced, pests might find it difficult to move from one place to the other, for example, aphids in groundnuts.
- Growth habit.
Spreading and tillering crop varieties require wider spacing than erect type.
Seed rate is the amount of seeds to be planted in a given unit area governed by ultimate crop stand which is desired. The objective of correct spacing of crop is to obtain the maximum yields from a unit area without sacrificing quality. Most crops are seeded at lighter rates under drier conditions than under wet or irrigated conditions. Seeds with low germination percentage are planted at higher rates than those which have about 100% germination percentage. There is an optimal seed rate for various crops. For example, the seed rate for maize is 22 kg per hectare, wheat is 110 kg per hectare and cotton is between 17 to 45 kg per hectare.
Factors to consider in choosing seed rates.
- Seed purity.
When planting seed which is pure or with a high germination percentage, less seed is required. On the contrary, more seeds are required when using impure or mixed seeds.
- Germination percentage.
Less seed is used when its germination percentage is higher. Seed of lower germination percentage is required in large amounts.
At closer spacing, more seeds are used than in a wider spacing.
- Number of seeds per hole.
When two or more seeds are planted per hole, higher seed rate is required than when only one seed is planted per hole.
- The purpose of the crop.
A crop to be used for silage making is spaced more closely than one meant for grain production. This would require use of more seeds. Maize to be used for silage making, for example, requires more seeds than that meant for production of grain.
Depth of planting.
This is the distance from the soil surface to where the seed is placed. The correct depth of planting is determined by:
- Soil type: seeds will emerge from grater depths in sandy soil that are lighter than in clay soils.
- Soil moisture content: It is recommended that one plants deep in dry soils in order to place the seeds in a zone with moist soil.
- Size of the seed: Larger seeds are planted deeper in the soil because they have enough food reserves to make them shoot and emerge through the soil to the surface.
- Type of germination: seeds with epigeal type of germination (carry cotyledons above the soil surface) such as beans, should be planted shallower than those with hypogeal type of germination (leave cotyledons under the soil) such as maize.
- Learners to carry out planting using broadcasting method and planting rows.
- Learners to identify different vegetative propagation materials displayed by the teacher.
- Learners to determine the correct plant population for a given area by mathematical calculations.
- Learners to collect samples of different tree seeds and prepare them for planting by various methods of breaking seed dormancy.
- Learners to determine the germination percentage of different samples of cereals and legume seeds.
Crop Production III
- Planting materials are either planted directly in a seedbed or indirectly through a nursery bed.
- A seedbed is a piece of land which could be small or large and prepared to receive planting materials.
- A nursery bed on the other hand is a small plot of land specially prepared for raising seedlings or planting materials before transplanting.
- It is usually 1m wide and any convenient length depending on the quantity of seedlings to be raised.
- A seedling bed is a special type of nursery bed used for raising seedlings pricked out from the nursery bed due to overcrowding before they are ready for transplanting.
- Pricking out refers to the removal of seedlings from a nursery bed to a seedling bed.
- Nursery practices refer to all the activities carried out throughout a nursery life to raise seedlings. .
Importance of Nursery Bed in Crop Production
- To facilitate the production of many seedlings in a small area.
- It is easy to carry out management practices in a nursery than in the seedbed.
- It facilitates the planting of small seeds which develop into strong seedlings that are easily transplanted.
- It ensures transplanting of only healthy and vigorous growing seedlings.
- It reduces the period taken by the crop in the field.
- Excess seedlings from the nursery may be sold to earn income.
Selection of a Nursery Site
Factors to consider;
- Nearness to the water source.
- Type of soil.-should be well drained, deep and fertile, preferably loam soil.
- Topography.-it should be situated on a gentle slope to prevent flooding and erosion through surface run-off.
- Previous cropping.-to avoid build up of pests and diseases associated with particular plant families, consider the preceding crops.
- Security.-select a site that is protected from theft and destruction by animals.
- Protection against strong winds and heat of the sun.-select a sheltered place. i.e. to avoid excessive evapotranspiration and uprooting seedlings.
Types of Nurseries
Categories of nurseries:
- Vegetable Nursery:
- They are used for raising the seedlings of vegetable crops.
- Tomatoes, cabbages, kale, onions, brinjals and peppers.
- Vegetable Propagation Nurseries:
- They are used for inducing root production in cuttings before they are transplanted,
- The cuttings can be planted directly in the soil and hence called bare root nurseries.
- Or planted into containers such as pots, polythene bags and others, hence called containerized nurseries.
- Tree Nurseries:
- These are used for raising tree seedlings.
- The seedlings can be raised in bare root nurseries or in containerized nurseries.
Nursery Management Practices:
- These are the practices carried out in the nursery while the planting materials are growing.
- Mulching. –light mulch should be applied on thenursery bed.It be should be removed on the 4th day
- Weed control.
- Pricking out.
- Pests and disease control.
- Hardening off
Preparation of vegetative materials for planting:
- Cuttings -These are plant parts such as stems, leaves and roots induced to produce roots and used as planting materials.
- Grafting –
- It is the practice of uniting two separate woody stems.
- The part bearing the roots is referred to as root stock while the part which is grafted onto the rootstock is known as
- The scion has buds which develop into the future plant.
- The ability of the rootstock and the scion to form a successful union is termed as
Methods of Grafting
- Whip or tongue grafting:
- In this case the diameter of the rootstock and the scion are the same.
- It is carried out when the diameter of the scion and the rootstock is ‘pencil’ thick.
- Side grafting: In this case the diameter of the rootstock is bigger than that
of the scion.
Other types of grafting include ;
- Approach grafting,
- Notch grafting
- Bark grafting.
- It is the practice of uniting a vegetative bud to a seedling of another plant.
- The scion has only one bud and some bark with or without wood.
- The bud is inserted in a slit made on the bark of the stock.
- It is held tightly on the stock by tying with a budding tape until it produces a shoot.
Methods of Budding:
- Top budding
- Patch budding.
Importance of Budding and Grafting:
- Plants with desirable root characteristics but with undesirable products may be used to produce desirable products for example lemon-orange graft.
- They facilitate the changing of the top of the tree from being undesirable to desirable
- They make it possible to grow more than one type of fruit or flower on the same plant.
- They help to propagate clones that cannot be propagated in any other way.
- They help to shorten the maturity period.
- It is the process by which a part of a plant is induced to produce roots while still attached to the mother plant.
- Once the roots have been produced, the stem is then cut off and planted.
Types of layering;
- Marcotting or aerial layering.
- Tip layering.
- Trench layering.
- Compound or serpentine.
Tissue Culture for Crop Propagation
- Tissue culture is a biotechnology used in cloning vegetatively propagated plants.
- It is based on the ability of plant tissue (or cells) to regenerate other parts of the plant.
- The tissues are derived from shoot tips where cells are undergoing rapid cell division and are not differentiated.
- The cells are then provided with the right conditions which enable them to multiply and develop roots.
The Right Conditions for tissue culture:
- Culture medium.
- Correct temperature.
- Correct light intensity and
- Correct relative humidity.
Importance of Tissue Culture in Crop Propagation
- It is used to recover and establish pathogen-free plants especially in the control of viral diseases.
- It is used in mass production of plantlets or propagules.
- It is fast and requires less space than the cultural methods of using cutting which requires a bigger space.
- Transplanting of vegetable and tree seedlings are generally the same.
- Generally, vegetable seedlings are ready for transplanting when they are one month old or have 4 -6 leaves or are about 10-15cm in height.
- Before transplanting, the nursery bed is adequately watered 3 – 4 hours before lifting the seedlings.
- This ensures the seedlings are lifted easily with a ball of earth around the roots to minimize root damage.
- Tree seedlings take a little longer to reach transplanting age compared to vegetable crop seedlings.
- The roots are trimmed before lifting the seedlings.
- Transplanting should be done at the onset of the long rains to give the young trees a good start.
- After transplanting the young trees should be protected from damage by animals for a period of about one year.
Crop production IV (Field Practices I)
- Field practices are activities carried out on the field to facilitate proper growth and maximum yield of the various crops grown.
They include the following:
- Crop Rotation
- R0uting field practices
- Crop protection
- This is the growing of different types on the same piece of land in different seasons, in an orderly sequence.
Importance of Crop Rotation
- Maximizes use of nutrients and moisture.
- Breaks the life cycle of pests and disease agents.
- Maintains good soil structure.
- Reduces soil erosion due to adequate soil cover.
- Controls weeds that are specific to certain crops e.g. striga on cereals
- Improves soil fertility when legumes are included in crop rotation.
Factors Influencing Rotational Programme
- Growth habits and nutrient req uirements.
- Liability to soil erosion.
- Crops attacked by the same pests and diseases should not follow one another in the programme.
- Availability of capital and market for example beans or peas in legumes.
- This is the placement of materials such as banana leaves or polythene sheets on the ground next to the growing crop.
- These materials should not come into contact with the base of the crop as they may encourage pest attack.
Importance of Mulching
- Reduction of evaporation rate.
- Smothers weeds.
- Moderation of soil temperature.
- Reduction of speed of run offs.
Types of Mulching Materials
- Organic mulching materials such as;
- Sawdust, wood shavings, coffee pulps, rice husks,
- Dry grass, banana leaves, dry maize stalk, napier grass.
- Inorganic or synthetic materials commonly used are either black or transparent polythene sheets.
Advantages of Mulching
- Prevents water evaporation thus maintaining moisture in the soil for crop use.
- Acts as an insulator thus modifying the soil temperature.
- It helps to control soil erosion.
- It controls weeds by suppressing them.
- After decomposition organic mulch add nutrients to the soil thus improving its fertility.
- Humus produced after the decomposition of organic mulch improves soil structure and the water holding capacity of the soil.
Disadvantages of Mulching
- It is a fire risk.
- Provides a breeding ground as well as a hiding place for pests that finally may attack the crops.
- Traps the light showers of rainfall thus lowering the chances of rain drops reaching the soil.
- It is expensive to acquire, transport and apply.
Routine Field Practices
- Removal of excess, weak, damaged or diseased seedlings.
- Allows the remaining seedlings to get enough nutrients and moisture.
- It is aimed at obtaining optimum plant population.
- Filling the gaps so as to maintain proper plant population.
- Gaps occur as a result of failure of seeds to germinate or dying of seedlings.
- It should be done early enough for the seedlings to catch up with the other plants
- This is the removal and destruction of a diseased part of a plant or the whole plant.
- The destruction can be achieved through burning of the uprooted plant.
- Removal of extra unwanted parts of the plant.
Reasons for pruning are:
- To remove old, unproductive or diseased, damaged parts of the plant.
- To train plants to take a desirable shape for example formative pruning in tea.
- To control crop leave ratio hence avoiding overbearing.
- To control diseases and pests for example antestia bugs in coffee.
- To facilitate other operations such as spraying, picking and seeding.
- To reduce wastage of chemicals applied on the crop.
- To remove branches that interfere with traffic, telephone lines and view.
- Open up the plant to allow free air circulation and exposure of leaves to sunlight.
Note: Tools used are secateur, pruning saw and pruning knife.
- This is the placement of soil in form of a heap around the base of the plant.
- It is mostly carried out in tuber crops such as Irish and sweet potatoes to improve tuber formation.
- It is also carried out in groundnuts and maize.
- In groundnuts it promotes production of pods while in maize it provides support to prevent lodging.
- Weeds are plants growing where they are not wanted, that is a plant out of place.
- Such plants include blackjack, couch grass, thorn apple and Mcdonald’s eye.
- Such plants should be eradicated or controlled using recommended methods.
- Crop pests are living organisms that are harmful to the crops.
- They include; insects, nematodes, rodents, thrips and mites.
- They cause great damage to crops in the field and stored produce.
Control of Crop Diseases
- A disease is any alteration in the state of an organism and functions of a plant or its parts.
- Disease causing organisms are known as pathogens.
- They include fungi, viruses and bacteria.
- Diseases caused by fungi are referred to as fungal diseases while those caused by viruses and bacteria are referred to as viral and bacterial respectively.
- It is the gathering or of the farm produce after maturity.
Time of harvesting depends on:
- Stage of maturity of the crops.
- Use of the crop.
- Tastes and preferences of consumers.
- Weather conditions, hence liability to spoilage.
Methods of harvesting is determined by:
- Scale of farming for example large scale farming machines are used.
- Type of crop for example pyrethrum is harvested by hand.
- Uniformity in ripening of the crop for example wheat is harvested by use of combined harvester while coffee is harvested by hand.
- Uniformity in height of the crop and size of seed, fruits and flowers.
- Financial status of the farmer.
- Part of the plant to be harvested.
- These are the preparations carried out on crop produce before it gets to the consumer. They include;
- Sorting and grading.
Purpose of storage is to;
- Prevent spoilage
- Make the produce available for future use
- To await good market prices.
Requirements for proper store are:
- It should be clean.
- It should be well ventilated.
- It should be raised from the ground to prevent damp conditions.
- It should be dry.
- It should be strong to hold crop produce.
- It should be easy to clean.
- It should be vermin-proof.
- It should be secure from theft.
- It should be treated against pests such as weevils.
Types of Storage
- Traditional storage structures.
- Modern storage structures.
Preparation of the Store
- Cleaning the store.
- Dusting the store with appropriate chemicals.
- Clearing the vegetation around the store to keep off vermin.
Crop Production V: (Vegetables)
- A vegetable is any crop that is grown and eaten fresh.
- Vegetables are important both for nutritional and commercial reasons.
- They are categorized on the basis of the part used as food.
- Such parts include;
Vegetables are grouped into the following categories:
- Leaf vegetables for example kales and cabbages.
- Root vegetables for example carrots, beets, radishes and turnips.
- Fruit vegetables for example French beans and okra.
- Stem vegetables for example asparagus, leeks and spring onions.
- Bulb vegetables for example bulbed onions and garlic.
Tomatoes (Lycopersicon esculentum)
- Tomatoes are fruit vegetables widely grown in Kenya.
- The ripe fruit may be eaten raw cooked or processed to make tomato sauces, juices and pastes.
- Altitude: 0-2100m above sea level.
- Rainfall: 7S0-1300mm per annum.
- Soils: deep, fertile and well drained.
- Fresh market varieties:
- Money maker,
- Marglobe, hundred fold,
- Beef eater,
- Hot set,
- Super marmande
- Processing varieties:
- Kenya beauty,
- San -marzano,
- Heinz 13S0,
- Rutgers hybrid
- Cal- J.
- Choose a site which has not been grown Solanaceae crop in the last three years.
- Nursery beds are raised about 15cm above the ground level.
- Make drills of 20cm apart and 1cm deep drill and cover the seeds.
- Provide shade or mulch material.
- Water twice a day.
- Apply phosphatic fertilizers during planting.
- The land should be dug deeply to control weeds.
- Seedlings are ready for transplanting when they are 10-15cmhigh after about one month.
- Holes are made at a spacing of 60cm x 90cm.
- Apply 20gm of DSP in the planting hole.
- Transplant with a ball of soil around the roots.
- Apply mulch around each seedling.
- Transplanting is normally in the evening or on a cloudy day.
- Early control of weeds is necessary.
- Top dressing is done after crop establishes.
- Pruning and staking are done to train the plants to grow vertically.
- American Bollworm
- Nature of damage: boring holes on the fruits.
- Control: spraying insecticides.
- Tobacco White Fly
- Nature of damage: suck plant sap from the underside of the leaf, hence may transmit viral diseases.
- Control: Destroy infected plant and spray insecticides.
- Late Blight
- Cause: Fungus
- Symptoms: dry patches on the leaves and fruits.
- Control: use of fungicides, crop rotation and destruction of affected materials.
- Blossom-end Rot
- Too much nitrogen in early stages.
- Irregular or infrequent watering.
- Calcium deficiency.
- Control: Apply calcium ammonium nitrate and correction of the above problems.
- For canning, fruits should be fully ripe.
- For fresh market, fruits should be partially ripe and packed in crates to avoid damage.
- The fruits should be graded according to;
- Freedom from blemishes.
- It is a leaf vegetable related to other brassica crops such as kales, cauliflower, Chinese cabbage and Brussels sprouts.
- Cabbage leaves may be eaten raw in salads, steamed, boiled or cooked in a variety of ways.
- The leaves can also be fed to livestock.
- Those with small heads: 900-1500m above sea level
- Those with Large heads: 1800-2700m above sea level.
- Temperature: require cool condition.
- 750-2000mm per annum.
- Should be well distributed throughout the growing period.
- Well drained.
- Early maturing:
- Sugar loaf,
- Early jersey,
- Copenhagen market,
- Chinese cabbage,
- Celery cabbage,
- Cafe splits kool
- Gloria, mukuki,
- Golden acre .
- Late maturing:
- The beds should be raised, dimension 1 m wide and any convenient length (usually 2-3m in length).
- Make drills of 15-20cm apart.
- Sow seeds by drilling and cover to a depth of 1 cm.
- Provide shade or mulch material.
- Apply phosphatic fertilizers and mix thoroughly with soil during planting.
- Water twice a day.
- Cultivation should be done during the dry season so that all the weeds are killed.
- Dig holes at the spacing of 60cm x 60cm.
- Incorporate farm yard manure in the soil.
- Water the seedlings before uprooting.
- Seedlings are ready for transplanting after one month that is when they are 1O-15cm in height.
- Select healthy and vigorous seedlings.
- Transplant the seedlings with balls of soil to prevent root damage.
- Plant to the same depth as they were in the nursery.
- Apply fertilizers during planting and top dress later.
- Control weeds to reduce competition.
- Diamond Black Moth
- Damage: Eats the underside of the leaf making windows or holes in the leaf.
- Control: Spray recommended insecticides.
- Damage: Attacks the stem at the ground level causing he plant to fall.
- Control: Spray recommended insecticides.
- Black Rot
- Cause: Bacteria
- Symptoms: Leaves turn yellow and rotting of the stem giving an offensive odour,
- Control: Closed season, crop rotation, use certified seeds and spray appropriate chemicals.
- Black Leg
- Cause: Fungus
- Symptoms: Brown to black spots on seedlings and dark canker on the stem.
- Control: crop rotation, destroy infected materials.
- Cabbages are ready for harvesting 3-4 months after transplanting.
- The heads are cut when they are solid and compact.
- Harvested cabbages are sold immediately.
Carrots (Daucus carota)
- It is a root vegetable grown in the cool areas of Kenya.
- It is commonly eaten raw in salads but can also be cooked.
- Altitude: 0-2,900m above sea level.
- 750 – 1,000mm.
- Well distributed throughout the growing period.
- It requires deep,
- Fine tilth
- Well drained soils that are free from obstacles to allow for root expansion.
- Temperatures: it requires cool to warm temperatures as very high temperatures result in the production of pale and short roots.
- Fresh market varieties for example Chantenay and Nantes.
- Canning varieties for example Nantes
- Fodder varieties for example Oxhast.
- The field should be well dug to a depth of about 20cm.
- The soil clods should be broken to give a fine tilth before planting.
- Manure should not be applied as it induces forking which reduces the crop quality.
- Carrots are planted directly into the main seedbed.
- Seeds are drilled into rows made 20-30cm apart.
- The seeds are then covered lightly and the soil pressed down.
- 90kg/ha of DSP should be applied at planting time in the drills.
- It should be mixed well with the soils before placing the seeds.
- Thinning — it is done 2 weeks after germination.
- Weed control– the field should be kept weed free.
- Earthing up should be done while weeding to encourage root expansion ..
- Topdressing: after weeding 60kg of nitrogen per hectare should be applied as top dress.
- Irrigation – this should be carried out where or when there is not enough rainfall.
- Carrots do not have many field pests except the green aphids.
- These can be controlled by use of the appropriate pesticides.
- Occasionally attached by the mildews especially in wet and humid environment.
- Thinning can be done to reduce humid conditions.
Harvesting and Marketing
- Carrots are ready for harvesting 3-5 months after planting depending on the variety.
- They are lifted from the soil and sold fresh or canned.
Onions (Allium cepa)
- Onions are bulb vegetables grown in the warm areas of Kenya.
- They are used as a vegetable in salads and for flavouring foods, soups and stews.
- Altitude: 0-2, 100m above sea level.
- 1,000mm of rain per year
- Irrigation in dry areas .
- Requires well drained fertile soils
- pH of 6.0 – 7.0 .
- Onions are a warm climate crops.
- However, some varieties prefer cool conditions.
- They require a fairly long dry period for ripening.
- Red creole,
- Tropicana hybrid
- White creole.
- The land should be well prepared leaving a fine tilth.
- Farm yard manure at 40 – 50 tonnes per hectare should be applied and mixed well with the soil.
- Direct: Seeds are drilled in rows 30cm apart and 8cm within the rows. 20kg/ha of DSP fertilizer is used.
- Indirect: Seeds are established in the nurseries before transplanting them in rows 30cm apart and 8 cm within the rows.
- Shallow planting is recommended for bulb expansion.
Field Management Practices
- It is carried out only in the crop that has been directly planted so as to achieve spacing of 8cm between two plants within the row.
- The thinned plants referred to as spring onions are used as vegetables in salads.
- Calcium ammonium nitrate at the rate of 250kg per hectare is recommended for topdressing onions.
- This is done 3 months after planting.
- These cause silvering and withering of leaves from the tips downwards.
- They are controlled by spraying with appropriate insecticides such as Diazinon or fenthion.
Purple Blotch and Downey Mildew
- Purple blotch;
- Characterized by oval greyish lesions with purple centres on leaves.
- This causes leaf curling and die back.
- Downey mildew;
- Characterized by brown spores covering the leaves leading to death of the whole plant.
- The two diseases are effectively controlled by crop rotation and application of appropriate fungicides.
Harvesting and Marketing
- Onions are ready for harvesting 5 months after planting.
- When leaves start drying the tops are broken or bent at the neck.
- This hastens the withering of the stems.
- The bulbs are then dug out and left to dry in a shade for a few days.
- Onions are graded according to size and marketed in nets of about 14 -16kgs.
Livestock Health I
(Introduction to Livestock Health)
- Health is the state of the body in which all the organs and systems are normal and functioning normally.
- Disease is any deviation from the normal health of the animal.
Importance of Keeping Livestock Healthy:
- Healthy animals give high income due to low treatment
- The productive life span of a healthy animal is longer.
- High production.
- Healthy animals can multiply regularly.
- Healthy animals give high quality products for example eggs.
- Safety of consumers of livestock products.
Predisposing Factors to Livestock Diseases
- These are conditions within or around the animal that make it easy for an animal to contract a disease.
- Animal factors such as;
- colour of the animal.
- Environmental factors such as;
- being rained on,
- exposure to hot sun
- Management factors such as;
- poor feeding,
- overcrowding .
Signs of ILL-Health in Livestock
- Abnormal behaviour for example separation from the rest of the herd and restle
- Abnormal posture for example limping and lameness.
- Alimentary canal disfunction such as blood stained faeces and abnormal defecation, diarrhoea and dysentery.
- Urination: high frequency or too low and having strange colour.
- Skin: rough with scaly skin, blisters on the skin and hair loss.
Causes of Diseases
- Pathogenic causes ;
- Physical causes;
- sprains .
- Nutritional disorders for example milk fever.
- Chemical causes for example poisoning by agrochemicals.
Categories of Diseases
- Notifiable diseases ;
- These are diseases which cause high economic losses.
- Any case should be reported to the Chiefs, D.O.s, veterinary officers or the police.
- Tick-borne diseases – Transmitted by ticks.
- Breeding diseases – Transmitted through mating.
- Nutritional diseases for example milk fever and bloat.
- Parasitic diseases for example ascariosis.
General Methods of Disease Control
- Control of vectors by use of acaricides and rotational grazing.
- Disinfecting the equipment and buildings.
- Use of preventive drugs.
- Proper feeding of livestock.
- Culling of the animals which are carriers/slaughtering the affected animals.
- Use of artificial insemination to control breeding diseases.
- Proper selection and breeding of animals.
- Proper housing and hygiene,
- Isolating sick animals.
Appropriate Methods of Handling Livestock
Animals are handled for the following reasons:
- When inspecting the animal to ascertain any abnormality or signs of diseases.
- When administering any form of treatment such as drenching, injection and mastitis control.
- When spraying or hand dressing the animal with chemicals to control external parasites.
- When milking the animal.
- When performing some of the management practices such as dehorning, disbudding, castration, hoof trimming .
When carrying out these activities animals should be restrained in a crush.
Other methods of restraining animals include the use of;
- bull ring
- lead stick.
Livestock Health II (Parasites)
- A parasite is an organism which obtains its livelihood from another organism (host) which suffers damage.
- Parasitism is the association between a parasite and a host.
The effects of parasite on the host animal are:
- Depriving the host of its food.
- Sucking blood.
- Damaging the organs of the host.
- Cause irritation on the skin of the host.
- Destruction of hides and skins.
- Transmission of diseases.
- Cause obstruction in body passages.
General Symptoms of Parasites Infestation:
- Pot bellied condition.
- Swellings in the jaw or other areas.
- Rough hair or rough coat.
- Presence of worm segments and blood stains in the defecat
Types of Parasites
There are two types of parasites:
- External (ecto-parasites)
- Internal (endo-parasites)
External parasites are;
- tsetse flies,
Life Cycle of ticks
- Eggs are laid in cracks on the grou
- They hatch in 4-6 weeks into larvae which climb on the grass waiting for a passing animal.
- This requires one host to complete its life cycle.
- Example: blue tick (Boophilus decoloratus).
- Preferred sites: face, neck, dewlap and side of the body.
- Disease transmitted: Redwater and anapl
- This requires two different hosts to complete its life cycl
- Example: The red legged tick (Rhipicephalus everts)
- Preferred sites: Ears, anus, udder and the tail.
- Disease transmitted: Redwater and east coast fever.
- Example: Bont legged tick (amblyomma spp.)
- Preferred sites: Udder, scrotum and tail switch.
- Disease transmitted: Sweating sickn
- This requires three hosts to complete its life cycl
- Example: The brown ear tick (Rhipicephalus appendiculatus)
- Preferred sites: Ears, tail switch and around the eyes.
- Disease transmitted: East coast fever and redwater.
- Bont tick transmit heartwater (amblyomma spp.)
Control of Ticks
- Dipping/spraying/hand dressing with acaricides.
- Rotational grazing.
- Ploughing the land to break the life cycle.
- Hand picking and killing.
- Fencing of the grazing fields to keep off other animals including wild game.
- Burning of grass to kill them in various stages.
Endo-parasites (internal Parasites)
- Endoparasites are helminths.
They can be divided into:
- Platyhelminthes/flatworms which include;
- Trematodes (flukes)
- Cestodes (tapeworms).
- Nemato-helminthes/nematodes. E.g Roundworms.
General Symptoms of Helminthiasis
- Diarrhoea which foul the anal and tail region.
- Big stomach (pot bellied condition).
- Presence of worm segments in faeces.
Trematodes (Liver Fluke)
- There are two species of flukes:
- Fasciola gigantica
- Fasciola hepatica.
- Fasciola hepatica is more common.
- It is commonly found in the liver and bile duct of cattle, sheep and goats.
- Liver fluke is a problem in marshy and low lying wet areas.
Life Cycle of the Liver Fluke
- Adult fluke in the liver of the primary host lays eggs.
- Eggs pass through the bile duct into the small intestines and are passed out in faeces onto the pasture.
- Under moist conditions, they hatch into a miracidium larva which swims about in search of a secondary host (fresh water snails).
- In the snail, it develops through sporocyst, redia and cercaria.
- When it leaves the snail, the cercaria gets encysted on vegetation and becomes metacercari
- This is swallowed by the primary host with grass.
- The young fluke migrates into the liver through blood vessels when it matures.
Control of Liver Fluke
- Keep livestock off marshy areas near the rivers/streams/lakes and dams.
- Drench affected animals.
- Drainage of swampy areas.
- Eradicate the intermediate host by use of molluscicides.
- Provide water to livestock in elevated troughs.
- There are many species of tapeworms
- Taenia solium
- Taenia saginata.
The adults live in the small intestines of man (the primary host).
- The intermediate host of Taenia solium is pig .
- The intermediate host of Taenia saginata is cattle.
Life Cycle of Tapeworm
- Adult tapeworms live in man’s intestines where it lays eggs.
- Eggs are passed out with faeces,
- Then they develop an outer covering known as onchosphere.
- The eggs are swallowed by intermediate host.
- The outer covering is digested and the young worm emerges.
- This bores into the blood vessels and is carried to specific muscles such as the tongue, heart, thigh muscles.
- It develops into an encysted form called bladder–worm.
- When the animal is killed and meat is eaten raw or in an inadequately cooked form, man gets infected by the bladder-worm.
- In man, the bladder-worm evaginates and attaches itself onto the intestinal wall where it develops into an adult.
Control of Tapeworms
- Meat should be well cooked before eating.
- Use of drugs in primary host.
- Meat inspection by meat inspectors/ veterinary officers.
- Use of pit latrines by man.
Common ones are;
- Ascaris suum (pig roundworms),
- Ascaris lumbricoides found in man and sheep
- Haemonchus contortus found in sheep, cattle and goats.
- Roundworms are common in warm areas especially in areas where the standards of hygiene and sanitation are low.
Nature of Damage
- Damage is done to the liver and lung tissues as they migrate in the body.
- Suck out blood.
- Deprive the host of food.
Control of Roundworms
- Use of drugs.
- Rotational grazing.
- Use of proper stocking rates to avoid overgrazing.
- Practicing high standards of cleanliness and hygiene such as use of latrines.
Livestock Production II (Nutrition)
- Animals are fed for the purpose of production and body maintenance.
- The edible material given to animals is called food.
- It is digested, absorbed and· utilized in the body.
- Nutrients are organic and inorganic substances contained in the food materials.
Components of Food material
- fats and oils,
- mineral salts.
- Free water (through drinking)
- Bound water (contained in feeds).
- Metabolic water (obtained from oxidation of food).
- Regulates body temperature.
- Transport agent in the body.
- Universal solvent in the body.
- Gives shape to the cells (turgidity).
- Acts as a lubricant.
- Acts as constituent of body fluids.
Factors Determining the Requirements of Water by Livestock
- Production level.
- Amount of dry matter eaten.
- Temperature of the surrounding area.
- Type of animal.
- Type of food eaten.
- Groundnut cakes,
- cotton seed cakes,
- fish meal,
- meat meal.
- Growth of new tissues.
- Repair of worn out tissues (body building).
- Synthesis of antibodies.
- Synthesis of hormones and enzymes.
- Production of energy during starvation.
Digestion of Proteins
In non-ruminants, protein digestion takes placed in the stomach.
- Food is subjected to mechanical breakdown through chewing into small particles.
- Protein is acted on by enzymes to turn into amino acid which is assimilated into the bloodstream.
In ruminants, protein digestion initially takes place in the rumen.
- Food is acted on by micro-organisms into microbial protein.
- Later, enzymatic action takes place in the “true stomach” or abomasum where proteins are broken down into amino acids which are then assimilated into the bloodstream.
- commercially mixed feeds.
- Supply energy and heat to the body.
- Excess is stored in form of fat for insulation of the body.
Digestion of Carbohydrates
- In non-ruminants;
- carbohydrate feeds are broken down by chewing into small particles.
- Then enzymatic action further breaks down carbohydrates into glucose, fructose and galactose which are then assimilated into the bloodstrea
- In ruminants;
- mechanical breakdown of carbohydrate feeds is followed by microbial activities which break down cellulose into volatile fatty acids.
- These are absorbed through the rumen walls.
- Some carbohydrates are broken down by enzymatic action in the “true stomach” or abomasum.
Fats and Oils
- Cotton seeds,
- soya beans
- Supply energy and heat to the body.
- Excess is stored as fat adipose tissues.
- Source of metabolic water in the body.
- Required for the development of neural system.
- Insulator in the body.
Digestion of lipids in Ruminants
- Fats are hydrolysed in the rumen into fatty acids and glycerol.
- Others are fermented into propionic acid,
- The shorter chains are passed to the true stomach where enzymatic action takes place.
- Green materials,
- dried grass
- fish liver oil.
- Protects the body against diseases.
- Regulate the functions of all parts of the body.
- It acts as a co-enzyme in the body.
- Vitamin A,
- vitamin B2
- vitamin C,
- vitamin E
- vitamin K.
- Salt licks,
- bone meal,
- Form part of the tissues such as bones and teeth.
- Work together with the enzymes.
- Act as acid -base balances.
- Act as electrolyte in the body.
- Regulate osmotic balance in the body.
- Calcium and phosphorus –
- Needed for teeth and bone formation.
- Lack of these minerals leads to rickets, osteomalacia.
- Lack of iron leads to anaemia.
Classification of Animal Feeds
This is based on nutrient composition:
- Feed additives.
- Are feeds of low available nutrients per unit weight and high fibre content.
- Dry roughages,
- succulent roughages,
- residues from agricultural by products and conserved materials.
- Low level of available nutrients.
- Have high level of calcium especially legumes.
- Good source of vitamin A.
- Have high fibre content.
- Are feeds of high available nutrients per unit weight.
- Maize germ and bran,
- malt extract,
- milk products,
- oil seed cakes,
- meat meal,
- Low fibre content.
- Feed content is consistently high.
- High digestibility of the feed.
- High in nutrient content.
These are substances added to the feed to increase;
- or hormones to make animals produce more.
There are two types:
- Nutritive additives, such as mineral licks (maclick).
- Non-nutritives additives, such as;
- medicants (coccidiostats),
- Stilboestrol (used in beef animals)
- oxytocin (to increase milk let down).
- Stimulate growth and production.
- Improve feed efficiency.
- Prevent disease causing organisms.
- These are the feeds prepared and mixed by use of machines.
- These feeds can be round, pelleted, pencils, cubes or mash.
Poultry feeds can be categorized as:
- Chick mash having 20% D.C. given to chicks.
- Growers mash having 16% D.C. given to growers.
- Layers mash having 12-15% D.C.P. given to layers.
Meaning of terms used to express feed values
- Nutritive ratio (NR):
- Is the proportion of protein to carbohydrates and fats.
- In young animals 1:3:6
- In old animals 1:8.
- Crude protein (C.P): Is the total amount of protein contained in a feed.
- Digestible Crude Protein (D.C.P): Is the portion of crude protein which an animal is capable of digesting.
- Crude Fibre (C.F.):
- Is the total amount of fibre contained in a feed.
- It is mainly lignin and cellulose.
- Digestible Fibre (D.F.): Is the portion of the total fibre contained in a feed which an animal is capable of digesting.
- Dry Matter (D.M.): Is the material left in a feed after water has been removed.
- Starch equivalent (S.E.): Is the amount of pure starch which has the same energy as 100kg of that feed.
- Total Digestible Nutrients (T.D.N.): Is the sum of all the digestible organic nutrients such as fats, proteins, carbohydrates and fibre.
Computation of Livestock Rations
- Is the amount of food that will provide essential nutrients to an animal in a 24 hour period
- to enable that animal to meet its maintenance and production requirements.
- Balanced ration:
- Is the ration that contains all the essential nutrients in required amounts and in the right proportion.
- Maintenance ration:
- is the portion of a feed required by an animal to continue with the vital body processes with no loss or gain in weight.
- Production ration:
- Is the feed required by animals over and above maintenance ration to enable the animal to produce;
- for example; milk, eggs, wool, grow in size, perform work, reproduce and fatten.
Steps in ration formulation
- Finding out the animal’s feed requirement based on body weight.
- List all the available feeds, with their nutrient composition and their prices.
- Calculate the amount of ingredients required in the ration to meet the animals needs.
Methods used in ration formulation
- Trial and error method
- Pearson’s square method
- Graphical method
- Linear programming(use of computers)
Mix a Pigs ration 22% protein using soya bean meal 40% DCP and maize meal containing 8%DCP.
Soya bean meal (14 *100)=43.75kg
Maize meal (18*100=56.25kg
Digestion and digestive systems
- Digestion is the process through which food is broken down into small particles in the alimentary canal ready for absorption into the blood stream.
Digestion of food in livestock takes place in three stages;
- Mechanical breakdown and chewing
- Microbial breakdown by bacteria and protozoa in the rumen of ruminants
- Chemical breakdown by enzymes.
- Breakdown of food by micro-organisms and also stores food.
- Synthesis of vitamin B-complex.
- Synthesis of amino acids from ammonia gas.
- Proteins are broken to peptides and amino acids.
- Carbohydrates are broken to volatile fatty acids.
- Separates large food particles from the small particles.
- Retains foreign materials such as stones, hard wood and sand.
- Breaks up food by grindin
- Reduction of water content from the feed stuff.
- Enzymatic digestion takes place here ..
- Contains some microbes which digest cellulose.
- Breaks up food by grinding.
- It is also found in non-ruminants.
Comparison Between Digestion in Ruminant and Non–ruminants
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Functions of the Parts of Poultry
- Storage of food.
- Softening of food by secretions from small glands in the walls.
- Proventriculus: Enzymes start the breakdown of food.
- Gizzard:-Crushes and grinds the coarse food (has small grit and gravel).
Comparison Between Digestion In Ruminants and Non–Ruminants
Similarities Between Digestion In Ruminants and Non–Ruminants
- Digestion in young ruminants is similar to that in non-ruminants as they do not have a developed rumen-reticulum complex.
- Final protein digestion takes place in the small intestines in both cases.
- Water absorption takes place in the colon in both ruminants and non ruminants
Livestock Production III…
(Selection and Breeding)
- The breeding of animals is under human control, and the breeders decide which individuals shall produce the next generation.
- The breeder makes a choice.
- The breeding of animals is based upon the fact that certain qualities are genetic ,hence valuable qualities are passed on from parents to off -springs.
- The qualities can be maintained or improved in the next generation.
The performance of an animal is influenced by two major factors;
- Genetic potential
- The environment, which includes:
- The ecological conditions.
- The genetic potential of an animal is inherited from its parents.
- In selection and breeding animals with superior characteristics are selected and allowed to mate.
- In the process they transmit the superior characteristics to their offspring.
- When this is done over a long period of time, it results in livestock improvement.
Reproduction and Reproductive Systems
- Reproduction is the process by which off-springs are produced.
- All farm animals multiply by means of sexual reproduction.
- It begins with fertilization which is the fusion of male and female gametes to form a zygote.
- Fertilization takes place internally in the body of the female.
- The embryo(zygote) formed develops inside body of mother, fed and protected until end of gestation period.
- In poultry, the process is different in that eggs are fertilized internally but laid and development of the chick takes place outside during incubation.
- In both male and female, certain organs are specialized for the process of reproduction.
- Some of these organs secret fluids which are necessary for the movement and survival of the gametes(reproductive cells.)
Reproduction in Cattle
- The male reproductive organs produce the male gametes,the spermatozoans.
- These are introduced into female reproductive system, where they fuse with the sperm to form zygote.
- The testis:
- There are two testes hanging loosely between hind legs.
- Enclosed by loose skin (scrotum)scrotum regulate temperature of testis for optimum production of sperms.
- Produce spermatozoa(sperms)which are stored in coiled tube called epididymis.
- Epididymis: Storage of spermatozoa.
- Sperm ducts:
- Conveys sperm from the testis and urine through the penis.
- sphincter muscles contract to allow each to pass separetly.
- Seminal vesicles produce fluid called semem.
- semen carries sperms out of penis in fluid form.
- Prostate gland -produce fluid that neutralize the acidic effects of urine in the urethra preventing death of sperms.
- Accessory glands: Include seminal vesicles cowpers gland and prostate gland.
- Urethra: Conveys urine and semen.
- Surrounded by a sheath which is an extension of skin.
- It introduces sperms into the vagina of a cow through the vulva during mating.
- It is a copulatory organ, also used for urination.
Ovaries and fallopian tubes(oviduct)
- Two ovaries located in abdomen, left and right.
- Produce ova/eggs and hormones which control sexual cycle.
- Oestrogen produced by graafian follicle inside ovary induces oestrus
- ie. Heat period so that the cow shows signs of heat
- After every 21 days the ovary releases a mature ovum and the cow comes on heat.
- The ovum travels through the fallopian tubes to the uterus.
- The release and movement of the ovum down to the uterus is called ovulation.
- If mating is done at this time, fertilization will take place.
- The fertilized egg implants itself onto the endometrium(walls of uterus)and develops into foetus.
- Fertilization takes place here.
- Also a passage for the egg from the ovary to the uterus.
- Embryo develops h
- The cervix: Closes the uterus.
The vagina and Vulva:
- Vulva is the external opening of female reproductive system.
- It allows mating to take place so that sperms are deposited into the vagina.
- The foetus and urine are removed through the vulva.
- Is period between fertilization of ova and the expulsion of the foetus through the vulva.
- Also called gestation period.
- In cattle gestation period is 270-285 days.
- Ends with the birth of a calf.
- The reproductive tract undergoes a period of rest during which it is repaired and returns to normal.
- During pregnancy, hormone called progesterone is produced by the placenta to maintain the foetus in the uterus.
- Act of giving birth called parturition.
- This time the foetus expelled through the birth canal.
When an animal is about to give birth, it shows signs;-
- Distended udder which produces thick milky fluid called colostrums.
- Swollen vulva producing thick mucus.
- Loose and slackened pelvic girdle.
- Visible pin bones.
- General restlessness.
- Animal parturates within 2-3 hours after this signs.
- The correct presentation is with the front feet first ,and the head outstretched and resting in between the fee.
- Any other presentation called mal-presentation or breech presentation and requires assistance.
Reproduction in Poultry
- The cock has no penis but a small opening near the vent through which sperms are emitted.
- Cock has testes within the body.
- The hen has elongated oviduct for formation of an egg.
- Fertilization occurs internally.
- During mating the cloaca of the hen and the vent of the cock fit into each other and then semen is poured into the cloaca ,then sucked to the oviducts.
The Reproductive System of a Hen
- Hen has two ovaries but one functional.
- Ova formed in ovaries.
- 3500-4000 ova present inside ovary held by follicle.
- Mature ovum released via rapture of follicle.
- It moves into oviduct received by the funnel.
- Fertilization occurs here.
- Chalazae also added to yolk.
- Time here is 15 minutes.
- It is 11.6cm long.
- Thick albumen is added.
- Stays for 3hrs.its 33cm long.
- Its 10.6cm long.
- Shell membranes added.
- Determines shape of egg.
- Water, mineral salts and vitamins added.
- Takes 15 minutes.
- Calcium deposited 9ie.shell added around the egg.
- Pigments added.
- Addition of albumin finished.
- Stays here for 18-22hours.
- Short, 6.9cm long.
- For temporal storage of egg before laying
- Egg moves out of cloaca through the vent.
- The cloaca extents out to prevent the egg from breaking.
- Egg formation not depended on fertilization.
- Egg formation takes 24-26hours.
- The components of egg are obtained from body reserves of the hens body.
Selection of a Breeding Stock
- Selection is used as a tool for livestock improvement.
- A breeding stock is a group of males and females which act as parents of future generations.
- Selection is the process of allowing certain animals to be parents of future generations while culling others.
- Culling is the removal of animals which do not perform to the desired level, from the herd.
- The animals retained have certain desirable characteristics which make them produce more.
- Selected animals make up the breeding stock.
- The breeding stock should pass the good qualities to their offsprings for better performance, to improve the livestock.
- Selection process repeated for many generations increases chances of formation of desirable qualities in an animal.
- Genetically termed as gene frequency(occurrence of the genes that carry desirable characteristics.)
- Selection increases occurrence of desirable genes and decreases occurance of undesirable genes.
- During selection, the characteristics to be selected for are first studied closely to ascertain that it is not influenced by the environment, but mainly by the genetic make-up.
- Selection helps improve characteristics which are highly heritable.
- Heritability means the likelihood of a particular trait to be transmitted to the offspring and they are strongly inherited.
- A character like milk yield is lowly heritable, i.e. it is weakly inherited and a bigger percentage of the character is affected by the environment.
The degree to which selection affects a character depends on the following factors;
- The heritability of the character
- The intensity with which the selection is done
- The interval between generations and kind of selection being practiced.
Factors To Consider When Selecting A Breeding Stock.
- Level of performance
- Physical Fitness
- Body Conformation
- Temperament or Behaviour
- Quality of products
- Mothering Ability
- Young animals,
- Those that have not parturated for more than 3-times, should be selected.
- They have a longer productive life.
- Old animals are poor breeders and low producers.
- Production and breeding efficiency decline with age.
- Level of performance
- Animals with highest production level selected.
- Performance best indicated by records.
Good performance of animal indicated by;
- High milk, wool and egg production,
- Good mothering ability
- High prepotency which is the ability of a parent to pass good qualities to their offsprings.
- The animals with poor performance should be culled.
- Good records kept and used by the farmer for this purpose.
- Physical Fitness
Animals selected should be free from any physical defect
- irregular number of teats,
- scrotal hernia,
- defective and weak backline
- Sick animals do not breed well and are expensive to keep.
- Animals that are resistant to diseases pass these characteristics to their offsprings
- Body Conformation
- Animals for breeding to be selected according to proper body conformation.
- A dairy cow should be wedge-shaped with a large udder, thin legs, long neck.
- Temperament or Behaviour
- Animals with bad behaviors should be culled.eg
- Cannibalism, egg eating, aggressiveness, kicking
- Quality of products
- Select animals that give products of high quality.
- Mothering Ability
- Animals selected should have a good mothering ability,
- That is animals with good natural instinct towards their young ones.
- This will enable them to rear the young ones up to weaning.
- Animals selected should be well adapted to the prevailing climatic condition in the area.
- Animals selected should be highly prolific.
- That is, animals with the ability to give birth to many offsprings at a time(larger litter).
- This is a quality that should be considered when selecting pigs and rabbits.
Selection in cattle, and sheep,
Selection in cattle
Consider the following;
- Level Of Performance Which Include;
- Milk Yield Buter Content.
- Length Of Lactation Period.
- Calving Intervals.
- Age Of The Animal,
- Physical Fitness,
- Health Of The Animal,
- Body Conformation,
- Suitability Of The Enterprise-Milk Or Beef
Selection in sheep
Consider the following;
- Level of performance which includes;
- Mothering ability
- Growth rate
- Wool quality
- Carcass quality
- Twining rate
- Suitability to the enterprise-wool or mutton
- Flocking instinct
- Health of the animal
- Physical fitness
- Inheritable defects
- Inheritable defects.
Selection in Goats
Consider the following:
- Mothering ability.
- Growth rate.
- Twining rate
- Carcass quality/dressing percentage.
- Growth rate.
- Suitability to the enterprise – milk or mutton.
- Health of the animal.
Selection in Pigs
- Consider the following:
- Carcass quality/dressing percentage.
- Suitability to the enterprise (bacon or pork)
- Growth rate.
- Health of the animal.
- Mothering ability.
- Number of teats.
- Body formation.
- Heredity defects
Selection in Camels
- Health of the animal.
- Foraging ability.
- Level of performance-milk, meat, fur and transport.
Method of Selection
- Mass selection – Animals with superior characteristics are selected from a herd and then allowed to mate among each other.
- Progeny testing – assessing on the breeding value of an animal on the basis of performance of its offsprings.
- Contemporary comparison -comparison of performance between heifers of the same age and sexual maturity.
- Process of mating selected males and females to produce offspring with the desired characteristics.
- To expand the inherited potential of the animal.
- To improve production.
- To overcome production problems created by the environment.
- To satisfy consumers taste.
- For economic reasons.
Terms Used in Breeding
- Genetic transmission of characteristics from parents to offsprings.
- The mechanism of inheritance is carried by the sex cells (gametes) and is controlled by genes found in the chromos
- Genes are very tiny units of inheritance carrying particular characteristics, such as colour, body shape and amount of milk production.
- Chromosomes are genetic materials which carry genes.
- They exist in pairs paternal and maternal) in the nucleus f the body cells.
- They are always constant in number.
Dominant and Recessive Characteristics
- A dominant gene is one that suppresses the othe
- It produces a dominant characteristi
- A recessive gene is one that is suppressed by the other.
- It produces a recessive characteristic.
Hybrid and Hybrid Vigour
- A hybrid is an animal which is the product of crossing animals of two different breeds.
- Hybrid vigour or heterosis is increased vigour and performance resulting from crossing two superior breed
- This is the masking of the effect of one gene by another gene which is non-allelic, that is situated on different locus.
- Mating of animals which are related. Reasons:
- To increase genetic uniformity in a herd.
- Used to fix the required characteristics in new breeds.
- To increase phenotypic u
- To get proven si
- It can bring about loss of hybrid vigour.
- It may lead to decline in fertility.
- It may lead to high rate of pre-natal mortality.
Systems of Inbreeding
- Close Breeding: mating between very closely related animals, for example sib-mating and parents sib-mating.
- Line Breeding: mating of distantly related animals that had a common ancestor for example cousins.
- Mating of animals which are not related.
- To introduce new genes in an existing breeding herd.
- To exploit heterosis resulting from a cross between two breeds.
- To develop a new breed or a grade animal.
- Lack of uniformity in animals that result from outbreeding.
- Desirable characteristics may be lost due to variation.
Systems of Outbreeding
Mating of animals from two different pure breeds.
Mating of unrelated animals from the same breed.
- Upgrading/Grading up
Mating where the female of a cow grade stock (locals) is mated with a pure breed sire.
The resultant animal is referred to as a high grade.
Mating in Livestock
Mating in Cattle
- Heat signs occur every 21 days.
- The heat period last for 18-30 hours on average 24 hours.
- Cow should be served 12-18 hours after showing the first heat signs.
- Mounting on others and when mounted on she stands still.
- Rise in body temperature.
- Drop in milk production in lactating cows.
- Vulva swells and becomes reddish.
- Clear or slimy mucus from the vulva.
- Bellowing or mooing frequently.
Mating in Pigs
- Heat signs in pigs occur after every 21 days.
- The heat lasts about 72 hours.
- Sows or gilts should be served in 18- 36 hours of the heat period.
Signs of Heat
- Frequent urination.
- Swelling and reddening of the vulva.
- Clear or slimy discharge from the vulva.
- Frequent mounting on others.
- It responds very well to the ‘riding test’.
Mating in Rabbits
- Does are ready for mating 6-7 months of age.
- Heat signs occur every 14 days.
- The doe should be taken to the buck and not vice versa.
Signs of Heat
- Frequent urination.
- Swollen vulva.
- The doe throws herself on the side.
- The doe rubs herself against the wall or any other solid object.
- The doe tries to contact other rabbits in the next hutch by peeping.
Methods of Service in Livestock
- It is more accurate.
- It is less laborious.
- Useful when heat signs of females cannot be easily detected.
- Inbreeding is not easily controlled.
- Transmission of breeding diseases.
- Extra feed for the male is required.
- Large males can injure small females.
- Wastage of semen.
- It is cumbersome and expensive to transport a bull to remote areas.
- Introduction of semen into the female reproductive tract by artificial means.
- There is economical use of semen.
- It controls transmission of breeding diseases.
- Sires that are unable to serve cows due to heavy weight or injury can produce semen to serve cows.
- It prevents large bulls from injuring small cows.
- It reduces the expenses of keeping a male animal.
- A small scale farmer who cannot afford to buy a superior bull can have the cows served at a low cost.
- Semen can be stored for long.
- It helps to control inbreeding.
- It eliminates the threat of keeping dangerous bulls from the farm.
- It makes research work easier.
- Harmful characteristics can be spread quickly by one bull to the offsprings.
- It requires skilled labour.
- Low chance of conception due to death of semen during storage.
- It is laborious:
- It is the implantation of an embryo (fertilized ova) from a high quality female (donor) in the uterus of a low grade female (recipient).
- Faster multiplication of an animal with superior characteristics .
- It is easier to transport embryos than the whole animal.
- Embryos can be stored for a long period awaiting the availability by recipient females.
- It stimulates milk production in a female (recipient) that was not ready to produce milk.
- Low grade animals can be used in production and rearing of high quality animals.
- Offsprings of a superior female can spread quickly in an area.
- It is expensive.
- It requires skilled personnel.
- It requires special equipment for fertilization and storage of embryos.
Signs of Parturition in Livestock
- Parturition is the act of giving birth in female animals.
Parturition in Cattle
- The gestation period in cattle is 270-285 days averaging 280days.
Signs of Parturition
- Enlarged or swollen vulva.
- Clear mucus discharge from the vulva.
- Slackening of the pelvic muscles.
- Full and distended udder.
- Thick milky fluid from the teats.
- A water bag appears and bursts just before calving.
Parturition in Pigs
- The gestation period in pigs is about 4 months or 3 months, 3 weeks and 3 days.
Signs of Parturition
- The vulva turns red and swells.
- The udder becomes full with a milky fluid the sow starts to prepare a nest by collecting some beddings at one comer of the pen.
Parturition in Rabbits
- The gestation period in rabbits is 28-32 days.
Signs of Parturition
- Preparing a nest by plucking off hair from her belly.
- Goes off feeding
- The udder distends.
Livestock Production IV
(Livestock Rearing Practice)
- In the management of livestock there are many activities that are carried out on animals to enhance production.
- They require care in feeding, health, breeding.
- Specific management also important in bee and fish farming.
Routing livestock rearing practices.
- A routine is a fixed/regular way of doing something.
- done repeatedly after a certain period of time
- Animals are fed to cater for both maintenance and production requirements.
- These are special types of feeding carried out on certain animals to cater for specific needs.
- The practice of giving extra quality feed to an animal around service time.
- In sheep it is done 2-3 weeks before tupping and 3 weeks after tupping.
- In pigs it is done 3-4 weeks before service.
Importance of Flushing
- It increases conception rates.
- It enhances implantation of the zy
- In sheep it increases twinning percentage by 15-20%.
- Giving extra quality feed to an animal during the last weeks of gestation.
- In cattle it is done 6-8 weeks before calving.
Importance Steaming Up
- It provides nutrients for maximum foetal growth.
- It helps in the build up of energy for parturition.
- It ensures the birth of a healthy animal.
- It promotes good health of the mother.
- It increases and maintains high milk yield after birth.
- Feeding of young animals from birth to weaning.
- 10 days old – introduced to creep pellets.
- 5 weeks old – creep pellets mixed with sow and weaner meals.
- 8 weeks old – weaning.
- Run with their mothers for natural suckling.
- Bucks – introduced to succulent feeds and concentrates.
- Meat goats kids suckle naturally.
- Dairy goats, fed on milk artificially,
- Given 0.5-1.25 litres up to the third week.
- Introduced to concentrates at 3-4 months.
- Weaned at 6-8 weeks of age.
Parasite and Disease Control Practices
- Introducing active disease organsms which are reduced in strength or virulent into the animals’ body to induce immunity.
Administration of Vaccination done through:
- By injection.
- Orally through the mouth.
- By inhalation through the nose.
- Eye drops.
- Practice of killing/removing internal parasites by administering drugs known as dewormers / antihelmitics.
- Cutting back overgrown hooves with the help of a hoof trimming knife, a hoof cutter or a hoof rasp.
- Facilitate easy movement.
- Control of foot rot disease.
- Facilitate mating – prevent the ram from injuring the ewe during tupping.
- This is the removal (cutting oft) of tails in sheep during the first week after birth.
- Even distribution of body fat.
- Facilitate easy mating in adult life.
- Minimise fouling of the wool with faeces.
- Reduce incidences of blowfly infestation.
Methods of Docking /tailing
- Cutting with sharp knife or scalpel.
- Use of elastrator and rubber ring.
Dipping and Spraying
- These are methods of applying acaricides on the animals to control external parasites.
- It is the application of chemical powders on the animal body or on the walls of the animal house to control external parasites.
- It is used to control stick-fast parasites and fleas in poultry.
These are practices carried out to enhance successful breeding.
- Crutching and Ringing
- Crutching – cutting of wool around the external reproductive organs of female sheep.
- Ringing – trimming wool around the sheath of the penis of the rams to facilitate mating.
- Tupping and Serving
- Tupping refers to mating in sheep and goats.
- Serving refers to mating in cattle and pigs.
- This is the practice of fitting the rams with breeding chutes which are painted in different colours during mating
- to identify mated ewes and to indicate the active rams hence help in culling of the weak rams.
The practice of putting identification marks on animal.
- Branding – burning marks on the animals skin.
- Ear tagging – placing marked plastic or metallic tags on the animals ears.
- Ear notching – cutting different shapes bearing different values on the ear lobes.
- Tattooing – use of permanent ink or dye to mark animals with light skin.
- Neck strap or chain – Fixing of tags round the animals neck with a chain or a strap.
Importance/ purpose of Identification
- record keeping
- Setting disputes in case animals get mixed up in the pasture.
- Cutting about 1/3 of the upper beak with a knife, scissors or hot iron.
- Control egg eating.
- Control cannibalism.
- The removal (clipping) of the needle (canine) teeth in piglets 24 hours after birth.
- Removal of undesirable animals from a herd.
- Removal of horns or horn buds from an animal.
- It prevents animals from injuring each other.
- It makes the animal docile and therefore easy to han
- For easy transportation and feeding.
- Prevents destruction of farm structures.
- The practice of cutting wool from all over the body of a sheep.
- It starts at the age of 8 months and then done once a year.
- Should be done during the dry season.
- Tools used: wool shears.
- Care must be taken not to cut the skin, testicles, udder, vulva and penis.
- It is the rendering unserviceable the testicles of a male animal.
- To control breeding diseases.
- To control breeding.
- For faster growth rates.
- Increase quality of meat by removing unpleasant smell especially in goats.
- Closed/bloodless method
- involves use of burdizzo or rubber ring and ela
- Animals do not bleed but may not be 100% effecti
- Open method
- A surgical method used for castrating cocks, piglets and rabbits whose testes are internal.
- Also used for lambs, kids and calves.
- Animals bleed a lot.
- However, it is 100% effective.
- It is not recommended for mature adults.
- It is the practice of making male birds lose their male characteristics by use of hormones.
- Hormones used include stilboestrol which is injected into the birds when they are one day old and female hormones implanted beneath the skin at the neck.
- Birds which have lost their male characteristics in this way are referred to as capons.
Management During Parturition
- Parturition is the act of giving birth to fully grown foetus.
Parturition in Cattle
- It is referred to as calving.
- Gestation period lasts 270-285 days after conception.
- When the signs of parturition are observed the cow should be separated from the rest of the herd.
- Normal calving should take 2 hours and the normal presentation is the muzzle, face or fore head on top of the forelegs first.
- In case of other presentations the mother should be assisted.
- Provide the mother with plenty of water and feed after par
- If the after birth does not come out within 48 hours a veterinarian should be called to remove it.
Parturition in Sheep
- It is referred to as lambing.
- Gestation lasts 21 weeks (150 days) after conception.
- The ewe lamb naturally without any problem.
- If complications arise the ewes should be assisted.
Signs of Parturition in Sheep
- Udder becomes full.
- Teats are bright red in colour.
- Restlessness and bleating.
- Slackening of the hip muscles.
After these signs ‘are seen the ewes should be separated from the others.
- The normal presentation is forelegs and head first.
- After birth the mother should be allowed to lick the lamb to ensure the coat is dry.
Parturition in Goats
- It is referred to as kidding.
- It takes place 150 days after conception.
- Nannies carrying twins, kid a few days earlier.
- Kidding nannies should be kept in a clean dry place which should be well sheltered.
- Signs of parturition are similar to those of ewes.
- Kidding nannies should be kept with another female for company.
Parturition in Pigs
- It is referred to as farrowing.
- Gestation period 113-117 days ( 4 months).
Signs of Farrowing
- The sow becomes restless.
- There is enlargement of the vulva .
- Muscles on each side of the tail slacken.
- There is loss of appetite.
- The udder and the teats become enlarged.
- The sow collects bedding material in one comer to build a nest.
- Milk present in the teats 24 hours before farrowing.
After the signs are seen;
- Farrowing takes about 2-6 hours under normal conditio
- An attendant should be there to assist the mother and piglets.
- Ensure the removal of the after birth to prevent the sow from eating it.
- The sow should be fed well and given plenty of clean water.
Parturition in Rabbits
- It is referred to as kindling.
- It takes place 28-32 days after conception.
- Provide a nesting box and plenty of dry soft beddings in the hutch towards the fourth week of gestation .
Signs of Parturition
- The doe plucks off the fur from her body.
- Uses the fur to build a nest about 3-10 days earlier.
Bee Keeping (Apiculture)
- Bees are insects which live in very well organised colonies.
Each colony consists of:
- Queens – fertile females that breed to ensure the continuity of the species.
- Drones – fertile males that mate with the queen for reproduction process.
- Workers – non-fertile or sterile females that maintain the colony.
Duties of Workers
- They rear and nurse the brood (eggs, larvae and pupae), queen and drones.
- They collect nectar and make honey.
- They make the honey combs.
- They protect the hives.
- They clean the hive.
Importance of Bees
- Collect nectar from flowers.
- Make honey – a nutritious product used by man as food.
- Helps in crops pollination of plants.
- Bees produce wax used to make candles.
- They make propolis – a bee product which is medicinal.
Siting/locating of an Apiary
Factors to consider;
- Nearness or accessibility to nectar or flower-producing vegetation.
- Areas with shade. Bees are sensitive to the sun’s heat and require some shade to protect them.
- Safe distance from human residence and other livestock.
- Bees are stinging insects and can be a hazard to humans or other animals.
- Nearness to a source of water for use in their nutrition.
- A good distance from source of noise and other disturbances.
- Safety from predators for example honey badgers, ants (safari ants), birds and other parasites such as wax moths.
- Normally bees are self-sufficient in providing their food from the honey they make.
- However, during the dry season, their feeding should be supplemented by providing a solution (syrup) of sugar water or giving molasses.
- This should be placed strategically so that it is easily accessible to the bees.
- Wax moths
- Bee louse
- Honey badger
Control of Parasites
- Use of physical barriers such as Vaseline/grease to control ants.
- Smoke the hive to control bee louse.
- Suspend the hive to control honey badgers.
- Burn infected combs to control wax moths.
Diseases and Control
- African bees are seldom attacked by diseases.
Factors to consider;
- Stage of ripening: Honey must be harvested when it is fully matu
- Season of the year: Harvested at the end of the rainy season.
- Blow light smoke through the hole.
- This makes bees suck honey and become engorged and docile.
- Lower the hive to the ground.
- Open the hive to expose honey combs.
- Brush the bees off the honey combs.
- Cut the honey combs, leaving a small margin on the bars and keep them in a closed container.
- Using heat in a water bath to melt the honey.
- Crushing and straining.
- Using a centrifugal extractor.
Precautions When Handling Bees
- Avoid excessive smoking.
- This kills the brood and lowers quality of the honey.
- Use protective clothing to avoid sting.
- Protect the hive from rain water.
- Use clean equipment and containers to avoid contamination of the honey.
- Use recommended method of extracting honey.
- Use recommended type of hive such as Kenya top bar hive.
Fish Keeping (Aquaculture)
- The rearing or keeping of fish is called fish farming and is normally carried out in specially prepared ponds.
A good fish–pond should have the following features:
- Site should be on a fairly level ground with a permanent supply or source of water.
- The area should have clayey soil to avoid loss of water through seepage.
- Water must be free from any pollutants such as chemicals and other wastes.
Construction should provide for:
- an inlet for fresh supply of water,
- a spill way channel to take off overflow or excess water,
- an outlet to drain off the water when it is necessary to replace pond water,
- a fence to keep off predators and other intruders.
- Fish naturally feed on worms, insects and algae in the ponds.
These sources of food must be supplemented by throwing in the pond ;
- kitchen wastes,
- chopped vegetable materials such as cabbage leaves,
- cereal brans
- brewers’ grain .
Management Practices to Ensure Maximum Harvest of Fish
- Control of stocking rate, that is to, have the recommended population of fish in a pond at anyone time.
- Harvest at the correct maturity stage.
- This is done by using the fishing net with correct mesh sizes to avoid catching the fingerlings.
- Avoid water pollution in the ponds which may poison fish.
- Ensure adequate supply of food in the pond.
- Water in the ponds should be kept in motion to facilitate aeration.
- Maintain appropriate depth (level) of water.
- Control predators and/or thieves.
- Drain and refill ponds with fresh water as necessary.
- Harvesting or extracting fish from the fish ponds for consumption
Two main methods:
- Hook–and–line method:
- This is slow, injures small fish and is inefficient.
- It is only suitable for small-scale fishing.
- Use of fishing nets:
- This is the most efficient method as long as a net with the correct mesh sizes is used.
- Harvesting may be done 6-8 months after the introduction of fingerlings into the fish pond.
Maintenance of the Fish Pond
- Repairing the dyke or any structure on it.
- Cleaning the pond and removing foreign materials.
- Planting grass where necessary.
- Removing un desirable vegetation.
- Removing the silt.
Practices before preservation:
- Clean the fish to remove mud and any worms.
- Removing scales and slime.
- Opening the fish on the side to remove the gut and the intestines referred to as gutting. .
- Cleaning the abdominal cavity thoroughly.
- Keeping fish in open containers.
Methods of Preservation
- Sun drying
Appropriate Handling of Livestock During Management
- Physical beating should be avoided.
- Structures which help in restraining animals should be used whenever applicable.
- The correct methods of securing and casting animals should be used.
- Use as little force as possible.
- Equipment such as ropes, halters, lead stick and bull rings are used to handle animals appropriately.
- Farm structures are physical constructions on the farm used to increase efficiency in production.
Construction of Farm Structures
Planning for farm structures ;
- Farm activities.
- Size of the enterprise.
- Future of the enterprise.
- Soil type.
Siting farm structures;
- The location of the homestead.
- Wind direction.
- Relationship between the structures.
- Proximity to social amenities.
- Farmer’s taste and preference.
Materials for Construction
Structural Materials and Use
Factors which determine the type of materials to use are;
Stones and Bricks
- Stones and bricks are durable, easy to disinfect, resistant to weather and insects decay and are easily available.
- They are bulky and require skilled labour to make them.
Plastic and Synthetic Materials
- asbestos fibre
- polythene materials.
- cheep depending on quality,
- easy to disinfect,
- can be moulded into any shape,
- are durable,
- cannot be destroyed by insects and fungus
- are water-proof.
- Are easily destroyed,
- very expensive
- require skilled labour.
- They are workable,
- can be re-used
- are fairly strong.
- They can catch fire easily,
- decay if exposed to water
- are affected by fungus and insects.
- Is a mixture of cement, sand, aggregate and water
- e.g. in making blocks the ratio is 1:2:3; one part cement, two parts sand and three parts aggregate.
- Making posts for fencing.
- Making walls and floor of buildings.
- Making gabions and water channels to prevent erosion.
- Making water troughs.
These materials are;
- durable, workable,
- easy to disinfect,
- cheap to maintain,
- fire resistant
- These materials are ;
- require skilled labour,
- cannot be reused
Animal handling structures
- The crush –used when doing following activities;
- Spraying livestock to control ticks,
- examining sick animals,
- artificial insemination,
- treating animals, eg drenching, vaccination,
- dong routine jobs such as dehorning, identification marks,
- The spray race-used in the control of ticks by spraying livestock with acaricides
- The dip- machakos type, and the pludge dip. This is used in the control of ticks by dipping livestock
Factors to be considered in site selection;
- Nearness to a source of water
- Direction of the prevailing wind
- Direction of the sun
- Personal whims/tastes and preference
- Nearness to means of communication.
Types of farm buildings
- Houses for farm animals.
- Stores for farm produce.
- Stores for equipment, tools and supplies.
- Buildings for growing crops e.g green house.
- Building for processing plant e.g milk plant.
Parts of a building
- The foundation,
- The walls,
- The roof
- tie beam,
- rafter batten
- concrete floor,
- foundation wall,
- PVC sheet (damp-proof course)
- the compacted fill (hard core).
- Importance of Fence in a Farm
- Keep out intruders to the farm,
- Define the boundary lines of the farm.
- Paddocking of fields to make rotational grazing possible.
- Live fences serve as windbreaks.
- Fences are used in mixed farming to protect crops from. damage by livestock.
- Fences add aesthetic values to the farm.
- It is easy to control breeding.
- It is easy to isolate sick animals from the rest of the herd.
Types of Fences
- Dead fences.
- Barbed wire fences.
- Electric fence.
- Concrete fence.
- Chicken wire fence (mesh wire fence).
- Woven wire fence (chain link).
- Wooden fence.
- Materials include;
- concrete materials.
- Size of posts:
- General purpose 2.5m by 25cm in diameter
- Strainer units and corner posts 3m by 30cm in diameter:
- Distance between the posts:
- 3m between posts, 10m if droppers are to be used.
- 200m between strainer units.
- Depth of holes – 60cm.
Gate Posts, Gates and Strainer Units
- Gates should be hung on posts separate from the fence.
- Mechanical implements for example tractors require 4.0-4.5m width of gate.
- Entrance gates for pedestrians can be accommodated within the fence.
Steps in Fencing
- Locate the corners
- Clear the fencing area.
- Mark gates, strainers, pass places and standards by pegging.
- Dig holes to proper depths.
- Fix the standard posts.
- Firm around posts or apply concrete.
- Fix wires on posts.
- Fix the droppers.
Agricultural Economics II
(Land Tenure and Land Reforms)
- Land is an important factor of production.
- Without land it is impossible to practice the agricultural business.
- However the efficiency of utilization of land is influenced to a large extent by the condition of holding the land.
- Land tenure is defined as the possession of the legal rights to the use of land.
- Various kinds of rights to the use of land give rise to different tenure systems.
Land Tenure System
- All land tenure systems fall into two major classes, namely:
Collective Tenure Systems
Communal Tenure Systems
- This involves the possession of rights over land by the whole community.
- It works quite well under conditions of unlimited, land res
Advantages of Communal Tenure
- Landless problem does not exist.
- Land is not fragmented.
- Allows for free movement of animals in search of better pastures and water.
- Promotes community spirit among the members.
Disadvantages of Communal Tenure
- No incentive among the users to conserve the land resources.
- Everybody strives to maximize returns from the land without the drive to invest, for example, in terms of soil conservation and maintenance of soil fertility.
- There is a tendency of overstocking and continuous cropping; which leads to soil erosion and loss of land productivity.
- As a result of communal grazing of livestock, it is impossible to improve livestock through;
- controlled breeding,
- proper feeding,
- disease and parasite control.
- Since there is no title deed, (certificate of ownership) it is virtually impossible to secure loans to develop the land.
Co-operative Tenure System
- This category includes various collective arrangements under the government or other authorities.
- Farmers voluntarily group together and buy land which they subsequently operate on co-operative basis.
- Examples are co-operative ranches.
Advantages of Co-operative Tenure
- No land disputes.
- Labour is well utilized.
- Profit is distributed according to the number of shares.
- Resource use is enhanced for high production.
Disadvantages of co-operative tenure.
- Incase of poor management everybody will loose.
- No individual title deed hence cannot secure loans.
- Land is owned by the whole state and is refered to as government land.
Examples in Kenya;
- Areas not allocated to individuals
- Land under local county councils/cities and towns
- Land under forest, game reserve and parks, land for infra-structure and public utility
Advantages of state ownership
- Generation of income for the state
- All the citizens benefit from whatever comes out of the land.
- Non-competitive in terms of production
- No individual motivation when working on the land.
Individual Tenure system
The various forms of individual land tenure are;
- Owner operator,
- Plantation and Concestion,
- This category includes all persons who operate on land to which they have absolute individual rights.
- Examples are the majority of individual land owners in areas where demarcation and registration of land has taken place and title deeds issued.
- The owner is free to make permanent production plans.
- The owner can pledge the land title deed to secure loans(credit) from lending agencies for further development
- An individual is motivated to work harder than when under communal arrangement
- Managerial failures usually affect small units of production and are therefore negligible.
- It is easy for the owner to get agricultural advice.
- Cost such as machinery for processing may be too high for the individual owner
- Innovation may be inadequate due to low levels of education.
- Lack of capital to invest.
Plantation and concession
- In this form of land tenure, the individual is usually a company or a corporation.
- Most of them engage in the production of only one commodity
- They are rigid in their production plans and in most cases labour is hired on wage basis.
- Example are coffee, tea, sugarcane, sisal estates in Kenya.
- High production from the land hence high economic gains
- Allows foreigners to use and develop land
- No land disputes
- Create employment for the local people
- Generate government revenue through taxation.
- Individuals own large pieces of land while others are landless
- Large areas of land may be left underdeveloped.
- Foreigners may repatriate profit to their countries.
Landlordism and tenancy
- The arrangement here involves the ownership of land by one individual or group of individuals (landlord) who lease it to another individual (tenant).
- A legal lease specifies the length of time during which the tenure is operative;
and that serves as a security of tenure to the tenant.
- The efficiency of production in this arrangement is greatly affected by the length of lease, its legal backing and rent payable.
- A person without land can get a chance to use land.
- A landlord who cannot operate the land, for any reason, can still earn income by leasing it to a needy tenant.
- It is a flexible arrangement; that is, it allows room for change of production plans should need arise.
- Security of tenure gives the tenant incentive to invest depending on the length of tenure.
- Poor land use and low production if the tenant does not have enough funds to improve on land.
- Tenants cannot produce long term crops,
- Landlords can exploit the tenants by overcharging.
- Lack of incentives to improve land by the tenants since it does not belong to them.
- Land reform is any organized action designed to improve the structure of land tenure and land use.
Forms of Land Reform
- This means bringing or putting together, into one piece; fragmented parcels or pieces of land scattered over a large area.
The objective of land consolidation are :
- To save on time spent while moving from one piece of land to another.
- To facilitate effective and efficient farm planning.
- To create an incentive among land operators to invest on and develop land.
- To facilitate mechanization and improve production through efficiency.
- To improve level of production through effective supervision of the labour force and sound farming methods,
Land Fragmentation and Sub-division
- This is the subdividing of a (large) piece of land into smaller portions.
- Sometimes it becomes necessary to sub-divide land for the following reasons:
- To sell part of the land.
- The parent may wish to subdivide and distribute his land among the sons, daughters and other dependants.
- The government may decide to subdivide large farms in order to settle landless citizens.
Land Adjudication and Registration
- Land adjudication involves;
- Establishing the legitimate ownership,
- Measurements (to make permanent boundaries)
- Recording of land details.
- Once land has been adjudicated, and any disputes concerning the same land are settled,
- It is then registered in the “Register of Land”.
- And the owner is issued with a land title deed or certificate of legal ownership.
Importance of land title deed
- The legal owner of the land has security of tenure and hence an incentive to invest and improve productivity.
- A farmer can mortgage the land by offering land title certificate as a security to loaning agencies to secure capital to finance development projects.
- If a farmer who cannot operate the farm, he can still earn income from it by leasing it.
- Disputes concerning land boundaries and/or land ownership no longer arise.
Land Settlement and Resettlement
- Land settlement means the occupation of land which was previously uninhabited.
- Land resettlement, on the other hand, is the transfer of people from an already densely populated area to a sparsely populated one.
- To settle the landless citizens.
- To relieve population pressure in densely populated areas.
- To increase or promote agricultural productivity by farming on land that was previously unused or lying idle.
- To create self-employment thus improving the living standards.
- Land reclamation, especially by creating tsetse fly-barriers.
Soil and Water Conservation
- Soil and water are two very important natural resources in farming.
- They should therefore be well maintained and used without wastage to sustain continuous production.
- Water loss during the rainy season should be prevented and excess water conserved for use during scarcity.
- Soil erosion must be controlled at whatever cost if soil is to be conserved.
- It is the removal and carrying away of the top soil by the action of water or wind.
Factors Influencing Soil Erosion
- Amount and intensity of rainfall.
- The steeper the land the higher the velocity of surface runof
- The higher the velocity of surface runoff the greater is its erosive power/effect.
- Type of soil for example sandy soils are more easily detached and carried away than clayey soil
- Soil depth;
- The deeper the soil, the longer it takes to be saturated with
- Land use:
- Overstocking leads to bareness of the land and looseness of the soil.
- Deforestation – indiscriminate removal of trees leads to exposure of soil to heavy rainfall and high te
- Indiscriminate burning of vegetation exposes the soil to erosive agents.
- Clean weeding leaves the soil bare.
- Ploughing along the slope.
- Monoculture or continuous cultivation.
- Ground cover
- Trees act as windbreakers.
- Roots of vegetation cover hold the soil particles together.
- Leaf fall act as mulch which reduces erosion.
- Leaves of vegetation cover intercepts raindrops reducing their erosive power.
Agents of Erosion
- Water – moving water has erosive power.
- Wind – wind carries away soil.
- Human beings – through man’s activities such as cultivation and mining.
- Animals – through overgrazing and creating footpaths where soil erosion takes place.
Types of Erosion
- Raindrop (splash) – displacement of the soil caused by raindrops.
- Sheet – uniform removal of soil in thin layers from flat or gently sloping areas.
- Rill – removal of soil from small bur well defined channels or rills.
- Gulley – removal of soil from channels which become progressively deeper and wide
- Riverbank Erosion – removal of soil along river banks by the river water.
- Solifluction – gravitational flow of soil saturated with wa
- Land slides – mass movement of rock debris and soil down a slope,
- Slip movement of earth or rock masses for a short distance.
- Debris slide – materials move at a greater speed.
- Debris fall – movement of materials/debris along vertical cliff.
- Rock fall – movement of rock down a very steep slope.
- Rock slides – mass of rock materials that slide along a bedding plate, a joint or a fault face.
Soil Erosion Control Measures
Soil conservation measures can be classified into:
- Biological or cultural control
- Physical or structural control
Biological or Cultural Control Measures
These measures are applicable where land slope is between 2-12%.
- Grass strips/filter strips;
- These are narrow uncultivated strips along the contour left between cultivated strips.
- Cover cropping ;
- The establishment of a crop that spreads out over the surface of the soil to provide it with a cover.
- Contour farming ;
- Carrying out all land operations along the contour.
- Mulching ;
- Covering of the soil with either organic or synthetic materials.
- Proper cropping systems such as:
- Crop rotation
- Correct spacing
- Strip cropping
- Controlled grazing;
- Proper stocking rate, rotational grazing.
- Strip cropping;
- Growing crops which give little ground cover in alternate strips with crops such as beans which have a good ground cover.
- Afforestation – growing of trees where non-existed.
- Re-afforestation – growing of trees where they have been cut down.
- Agroforestry – land use that involves the growing of trees in combination with crops and pastures on the same piece of land.
Physical or Structural Control Measures
- These are soil and water conservation measures which involve mechanical constructions on the earth.
- They are used in areas of moderate slope between 13-55%.
- Trash or stone lines;
- These are rows of heaped crop’ residues or stones made along the
- Filter strips;
- It involves the growing of an open crop in the upper side of the slope followed by a dense crop to reduce speed of wate
- This increases infiltration.
- Are structures constructed across a slope to reduce the length of a slope thus reducing run-off.
- Bench terraces;
- Are constructed where the slope is 35-55%.
- Tree crops are suitable for such areas.
Importance of a Bench Terrace: –
- Reduces slope of the land.
- Conserves soil moisture.
- Better retention of soil fertility.
- Narrow based terraces –Cannot allow cultivation by machines.
- Broad based terraces – Is wide enough to allow cultivation by machines.
- Graded terraces:
- Have a drainage channel to lead off excess water to a vegetated plac
- They should be about 100m in length.
- Level terraces:
- Have no outlet channels,
- The aim is to have water infiltrating,
- Hence no water can flow from the ends of the terr
- Fanya juu:
- A ridge made by digging a channel and throwing the soil uphill.
- Fanya chini:
- In this case the soil is heaped on the lower side of the channel.
- Bunds: heaps of soil (earth) made along the contour.
- Cutoff drains:
- An open trench with an embankment on the lower side into which water from the farm dra
Water from the trench should be discharged into;
- Natural waterways,
- Artificial waterways,
- Rocky ground
- Gabion/Porous dams:
- Galvanized wire mesh boxes filled with stones which are built across slopes and gullie
- Dams and reservoirs ;
- Dams – barriers built across a river/waterway to hold and store water. It reduces speed of runoff.
- Reservoirs – these are large storage ta
- Ridging – heaps of soil to reduce the speed of water,
They retain the water for some time.
Water Harvesting Methods
- Water harvesting and storage should be done during the rainy seasons to avoid wastage.
This should be done using the following methods:
- Roof catchment – trapping and collection of rain water from roof tops.
- Rock catchment – water is harvested by constructing a barrier on the lower side of a large impervious rock to trap surface runoff from the rock.
- Weirs and dams.
- Dam – a barrier constructed across a river or a dry valley so that it can hold water.
- Weirs – barriers constructed across a river or a stream to raise the water level and still allow water to flow over it.
- Ponds – water retention excavations’ made to hold excess surface water.
- Retention ditches/level terraces.-These are terraces constructed with blocked ends to retain water.
- A system of harvesting limited rainfall and storing the water in the ground for use by the planted crops.
Types of Microcatchments;
- V-shaped bunds measuring 25cm
- Are built with soil from the excavated planting holes to direct runoff water towards the basin area around the base of each plant
- Semi–circular bunds;
- Formed around the growing plant to hold water around the plant.
- Trapezoidal bunds;
- Trapezoidal shaped bunds, which enclose a large area where the crops are grown.
- Contour bunds/furrows ;
- These are furrows made along the contours between the rows of crops where agroforestry trees are intercropped with annual cro
- Planting holes/pits ;
- These are extra large planting holes made and filled with dry plant materials before filling in with soil.
Use of Micro-Catchments
- Slow down the speed of surface runoff.
- Used during landscaping of the compound, parks and roadside nest areas.
- Reclamation of land for food crop in dry areas.
- Water collected and stored can be used for irrigation
- Afforestation in dry areas.
Weeds and Weed Control
- Weeds cause heavy crop losses if not controlled.
- Their control is important so as to maintain high quality and quantity produce.
- A weed is any plant growing where it is not required.
- And whose economic disadvantages outweigh the advantages.
Harmful Effects of Weeds
- Weeds compete with crops for nutrients, space, light and soil moisture.
- Some weeds, for example, Striga spp are parasitic to cultivated crops such as maize.
- Some weeds lower the quality of agricultural produce for example:
- Mexican marigold gives undesirable flavour to milk if dairy cows feed on it.
- Devils horsewhip, black jack, bristly fox-tail and others get attached to sheep wool thus lowering its quality.
- Some weeds are poisonous to human beings and livestock for example:
- Thorn apple (Datura stramonium)
- Sodom apple (Solanum incanum)
- Some weeds have allelopathic effects to cultivated crops.
- Water weeds block irrigation channels.
- Aquatic weeds such as Salvinia in Lake Naivasha and water hyacinth in Lake Victoria affect fishing.
- Some weeds are alternate hosts for insects, pests and disease causing organisms for example:
- Wild oat (avena fatua) is an alternate host for rusts.
- Mallow (malva verticillata) is an alternate host for cotton stainers.
- Weeds lower the quality of pasture for example:
- Tickberry (Lantana camara)
- Nut grass (Cyperus rotundus),
- Manyatta grass (Eleusine jaegeri)
- Some weeds irritate workers thus reducing the efficiency in which they are controlled for example:
- Double thorn (Oxygonum sinuatum),
- Stinging nettle (Urtica massaica) ,
- Devil’s horse whip (Achyranthes aspera).
Factors Contributing to the Competitive Ability of Weeds
- They produce large quantities of seeds for example pigweed and black jack.
- Their seeds remain viable in the soil for a long time awaiting conducive germination conditions.
- They have effective seed dispersal mechanisms.
- Some weeds propagate by means of elaborate underground storage structures.
- They are efficient in utilizing little moisture, nutrients and sunlight.
- Some have short life cycles.
- They have elaborate root systems for supporting the plant and absorbing nutrients and water.
It is based on:
- Life cycles for example:
- Annuals – complete their life cycle in only one season.
- Biennuals – complete their life cycles in two seasons o
- Perennials – complete their life cycle in more than two seasons.
- Morphology – leaf formation such as size, shape and venation.
- Broad leaved weeds for example black jack, lantana, pig weed, oxalis and others.
- Narrow leaved weeds for example couch grass, setaria, nut-grass, manyatta grass and others.
- Habitat – some weeds are terrestrial (grow on land) while others are aquatic (grow on aquatic/marine conditions).
- Weeds are identified by their common (individual) names and botanical names.
- They are named according to specific features or according to person who identified them.
Common Name Botanical Name
- Black Jack ………………………Bidens pilosa
- Mexican marigold ………………Tagetes minuta
- 0xalislsorrel ……………………..Oxalis spp.
- Double thorn ……………………Oxygonum sinuatum
- Thorn apple ……………………..Datura stramonium
- Couch grass ……………………..Digitaria scalarum
- Nut grass ………………………..Cyperus rotundus
- Wandering Jew …………………Commelina bengalensis
- Sow thistle ………………………Sonchus ole race us
- Devil’s horsewhip ……………….Achyranthes aspera
- Macdonald’s eye/ Gallant soldier. Gallinsoga parviflora
- Sodom apple …………………….Solanum incanum
- Black night shade ………………..Solanum nigrum
- Chinese lantern…………………. Nicandra physalodes
- Bracken fern ……………………..Pteridium aquillium
- Love grass/ Bristly foxtail ……….Setaria verticillata
- Cleavers …………………………Gallium spurium
- Stinging Nettle …………………..Urtica massaica
- Fat hen/Goose foot ………………Chenopodium spp.
- Rape weed ………………………Brassica nap us
- Wild oats …………………………Avena fatua
- Lantana/Tick berry ………………Lantana camara
- Water hyacinth ………………….Eichhornia crassipes
- Striga/Witch weed ………………Striga hermontheca
- Creeping indigo ………………….Indigofera spicata
Weed Control Methods
The methods of weed control determined by:
- The weed being controlled.
- Weather conditions.
- Capital availability.
- Effect on environment.
METHODS OF WEED CONTROL INCLUDE:
Chemical Weed Control –
- The use of chemicals known as herbicides to control weed
Classification of Herbicides
- Formulation – the physical form of the herbicides for example:
- Wettable powders
- Time of Application
- Pre-emergence – applied before the planted crop germinates.
- Post emergence – applied after the planted crop germinates.
- Non selective.
- Mode of Action
- Contact – herbicides that kill only the parts of the plant which it comes into contact.
- Translocated systemic herbicides that will kill the whole plant even if it comes into contact with only a small part of it.
Methods of Herbicide Application
- Spraying – application of solutions.
- Dusting – application of dusts.
- Fumigation – application of fumigants into the soil.
Safety Measures in the Use of Chemicals
- Read manufacturer’s instructions and follow them.
- Wear protective clothing such as overalls, breathing mask, gloves and boots.
- Avoid inhaling the herbicides.
- Wash thoroughly after handling chemicals.
- Do not blow or such blocked nozzles.
- Avoid herbicide drift to unintended crops and other plants.
- Avoid herbicide drift to livestock feed and water.
- Avoid spilling herbicides in pastures and fodder crops.
- Dispose off the empty containers properly for example burying them in the soil.
- Do not wash spraying equipment in water sources used by animals and human beings.
- Store chemicals in a safe place.
- Wash the spraying equipment thoroughly.
- Sink left over chemicals into the soil after the day’s work.
Advantages of Chemical Weed Control
- It is less laborious.
- Effective in the control of difficult weeds such as couch grass and sedges.
- It does not disturb crop roots and other underground structures.
- It makes the control of weeds in certain crop easier.
- It is efficient in both wet and dry conditions.
- It does not destroy soil structure.
- Cheaper in large scale production than the use of manual or mechanical cultivation.
Disadvantages of Chemical Weed Control
- It requires skilled labour in mixing and application.
- Cause environmental pollution.
- Herbicides have long residual effects which may interfere with future crops.
- It is very expensive.
Mechanical Weed Control
- It involves the following operations:
- This is the opening and loosening up of the soil.
- It can be done by hand tools or tractor drawn implements.
- Cheap in small scale production.
- Increases water and air infiltration into the soil.
- Incorporates crops residues into the soil.
- The earthing-up done during tillage encourages root growth.
- If done repeatedly it destroys soil structure.
- It is laborious and expensive in large scale production.
- It may not effectively control weeds.
- It may lead to soil erosion and loss of soil moisture.
- Damage crop roots.
- Mechanical removal of shoots from weeds.
- It is effective in the control of annual weeds.
- It is done when the crops are too close
- To allow mechanical cultivation or where weeds are scattered.
Cultural Weed Control
It involves the following practices:
- Cover cropping.
- Crop rotation.
- Timely planting.
- Use of clean seed/planting materials.
- Proper spacing.
- Proper seedbed preparation.
Biological Weed Control
- The use of living organisms to control weeds.
- Use of livestock to graze and control growth of weeds especially in plantations.
- Use of weed eating fish to control aquatic weeds.
- Use of moths to control cactus.
- Limitations: the method is not reliable.
Legislative Weed Control/ Quarantine
- It involves government laws and regulations which prevent the introduction and spread of foreign weeds in a country or an area. Done by KEPHIS.
- Limitations: Only samples are checked while the bulk of the materials may have some weed seeds.
Crop Pests and Diseases
- Crop pests and diseases lead to high losses in crop production hence efficient control measures are
- Proper control measures require the farmers to be able to;
- Identify these organisms,
- Know their life cycles, feeding habits
- The damage they cause to crops.
Definition of a Pest:
- It is a living organism that destroys crops/ trees either directly or indirectly by introducing pathogens (disease causing germs).
Classification of Pests
Pests are classified according to the following:
- Mode of Feeding
- Pests with biting and chewing mouth parts – they cause physical damage and reduce the photosynthetic area of the plant.
- Pests with piercing and sucking mouth parts – they suck out the nutritious plant sap and in the process may introduce disease causing organisms.
- Crops Attacked
- Some crop pests attack specific crops for example, stem borers prefer cereal crops.
- Stage of Growth of Crops Attacked
- There are pests of seedlings attack when the crop is young, for example cutworms.
- Pests of fruits – attack the crops at fruiting stage.
- Pests of grains attack the crops when the grains are formed.
- Field and Storage Pests
- Some pests attack the crops while in the f
- Other pests attack the produce after it has been harvested and stored.
Identification of Common Pests
|Name of Pest||Crop Attacked||Damage Done||Control Measures|
|Armyworms||(i)||Cereal crops||Defoliate the||(i) Early planting|
|(Spodoptera||(ii)||Sugar cane||whole plant||(ii) Use of effective insecticides|
|Cut worms||Young seedlings||Cut the seedlings||(i) Early planting|
|(Agrotis Spp.)||at the stem base||(ii) Use of soil applied insecticides|
|Boll worms||Cotton, tomatoes,||Eat and destroy||(i) Crop rotation|
|(Heliathis migera)||citrus, maize,||the fruits and||(ii) Field hygiene|
|beans, millet, other||seeds||(iii) Spraying with insecticides|
|legumes||(iv) early planting|
|Maize stalk borer||Maize sorghum||Destruction of the||(i) Early planting|
|(Busseola fusca)||stem and young||(ii) Field hygiene|
|and||growing tissues||(iii) Crop rotation|
|(Chilo partellus)||(iv) Use of stalk borer dust.|
|Loopers||Coffee||Make windows in||(i) Use of effective insecticides.|
|(Ascotis selena ria)||crop leaves||(ii) Use of parasitic wasps, birds|
|Leaf Miner||Coffee||Make mines in||(i)||Use of parasitic wasps (natural|
|( Leucoptera||the leaves||enemies)|
|meyricki and L.||reducing||(ii) Use of effective insecticides.|
|Stainers||Cotton||Stain the cotton||(i)||Use of parasitic tachinid flies|
|(Dysdercus spp.)||lint reducing||(ii)||Spraying with insecticides.|
|quality||(iii)||Control alternate hosts.|
|Aphids||Several crops such||(i) Transmit||(i)||Natural enemies for example,|
|(Aphis spp.)||as citrus, maize,||viral diseases.||lady birds|
|cotton, beans.||(ii) Suck out||(ii) Overhead irrigation|
|cabbages and||sap leading||(iii) Use of insecticides|
Other Crop Pests Include:
- Mealy bugs – coffee
- Thrips – coffee
- Beetles – field and storage pests.
- Birds – field pests – cereals and fru
- Rodents – field and storage pests ,cereals and t
- Nematodes – soil borne pests – tomatoes, potatoes, sunflower, beans.
Harmful Effects of Crop Pests
- Pests such as squirrels and rodents, unearth planted seeds, resulting in poor
- Some pests like nematodes, termites and moles damage crop roots causing wilting and death of the crops.
- They lower the quality and quantity of farm produce.
- They increase the cost of production since farmers will incur expenses in purchasing chemicals to control them.
- They transmit diseases to crops for example, aphids transmit streak virus disease in maize.
- Chemicals used to control the pests cause pollution to the environment.
- They exterminate the crop by feeding on them for example eating embryo of the seed.
Control of Pests
- If pest population causes damage beyond tolerance then it is said to have reached economic injury level (EIL) hence control measures should be effected before this level.
Before any control measure is effected ,the following should be considered:
- Know the life cycle of the pest.
- Correct identification of the pest.
- Correct assessment of the damage.
- The weather conditions.
- The value of the crop in question.
- The cost factor of the control method.
Methods of Controlling the Pests
- Cultural methods.
- Physical/mechanical measures
- Biological methods.
- Chemical methods.
- Integrated pest management.
- These are farming practices which aim at reducing the pest population by destroying the life cycle of the pests either by exposing them to adverse conditions or denying them food.
- Timely planting to escape pest attack.
- Timely harvesting.
- Proper tillage.
- Close season: this is the period when a susceptible crop is not grown in order to control a certain pest.
- Trap cropping: These are crops which attract pests diverting them from the main crop. The trap crop is grown together with the main crop.
- Crop rotation: It breaks the life cycle of the pest.
- Planting resistant varieties: These are plants with natural protective mechanisms against pest for example hairy cotton against jassid bugs, goose necked sorghum against birds, high tillering in sorghum against shoot fly.
- Field hygiene: This includes rogueing and removal of crop residues which harbour pests from field.
- Alterations of environmental conditions, such as, creating a microclimate which is not conducive to pests for example open pruning in coffee.
- Crop nutrition: application of fertilizers and manures to make the crop strong and able to escape pest attacks.
- Destruction of alternate hosts, for example, weeds like mallow which harbour cotton stainers.
- Use of clean planting materials. This helps to prevent introduction of crop pests.
- Proper spacing: if well spaced some pests find it difficult to move from one plant to another.
- Use of organic manure, for example, farmyard manure discourages eel worms (nematodes).
- Chemicals used to control pests are known as pesticides.
- Pesticides are administered through dusting, spraying or fumigating.
Classification of Pesticides:
Pesticides are classified on the basis of:
Mode of Entry
- Stomach – ingested by the pest together with the crop materials.
- Contact – absorbed through the body tissues.
- Fumigants – through the breathing mechanism.
- Systemic – translocated to all parts.
Mode of Action
- Respiratory poisons – interfere with breathing mechanisms.
- Coagulants – cause the blood of the pest to coagulate.
- Neurotoxins – act on the nervous system.
- Protoplasmic poisons – cause the cells to disintegrate.
- Insecticides – kill insect pests
- Molluscicides – kill snails and slugs.
- Rodenticides – kill rodents.
- Nematocides – kill nematodes.
- Dusts, granules and powders
- Emulsifiable concentrates.
- Miscible liquids.
- Wettable powders.
Factors That Affect the Efficiency of Pesticides
- Concentration of the pesticides.
- Weather conditions at the time of application.
- Timing of application – efficiency is high if applied when the pest is most susceptible.
- Persistence of the pesticide having long residual effect in the soil.
- Resistance of the pests.
Advantages of Chemical Pest Control
- Immediate results are achieved.
- Low labour requirements.
Disadvantages of Chemical Pest Control
- Expensive to buy.
- Cause pollution to the environment.
- Require skilled labour to apply.
- Some pesticides may kill beneficial organisms and predators.
- Some target pests may build up resistance.
Mechanical Pest Control/Physical
- This involves the killing of the pests using physical methods.
- Or creating physical barriers to prevent pests from getting into contact with the crops .
- Flooding/irrigation; for example, moles are suffocated through flooding.
- Use of lethal temperatures: either too cold or too hot.
- Suffocation; commonly used in grain storage bins by being made air tight.
- Trapping and killing, for example, rats.
- Creation of physical barriers, such as, rat bafflers, sticky materials on tree trunks.
- Proper drying: this makes them too hard to be destroyed by pests.
- Scaring devices especially in rice plantations to control birds.
- Use of explosives thrown at breeding places of birds to kill or scare them away.
Biological Pest Control
- It involves the use of living organisms to reduce the pest population.
Predator Target Pest
- Parasitic wasp——————-White fly in citrus, boll worms, stalk borers
- Birds——————————— Crickets, locusts, caterpillar llars.
- Lady Bird ————————–Aphids
- Trachnid flies ——————-cotton stainer
- Praying mantis—————–giant loppers
- Majimoto ants —————–scales
- Cats ———————————-moles,rats,mice
- Brachonid wasps————-mealy bugs
- Chicken —————cotton stainer, larvae of beetles, grasshoppers, crickets
- No environmental pollution
- Saves on labour.
- Takes too long to get the correct agent
- Difficult to control the pest effectively.
Integrated Pest Management
- It is a new method which involves the combination of the methods mentioned above.
- The aim is to have least hazards to the user and to the environment.
- Example, attractant-pheromones are used to attract pests to one place where they are sprayed and eradicated.
- Legislative mearsures of pest control are effected by the Kenya Plant Health Inspectorate Service(KEPHIS) through seed inspection.
Crop Disease And Their Control
- A disease is any deviation from the normal performance or functions.
- A plant disease is any harmful physiological disorder in a plant caused by pathogenic agents such as virus, bacteria, fungi.
- The study of plant disease is called plant pathology.
Economic importance of crop diseases
- They lower crop yield
- They reduce the quality of the produce thus reducing their market value
- They cause food poisoning. E.g ergot in wheat, afflatoxin in grain crops by fungus.
- They reduce photosynthetic area of the plant.
Classification and identification of plant disease
- Plant disease are classified according to their causal agents;
- Fungi are non-green plant-like.
- Some are parasitic and others are saprophytic.
Parasitic fungi divided into;
- Obligate parasites- those that depend on other living organisms for food.
- Falcultative parasites-those that are able to live on both the living and dead tissues.
Examples of fungal disease
- Panama disease(Fusarium oxysperium—bananas)
- Cigar-end rot(Verticilium theobromae)-bananas
- Die back –attack the tips of shoots and roots
- Mildews-foliar disease of several crops
- Armillaria root rot(Armillaria mellea)-coffee and tea
- Damping off-disease of seedlings in the nursery
- Anthracnose (Colletotrichum spp)-coffee,beans,tomatoes.
- Fungus also cause damage to stored grains which are not properly dried or if the store is damp.
- Fungus cause food poisoning and lower seed viability for example Aspergillus flavus which produces a highly toxic compound called afflatoxin.
Examples of fungal disease
|Disease/cause||Crops attacked||Symptoms of attack||Control measures|
|Dry patches on the leaves and fruits (necrotic lesions)||-Crop rotation
|Rusts (Pucinia spp)||Rice, wheat , sorghum, maize||Red and brown pistules on the leaves, shriveled grains||-resistant varieties
|Smuts(Ustilago spp)||Wheat, maize ,
|Black powder mass on the spikes and the ear||-Field hygiene,
|Blasts(Piricularia oryzae)||Rice||-Small blue sports on leaves with grey centre.
-Attack inflorescence to cause ‘’empty heads’’
-Resistant varieties eg sindano
-Destruction of affected plants
|Coffee Berry Disease(CBD) (Colletotrichum coffeanum)||Coffee||-Dark blotches spots on the flowers
-Brown concentric rings on the leaves
-Dark sunken wounds on the berries.
|-Resistant varieties eg Ruiru 11
- Bacteria are microscopic single-celled organisms which reproduce by binary fission
- Transmission; Through irrigation water, seeds, fertilizers, manures, wind ,
- raindrop splash, insects, soil and mechanical means.
Symptoms of Bacterial Diseases
- Cankers(necrotic tissues)localized necrosis
- Gall formation in infected tissues.
Examples of bacterial diseases
|Disease/Cause||Crops Attacked||Symptoms of Attack||Control Measures|
|Halo blight||Beans||i. Irregular dark lesions on||1.||Use of resistant varieties|
|(Pseudomonas||leaves and pods.||for example Wairimu.||,|
|phaseolicola)||ii. Yellow band round the||ii. Effective fungicide.|
|lesions called “halo”.||iii. Crop rotation|
|iii. Water soaked lesions|
|Fusarium wilt||Tomatoes||l.||Stunted growth.||i. Use of resistant varieties.|
|(Fusarium||ii. Yellowing and shedding|
|iii. Wilting of the plant.|
|Black arm||Cotton||i. Small round spots on the||i. Field hygiene.|
|(Anthomonas||cotyledons of young||ii. Use of certified seeds.|
|ii. The spots elongate to|
|form black lesions on the|
|Bacterial wilt||Tomatoes and||Uniform. wilting of the whole||i. Use of certified seeds.|
|(Pseudomonas||potatoes||plant even with enough||ii. Crop rotation.|
- Viruses are small living organisms which can only be seen under a very powerful electronic microscope.
- Viruses interfere with photosynthesis, respiration, transpiration and nitrogen utilization
Symptoms of Viral Infection
- Leaf chlorosis.
- Leaf curling.
- Mosaic(light green or yellow patches).
- Malformation(distortion)of plant parts.
- Rosettes; Development of abnormally short internode.
- Through the use of infected vegetative materials and insect vectors like aphids, mealybugs and leafhoppers.
|Disease/Cause||crops Attacked||Symptoms of Attack||Control Measures|
|Ratton stunting||Sugar cane||Red discoloration on the vascular||I.||Use of clean materials.|
|bundles.||11.||Treatment of seed|
|Maize streak||Maize||Yellow stripes alternating with||i.||Control leaf hopper.|
|green, parallel to the midrib.||ii. Use if certified seeds.|
|iii. Field sanitation.|
|Greening||Citrus||i. Yellow mottling of the leaves.||i, Use of clean tools when|
|iii. Premature leaf fall.||11.||Control of insect vectors.|
|Leaf mosaic||Suzgar cane,||i. Yellow mottling.||i.||Control of aphids.|
|cassava. sweet||II.||Necrosis of stem.||ii. Use of clean materials.|
|Tristeza||Citrus||I.||Dwarfing of plants.||i. Stripping affected fruits.|
|ii.||Die back.||ii. Use of clean equipment|
Other Causes of Crop Diseases
- Flooding forming ammonia which is poisonous to the crops causing a burning effect on leaves.
- Chemicals: some may be toxic.
- Poor weather: Extremes of day and night temperatures.
- Stress: such as irregular watering as in tomato blossom end rot.
Control of Crop Diseases
- Cultural method: This involves use of
- Healthy planting materials.
- Practicing field hygiene.
- Proper seedbed preparation.
- Proper spacing.
- Heat treatment of the planting materials for example sugar cane.
- Proper drying of cereals and pulses to 13%M.C.
- Growing disease resistant varieties.
- Involves the imposing of regulations and laws especially in case of disease outbreaks to prevent the introduction and spread of diseases.
- Used as a last resort.
Chemical control measures include:
- Seed dressing before planting.
- Soil fumigation to control soil borne diseases.
- Spraying: application of fungicides.
Crop Production VI
(Field Practices II)
- There are many crops cultivated in Kenya.
- These crops are grown for various uses and require different ecological conditions.
- Hybrids – These are crop varieties developed by crossing two pure lines.
- Composites – These are crop varieties developed through repeated mass selection.
- Cultivars – these are varieties of crops which are cultivated in a given area.
- Main growing areas: Trans-Nzoia, Nakuru, Uasin Gishu, Laikipia districts and others.
- Ecological Requirements
- Altitude: Upto 2000m above sea level.
- Temperature: About 25°C
- Soils: Freely draining, fertile loam soils.
- Rainfall: 750-12S0rnm critical at silking and pollination stage.
- High altitude areas: Hybrids 611, 613 and 614C.
- Medium altitude areas: 511,512,622 and 632.
- Marginal rainfall areas: Katumani composite and Makueni composite.
- Coast regions: Coast composite and Katumani composite.
- Ploughing should be deep and done during the dry season to eradicate weeds.
- Require medium tilth.
- Plant spacing 75-90cm x 20-30cm.
- Planting done at the onset of the rains. This helps to reduce pest attack.
- Dry planting in areas with inadequate rainfall is necessary.
- Apply phosphatic fertilizer during planting at a rate of 120kg/ha P2O5
- Also nitrogenous fertilizers as top dress at the rate of 200kg of ASN or CAN.
- Control weeds by cultivation, use of appropriate herbicides, uprooting, slashing and mulching.
- Maize Stalk Borer:
- Nature of damage: Boring the leaves causing windowing effect, boring the stems and cobs.
- Control: Destruction of previous years crop residue, closed season and apply chemicals
- Maize Weevils:
- it is a storage pest.
- Damage: Bores holes into the maize grains, eating the contents.
- Control: Proper hygiene and sanitation in the stores.
- Use of chemicals such as Actellic Super.
- Symptoms: Red or brown pustules on the. leaves.
- Control: Plant resistant varieties and crop rotation.
- Cause: Fungus
- Symptoms: Black sooty mass of spores on maize heads or cobs(ear).
- Control: Crop rotation, growing resistant varieties and destruction of affected plant parts.
- Maize Streak Virus
- Cause: Virus
- Symptoms: Yellow longitudinal stripes parallel to the midrib.
- Control: Certified seed, early planting and rogueing.
- Harvest the crop 3-9 months after planting depending on variety.
- Maize stalks are cut and stocked in the field.
- Cobs removed by hand.
- For large scale harvesting, combined harvesters are used.
- Yields about 3,OOOkg and 4500kg/ha.
Areas where grown:
- Lower areas of Kirinyaga,
- Parts of Machakos
- Kerio Valley.
- Altitude: Does well in areas below 1200m.
- Rainfall: 500-600mrn per annum.
- Soils: Light sandy soils.
- Varieties: Serere 2A, 3A, 6A, 17, 16/9
Seed Bed Preparations
- Ploughing of land during the dry season.
- Soil should be of fine tilth since the seeds are small.
- Done at the onset of the rains.
- Planted by broadcasting and row planting at a spacing of 60cm x 15cm.
- Weeding is done until tillering.
- Top-dressing is done by use of sulphate of ammonia.
- Nature of Damage: Eats the seeds at milky stage.
- Control: Bird scaring devices.
- Cause: Fungus.
- Symptoms: Heads become sticky.
- Control: Use of certified seeds, crop rotation and destruction of affected crops.
- Cause: Fungus.
- Symptoms: Long, whitish lines on the leaves.
- Control: Crop rotation and field hygiene.
- Done by cutting off the heads.
- Drying of the heads.
- Threshing and winnowing of the grains.
- Stored under well ventilated dry conditions.
- Yields about 1000kg/ha with good management.
- Areas where grown: Western Kenya and Uganda.
- Altitude: 0-2400m above sea level.
- Rainfall: 900mm, drought resistant in the early stages.
- Soils: Free draining fertile soils.
- Serere varieties developed at Serere in Uganda.
- Ultra lupin
- 5.18 oats.
- The seedbed should be thoroughly prepared to a fine tilth due to the small size of the seeds.
- It also helps to control weeds.
- Finger millet should be planted as early as possible in the season.
- It is usually broadcasted by hand.
- If planted in rows, the furrows should be 30-33cm apart and the plants should be thinned to 5cm apart within the rows.
- Sulphate of ammonia at the rate of 125kg/ha is recommended for topdressing finger millet.
- Clean seedbed preparation
- Birds are controlled through scaring.
- Cause: Fungus
- Symptoms: Brown spots with grey centres on the leaves and stems below the inflorescence.
- Control: Use of resistant varieties.
- Individual heads are cut with knives.
- Heads are dried, threshed and winnowed.
- Yields 1650kg/ha with good management.
- It is grown in Western, northern, Rift Valley, Eastern and some parts of Central Province.
- Altitude: 0-1500m above sea level.
- Rainfall: 420-630mm. It is drought resistant.
- Soils: Fairly fertile and well drained soils.
- Dobbs variety.
- Serena variety.
- Broadcasting the seeds on the firmly prepared seedbed.
- Intercropped with other crops especially maize and beans.
- Can be planted in pure stands at a spacing of 60cm x 15cm
- Responds well to farmyard manure (FYM).
- Inorganic fertilizers are not commonly used in growing sorghum.
- Bird pests: They are the most common sorghum pests.
- They include
- aethiopica (Sudan Dioch),
- weaver birds,
- starling bird
- bishop’s bird.
- They are controlled through;
- killing them using explosives,
- poison spraying in their breeding places
- use of flame throwers.
- Sorghum shoot-fly controlled by early planting, closed season and application of insecticides.
- Stem borer – control by use of insecticides and field hygiene.
Common sorghum diseases include:
- Leaf blight
- Sooty stripe.
- Loose smut
- Head smut
Smuts are controlled by seed dressing-while the other diseases are controlled by growing resistant varieties.
- Sorghum is ready for harvesting 3-4 months after planting.
- Heads are cut off using a sharp knife after which they are sun-dried, threshed, winnowed and stored.
- Up to 3000kg/hectare can be obtained with good management.
- Grown in all provinces where maize is grown.
- Altitude: 10.00-2100 metres above sea level.
- Rainfall: Average of 62Smm per annum.
- Soils: Well drained loamy soils rich in organic matter.
Varieties for dry beans:
- Rose Coco,
- Mwezi Moja,
- Canadian Wonder,
Variety for canning: Mexican 142.
Varieties for French Beans:
- Long Tom,
- Master Piece
- Land should be prepared early.
- Primary and secondary cultivation done to control perennial weeds.
Seed Selection and Treatment
- Select wholesome seeds free from damage and wrinkles.
- Seeds are dressed against bean fly.
- Seeds should be inoculated with appropriate bacteria (none dressed seeds)
- Planted at the onset of the rains.
- Spacing 30-45cm x 15cm.
- Apply phosphatic fertilizer during planting time.
- Plant 2-4 seeds per hole.
- Provide sticks for the climbing varieties.
- Control of weeds through shallow cultivation.
- Top-dress with nitrogenous fertilizer for example CAN.
- Nature of damage: Feeds on the stems causing swelling at the roots.
- This results in wilting and death.
- Control: Dressing of seeds, early planting and spraying with insecticides.
- Bean Bruchid (Storage Pest)
- Nature of damage: Make dark circular windows on the grains.
- Control: Clean stores, fumigation, and seed dressing.
- Bean Anthracnose
- Cause’ Fungus
- Symptoms: Brown or black lesions on the underside of the leaves, pods and stems.
- Control: Growing resistant varieties, crop rotation, destruction of crop residues and spraying with fungicides.
- Bean Rust
- Cause: Fungus
- Symptoms: Red brown pustules on the leaves.
- Control: Planting resistant varieties and spraying copper fungicides.
- Done during the dry season for dry beans and when the pods are dry.
- Threshing and winnowing done.
- Sorting of rotten, off types and damaged ones.
- Sold to National Cereals and Produce Board when dry.
- For French beans, pick the pods when soft and green.
- Market immediately to avoid shrivelling.
Areas where grown;
- Mwea Tabere Irrigation Scheme
- Ahero Pilot Scheme in Kano plains.
- Bunyala in Busia.
- Bura in Tana River.
- Plots of 0.4 hectare are made with bunds constructed around them.
- Plots are flooded for four days.
- Rotavators/jembes are used to work the flooded fields on the fifth day.
- The land is then levelled and allowed to drain.
- During land preparation, water level should be about 7.5-10cm.
- During levelling water level should be 5cm
- Water is drained off completely for direct sowing.
- For transplanted rice, water level should be 5cm at transplanting.
- Water level should be maintained at 1/3 the height of plant until maturity.
- Water should be allowed to flow slowly through the fields.
- Old water should be changed every 2- 3 weeks if the flow of water is not possible.
- Water introduced should always be warm to ensure pollination.
- S.A applied in the nursery.
- Rate of 25kg SA for every nursery unit of 18.5m x 18.5m.
- Phosphatic fertilizers broadcasted in the field.
- Rate of 120kg ha DSP before planting.
- S.A applied in the field in two splits before and after transplanting at a rate of 250kg/ha
Flooding in Rice
Flood water in rice production is important for the following reasons;
- It provides good conditions for growth such as high humidity.
- Kills soil organisms.
- Prevents denitrification.
- Controlled through flooding.
- Appropriate herbicides such as propanil and butachlor are also used.
Harvesting of Industrial Crops
- cotton, pyrethrum, sugarcane, coffee and tea.
Harvesting of Cotton
Stage of harvesting
- Takes 4 months to mature.
- Harvest when bolls are dry and fully opened.
Method and Procedure
- In Kenya cotton is picked manually.
- Sort out grade AR (safi) from grade BR
- (fifi) into separate containers.
- Harvest during dry conditions to prevent dirtifying the lint.
- Avoid use of gunny bags to prevent contamination.
- Avoid picking leaves.
- Harvest on weekly basis.
Harvesting of Pyrethrum
Stage of harvesting
- Takes 3-4 months to mature.
- Harvest the flowers with disc florets which have assumed a horizontal position.
Methods and Procedure
- Pyrethrum is picked manually.
- Flowers are picked by twisting the heads so that no stem is attached.
- Clean harvesting should be done.
- Avoid picking leaves.
- Flowers are placed in woven baskets.
- Overblown flowers are picked and thrown off.
- Pick the flowers when the dew is dry.
- Harvested flowers should be taken to the factory the same day.
- Avoid compaction of flowers in the basket.
- Harvesting interval, once in two weeks during the wet season and once in a month during the dry season.
Stage of harvesting;
- Take 14-20 months for the plant crop to mature and 12-16 months for the ratoon crop.
- Sampling of cane is done before harvesting to ascertain the correct sugar content.
Methods and Procedures
- Cut the cane at the ground level to avoid yield loss.
- The green tops are removed from the canes.
- Harvesting matchet is used for cutting the cane.
- Cane should be harvested immediately at maturity to avoid lowering quality.
- The green tops should be removed immediately after cutting to avoid reduction of sugar content by enzyme invertase.
- Burnt cane should be harvested immediately after burning to prevent rapid inversion to monosaccharides.
- The cane should be processed within 48 hours.
Harvesting of Coffee
Stage of harvesting;
- Takes 2-4 years depending on the pruning system.
- Harvest only ripe berries.
Methods and Procedures;
- Hand picking is done so that ripe berries can be selected.
- During picking hooked sticks can be used to bend the tall trees.
- Only the uniformly ripe berries should be picked.
- Over-ripe and under-ripe berries should be dried and sold as buni.
- Ripe cherries should be processed on the same day they are picked.
Stage of harvesting
- It takes 2-4 years for tea to mature depending on the method of bringing young tea into bearing.
Method and Procedures
- Tea harvesting is known as plucking.
- Fine plucking – 2 leaves and a bud are removed.
- Coarse plucking – 3 leaves and a bud are removed.
- A straight fitto(straight stick) is used to guide the plucker on the plucking table.
- Tipping is done by cutting off shoots that appear above the fitto.
- Plucked tea is placed in woven (well ventilated) baskets to prevent fermenting before it reaches the factory.
- The plucked tea should be kept in a cool place awaiting transport.
- It should be processed within the same day of harvesting.
- Harvesting is done on a weekly basis under wet conditions and once after every two weeks under dry conditions.
- These are plants which either grow naturally or are cultivated by man to be used for feeding livestock.
- The term forage crops include pasture and fodder crops.
- Fodder crops are purposely grown for feeding livestock.
- They are cut or uprooted when ready
- Pasture is a ground cover of grass or a mixture of grass and legumes grazed directly or cut and fed to livestock.
Classification of Pastures
- According to type of stand.
- Either pure
- Mixed stands.
- According to ecological zones .
- Low altitude,
- Medium altitude,
- High altitude pastures
- According to the establishment .
- Artificial pastures.
Examples of grasses
- Congo signal,
Examples of legumes;
- This involves clearing the land, primary and secondary cultivation to a fine tilth because the seeds are small.
- This is done during the dry season.
Selection of planting materials
- Select seeds of high germination percentage,
- Free from impurities or buy certified seeds.
- If vegetative materials are used, select from high yielding, vigorous-growing and healthy plants.
Treatment of legume seeds
- Legume seeds are inoculated with the correct strain of bacteria which fix nitrogen for the crop.
- This is done at the beginning of the rains
Methods of sowing are;
- Direct sowing,
- Under sowing,
This is introduction of a pasture legume in an existing grass pasture.
The establishment of a pasture in an already existing crop which acts as a cover crop.
Seeds rate depend;
- On purity of seeds,
- Pasture species
- Whether pure or mixed stand.
Apply phosphatic fertilizer when planting and later top-dress with nitrogenous fertilizer.
- Re-seeding or gapping; Re-seeding is done if the grass is completely denudated.
- But if partially, gapping can be done
- Control of weeds by slashing, uprooting and mowing
- Fertilization of pastures-done by use of manures and nitrogenous fertilizer.
- Topping;This is the removal of stemmy fibrous material left behind after grazing.It allows new growth after the rains
- Control of pests-done by trapping of moles, use of pesticides and biological means.
- Pastures should be utilized at maturity when nutritive value is high.
It is utilized through the following methods:
- Direct grazing – this can be done through rotational grazing or herding.
- Zero grazing – this is where the pasture is cut and fed to the animals in the stalls.
Common fodder Crops
- Altitude: 1500 – 2000m above sea level.
- Establishment: Young tubers or bulbs are used.
- Spacing: 1m x 1m.
- Management: Does well with application of farmyard manure and requires fertile land.
- Utilization: Tops and tubers are sliced and fed to livestock.
- Conservation: Bulbs or tubers are sliced and stored.
- Altitude: 0 – 2000m above sea level.
- Establishment: Stem cuttings or splits.
- Spacing: 1 m x 50cm.
- Apply phosphatic fertilizers during planting time.
- Top-dress with nitrogenous fertilizers in split application.
- Clean weeding when young.
- Cut when 6-8 weeks or 1m-1.5m in height.
- Utilization: Cut stem is fed to livestock.
- Conservation: Ensiled when in plenty.
Types of Napier Grass:
- Bana grass (broad-leaved with hairy leaves)
- Clone (thin-stemmed and hairless)
- French Cameroon (thin-stemmed and not hairy).
- Pakistan hybrid (thin-leaved with hairy leaves).
- Used for silage making.
- Altitude: 1500 – 2500m above sea level.
- Soil: Deep red soil are ideal.
- Establishment: Inoculated seeds are planted 30-50cm apart in the rows.
- Management: Weeding and fertilizer application.
- Utilization: Cut wilted and fed to livestock before flowering stage.
- Conservation: Hay, silage, dried materials such as cubes or pencils.
- Is a root crop.
- Root is utilized as livestock feed.
- Ripe ones are used.
- Leaves used as livestock feeds.
- Leaves and stems used as livestock feed.
- Columbus grass
- Sudan gras
- Established from seeds which are drilled or broadcasted.
- Columbus grass should be dried before feeding to animals to avoid hydrocyanic and prussic acid poisoning.
Desmodium (Desmodium spp)
Two varieties ;
- Green leaf
- Silver leaf.
- Established from seeds on thoroughly prepared clean beds.
- Can also be inter-planted with Napier grass.
- Cut and wilted before feeding to livestock.
Agroforestry, trees used as fodder crops include:
Forage can be conserved as;
- Standing forage.
Importance of forage conservation:
- To reserve excess forage for use during time of shortag
- To avoid unnecessary wastage of f
- Conserved forage can be sold.
- To have sustained supply of feed for livestock throughout the year.
- This is the dehydration of green pastures to a moisture content of 16-20 per cent:
Steps in hay making:
- Cut the crop when the sun is shining.
- Dry the materials for 1-2 days.
- Windrow the dry material to allow for further drying.
- Bale the dry materials for storage.
- Store under shed or shelter.
Factors Determining Quality of Hay
- Stage of growth at which forage is harvested.
- Leaf content of the forage material.
- Method of handling and curing the hay.
- Form in which material is fed to livestock.
- Species of forage used.
- Amount of foreign materials in forage.
- This is a feed produced by conserving forage in succulent form through the process of fermentation by anaerobic bacteria.
Steps in silage making:
- Cut the crop and transport it to the silo,
- Material with a high moisture content is wilted in the sun for 4-48 hours before ensiling .
- Material is chopped to reasonable size pieces before filling in the silo.
- Spread the chopped material evenly.
- Check temperature if below 31°C, needs further filling; if above 31 °C compaction is necessary.
- Filling should be complete by the end of the third or fourth day.
- The silo is covered with 15cm of straw, sawdust then 15cm of soil to make it air and water tight.
- A trench is dug round the silo to keep off surface water.
Factors Affecting the Quality of Silage
- Maturity stage of the crop when cut.
- Type of crop.
- Moisture content of the material
- Additives such as molasses.
- Degree of compaction.
- Size of pieces ensiled.
- Amount of foreign materials included in the silage.
- Amount of leaf of the ensiled material.
- This is forage left in the field to be used during the dry season.
Livestock Health III: (Diseases)
Livestock diseases are classified according to causative agents as follows:
- Protozoan diseases -caused by protozoans.
- Bacterial diseases – caused by bacteria:
- VIral diseases – cause by virus.
- Nutritional diseases – brought about by nutritional disorders.
- East coast Fever (ECF).
- Anaplasmosis (gall sickness)
- Trypanosomiasis (Nagana)
East coast Fever
- Animals attacked: Cattle
- Cause: Protozoan. (Theileria parva)
- It is a tick-borne disease transmitted by red-legged tick and brown ear tick.
- Rise in body temperature.
- Swelling of lymph glands below the ear.
- Difficulties in breathing.
Control and Prevention
- Control of vectors through dipping and fencing.
- Treatment by use of clexon in the early stages.
Anaplasmosis (gall sickness)
- Cattle between 2 months and 2 years.
- Lambs and kids.
Cause: Protozoan (Anaplasma marginale)
- Transmitted by the blue tick
- contaminated surgical instruments and hypodermic needles.
- Fever/rise in body temperature.
- Constipation or hard dung.
- Paleness in the gums, eyes and lips.
- Drop in milk production.
- Tick control.
- Intramuscular injection of antibiotics and iron giving injections.
Coccidiosis of Poultry
- Cause: Protozoan (Eimeria spp.)
- Sudden death of chicks.
- Whitish, yellow and blood stained diarrhoea.
- Ruffled feathers.
- Chicks become paralysed before dying.
- Chicks become anaemic and dull.
- Disinfection of chick house.
- Prevention of contamination of food and water with droppi
- Use of prophylatic drugs for example, Coccidiostats.
- Animals attacked: cattle, sheep and goats.
- Cause: Protozoan of the trypanosome species,
- Vector-tsetse flies.
- Anorexia/loss of appetite.
- Loss of body condition/emaciation.
- Swollen lymph nodes.
- Lachrimation which leads to blindness.
- Rough coat and sometimes without hair and may be cracked.
- Swelling in parts of the belly.
- Drop in milk production in lactating cows.
- Loss of hair at tail end.
- Abortion may occur in pregnant females.
- Treating animals with trypanocidal drugs.
- Effective vector (Tsetse flies)control
- Confinement of wild animals in game parks.
- Fowl typhoid
- Foot rot.
- Contagious abortion.
- Animals attacked: All domestic birds which include chicken, turkey and ducks.
- Causes: Bacteria (Salmonella gallinarum}
- Depression/appearing very sick.
- Respiratory distress.
- Drooping wings.
- Sleepy eyes.
- Anaemia resulting in pale and shrunken
- combs and wattles.
- Greenish yellow diarrhoea.
- Killing all affected birds and proper disposal of the carcasses.
- Maintaining hygiene in the poultry house.
- Ensuring that the house is dry and well ventilated.
- Obtaining chicks from reliable sources.
- Treatment using sulphur drugs which are mixed in drinking water or mash.
- For example: application of Furazolidone (Furazol) at the rate of 0.04% in mash for 10 continuous days treats the disease effectively.
- It is also referred to as foul-in-the foot.
- Animals attacked: cattle, sheep and goats.
- However, it is most serious in sheep.
- Cause: Bacteria (Fusiformis necrophorus and Fusiformis nodosus).
- Animal’s foot becomes swollen.
- Lameness is observed.
- Pus and rotten smell come out of the hoof.
- Sheep are found kneeling while grazing when the front feet are affected.
- Animals spend most of their time lying down when the hind feet are affected.
- Emaciation due to lack of feeding.
- Hygiene in the living places.
- Regular foot examination and hoof trimming.
- Use of a foot bath of copper sulphate solution at 5-10% solution or formalin at 2-5% solution.
- Treating wounds on the feet with antiseptics.
- Affected animals should be given antibiotic injections.
- Isolation of sick animals from healthy ones.
- Avoid dampness and muddy conditions.
Contagious Abortion (Brucellosis/ Bang‘s Disease)
- Animals attacked: cattle, sheep, goats and pigs.
- It also affects ma
- Cause: Bacteria
- Brucella abortus in cattle,
- Brucella suis in pigs
- Brucella malitensis in goats and sheep.
- Spontaneous abortion or premature birth.
- Retained placenta if abortion occurs during the later stages of pregnancy.
- Infertility in cows while bulls have low libido and inflamed testis also known as orchitis.
- A yellowish brown, slimy, odourless discharge from the vulva may occur after the abortion.
- Use of artificial insemination.
- Slaughtering affected animals followed by proper disposal of their carcasses.
- The attendant to the animals should avoid contact with the aborted foetus.
- A blood test should be carried out for all breeding animals to detect the infected ones.
- Hygiene in the animals’ houses.
Scours (white Scours)
- Animals atacked: calves, piglets, lambs and kids.
- Cause: A bacterium which attacks young animals in the first week of life.
- White or yellowish diarrhoea.
- Pungent smelling faeces.
- Anorexia/loss of appetite.
- Sunken eyes.
- Undigested milk and mucus with blood spots observed in the faeces.
- Faecal matter sticks to the hind quarters.
- Sudden death if no treatment is given.
- Maintaining hygiene in the young animal housing units.
- Avoiding dampness on the floor of the house.
- Fingers of the attendant training calves to drink milk from a bucket must be disinfected.
- Calving should be carried out in a clean area.
- Have separate attendants for the infected calves to prevent disease spread.
- Replacing milk with warm water mixture.
- Treating affected animals with antibiotics.
- It is also known as black leg.
- Animals attacked: All ruminants aged between 8 – 18 months.
- Cause: Bacteria (Clostridium chauvei and Chauvei septicum)
- Fast and heavy breathing.
- Cracking on the swollen parts if touched.
- Swelling of the affected parts usually the hindquarters, shoulders and chest or back.
- Grunting and grinding of teeth.
- Animal stops chewing cud.
- Treating with recommended antibiotics.
- Vaccinating using black quarter vaccine known as blanthax.
- Burying the carcass deep or burning it completely.
- Is an inflammation of the udder.
- Animals attacked: Goats, cows, pigs and human beings.
- Cause: Bacteria (Streptococcus spp. or Staphylococcus spp.)
- Incomplete milking.
- Injuries on the udder and teats.
- Weak sphincter muscles of the teats allowing free flow of milk.
- Milk is watery, blood stained or clotted.
- Swollen udder
- Proper milking techniques.
- Treatment by use of antibiotics.
- Culling of animals which are often attacked.
- Attacks all domestic animals.
- Cause: Bacteria (Bacillus anthracis)
- Sudden death.
- High fever.
- Grinding of the teeth.
- It is an inflammation of the lungs.
- Animals attacked: Calves, kids, lambs, piglets and poultry.
- Bacteria (Mycoplasma mycoides)
- worms in the lungs.
- Anorexia/loss of appetite.
- Staring coat.
- Breathing rapidly.
- Abnormal lung sounds when breathing.
- Coughing if the chest is pressed.
- Fluctuating body temperature.
- Nasal discharge.
- Keeping young animals in warm pens.
- Proper sanitation.
- Isolation of the affected animals.
- Treating using antibiotics.
- Foot and mouth disease (FMD).
- New Castle
- Fowl pox
- African swine fever
- Animal attacked: Cattle and wild game.
- Cause: virus.
- Harsh staring coat.
- Rise in temperature.
- Eye discharge (Lachrimation)
- Diarrhoea and dysentery.
- Ulcers in the mouth.
Foot and Mouth Disease
- Animals attacked: Cattle, sheep, goats and pigs.
- Cause: Virus .
- Sharp rise in temperature.
- Blisters in the mouth, hooves, udder and teats.
- Loss of appetite.
- nursing wounds with disinfectant.
- Animals attacked: Poultry.
- Cause: Virus.
- Difficulties in breathing.
- Beaks remain wide open and necks are strained.
- Birds become dull.
- The birds stand with eyes closed all the time.
- Anorexia/loss of appetite.
- Nasal discharges which force the birds to shake their heads to clear it.
- Birds walk with a staggering motion.
- Paralysis of wings and legs may occur.
- Birds have their beaks and wings down.
- Birds produce watery greenish diarrhoea.
- Birds lay soft shelled eggs.
- Killing all birds and burning them followed by cleaning and disinfecting the houses before bringing in new stock.
- Vaccination should be done during the first 6 weeks and then 2-3 months later.
- Animals affected: Poultry.
- Cause: A virus known as avian fox.
Two types of fowl pox with different symptoms.
- Cutaneous type
- Diptheritic type
The cutaneous type affects the skin and has the following signs:
- Injuries on the combs and wattles, legs, vent and under the wings.
- Loss appetite.
The diptheritic type affects internal membranes and has the following symptoms:
- Injuries in the inside of the throat and mouth membranes resulting in difficult breathing and swallowing.
- Eyes and nose produces a watery liquid.
- Loss of appetite.
- Killing all affected birds followed by proper disposal of their carcasses.
- Vaccinating remaining healthy birds.
- It is also referred to as poultry AIDS.
- Animals attacked: Poultry.
- Cause: A virus known as Birma virus.
- The glands above the vent (bursa) become swollen.
- Drop in egg production.
- Birds develop respiratory distress.
- Loss of appetite.
- Low water intake by birds.
- Loss of immunity making the birds more susceptible to opportunistic diseases.
- Administering vitamins and especially
African Swine Fever
- Animals attacked: All domesticated pigs.
- Cause: A virus known as Irido virus.
- Loss of appetite.
- Nasal discharge.
- Diarrhoea in serious conditions.
- Killing all affected animals and proper disposal of their carcasses.
- Double fencing to keep wild animals away.
- It is a non-infectious disease brought about by calcium deficiency in animals which have recently given birth.
- Animals attacked: Cows, goats and pigs that have recently given birth.
- Due to low calcium levels in the blood.
- Which leads to an increase in the magnesium and sugar level in the blood.
- Mostly occurs in high producing cows in the first few months of lactation.
- This is because these animals loose more calcium through milk secretion than they are getting from the diet.
- Muscular twitching causing the animal to tremble.
- Staggering as the animals move.
- Animal falls down ands becomes unconscious.
- The animal lies down on its side and the whole body stiffens.
- Body functions such as urination, defecation and milk secretion stops.
- Stomach contents are drawn into the mouth which later cause lung fever when breathing in.
- Loss of appetite.
- Intravenous injection of soluble calcium salt in form of calcium boro-gluconate ,60gms dissolved in 500cc of water.
- Keeping the animal in a comfortable position on its sternum.
- Giving fresh water.
Note: The animals suffering from milk fever should not be given medicine orally for the following reasons:
- It will not be able to swallow medicine.
- The medicine may get into the lungs thereby promoting lung fever.
- Partial milking for the first 10 days.
- High yielding cows should be given rations containing phosphorus and calcium.
- Giving high doses of Vitamin D.
- Animals attacked: Cattle and sheep.
- Cause: Accumulation of gases as a result of fermentation in the rumen.
- The left side is blown up.
- Sudden death.
- Relieve by use of trocar and cannula.
- Chasing the animal around if noticed early.
- Drenching by use of stop bloat.
- Feeding ruminants with dry roughages during the wet season before grazing on lush pastures.
Livestock Production V (Poultry)
- Poultry industry in Kenya has developed tremendously due to the use of artificial incubation and brooding and easy availability of hybrid birds, both eggers and broilers.
- Poultry production has become an easy source of income and food for the rural as well as the urban communities.
- The term poultry includes domestic birds such as turkeys, ducks, geese, pheasants, doves and pigeons.
- Of late ostrich farming has become a lucrative activity.
- Poultry production starts with incubation of eggs.
Parts of an Egg
- Forms 10-12% of the whole egg content.
- Made of calcium and phosphorus.
- Protects the inner egg contents.
- Shell membrane
- Made of inner and outer membranes.
- Lining of the egg shell.
- Constitutes 1 % of the total egg content.
- Albumen (egg white)
- About 55-60% of the total egg content.
- It is divided into chalaza, thick and thin albumen.
- Chalaza holds the egg yolk in position.
- Albumen serves as food for the chick.
- 30-33% of the total egg content.
- Supply embryo with nutrient
- Germinal disc -The embryo which develops into a chick if fertilized.
- Vitelline membrane – Gives the yolk its round shape.
- Air sac
- Keeps the egg fresh by allowing gaseous exchange.
- Provides oxygen for the embryo
- This is the practice of determining the internal qualities of an egg by examining it against a light source.
- The egg is placed on a hole made on a .cardboard box.
- This is called a candling box.
- A source of light is placed in the box directly under the egg.
- The observer then looks through the egg against the source of light below.
- Abnormalities on and within the egg can be seen through the translucent shell.
- Involves the provision of fertile eggs with the proper condition for embryonic development.
Selection of Eggs for Incubation
- Should be fertile.
- Should be of medium size about 55- 60gms in weight.
- Should have smooth shell.
- Should be oval shaped.
- Should not be cracked.
- Eggs should be clean to ensure that pores are open.
- Should not have abnormalities such as blood spots, meat spots and double yolk. .
- Eggs should not be more than 5 days old.
- Eggs should be fresh that is collected within one week.
Internal egg qualities can be determined through the egg candling process.
Methods of Incubation
- This involves the use of a broody hen which sits on the eggs to provide them with conditions necessary for hatching.
- Takes 20-21 days.
- The hen is given about 10-15 eggs.
Signs‘ of Broodiness in Poultry
- Tendency to sit on an egg after laying.
- Moulting of the hen.
- Making some noise at the laying nests.
- Feathers are raised.
- It becomes aggressive when disturbed.
- It stops laying.
Preparation and Management of Natural Incubation
- The hen is given “China eggs” to sit on to induce broodiness.
- When broody the hen should be provided with a nesting nest or a saucershaped nest scooped on the ground.
- The nest shall be lined with soft bedding and fertile eggs provided.
- The eggs are set in the evening or night.
- The bird is dusted to control external parasites.
- The hen is allowed t hour outside to feed and exercise everyday.
- Broken eggs should be removed immediately.
- The hen should not be disturbed.
Advantages of Natural Incubation
- It is cheap.
- High hatchability.
- Low risk involved.
- Useful in small scale production.
- Less skill is required.
- Less laborious.
Disadvantages of Natural Incubation
- Egg production is low because the hen will not lay eggs during incubation.
- It is not possible to plan when to incubate.
- If the hen dies the eggs will be destroyed.
- If the hen deserts the eggs or refuses to sit on them the farmer will incur losses.
- Only few chicks can be hatched at a time by one hen.
- Diseases and parasites could easily be transmitted to the chicks.
- This is the use of artificial device known as an incubator for hatching eggs.
Conditions Necessary for Artificial Hatching of Eggs
- Temperature – maintain at 37.5°C-39.4 °C throughout to control the rate of embryonic development of the chick. High or low temperatures are lethal.
- Ventilation – Good air circulation.
- Carbon dioxide: oxygen ratio maintained at 0.03%:21 %.
- Relative humidity – Maintained at 60%.
- High humidity leads to marshy chicks
- low humidity the chick may stick to the shell.
- Turning of Eggs –
- Done 3-4 times a day to facilitate uniform distribution of heat for uniform development of chick.
- Turn slowly 180 ° clockwise along the axis to avoid breaking the blood v
- Some incubators have automatic turning mechanism.
- Cleanliness – cleaning and disinfecting the incubator with formaldehyde solution.
Advantages of Artificial Incubation
- It facilitates large scale production of chicks.
- Incubators are always ready when needed.
- Artificial incubation leads to higher egg production because broodiness in the hens is not required, so there is more time for laying eggs.
Disadvantages of Artificial Incubation
- High initial capital in buying an incubator.
- High level of management and attention is required.
- It is not economical for only a small number of eggs.
- High risks involved in turning the eggs.
Brooding and Rearing of Chicks
- Brooding is the rearing of day old chicks upto 8 weeks old for the layer chicks and 2 weeks for the broiler chicks.
- For successful brooding the source of the chicks should be considered.
Sources of Chicks
The following factors should be considered:
- The reputation of the supplier (hatchery).
- Time taken by the chicks in transit.
- Proper sexing and breed identification.
- A hen is allowed to take care of the chicks.
- She provides them with warmth and security.
- She stays with the chicks for 8 weeks and then rejects them.
- It is cheap.
- Less labour is needed.
- Suitable for small scale.
Disadvantages of Natural Brooding
- Not possible to produce large numbers of chicks.
- The hen goes off laying during brooding time.
- Only possible when a broody hen is available.
- The chicks are raised artificially in a structure known as a brooder until they are 8 weeks old.
- Temperature – should be about 35°C in the 15th week and reduced to 21°C by the 8th week.
- Litter – wood shavings which are capable of absorbing 60% moisture without showing wetness should be used.
- Space confinement – Done by use of hardboards which are about 25cm high and form a circular space. A space of 1m2 for 25 chicks is required.
- Feeders and waterers – should be enough for the chicks and evenly distributed in the brooder.
- Ventilators – windows should be enough to allow proper air circulation but direct draught should be avoided.
Types of Heaters in the Brooder
- Electric heaters – one ordinary bulb 100 watts can raise 30 chicks.
- One infrared bulb 240 watts can raise 100 chicks.
- Kerosene burners – Hurricane lamps can raise 100 chicks.
- Charcoal burners – these are specially made jikos with heat deflectors.
Preparation Before Chicks Arrive
- Start 2-3 days before arrival.
- The brooder house should be cleaned to remove old litter and then disinfected.
- New litters 5-1Ocm high should be put in and covered with absorbent materials/news papers.
- Equipment should be cleaned, disinfected and tested to make sure that they are working.
- The brooder is lit about 6 hours before the chicks arrive.
- Feed and water should be placed into shallow containers.
- Brooder space should be confined with a hard board to prevent chicks straying far from the source of heat.
Management After Arrival of the Chicks
- Chicks are placed in the brooder during the day to familiarize with the brooder.
- If chicks arrive stressed and weak they should be given glucose solution in the waterers.
- In case the heat source is charcoal burners they should be covered with wire mesh.
- Feed chicks with chick mash which is later mixed with growers mash as the chicks grow.
- Clean water should be provided and changed regularly.
- Constant attention should be given to the chicks for the first 2 weeks.
- Any vices should be checked and controlled.
- Any dead chicks should be removed as soon as seen.
- Ventilation should be used to control the temperature and humidity in the brooder.
- Constant disinfection is required at the entrance to avoid diseases.
- Brooder space should be increased as the chicks grow.
- Debeaking should be done at 10 days old.
- Vaccination against diseases such as Gumboro after 2 weeks, New Castle at 3-4 weeks and fowl typhoid at 7 weeks.
- Dusting to control external parasites.
- Growers’ mash should be introduced gradually at 7 weeks old.
- Chicks are removed from the brooder when they are 8 weeks old.
- On average the chick uses about 1.5kg – 2.2kg of chick mash by the time it is 8 weeks old.
Temperature Control in the Brooder
If the brooder temperatures are low the following should be done:
- Brooder space is reduced.
- Heaters are increased.
- Ventilators are closed.
If the brooder temperatures are too high the following should be done:
- Brooder space is increased.
- Heaters should be reduced.
- Ventilators should be opened.
Management of the Growers
- The growers are birds at the age of 9 weeks to the point of lay that is at 18 weeks.
- Growers should be fed on growers’
- By this time the growers should be occupying the main poultry house.
- Sick birds should be isolated and treated.
- A foot bath for constant disinfection should be placed at the entrance.
- Each bird is fed 115 gms per day of growers’ mash.
- Greens and soluble grit should also be provided.
- Clean water should be provided all the time (adilibitum).
- Drenching against internal parasites should be done by adding a dewormer into the water.
- Vermins should be controlled.
- Litter should be kept dry by turning.
- Vaccination should be done as required.
- Layer pullets require dimly lit house.
Management of the Layers
- Layers’ mash should be introduced at 18 weeks and increased gradually.
- The birds start laying at 18-21 weeks.
- The birds should be vaccinated against New Castle and fowl typhoid.
- Enough floor space roosts, feeders and waterers should be provided.
- Each hen should be given 120gms per day of layers’ mash.
- Clean water should be provided adlibitum.
- Eggs should be collected twice a day at noon and in the evening.
- Green leaves should be provided to keep the birds busy thus preventing cannibalism and improve the yellow colour of the yolk.
- Grains should be given in addition to the layers’ mash at the rate of 65gms per bird per day.
- Soluble grit or oyster shells should be provided at all times for efficient digestion and strong shelled eggs.
- Layers should be fed according to their body weight and the rate of egg production for example a 70kg bag should feed 100 layers for 4-5 days.
- Enough laying nests should be provided at least 1 per 5 layers.
- The laying boxes should be dimly lit to reduce egg eating.
- Debeaking should be done when necessary.
- Broken eggs and dead birds should be disposed off properly.
- The non-layers and cannibals should be culled.
Management of Broilers
- Broilers are table birds kept for meat production.
- They have high growth rates or high feed conversion ratio.
- The objective is to produce a kilogram of quality poultry meat from less than two kg of broiler feed.
- The broiler chick requires special broiler feed from day old to 4 weeks of age.
- Broiler starters’ mash or crumbs should be fed.
- This contains coccidiostat, high level of protein, vitamins and trace elements for early growth.
- From 4 weeks to 8 weeks they are given broiler follow-on mash or pellets.
- This feed contains high level of metabolisable energy to ensure a good cover of subcutaneous fat in the finished broiler.
- From 8 weeks until slaughter finisher pellets should be given to increase the size.
- Adequate clean water should be provided at all times (adlibitum).
- High level of hygiene should be maintained to reduce mortality rate.
- Birds should be dusted with appropriate pesticides to control external parasites.
- Deworming should be done routinely.
- Vaccination against common diseases should be done.
- Dead birds should be disposed off properly.
- Broilers should be kept under deep litter system, the house should be well ventilated and well lit.
Poultry Rearing Systems
- semi intensive
- intensive systems.
The Extensive Systems
- Birds are set free throughout the day to fend for themselves.
- Birds are confined in night shelters for the night.
- There is no supplementation.
- Birds eat insects and green leaves therefore less feed is required.
- Cheap method.
- Cannibalism and egg eating are reduced since the birds are not crowded.
- Manure is evenly spread in the runs.
- Low labour requirement.
- Birds get plenty of exercises thus helping to keep in good health.
- No need to provide grit as birds pick it from the soil.
- More land is required if a farmer wants to rear many birds.
- Birds can be stolen or eaten by predators.
- Eggs get lost in the vegetation or stolen.
- Eggs get dirty.
- Difficult to determine layers from non-layers.
- Birds get easily infected with diseases and parasites of the area.
- Breeding programme is not easy to follow.
- Birds can destroy crops where perimeter fencing is not constructed.
- Low productivity per unit area.
- Birds are confined in small portable structures called folds.
- A fold measures 3.5m long, 1.5m wide and 1.5m height.
- 1/3 of the fold is roofed while the rest is enclosed with wire mesh.
- Birds get plenty of sunlight.
- Birds get fresh grass as the fold is moved to new grounds.
- Manure is evenly spread in the field.
- Less feed is used because birds eat grass.
- Reduces build up of parasites and diseases since the fold is moved often.
- Birds are protected from predators.
- Few birds are kept per fold.
- It is laborious since the folds are moved from one place to the other.
- Individual egg production record is difficult to keep.
- The fold does not last long because of
- high frequency of handling.
- The return per unit area of land is low.
Deep Litter System
- Birds are confined in a house throughout their life.
- The floor of the house is made up of litter which accumulates over time.
- Enough feeders, waterers and laying boxes are provided depending on the number of birds and space available.
- Movable roosts and perches made of timber frames should be provided in the house.
- Stress and vices should be watched closely and controlled.
- Eggs should be collected as frequently as possible to prevent dirt and egg eating.
- The house should be dimly lit.
- The floor space requirement should be 1m2 per 2-3 birds.
- High stocking rate per unit area of land.
- Low labour requirement.
- Fast accumulation of manure.
- There is control of feeding, egg production and movement of birds.
- Safety of the birds is guaranteed from predators.
- No loss of eggs.
- Useful method when rearing breeding stock.
- Regular cleaning of the house is not necessary since the litter absorbs the droppings.
- Easy collection of eggs.
- High incidence of cannibalism like egg eating, feather plucking and toe pecking.
- Pests and disease causing organisms accumulate in the litter.
- Individual records of the birds are not possible.
- May be difficult to find litter.
- Eggs become dirty if laid on the floor.
- Feeders and waterers may be contaminated by the litter.
- The system encourages broodiness in hens.
- High infestation of diseases if the management is below standard.
- If there is a disease outbreak, it can spread very quickly throughout the house due to the communal housing.
- High cost of building deep litter house.
Battery Cage System
- Birds are confined in cages which are placed in the poultry house.
- The cages are made of wire mesh
- Each cage contains 1-3 birds.
- Water and feed troughs together with eggs trays are fitted along the front side of the cages.
- The floor of the cages should be slanting to allow the eggs to roll out of the cages.
- Droppings from the cages fall from behind for easy cleaning.
- Records are easily kept therefore culling is easy.
- Birds do not become broody.
- More eggs are collected due to restricted movement of the hens and complete control of egg eating.
- Tender meat is obtained from the culls because the muscles have not been toughened much.
- Handling is easier than in the other systems and individual attention to hens is given.
- Stocking rate is very high.
- Vices are greatly reduced.
- Eggs are clean because hens do not step on them.
- The system can easily be mechanised.
- Birds do not contaminate the food and water.
- Sick birds can be detected easily and isolated for treatment.
- Wire floors prevent re-infestation of parasitic worms and coccidiosis.
- No bullying during feeding.
- Low labour requirement.
- Initial costs for cages, equipment and house are excessively high.
- Requires high level of management.
- Higher maintenance costs where automation is used.
- Birds may get fatigue due to lack of exercises thus lowering productivity.
- In case of disease outbreak, spreading is very fast.
- Birds develop bruises on combs, breasts and toes as they stick their necks out-to feed and walk in the cages.
- Not useful when rearing breeding stock and the rearing of broilers.
- Cannot be used for brooding young chicks.
Stress and Vices in Chicken
- Stress is a condition imposed on the birds making them disturbed and uncomfortable.
- Stress reduces production and brings about poor performance.
- Vices are habits developed by animals.
- These affect production and health of the birds.
- Usually they are bad habits.
Cause of Stress in Poultry
- Sudden changes in routine management.
- Presence of strangers in the poultry house.
- Presence of animals and vermins.
- Too much noise.
- Constant and poor handling.
- Sudden weather changes.
- Disturbance of the pecking order.
- Poor hygiene.
- Disease and pest attack.
- Lack of food and water.
Control of Stress
- Poultry house should be kept quiet and constructed away from noise.
- Poultry house should be insulated to maintain constant temperatures.
- Parasites and diseases should be controlled.
- Change in routine management should be gradual.
- Enough feed and water should be provided.
- Feather pecking.
- Cannibalism (toe and vent pecking).
- Egg eating.
Pecking and Cannibalism
- Situation where birds peck at each other resulting in death or injury.
- Feather and body growth rate IS reduce
- Loss of birds due to death may result from cannibalism.
- Culling rate is increased (economic loss).
- The appearance of the carcass is spoiled thereby reducing its market value.
Causes of Cannibalism
- Overcrowding in the house.
- High temperatures in the poultry house making the birds uncomfortable.
- Too bright light.
- External parasite infestation.
- Inadequate and incorrect feeding.
- Idleness of the birds.
- Greediness of the birds.
- Disturbances of the pecking order.
- Prolapses of the rectum which occurs once in a while.
- Bright light in the lying boxes.
- Ample spacing should be provided on the floor, feeders, waterers and laying boxes.
- Overheating should be avoided during brooding.
- The house should be dimly lit for the layers.
- Laying nests should be darkened and above the groun
- Dusting should be done to control external parasites.
- Provide enough balanced ration.
- Birds should be kept busy.
- New/strange birds should not be allowed in the house.
A vice influenced by the following:
- Presence of broken or soft shelled eggs.
- Idleness of the birds.
- Inadequate laying nests.
- Mineral deficiencies.
- Bright light in the laying nests.
- Greediness of the birds.
- Eggs should be collected regularly.
- Laying boxes raised above the ground.
- Laying boxes should be darkened.
- Birds should be given balanced ration.
- Debeaking should be done as need be.
- Birds should be kept busy with greens.
- Birds should be kept according to age groups.
- Injured birds should be isolated and treated.
Marketing of Poultry Products
- Poultry products include eggs and meat.
Marketing of Eggs
- Eggs are delicate and perishable foods and have the highest value when fresh.
The factors considered when sorting out and grading eggs for the market include:
- Size/weight of the egg – large eggs fetch high prices than small ones. The average weight should be about 57gms.
- Shape of the egg – The normal egg shape is oval, with a broad end and a narrow end.
- Cleanliness – Consumers prefer clean eggs.
- Colour of the shell – Brown eggs are popular with the consumers.
- Candling qualities – candling is done to determine freshness of the eggs and presence of any other egg abnormalities.
- Shell texture – should be smooth and without cracks.
- Broilers are slaughtered at the age of 1-2.5months old with a life weight of 1.5-2kgs.
- The birds are killed and dressed in a clean way before being wrapped in clean bags ready for sale.
- The meat is sold in hotels and restaurants.
- Whole birds can be sold live in local markets.
Livestock Production VI (Cattle)
- Cattle production is a widely distributed enterprise in Kenya.
- Most farming communities choose between the exotic and the’ local breeds or their crosses depending on the environmental conditions.
- Whereas the backbone of beef industry in Kenya is made up of the indigenous animals and their crosses, and based in the somewhat drier areas, the-dairy industry is mainly based on the exotic breeds and their crosses and common in the wetter regions of Kenya.
- Whatever production undertaken, the returns depend mostly on the management levels provided to these animals.
- A productive herd starts with good management of the young stock.
Raising of Young· Stock.
- The young one of cattle is known as a calf.
Feeding Dairy Calves
- Newborn calves should be given colostrums within the first 3-5 days of their life.
- Colostrum is important for the following reasons:
- It is highly digestible.
- It contains antibiotics.
- It is highly nutritious.
- It serves as a laxative.
- It is highly palatable.
- Calves can be fed using natural method (direct suckling) or artificially/bucket feeding.
- In this method, calves suckle the mother directly.
- The calf takes milk at body temperature.
- The milk is free from contaminants.
- Less problems of scouring.
- Underfeeding of the calf may result.
- Cows may not let down milk in case the calf dies.
- Difficult to keep accurate production records.
- The calf is trained to feed from the bucket immediately after birth.
The calf is trained as follows:
- Well measured milk is put in a clean bucket.
- Index finger is inserted into the mouth of the calf.
- The head of the calf is lowered slowly into the bucket until the calf starts to drink the milk.
- The finger is withdrawn slowly as the calf continues to drink from the bucket.
- The procedure is repeated until the calf gets used to the process.
- Easy to keep accurate production record/milk yields of the cow.
- Possible to regulate the amount of milk given to the calf
- The cow does not need the presence of the calf in order to let down milk
- Easy to maintain high hygiene standards.
- Calf may be given cold milk
- Equipment used and the stockman may be dirty leading to scours
Preparation of artificial colostrums
- A fresh egg whipped in 0.86 litres of warm water
- Litre of warm water
- One teaspoonful of cod liver oil
- One tablespoonful of castor oil
- Note; colostrums is fed to the calves three times a day for the first 4 days of life and thereafter twice a day.
Weaning of calves
- Calf is fed on whole milk up to the tenth week then it is weaned
- Calf is given milk equal to 10% of its body weight up to the 8th week
- After 8th week, milk is reduced gradually by 1 kg until weaning
- Calf is given early weaning concentrates and soft forage
Early Weaning Guide
|Age in weeks||Whole milk(kg/day)||Concentrates(kg/day)|
|1||Colostrums ad libitum||–|
- Calf is fed on whole milk up to the 3rd week, when milk is replaced gradually with skim milk.
- At the age of 3weeks the calf is introduced to calf pellets or pencils and green fodder.
- The calf is given plenty of clean water.
- The calf continues to be given additional skim milk up to the age of 14 weeks when maximum amount of milk is given.
- Skim milk is reduced from 14 weeks to 16 weeks when weaning is done.
Late weaning guide
|Age in weeks||Whole milk
|1||Colostrums ad libitum||–||–|
Rearing of replacement stock
- The replacement stock includes young heifers and bulls which have been selected for breeding to replace the old stock.
- Parasite control-Spraying against external parasites and deworming against internal parasites.
- Disease control-Calves are vaccinated routinely against diseases such as;
- Blackquater-at 4 months old.
- Anthrax and Blackquater at 6 months old
- Brucellosis – 3-8 months old (heifers).
- Castration – for male calves not selected for breeding.
- Identification – Suitable methods are used. It allows proper record keeping.
- Removal of Extra Teats ;
- These teats are known as supernumerary teats which make milking of the animal difficult.
- They are clipped off with teat clippers.
- Dehorning/Disbudding – The removal of horn buds using suitable methods.
Requirement of a Calf Pen;
- Should be clean and easy to clean.
- Be warm and dry.
- Have adequate space to allow exercise and feeding.
- Should be properly lit and allow sunlight for Vitamin D.
- Have proper drainage to avoid dampness.
- Draught free to prevent chilling.
- Be well ventilated to allow fresh air.
Types of Pens
These can be;
- Have a solid floor raised above the ground.
- The floor should be slanted for drainage.
- Constructed near the milking parlour.
- Have an open floor to allow grass into the pen.
- Easily moved from one place to another to avoid soiling.
- Kept outdoors in the pastures to allow the calf to nibble on pastures.
- Calves should be housed singly up to the age of 3 weeks, when they are put in group pens.
- This is to avoid them licking each other and swallowing hairs which form indigestible balls.
Milk and Milking
- Milk is the white lacteal substance secreted by the mammary glands of the female mammals.
Composition of Milk
- Protein – Casein and whey.
- Fat – Butter fat.
- Carbohydrates – Lactose
- Minerals – mainly calcium and phosphorus.
Factors Affecting Milk Composition
- Age of the animal.
- Conditions of the animal.
- Stage of lactation and pregnancy.
- Completeness of milking.
- Type of breed.
- Season of the year.
- Type of food eaten.
- Physiological conditions such as diseases.
Milk Secretion and Milk Let-down
- Milk is secreted by the mammary glands which is an accessory gland of the reproductive system.
- The mammary gland of a cow is known as an udder.
Structure of the Udder
The udder is composed of the following parts:
- Alveolus cells – synthesize and secrete milk.
- Lobule – a group of alveolus cells.
- Lobe – Several lobules grouped together and drained by lactiferous ducts.
- Gland cistern – space where milk collects from the lobes.
- Teat cistern – A space where milk collects before emission.
- Teat -An organ which drains each quarter of the udder.
- The process of milk secretion is known as lactogenesis.
- The digested food is taken to the udder via blood vessels.
- In the udder the nutrients are carried into the alveoli cells where metabolic reactions take place to build up these nutrients into milk.
- A hormone prolactine is secreted by pituitary gland which brings about lactogenesis.
- The milk secreted is then stored in the upper parts of the udder waiting to be released.
- The process of milk let-down occurs naturally when the animal is stimulated.
- Milk secreted moves from alveolar region through the ducts to the gland cistern.
- Oxytocin, a hormone secreted by the pituitary gland causes the contraction of the udder muscles forcing the milk down the teats.
- Oxytocin hormone lasts 7 -10 minutes in the blood stream hence fast milking is important to withdraw the milk.
- Milk is withdrawn from the teats by gently squeezing them.
Factors Influencing Milk Let-Down
- Presence of the calf.
- Presence of the milkman/milker.
- Rattling of the milk equipment.
- Site of the food/feeding the animal.
- Massaging or washing the udder.
- Sight of the milk parlour.
Factors Inhibiting Milk Let-Down
- Beating the animal/inflicting pain to the animal.
- Presence of strangers and animals for example dogs.
- Poor milking techniques.
- Absence of the calf (in case the cow is used to it).
Clean Milk Production
The following factors are essential for clean milk production:
- A healthy lactating cow.
- A healthy and clean milker.
- Clean and properly constructed milking parlour.
- Clean and disinfected milking equipment.
- Proper handling of the milk after milking.
- The animals are brought near the milking parlour 15-20 minutes before milking to get into the mood of being milked.
- Milking materials such as equipment, feeds, ropes, stools and salve are collected and placed near the milking parlour.
- The animals are allowed into the milking stall one by one as the milking proceeds as follows:
- The animal is restrained in the stall.
- Feed is weighed and placed into the feed trough.
- The udder is thoroughly washed, disinfected and dried with a clean cloth.
- A strip cup is used to test for mastitis on each quarter.
- Milking proceeds by squeezing the teats with the full hand. If machine milking the teat cups are placed on the teats.
- For hand milking start with the hindquarters and finish with the forequarters.
- Fast milking should take about 8 minutes then end with stripping the udder.
- The milk is weighed and recorded.
- The animal is then released.
Dry Cow Therapy
- This is the infusion of antibiotics into the teat canal of a cow that is preparing for drying off.
- It prevents bacterial infection which leads to mastitis.
- Pasteurized milk – milk that is heated and cooled immediately.
- Ultra Heat Treated (UHT) – milk heated to a temperature of 130-135C, packed and then cooled.
- Butter – Milk butter fat separated by a process known as churning.
- Cream -A layer of is: that collects at the top of the milk when left to stand.
- Cheese – Milk proteins which have been compressed.
- Ghee – Milk fat made from heating cream or butter.
- Skim milk – Milk without butter fat.
Marketing of Milk
- The Kenya Dairy Board regulates the production and sale of milk and milk products through various Dairy Co-operative Societies.
- Processors and distributors of milk and milk products include;
- Brookside Dairies,
- Delamere Dairies
- Limuru Dairies.
Marketing of Beef
Done by the following:
- Individual fanners through the local slaughter house.
- Livestock marketing division.
- Kenya Meat Commission.
- Farmer’s Choice.
Farm Power and Machinery
- Farm power is any form of energy used in the farm to do work. .
Sources of Farm Power
- Performs light tasks.
- Quality of work produced is variable.
- Takes a long time to complete a task.
- Done by draught animals such as camels, donkeys, horses and elephants.
- Used in land preparation and transportation.
- Animals are liable to sickness and get tired.
- Need enough food.
- To pump water from boreholes.
- To winnow crops such as beans, finger millet and rice.
- Generate electricity.
- Not easy to control and may not be available when needed.
- Grinding mills (to grind maize grains).
- Difficult to use in the farm because it is not easy to control.
- wood or charcoal
- biogas power.
Charcoal/Wood Fuel Energy
- Provides heat for boiling water and cooking.
- Dehydrating of some crops.
- Curing of tobacco.
- It cannot be used directly in some farm operations.
- Large quantities are required.
- They are bulky hence difficult to transport.
- Provides heat and light for cooking, boiling water and lighting.
- Produces electricity.
- Only possible where there are animals under zero grazing unit.
- It is labour-consuming.
- Large quantities of dung are required.
- Cannot be used directly in some farm operations.
- petroleum oils
- natural gas.
- Petrol or diesel is burned in internal combustion engines to produce power.
- Kerosene is the main source of power to light rural homes.
- Natural gas is used for cooking, heating and lighting.
- hydro-electrical power (HEP),
- power stored in batteries.
- Nuclear energy is a potential source of power which has not yet been used in the farms.
Uses of Electrical Power
- Runs stationary machines such as milling machines, grinding mills, cooling machines and water pumps.
- Supplies heat and light for operations of brooders.
- Cannot be used directly in some farm operations.
- Lack of electricity in the rural areas.
- Power failures can lead to high losses.
- It is costly to install and maintain.
Energy obtained from the sun.
- Provides heat and light.
- Used by all the plants in photosynthesis.
- Dehydrating crops such as vegetables, maize grains, beans and hay.
- Boils water which drives turbines to produce power for minor uses.
- Low concentration of energy on cloudy d
- Expensive In collecting and concentrating equipment.
- Cannot be used directly in some farm operation
- Requires skilled labour to install and maintain.
- The tractor has an internal combustion engine which burns petrol or diesel to produce power.
- This power is then passed to the gear box from where it is transmitted in various ways.
- The common tractor engine is a four stroke cycle engine.
The four strokes are:
- Induction stroke.
- Compression stroke.
- Power stroke.
- Exhaust stroke.
- Piston moves down.
- Inlet valve opens.
- Fuel and air get into the cylinder.
- Inlet valve is closed.
- Piston moves up the cylinder.
- Fuel-air mixture is compressed.
- A spark is produced at spark plug, igniting the fuel-air mixture.
- The increased pressure forces the piston down the cylinder.
Exhaust Stroke –
- Exhaust valve opens.
- Piston moves up the cylinder.
- Burned fuel-air mixture expelled.
Advantages of the Four Stroke Engines
- Produce high power which can do heavy farm work.
- Have efficient fuel and oil utilization.
- Perform a wide range of farm operations.
- Are effectively cooled with water thus allowing the production of large engine size.
- Exhaust gasses are effectively expelled from the cylinders.
- Are expensive to buy and maintain
- Their use is limited in some areas;
- Tractor can only be used on flat or gently sloping areas
- Require skilled personnel and support services
The Two Stroke Engines
- Found in small machines such as mowers, motor bikes, and water pumps which do light jobs in the farm.
- All the cycles are completed in two strokes of the piston.
These strokes are;
Induction and compression stroke
- The piston is at the bottom
- Piston moves up uncovering the inlet port
- Fuel-air mixure is drawn in
- Ignition occurs when the piston reaches the top
- Piston is forced downward compressing the mixture in the crank.
Power and exhaust stroke
- The piston is at the top
- Ignited gases produce pressure which force the piston downwards
- The piston covers the inlet port and traps fresh fuel-air mixture in the crank case
- Piston moves further down to uncover the exhaust port
- Fuel-air mixture transferred from the crankcase to the combustion chamber.
What Advantages of two stroke engine?
- Cheap to buy and easy to maintain
- Economical in fuel consumption
- Can be used in a wide range of farmland, including hilly areas
- Can do small tasks in the farm which would be un-economical to do using the four stroke engine.
What disadvantages of two stroke engine?
- They produce less power hence cannot be used for heavy duties.
- They are inefficient in burning fuel to produce power.
- They are air cooled thus limiting the size of the engine.
Systems of a Tractor
The modern tractor has the following systems:
- The fuel system.
- Electrical system
- Ignition system
- Cooling system
- Power transmission system.
The Fuel System
Supplies fuel to the engine.
Categorized into two types depending on the fuel used.
- The petrol fuel system.
- The diesel fuel system
The Petrol Fuel System
- Fuel tank – storage of fuel.
- Fuel filter – removes foreign particles from the fuel.
- Carburettor –
- atomises fuel into spray.
- introduces fuel-air mixture into the engines.
- Regulates fuel-air into suitable proportion
- Fuel pump – forces fuel into the carburettor.
- Delivery pipe – connects all the devices.
- Cleaning the carburettor regularly.
- Cleaning the fuel filter in petrol.
- Cleaning the hole in the fuel tank cap.
The Diesel Fuel System
- Fuel tank – storage of fuel.
- Fuel injection pump – pumps diesel through injection nozzles and breaks into fine spray.
- Fuel filters – remove foreign particles from the fuel.
- Delivery pipes – connect the various devices.
- Replacing the fuel filter.
- Bleeding in case air is trapped in the system.
- Cleaning the sediment bowl regularly.
Structural and Functional Differences Between Petrol and Diesel Engines
|Petrol engine||Diesel Engine|
|· 1.||· It has a carburettor||· 1.||· It has an injection pump.|
|· 2.||· Fuel and air are mixed in the carburettor||· 2.||· The fuel and air are mixed within the|
|·||before it gets into the engine.||·||cylinder.|
|· 3.||· Fuel is ignited by an electric spark.||· 3.||· Fuel is ignited by compression of air and|
|·||·||fuel mixture in the cylinder.|
|· 4.||· It produces little smoke because||· 4.||· It produces a lot of smoke since the diesel|
|·||petrol is completely burnt.||·||is not completely burnt.|
|· 5.||· Petrol engine is light in weight and||· 5.||· It is relatively heavy in weight and suited|
|·||suited for light duties.||·||for heavy duties.|
Consists of the following:
- Converts chemical energy into electrical energy.
- Stores electrical energy produced by the running
- Ignition circuit – provide the electrical required by the spark plugs.
current that produces a spark in the engine.
- Generator circuit – provide the electrical current that starts the engine.
- Lighting circuit – supply the electrical current required for the lighting system.
- Starter motor circuit – starts the engine.
Care and Maintenance of a Tractor Battery
- The level of electrolyte should be kept just above the plate by topping with distilled water.
- Corroded terminals should be scrapped clean and smeared with grease.
- The battery should be tightly fixed in a box to avoid spillage and damage.
- The battery should be fitted correctly on the tractor.
- The battery should be charged regularly and periodically.
- In case of long storage the battery contents should be kept upside down.
- The generator fan belt should always be functional to ensure the battery is always charged.
- Ignition – change the low voltage from the battery to high voltage current required by the spark plugs.
- Condenser – absorbs the self-induced current in the primary circuit.
- stores current for a short time.
- passes electric current to the distribut
- Distributor – distributes the high voltage current to the spark plugs.
- Contact breaker – Interrupts the normal flow of current in the primary circuit.
State the Maintenance practices carried on the Ignition System
- The carbon deposits on the spark plug electrodes should be removed.
- The spark plugs whose electrodes are worn out should be replaced.
- The contact breaker points should be cleaned.
- The breaker points should be adjusted so that they lie between O.30mm and 0.50mm.
- The condenser should be replaced regularly.
- The ignition systems should always be kept dry.
- Ignition wires with poor insulation should be replaced.
- The cooling system aims at preventing the engine from overheating which would cause piston zeisure in the cylinder.
- Some tractor engines are cooled by air while others are cooled by water.
State the Characteristics of Air Cooled Engines
- They are simple in construction.
- They have fins and a fan blade which assists the circulation.
- They are light in weight for they have no radiators and water jack
- They get hot quickly and use heavy lubricating oil.
- The cooling is not adequate under all conditions especially when carrying heavy load
Water Cooled Systems
- It consists of the radiator, water jackets, water hoses, water pump, thermostat and a fanning mechanism.
- Water is used to absorb heat from the engine block at a reasonable rate.
Care and Maintenance of Water Cooling system
- The water pumps should be lubricated regularly.
- Clean water should be used in the radiator and trash removed from the fins.
- All pipes should be fitted tightly to avoid blockage.
- The radiator should be filled with clean water before starting the day’s work.
- Fan belt tension should be checked regularly and if too tight or too loose should be adjusted accordingly.
- This system is aimed at supplying oil to all parts of the engine where friction is likely to occur.
Importance of Lubrication system
- It helps to increase the efficiency of the machine and reduces the rate of wear and tear of moving parts.
- It reduces the heat created by the rubbing surfaces and acts as a seal between them.
- It acts as a cleaning agent because it washes off all the dust, dirt, soot and metal chippings from the oil paths to the sump.
Types of Lubrication Systems;
- Splash feed type
- Force feed type
- Oil mist type
Types of Lubricants
- SAE 10 – This is thin engine oil which gives little protection when heated.
- SAE 50 – This is thicker engine oil which is recommended for protecting the bearings.
- SAE 90 – 100 – These are transmission oils which are recommended for clutch, gear box, wheel lubrication and ball bearings.
Note: SAE – Society of Automobile Engines.
Care and Maintenance of Lubrication Systems
- Old or contaminated oil should not be used for lubrication.
- Oil should be drained when still hot to avoid sticking on the walls of the sump.
- The oil filters should be replaced when necessary.
- The correct type of oil should be used as per the manufacturers’ instructions.
Power Transmission System
- The function of this system is to transfer power from the tractor engine to the drive shaft, the wheel axle, the power take off shaft and the hydraulic system.
- The system consists of the clutch, gear box, differential and the final drive.
The power transmitted from the engine is made available for use through the following:
- The propeller shaft – it connects the gear box to the differential.
- The power take off shaft (PTO shaft) -It is located at the rear part of the tractor and rotates at the same speed as the crankshaft of the engine.
- Hydraulic system – it is operated by the use of a lever near the drivers seat.
- It is connected to the 3-point linkage and helps to lower or raise implements mounted on the 3-point linkages such as ploughs, mowers, planters and sprayers.
- Draw bar –
- It is a one-point linkage at the rear part of the tract
- It serves for the attachment of trailed implements that can be used during harrowing, transportation or rolling.
- The aim of tractor servicing is to keep the tractor in good and efficient working conditions.
- Tractor servicing is either;
- long term.
List the Short Term Tractor Servicing
- Checking the engine oil daily by use of a dip stick.
- If the oil level is low, it should be added.
- The fuel level should be checked at the start of every day’s work and added if necessary.
- Water level in the radiator should be checked and if possible topped up.
- The level of the electrolyte should be checked daily and topped up with distilled water accordingly.
- Nuts and bolts should be tightened every day.
- Lost nuts and bolts should be replaced before the day’s work.
- Grease should be applied by use of grease gun through the nipples.
- Large sediments from the sediments bowl should be removed.
- The tyre pressure should be checked daily before the day’s work.
- The fan belt tension should be checked to ensure that it deflects between 1.9cm and 2.5cm when pushed.
- The brake shaft bearing should be greased.
- The brake fluid level is maintained at the recommended level.
Long Term Services
- The engine oil should be drained completely from the oil sump and replaced with new oil.
- The gear box oil should be checked and refilled as recommended.
- The oil in the differential should be replaced as recommended.
- The linkage and the pulley attachment should be greased.
- The pulley oil level should be checked and added if need be.
- The dirty oil should be removed and replaced with clean one.
Tractor Drawn Implements
- These are implements which are attached to the tractor during opera
State the two categories. Tractor Drawn Implements
- One–point hitch implements ;
- Are attached to the tractor at only one point that is, the draw bar.
- They include all trailed implements such as the trailers, heavy harrows, planters and roller
- Three point hitch implements;
- Are implements attached to the tractor at three points that is, the top linkage point and two lower linkage point
- They are operated by the hydraulic system.
- They include ploughs, most harrows, subsoiler, planters, mower, ridgers, sprayers and rotavators.
- They are one-point hitch implements.
- They are used for transportation of goods.
- Small ones have two wheels while big ones have four wheels.
- All the moving parts should be lubricated.
- Tyre pressure should be adjusted to the correct pressure.
- Worn out tyres should be replaced.
- Loose nuts and bolts should be tightened, worn-out ones should be replaced.
- The implements should be kept under a shed during long storage.
- They are primary tillage implements.
- The common type of ploughs include:
- Disc plough
- Mould board ploughs.
- It is made up of heavy steel concave discs of 60-70cm diameter.
Parts and Functions of a disc plough
- The hitchmast:
- Is an attachment for the three point hitch.
- Made up of two side links and a top link.
- These are parts connected to hydraulic system of a tractor for lifting and pulling.
- The beam: Supports all other parts. It also adds weight for better penetrati
- Depth wheel:
- Used when driving on highway,
- it also controls the depth of plou
- May not be present in all disc ploughs.
- The standard or leg: Connects the discs to the beam.
- The hub: Allows the discs to rotate smoothly hence does the cutting of furrow slices.
- The scrapers: Remove the trash and mud or soil which cling to the discs,
- Disc blades: Cut and invert the furrow slice
- Rear furrow wheel: Controls the depth of digging and stabilises the discs.
- The cutting angle should be adjusted at 35° – 50° from the I ine of travel.
Achieved by pivoting the beam or the standard.
- Depth of digging: This is corrected by changing the height of depth wheel or adjusting hydraulic system and adding weight
Care and Maintenance of Disc Plough
- Check for loose nuts and bolts and replace them.
- Sharpen the disc blades if blunt.
- Lubricate the rotating parts by use of oil/grease to reduce friction.
- Paint the exposed parts for example the beam/framework.
- Clean the implement at the end of each day’s work before storage.
- Store the implements in a shed.
- The unpainted parts should be coated with old engine oil to prevent rust.
Uses of a Disc Plough
Used in areas with the following conditions:
- Virgin land with many obstacles.
- Land with too much trash or tall vegeta
- Opening up pasture land.
- This primary tillage implement is suited in areas without obstacles such as stones, tree stumps, and roots.
- It gives a uniform depth of ploughing.
Parts and Functions Mouldboard ploughs
- Share: This makes the horizontal cut and starts the turning of the furrow slices.
- Mouldboard: Continues the turning of the furrow slices and pulverizes the soil.
- Disc coulter: Makes a vertical cut in the soil to separate the furrow slice from the un-ploughed land.
- Skim coulter: Removes any trash from between the furrow slices.
- Frog: It is the part where the share, mould board and the landside are attach
- Landside: Stabilizes the plough and absorbs the side forces created when furrow is turned.
- Shin: Leading edge of a mouldboard.
- Knife coulter: Is a vertical knife which cuts trash and earth ahead of the share.
Care and Maintenance
- Lubricate the rolling parts for example wheel bearings and disc coulter bearings.
- Paint scratched parts of the plough.
- Sharpen the share or replace if worn out.
- Check all loose nuts and bolts and replace where necessary.
- Clean the implement after each day’s work to remove soil, mud and trash.
- For long storage, keep under a shed and apply lubricants.
- Controlled by raising or lowering the depth wheel.
- Controlled by hydraulic control lever setting.
- Pitch: controlled by altering the length of the top li
- Front furrow width: Controlled by cross shaft adjustment lever or by rotating the cross shaft crank.
- Lateral levelling: Controlled by tractor lift rod.
Operational differences between a disc and a mouldboard
|Disc Plough||Mouldboard Plough|
|· 1.||· Suitable on field with stones,||· 1.||· Cannot be used on fields with stone,|
|·||roots and stumps.||·||roots or stumps.|
|· 2.||· Does not invert the furrow slices||· 2.||· Inverts the furrow slices completely.|
|· 3.||· More secondary operations are||· 3.||· Fewer secondary operations are|
|·||necessary after it has been used.||·||needed.|
|· 4.||· Cuts at varying points.||· 4.||· Operates at uniform depth.|
|· 5.||· Not easily broken by obstacles.||· 5.||· Can easily be broken by obstacles.|
- They are secondary cultivation implements.
- There are different types of harrows.
- The common ones are:
- disc, Harrows
- spring tine Harrows
- spike tooth harrows.
- It comprises of a set of gangs with concave discs.
- Mixing the soil particles.
- Levelling the seedbed by breaking large
- lumps of soil.
- Killing weeds.
Disk harrows can be classified according to the arrangement of the gangs such a;
- s tandem,
- double tandem
- offset tandem.
- Adding weights on the harrows.
- Use of hydraulic force.
- Use of light or heavy harrows.
- Use of regulating wheels.
Care and Maintenance
- Check for loose nuts and bolts daily.
- Lubricate the shafts and bearings.
- Clean and oil before storage.
Spring Tine Harrow
- Is made up of flat and curved tines which act as springs.
- Levels and smoothens the seedbed.
- Breaks the soil clods.
- Mixes trash and soil thus preventing wind erosion.
- Aerates the soil.
- Depth is controlled by the horizontal connecting link and depth wheel.
- For individual tine, use crossbar and loosening the screws.
Care and Maintenance
- Check for loose nuts and bolts and tighten them if necessary.
- Clean after use.
- Oil the lever mechanism.
Spike Tooth Harrows
- Consists of a metal framework with rigid metal spikes which break up the soil by vigorously hitting large lumps of soils as it is pulled through the soil.
- It smoothens and compacts the soil.
- It breaks big lumps of soil into small particles.
- Can be used for cultivating small crops if well set.
- Heavy and require high horse power to pull.
- Ploughing depth of 51-90cm.
- Break up compacted soil.
- Break up the hardpan.
Care and Maintenance
- Clean it after use
- Check the point and if worn out, replace it.
- Oil when not in use.
- It is double mould board plough used to make ridges and furrow
- It is used to prevent water logging and draining through furrows for easy harvesting of root crops.
- This is an equipment used to compact the soil gently especially where tiny seeds are to be planted.
Rotavators: (Rotary cultivators)
- Work on the principles of high speed of revolving flail blades which beat and cut the soil together with trash.
- It is an equipment for both primary and secondary tillage operations.
- It is driven by the P.T.O. shaft of a tractor.
- Breaks up large soil particles into small ones.
- Mixes the vegetation and the soil.
- Achieves two operations in one pass.
- Forward speed of the tractor gives a fine tilth of the seedbed done through the gearbox.
- Depth of work done by control of depth wheel.
- Slip clutch may break in case the knives come across obstructions
- Cutting grass for hay or silage making,
- cutting overgrown grass
- clearing the field.
Parts and Functions
- Swath stick: Keeps the cut crop falling correctly.
- Swath board: To remove the cut crop.
- Shoe: Has a runner to absorb the weight and wear.
- Cutter bar: Is a flat bar which guides the fingers.
- Wear plate: Counteracts downward force and holds the knives.
- To adjust knife register by moving the whole bar away or towards the yoke.
- Knife lead: The outer shoe should be adjusted to be outer than the inner shoe by 4cm.
- Check for loose nuts and bolts and tighten where necessary.
- Keep knife section sharp.
- Lubricate the knife parts.
- Check knife to ledger plate cup for best cutting.
- Keep all the parts tight.
- Cutting edge consists of two blades fitted opposite to each other on horizontal disc.
- The cutting blades swing round at high speed horizontally to the ground hence cutting is effected.
Adjustment and Maintenance
- Blades should be sharp.
- Guards to be fitted around the blades to protect the operator from flying objects.
- Lubricate the P.T.O. shafts.
- Check the gear-box oil regularly and fill to the right level if necessary.
- They are machines used for sowing seeds.
- There are two types:
- Row crop planters.
- Seed drills.
Functions of the Planters
- Meter the seed and fertilizers from seed and fertilizer
- Open the seed furrow.
- Deposit the seed in the furrow through the delivery tubes.
- Cover the seed
Functions of Parts of a Seed Plate
- Filler plate: gives proper seed depth.
- False ring: allows the seed to fall from the seed plate into the boot.
- Knockout pawl: pushes the seeds out of the cell by the roller action.
- Cut-off pawl: prevents more than one seed remaining in a plate cell.
- Cells: shaped holes to hold the seed.
- Adjust the coulters depth for the right crop.
- Fix the right seed plate.
- Place the planter in the level position.
- All the shafts should be free to turn.
Care and Maintenance
- Check all loose nuts, bolts and tighten them.
- Clean and oil the planter after use.
- Grease the drive sprockets regularly.
- The grain drill sows grains of wheat, barley, oats, peas, beans and alfalfa seeds.
Parts that can be adjusted to change the sowing rate;
- Select the side of the feed wheel recommended on the drill charts for the seed-rate.
- Change the speed of the wheels by changing the gears or sprockets or both.
- Change the position of the feed gate in the cup.
- Use reducers below the feed wheel.
Care and Maintenance
- Keep seed and fertilizer hoppers dry and clean after each day’s work.
- Check the drive shaft and lubricate them.
- Paint the parts for example fertilizer
- hopper to be shiny
- Harvesting cereal crops for example maize, wheat and barley.
It is designed to do the following:
Parts of a Combine Harvester
- Cutter bar – cuts the grain head.
- Pick up reel- direct crop into the cutter bar,
- Elevator – channels the cut grain to the threshing drum.
- Winnowing ran – fans trash up onto a straw walker and directs it out of the combine harvester.
- Delivery tube – delivers the clean .grains into a collecting tank from where it is bagged.
Maintenance of a Combine Harvester
- Loose nuts and bolts should be tightened.
- Remove all foreign materials stuck in the machine at the end of the day’s work.
- They are used for harvesting tuber crops and for making furrows or ridges.
- Lubricate the moving parts.
- Clean the implement after use.
- Store under a shed.
- Repair or replace worn-out or broken parts.
- Loose nuts and bolts should be tightened.
- Unpainted parts should be oiled during long storage.
- Shares should be sharpened if blunt.
- They are tractor mounted and operated by power from the P.T.O. shaft .
- Used for harvesting forage crops such as Napier grass, sorghum and maize.
- Tighten loose nuts and bolts.
- Lubricate moving parts.
- Store in a shed.
- Clean after the day’s work.
- Repair/replace worn out or broken parts.
- Unpainted parts should be oiled to prevent rust.
- These are stationary implements which are either hand or tractor driven.
- They consist of. a rotating disc which shell maize grains from cobs.
- Greasing moving parts.
- Removing any stuck maize cobs.
- Repair or replace worn out or broken parts.
- Store in a shed.
Animal Drawn Implements
- Ox-plough is a simple type of a mouldboard plough which is pulled by a pair of oxen, donkeys or camels.
Explain the functions of the following parts of an ox-plough
- Main beam – It is the main component onto which all the other parts are attached.
- Mouldboard – It inverts the cut furrow slice upside down.
- Plough share -It cuts the furrow slices.
- Land wheel- It regulates the depth of plough.
- Draft rod – It is on this rod that a chain is connected on which a yoke is linked.
- It forms the draught mechanism of the plough.
What are the Advantages of an Ox-Plough Over Tractor Drawn Plough ?
- Less skill is required to operate it.
- Useful where tractors cannot be used for example steep slopes.
- Cheap to buy and maintain.
What are the disadvantages of an Ox-Plough Over Tractor Drawn Plough ?
- Much time is wasted in training oxen.
- Tedious and laborious to the driver of the animals and the controller of the implement.
- Animals can be sick or in poor physical state.
- Extra land is required as grazing fields for the oxen.
- Depth of plough is controlled by the land wheel and draft rod
Care and Maintenance
- Sharpen or replacing of the worn out share
- Replacement of worn out parts such as hooks and draw bar assembly.
- Oiling the shiny parts e.g mouldboard
- Wash off the soil after use.
- Paint the handles, beam and braces to prevent rusting.
- These are small carriages harnessed to the animals by a yoke
- The small carts have only two wheels bigger ones have four.
- They are pulled by animals in singles or in pairs
- Carts are used for transport.
- Moving parts should be oiled
- The yoke should be repaired when worn out or replaced if not repaired
- Tyre pressure should be checked and adjusted accordingly
- Repair other damages on the cart.
Agricultural Economics III:
- The agricultural sector is a key player in the economy of our countr
- It is a major employer and brings a lot of national income through foreign exchan
- These are the total earnings from goods and services produced by a country in a period of one year.
Relationship Between Firm and Household
- A household is considered to be a unit comprising a farmer and family members.
- It produces raw materials and consumes manufactured goods.
- A firm on the other hand, is any manufacturing or processing unit which consumes raw materials and produces manufactured good
- Both household and firm generate income, which in turn, is used to:
- Improve the standard of living of the household members by paying for essential goods and servi
- The firms build more industries to create more employment and revenue through salaries and wages.
- Finance government projects through taxes and hence further national development.
Gross Domestic Product (G.D.P.)
- This is the sum total of all goods and services produced in a country in a period of one year.
Gross National Product (G.N.P.)
- Is the sum total of G.D.P. and the difference between income inflow (revenue coming into the country from outside) and income outflow (money going out of the country by foreign investors).
- It represents the total income earned within the country and from abroad.
Per Capita Income
- Is the Gross National Income (in terms of revenue) divided by the number of people living in the cou
- It is not a good measure of the economic well-being of the people because of the uneven distribution of income among th
Contribution of Agriculture to National Development
- The interaction between household and the firm generate income which is used to finance further expansion of the firms.
- This creates more employment and revenue.
- The government taxes the income to finance national development programmes such as;
- water, energy
Factors of Production
- A factor of production is anything that contributes directly to output, that is, it is a productive resource.
- Productive resources usually employed in the production of goods and servi
- As a factor of production, refers to the natural characteristics and properties of a given area of land.
- The key factor here is productivity for example soil fertility, presence of water and minerals and is always fixed and has no geographical mobility.
- Besides being a consumer, human beings are also a factor of productio
- They provide the labour force (human power) required in the production process.
- Labour is assessed in terms of productivity and not mere numbers of workers or labourers.
- Labour is measured in terms of man hours, man days or man mon
The labourer’s productive capacity depends on such factors as;
- state of nutrition
- level of education.
- The amount of work and the efficiency with which it is performed determines the quality of labour.
- Capital refers to all man-made assets that help land and labour to produce.
- It is categorized into:
- Working capital
- Liquid capital
Capital for example
- permanent improvements on land like fences,
- irrigation facilities
- water supply system.
Which include consumer goods such as;
- livestock feeds,
- fuel in store,
- ready money,
- bank deposits,
- shares in financial i
- It is a process of decision making in the farm.
- Managers use their knowledge and judgment to decide how to combine the other three productive resources in the best way possible.
- They make plans, execute them and bear the risks or consequences which such plans entail.
- Production function is a physical relationship between inputs and outputs in a production process.
- It tells the quantity of output (product) that may be expected from a given combination of inputs.
- Production function may be expressed in table form or graphically as a curve.
Feeding pigs for pork production at varying levels of concentrate feed.
|Unit of feed||Body wt.||Marginal|
Types of Production Functions
- A production function assumes three forms which may be treated as different types:
- Increasing Returns
- Constant Returns
- Decreasing (Diminishing) Returns
- In this type, each additional unit of input results in a larger increase in output than the preceding unit.
- This shows that resources are under utilized.
- The amount of the product increases by the same amount for each additional input; that is constant returns to input factor.
- Again here resources are under uti
Decreasing (Diminishing) Returns
- Here, each additional unit of input results in a smaller increase in output than the preceding unit.
- Resource use is stretched to the maxi
- It is the most commonly encountered form in agricultural enterprises;
- It gives rise to the law of Diminishing Returns.
- Feeding dairy cows for milk production with varying amounts of feed.
- Crop responses to application of varying amounts of fertilizers.
- Use of varying units of labour on fixed unit of land.
Economic Laws and Principles
The Law of Diminishing Returns
- The law of diminishing returns states that;
’’if successive units of one input are added to fixed quantities of other inputs a point is eventually reached where additional product (output) per additional unit of input declines.’’
- This law is encountered practically in all forms of agricultural production.
- It is useful in determining the most rational and profitable level of production.
Production of maize at varying levels of N.P.K. fertilizer application on a fixed area of land.
|Unit ofNPK||Total Product||Marginal|
Zones of a production function curves
Zones of a production function curves these are:
- Irrational zone or Zone I.
- Rational zone or Zone II
- Irrational zone or Zone III.
- The three zones are arrived at by drawing two perpendicular lines through the production function curve, one at MP = AP and another at MP=
- In Zone I resources are not fully utilized while in Zone III, excessive application of resources leads to production decline or loss.
- It is not economical to produce at these levels.
- In Zone II resources are maximally utilized resulting in maximum production.
- It is therefore economical (or wise) to produce at this level.
Principle of Substitution
States-’’if the output in a production process is constant, it is profitable to substitute one input factor for another, as long as it is cheaper than its next alternative.’’
- This principle is applicable in a situation where more than one variable input factors are used.
- For example feeding hay and concentrates for milk production, farmyard manure and phosphatic fertilizers in the production of maize.
- The basic problem that the producer wishes to solve when two input factors are used in combination is in what proportions must the variable inputs be combined in order to produce at a minimum cost and hence attain maximum profit.
- To solve the above problem, the producer must determine the least cost combination of inputs used.
- The least cost combination is attained at a point where the Marginal Rate of Substitution (MRS) equals the inverse of price ratio of the factors involved.
x2 = P X1
X1= P X2
X1 – first input factor
X2– second input factor
– change (increase or decrease)
P – price (cost of input fators)
- Producing 20 bags of maize using varying combinations of farmyard manure and phosphate fertilizers.
- Price of farm yard manure (FYM) is KShs10/- per unit and that of phosphate fertilizer is Kshs 50/- per unit
|X1 (P-fert)||x2 (N-fert)||X2(MRS)
|100kg units||100kg units|
In the above example, the following assumptions are made:
- A fixed quantity of output is to be produced.
- Input factors in combination substitute for one another at varying rates.
- Relative prices of input factors do not change drastically during the period of production.
NOTE: one input factor substitutes for the other at diminishing varying marginal rate of substitution.
Principle of Equimarginal Returns
- This principle states ;’’ That the last unit of an input factor spent in one enterprise yields a marginal return exactly equal to the marginal return earned from the last unit invested in each of the other enterprises.’’
- If the last shs.100/- spent buying cattle feed will return more than shs. 100/= spent on buying fertilizer for growing maize, then it is advisable to purchase more feed up to a point where the last shs.lOO/- spent on it will return exactly the same as the last shs.100/- spent on fertilizers.
- This concept is only relevant in a situation where farmers do not have adequate capital to employ inputs up to the level where marginal revenue equals the marginal cost.
The principal of Profit Maximization
- The profit is defined as the difference, in monetary terms, between the total returns (income) and total costs (expenses) in a production process.
- Profit maximisation aims at obtaining the highest returns at a minimum cost per unit of input factor used.
- This can be done by considering two concepts.
- Profit is maximised when the marginal (additional or extra) revenue (MR) is equal to, or slightly higher than, the marginal cost (Mc).
- At this point every added input factor brings in higher returns than the expenses incurred in investing it.
Net Revenue Concepts
- Profit is said to be maximized in a production process when the Net Revenue (differences between total revenue and total costs) is the highest that is ;
NR = TR – TC.
- This is arrived at by analyzing the total cost and total revenue earned from a particular enterprise and then subtracting the former from the latter.
When calculating the profit using whatever concept, the following assumptions are made:
- Cost of inputs (such as fertilizers, labour) remains constant during the period of production.
- Price of the produce (product) remains unchanged.
- Fixed costs are ignored that is only varying costs directly involved are considered.
- Planning is the process of establishing the organizational objectives and defining the means of achieving them.
Factors to consider in drawing a farm plan.
- Size of the farm.
- Environmental factors.
- The current trends in labour markets.
- Farmer’s objectives and preferences.
- Possible production enterprises.
- Existing market conditions and price trends.
- Availability and cost of farm inputs.
- Government regulations/
- Communication and transport facilities
- Farm budgeting is the process of estimating the future outcomes of a proposed farm plan,
- That is; the future incomes and expenses of a farm plan.
Importance of Farm Budgeting
- It helps the farm in decision making.
- It helps the farmer to predict future
- returns that is planning ahead.
- It helps the farmer to avoid incurring losses by investing in less profitable enterprises.
- It helps the farmer to secure loans from financial institutions such as Agricultural Finance Corporation and commercial banks.
- It ensures a periodic analysis of the farm business.
- It acts as a record which can be used for future reference.
- It pinpoints strengths or weaknesses in farm operations.
Types of Budgets
- It represents financial effects on minor changes in a farm organisation.
- It is necessary when a farmer wants to replace or reduce enterprise.
- A complete budget is necessary when the farmer wants to start a new business where both the variable costs and the fixed costs are likely to be affected.
- It involves a major change or reorganization in the farm business.
Agricultural Services Available to the Farmer:
- Agricultural production efficiency is greatly increased by services rendered to the farming communities by;
- Government institutions
- Non-governmental organizations.
Some of these services are:
- Extension and Training:
- Banking Services:
Extension and Training:
- In the field and in farmer’s training centres.
- These enables the farmers to save some of their farm income and invest them in future projects.
- Credit is a financial assistance advanced to agricultural farmers to finance their farm projects and repay it with interest.
- It is a borrowed resource.
Types of Credit
- Credit is categorised according to;
- Time of repayment
- The types of projects to be financed.
- Repayable within one year and is advanced for the purchase of;
- animal feeds .
- Repayable within 2 – 5 years and is used to finance projects such as;
- fencing materials,
- purchase of livestock,
- light farm equipment .
- Repayable period is up to 15 years and even more.
- It is given for the long-term or durable projects such as;
- purchase of land,
- construction of soil and water conservation structures,
- farm buildings,
- irrigation projects for perennial cash crops for example;
- farm machinery
Sources of Credit
- Co-operative societies and unions.
- Crop boards.
- Commercial banks.
- Agricultural Finance Corporation.
- Insurance companies.
- Individual money lenders.
- Settlement fund trustee.
Artificial Insemination Services:
- Provides farmers with semen from improved or superior bulls to improve their livestock herds through controlled breeding.
Agricultural Research Organization
- These develop and pass on to farmers, improved production techniques as well as crop and livestock species with better performance in different ecological zones.
- These are agencies that ensure effective and efficient conveyance of farm produce to points of processing and consumption.
- They are largely crop marketing boards or corporations and cooperative societies.
- In the field are veterinary officers who help the farmer in treating and controlling livestock diseases and parasites.
Farm Input Supplies
- Farmers are able to obtain their farm inputs from organizations such as co-operatives and private companies.
- These organizations bring inputs closer to the farmers for example Kenya Farmers Association and private agro
Tractor Hire Services
- This involves hiring of tractors and machinery at a cost by farmers who are not privileged to own their own.
- Ministry of Agriculture
- Private contractors.
- Individual farmers.
- Other service providers.
Risks and Uncertainties in Farming
- Uncertainty–is the state of not knowing about future events or outcomes.
- Risks-is the difference (divergence) between the expected and the actual
Types of Risks and Uncertainties
- Fluctuation of commodity prices.
- Physical yield uncertainty.
- Ownership uncertainty.
- Outbreak of pests and diseases.
- Sickness and injury.
- New production technique.
- Obsolescence for example machinery may become outdated or obsolete within a short time.
- Death of either farmer or lives
- Natural catastrophies such as;
- storm and strong winds which may destroy crops or kill the animals.
Ways in Which Farmers Adjust to Risks and Uncertainties
- Selecting more certain enterprises.
- Input rationing.
- Flexibility in production methods.
- Adopting modern methods of production.
Agricultural Economics IV:
- Financial and physical records if accurately kept in the farm serve as very important tools in decision-maki
- The records are kept in several books and statements as follows:
- Delivery notes
- Purchase records.
- This is a document issued by the seller to the buyer for goods taken on credit, and payment to be done later.
- The original is given to the buyer and duplicate retained by seller.
The invoice shows the following:
- The buyer and seller.
- Date of transaction.
- Amount involved.
- Invoice number.
- This is a document issued by the seller to the buyer when cash payment for goods delivered is made.
It shows the following:
- The buyer and the seller.
- Date of transaction.
- Amount involved.
- Serial number
- It is a document which shows that the goods have been delivered.
- The receiver verifies the goods and then signs on the delivery note.
The delivery note shows the following:
- Goods delivered as per order.
- Quality or condition.
- People involved in the transaction.
- Date of delivery.
- It is a book of first entry showing a record of all business transactions arranged in the order in which they occur.
- Its pages are divided vertically into five sectio
- The information is posted to the ledger
- This is a list of all the possession/assets item by item and their market value.
- Such items are land, livestock, tools and equipment and crops in the store.
- Valuation is an estimation of the value of each asset or item, based on market price or cost of production.
Local Purchase Order:
- Issued by the purchasing officer of the supplier for example school.
- It shows people involved in the transaction, types and amounts of goods ordered and dates.
- It should be written and signed by the authorised officer.
- It is written in duplicate and the original is given to the supplier.
- Is a book which contains individual accounts.
- It is a principle book of accounts in which entries contained in all the other books are enter
- It is a storehouse of all the transactions.
- Each page is numbered and vertically divided into two equal parts namely credit and debit.
- Each part is further sub-divided into four sections.
- It is a book where transactions involving cash or cheque payments are record
- It involves cash or cheque payments and receipt
- It is divided into two parts – debit and credit side.
- All the receipts of cash or cheque are recorded on the debit and all payments are recorded on the credit
Example: Enter the following entries in the cash book.
- 1.05 -Received shs.2,000 from Ndete by cheque.
- 7.05-Bought D.A.P. fertilizer and paid cheque of shs. 5,000.
- 7.05-Received shs.5,000 cash from Ngala.
- 4.7.05 -Paid water bill for shs 400 in cas
- 7.05-Paid telephone bill of 1,500 by cheque.
- 11.05 -Deposited shs.2,000 in the bank.
- 20.7.05 -Withdrew shs.2,000 from the bank for home use.
Cash Book record
|1.7.05||Received from Ndete||2,000||2.7.05||D.A.P||5,000|
|3.7.05||Received from Ngala||5,000||4.7.05||Water bill||400|
Cash Account Sheet
- It involves the recording of sales and receipts, purchases and ex
- Each sale or purchase is entered twice, once in the total column and once in the analysis column.
- The sum of all the entries in the total column should always equal the sum of the entries in all the other columns.
- The cash analysis account sheet is given above.
The Balance Sheet
- It is a financial statement of assets and liabilities recorded on a given date.
- It shows the financial position of a farm business at a glance (snapshot).
Assets are items owned by the farmer,
- Property (money, goods and buildings).
- Debts receivable from other people.
- Goods and services paid for in advance.
Assets can be divided into two:
- Fixed assets: assets of permanent nature and not easily converted into cash.
- Current assets: assets which can be easily converted into cash.
- Liabilities are claims to the farmer’s property such as bank overdraft and debts payab
They are divided into:
- Current liabilities – debts which must be paid within a short time.
- Long term liabilities – debts which are payable over many years or over a long period.
Profit and Loss Account
- Prepared at the end of a calendar year.
- It is a final account which summarises the sale and receipts (income flowing in the business) and the purchases and expenses (flowing out of the business).
- Note: If assets are more than liabilities then the balancing factor is net capital (in the liability side) hence the farm business is said to be solvent.
- If the liabilities are more than the assets, then the balancing factor is a loss (in the asset side) hence the farm business is insolvent.
- To calculate profit or loss, account, valuation is done by having an inventory of all the assets.
- Valuation of the assets is determined by market price and cost of production for machinery and buildings as depreciation factor, is attached.
Format of a balance sheet
Balance sheet of Katilo school as 31-12-2009
|Fixed Assets||Long-term Liabilities|
|Land||Long-term loan for land development|
|Buildings||Loans payable over 15 years|
|Fences and other structures|
|Current Assets||Current Liabilities –|
|Debts receivable||-Credits from friends|
|Cash in bank||-Short-term loans|
|Cash in hand|
Profit and Loss Account of Kitheko Farm at 31–12–2009
|Sales and Receipts||Shs.||Cts.||Purchase & Expenses||Shs.||Cts.|
|I.||Income during the year||I.||Opening valuation|
|2.||Debts receivable||2.||Expenditure during the year|
|3.||Closing valuation||3.||Debts payable Balance (being|
|Balance (being a loss)||farm a profit or net income)|
Agricultural Economics V
(Agricultural Marketing and Organizations)
- Agricultural marketing is an economic activity which involves the distribution of farm produce from the farm to the consumer.
Market and Marketing
- Market is an institution for the exchange of goods and services or a place where selling and buying of goods takes place.
- Marketing refers to the flow of goods and services from the producer to the consumers.
- Transportation – Movement of goods from production centres to the consumption centres.
- Buying and selling – Purchase of goods from the producer to be sold to the consumer.
- Storage – Agricultural products are seasonal hence storage is necessary.
- Processing-Changing of raw form into utili sable form.
- Grading and standardisation – Sorting into uniform lots of certain qualities.
- Assembling – Collecting the farm produce from the farm to the market centres.
- Collecting market information – To know the prices, supply and demand of certain commodities.
- Advertising – Making the consumers aware of the produce.
- Bearing of risks – Such as fire risk, price fluctuation.
- Financing or expenditure on other processe
- Packaging or putting into small packs and labelling.
- Packing or putting produce In containers such as bags.
Marketing Agencies and Institutions
- Middlemen (itinerant trader) – are the people who buy from the producer and sell to other agencies.
- Wholesalers – Buy in bulk and sell to the retailers.
- Retailers – Buy from the wholesalers and sell in small units to the consumers.
Problems in Marketing Agricultural Produce
- Farm produce are bulky, that is weight and volume are high but low in monetary value thus difficult to transport.
- Most of the agricultural products are perishable for example milk, vegetables and fruits.
- Storage problems (since they are bulky they require a lot of space).
- Lack of proper transport system since agricultural products are in the rural areas and the market are situated in urban centres.
- Lack of market information hence farmers are exploited by middlemen.
- Price is the amount of money paid in exchange for goods or services.
- Price theory is concerned with the determination of price of any commodity.
- Price is determined where demand for and supply of any commodity are equal to each other.
- It is the quantity of any commodity which is purchased at any price within a given time.
- The law of demand states that quantity demanded changes inversely with the price.
- The curve slopes from left to right downwards.
- This means people buy more at lower prices and vice vers
Factors Affecting the Demand of a Commodity
- Income of the consumer.
- New inventions.
- Taste and preference of the individual.
- Price of the substitute commodities.
- Price expectations.
- Culture and social values of the consumers.
- Price of commodities having joint demand for example tractors and diesel.
Elasticity of Demand
- It is the responsiveness of demand to a change in price.
- Elasticity of demand = Percentage change in quantity demanded
Percentage change in price
Types of Elasticity of Demand
- Elastic demand is one where the ratio is more than 1.
- Unitary elasticity is one where the ratio is equal to 1.
- Inelastic demand is one where the ratio is less than 1.
- Supply is the quantity of any commodity which is offered for sale at any price at a given time.
- The law of supply states that when price rises, quantity supplied increases and when price falls quantity supplied decreases (other factors held constant).
- The curve rises from left to right upwards.
- This means that people are willing to offer more for sale at higher prices.
Factors Affecting Supply of a Commodity
- Number of sellers
- Price of substitute commodities.
- New technology.
- Price expectation.
- Peace and security.
- Weather conditions.
- Policy of the government.
- Cost of production of the commodities.
Elasticity of Supply
This refers to the rate at which quantity supplied changes due to a change in price level.
. . Percentage change in quantity supplied
Elasticity of Supply= Percentage change in Price
Type of Elasticity of Supply
- Elastic supply one where the ratio is more than 1.
- Unitary elasticity of supply is one where the ratio is equal to 1.
- In elastic supply is one where the ratio is less than 1.
- One of the problems of agricultural produce is that supply does not readily adjust to price changes.
- Is the price at which demand and supply are equal.
- That means whatever is offered for sale at the market is bought.
- In the graph below, the quantity supplied and demanded are equal at a price of Shs.300 and quantity of 80kg.
- At this point the price is higher than shs.300 then the supply will be greater than demand and there will be surplus hence price will fall.
- If, on the other hand, the price is less than shs.300 demand will be greater than supply hence shortage and rise in price.
- Agricultural organizations are agencies which, through their activities, promote agricultural development.
- These organizations are co-operatives and statutory boards.
- A co-operative is an organisation of people with a common aim of pooling their resources to achieve their objecti
Functions of Co-operatives
A co-operative society carries out the following functions:
- Collecting and assembling members’ produce.
- Processing the farm produce after collecti
- Transportation of members’ produce to market poi
- Negotiation of fair prices with the purchasing agencies for the members’ produc
- Purchase and distribution to members of farm inputs.
- Storage of members’ produce before transmission to market points.
- Provision of credit facilities to members on easy terms.
- Training and education of members on improved farming techniques.
- Offering farm machinery services to their members on hire terms for farm operati
- Co-operatives may invest in other viable ventures and the profits realised are shared among members in form of dividends or bonu
Formation and Structure of Co-operatives
The formation of a co–operative takes the following stages:
- Individuals with common interest collect together to form a primary co- operative society
- At least ten (10) members qualify for registration.
- Each primary co-operative society elect their office bearers consisting of chairman, secretary and treasu
- Several primary co-operative societies are usually amalgamated to form a district co-operative union.
- Tertiary co-operative unions are nationwide organizations to which the secondary co-operative unions are affiliate
- Examples are Kenya Planters Co-operative Union, Kenya Farmers Union, Kenya Co-operative Creameries, Co-operative Bank of Kenya, etc.
- Apex organization This is represented in Kenya by Kenya National Federation of Co-
operatives which is an affiliate of the International Co-operative Alliance.
Problems Facing Co-operatives
Co–operatives encounter the following problems in their operations:
- Managerial problems arising from:
- Financial mismanagement due to poor accounting.
- Corruption and misappropriation of cooperative resources by the personnel in the syste
- Lack of advisory services on technical operations.
- Inability to meet the set obligations of providing credit facilities due to malpractic
- The nature of agricultural products and associated problems.
- Bulkiness hence difficulties in transportation and storage.
- Perishability of produce hence difficult to sustain quality.
- Inadequate capital to invest in the cooperative undertakings.
- Transport problems due to poor roads.
- This hampers the produce getting to the market points in ti
- A statutory board is an organization established by an Act of Parliament and charged with the running or managing of a certain industry within the government s
- Some of the statutory boards are charged with the marketing of certain farm produce and are thus called marketing boards.
- Examples are the Coffee Board, Pyrethrum Board, Cotton Seed and Lint Marketing Board, Tea Boards, National Cereals and Produce Board, Kenya Meat Commission, the Dairy Board of Kenya and others.
- Their marketing functions are to look for market and better prices.
- These are research centres which among other things, carry out research and trials on:
- Development of new varieties and cultivars of crops.
- Breeding disease and pest resistant varieties of crops and types of animals.
- Adaptations of crop and livestock species to ecological conditions of certain areas.
- Use of fertilizers and pesticides on crops in specific areas.
- Development of early maturing and high yielding species.
- Soil testing and crop analysis. Advisory services of agro-economic aspects.
Kenya National Farmers’ Union negotiates for:
- Reasonable and affordable prices of farm inputs.
- Better prices for farm produce.
- Better credit facilities.
- Better control of diseases and pest.
Agricultural Society of Kenya
- Organizes agricultural shows in the country.
- Encourages improvement of livestock through exhibitions and educating farmers
- Organizes the running of young farmers’ clubs.
- Organizes and finances the ploughing contests during which farmers learn the modern techniques of seedbed preparation.
- Publish “Kenya Farmers” magazines.
Young Farmers and 4–K Clubs.
These are student organizations whose objectives are:
- To expose the young students and encourage them to appreciate agriculture as a profession in their career.
- To encourage the youth to develop leadership qualities through assignment of small farming projects.
- Organizing students exchange programmes with other club members both locally and abroad.
- To develop better farming skills through judging competitions, annual rallies and camps.
Agricultural Based Women Groups
- These are self-help groups whose objective is to uplift the economic status of their members by carrying out agricultural related activities.
Their success depends on the following factors:
- Commitment of their leaders.
- Motivation of the members.
- Sacrifice for each other.
- In Kenya land use is changing from extensive methods of farming to more productive and sustainable intensive methods.
- Agroforestry is a method of farming which has become increasingly important.
- This is the practice of integrating a variety of land use
- It combines tree growing, pasture and crop production practice on the same piece of land to improve the output of the land.
Forms of Agroforestry
- It is a combination of trees/shrubs and crops in agricultural production.
- It is a combination of growing tree/shrubs, pastoral and keeping of livestock.
- It is a combination of growing trees/shrubs, animals, pastures, and crops.
Importance of Agroforestry
- Environmental protection.
- Source of income.
- Afforestation for timber production.
- Maintenance of soil fertility.
- Aesthetic value.
- Labour saving in firewood collection.
- Source of food and feed.
- Source of fuel wood.
Important Trees and Shrubs for Particular Purposes
- Eucalyptus Spp;
- Bee forage,
- Fuel wood,
- Production of essential oils.
- Acacia Spp;
- Leaves and pods eaten by animals,
- Provision of shade.
- Cajanus cajan (pigeon peas);
- Proteinous feed for human,
- Used as fodder
- Croton megalocarpus(croton);
- Fuel wood timber for poles
- Handles for hand tools.
- Erythrina abyssinica (flame tree);
- Wood carvings,
- Bee forage,
- Nitrogen fixation
- Markhamia lutea (markhamia tree);
- Timber for construction,
- Soil protection,
- Bee forage.
- Grevillea robusta (silky oak.)
- Fuel wood,
- Bee forage,
- Soil protection,
- Wind breaker
- Sesbania sesban (sesbania);
- Nitrogen fixation,
- Fuel wood.
- Calliandra calothyrsus (calliandra);
- Fuel wood,
- Nitrogen fixation,
- Bee forage.
- Persea american (avocado) ;
- Fruit production,
- Fuel wood.
- Mangifera indica (mango);
- Fruit production,
- Shade trees,
- Wind break,
- Soil protection,
- Fuel wood.
Characteristics of Agroforestry Tree Species:
- Fast growth rate.
- Deep rooted.
- Nitrogen fixation ability.
- By-product production ability.
- Be multipurpose in nature.
- Should not possess competitive ability with main crop ..
- Have coppicing and lopping ability.
- Have appropriate canopy – should not shade others.
- Nutritious and palatable.
Trees and Shrubs to Avoid at Certain Sites and Reasons
- Eucalyptus Spp.-should not be planted near water sources because it would absorb the water.
- Eucalyptus Spp. -should not be planted on the arable land as the roots have allelophathic effects on other vegetation including crops.
- Tall trees should not be planted near farm buildings because they may fall and damaging the buildings, their roots will break the building stones gradually.
- Bushy trees or shrubs should not be near farm buildings as they may harbour predators.
- Tall trees planted with main crop of a lower canopy intercept the rainfall, affecting the growth of the main crop.
- Cypress trees have leaves which produce acidity in the soil preventing undergrowth beneath the tree.
- These trees should not be planted within the farm but at the periphery.
- Tree nurseries are structures used to raise tree seedlings until they are ready for transplanting.
- There are 2 main types:
Bare root nurseries:
These are also known as ‘Swaziland’ beds where the seedlings are raised directly into the soil.
- Cheap and less time consuming.
- Require less labour
- Occupy a small space.
- Many seedlings are raised in a small space.
- Transportation of seedlings is easy.
- Root damage when uprooting the seedlings.
- Difficult to transport.
- Lower survival rate after transplanting.
- The seedlings in this type of nursery are raised in containers such as pots, polythene bags or tubes and tins.
- Higher survival rate after transplanting.
- No root damage.
- Successful in arid areas.
- Labour intensive.
- Difficult to get containers.
- Sometimes it may be difficult to get the right type of soil to use in the containers.
Seed Collection and Preparation
Seeds should be collected from;
- Adaptable trees,
- High yielding,
- Resistant to pests /diseases.
- The mother plant should be identified first.
The following methods used to collect seeds.
- Shaking the tree.
- Gathering from under the tree.
- Lopping of the tree.
- Climbing on the trees.
- Hooking method.
- This done when seeds are collected from a fresh fruit, they should be soaked in water, then washed and dried.
- Cleaning and sorting: done to remove immature seeds, rotten seeds, broken or damaged seeds.
- Drying: Done by sun-drying or oven drying.
- Seed testing: this determines;
- Seed quality for percentage purity,
- Seed weight,
- Moisture content,
- Germination percentage.
- Seeds should be stored in dry containers at room temperature.
- Seed treatment: seeds are treated first to break the seed dormancy and ensure rapid germination;
- Hot water treatment: used to soften the seed coat to make it more permeable to water.
- Examples of seeds which require this treatment are leucaenia, calliandra and
- Mechanical breaking: done by nicking the seed coat with a knife for easy entrance of water for example seeds of croton
- Light burning: applied to the wattle tree seeds.
The following are the practices carried out in the nursery when the seedlings are growing:
- Aim is to reduce excessive evaporation,
- Moderates the soil temperature,
- When it decays it improves the soil structure,
- Reduces the impact of the raindrops.
- Done to reduce competition for growth factors by uprooting the weeds,
- Use a sharp pointed stick.
- Done by use of a watering can
- Done twice a day in the morning and in the evening.
- Pricking out:
- It is the removal of seedlings in an overcrowded area to another nursery bed,
- This allows the seedlings to grow strong and healthy.
- Root pruning:
- It is the cutting of the roots longer than the pots.
Root pruning is done for the following reasons;
- Make lifting easier
- Encourage fast establishment.
- Reduce damage to the seedlings.
- Encourage development of a short dense and strong rooting system.
- Done to reduce the intensity of sunlight .
- Dark conditions should be avoided.
- Pest and disease control:
- Use of appropriate chemicals,
- Sterilization of soil through heat treatment,
- Fencing to protect seedlings against animal damage.
- Hardening off:
- It is the practice of preparing seedlings to adapt to the ecological conditions prevailing in the seedbed.
- It involves gradual reduction of shade and watering 1-2weeks before transplanting.
- The practice of transferring seedlings from the nursery bed to the main field where they grow to maturity.
Procedure of Transplanting
- Holes are dug early before transplanting.
- Topsoil is mixed with compost manure.
- The seedlings are watered well a day before transplanting.
- The seedlings are removed from the nurseries carefully with a ball of soil for the bare root seedlings and roots trimmed for the containerized seedlings.
- The seedling is placed in the hole at the same height it was in the nursery.
- The container is removed carefully.
- The soil is returned into the hole and firmed around the seedling.
- The seedling is watered and mulched.
Care and Management of Trees
- From damage by animals such as goats and cattle by eating the leaves.
- It is done by fencing the fields or using small poles around each seedling with or without wire nettings, can be done for individual trees or an entire field.
- Pruning and trimming:
- Pruning is the removal of extra or unwanted parts of a plant.
- The unwanted part may be due to breakage, overcrowding, pests or disease attacks and over production.
- Pruning initiates growth of shoots and trains the tree to have the required shape.
- Regular cutting back of the trees is known as coppicing,
- It is done at the beginning of each cropping season to reduce competition for water, minerals, nutrients and sunlight with crops.
- The materials pruned or coppiced are used as fuel wood or for fodder crops.
- Grafting old trees:
- This is the practice of uniting two separate woody stems.
- The part with the rooting system is known as root stock (base)
- The part which is grafted onto the rootstock is called a scion which has buds that develop into the future plant.
- The ability of the scion and the rootstock to form a successful union is known as compatibility.
- Methods of grafting include whip or tongue grafting, side grafting and approach grafting.
- Alley Cropping/Hedgerow Intercropping:
- The growing of multipurpose trees and shrubs together with crops.
- Improve soil fertility through nitrogen fixation and organic matter.
- Provision of green manure.
- Used as fence and mark boundaries.
- Acts as windbreaks.
- Suppress weeds.
- Source of timber and fuel wood.
- Multi-storey cropping ;
- This is the growing together of trees of different heights.
- The system is based on crops which can tolerate shading.
- The trees and crops form different levels of canopy which look like storey.
- Increases water conservation for pastures.
- None of the crops or trees included will be shaded.
- Act as windbreak for crops.
- Creates suitable micro-climate in the area.
- Trees are used for timber, fuel wood and forage.
- Woodlots (farm forests)
- These are plots of land set aside for trees only.
- They are established in the hilly and less productive parts of the farm.
- Fast growing tree species such as Eucalyptus spp. should be grown.
Sites for Agroforestry:
- Farm boundaries – provide live fences.
- River banks – protect water catchment areas.
- Homesteads – provision of shade and windbreak
- Terraces – for soil conservation.
- Steep slopes – as contour hedges to encourage water seepage.
Tree Harvesting Methods
- This is the extensive cutting back of the crown of the tree about 2-3 meters above the ground level to harvest all the side branches.
- It stimulates the development of a new crown and branches.
- Cutting the main stem of the tree completely at a height of 10 – 50 cm above the ground.
- The tree should be cut in a slanting angle.
- Lopping or side pruning ;
- The removal of selected branches of the tree
- Done to produce fuel wood and fodder.
- Shaking of the tree ;
- This is a method of harvesting pods and seeds from trees without cutting the tree.
- Cutting back;
- The tree is cut from the base to allow new growth as done in coffee when changing the cycle.
- The removal of some of the trees growing in lines to give the remaining trees enough space to grow.