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Selection and breeding - Agriculture Form 3

The Secondary Agriculture course aims to:

1. develop an understanding of agriculture and its importance to the family and the nation

2. promote interest in agriculture as an industry and create awareness of opportunities existing in agriculture and related sectors.

3. demonstrate that farming is a dignified and profitable occupation

4. enhance skills needed in carrying out agricultural practices

5. provide a background for further studies in agriculture

6. develop self-reliance, resourcefulness and problem solving abilities in agriculture

7. develop occupational outlook in agriculture

8. enable schools to take an active part in national development through agricultural activities

9. create awareness of the role of agriculture in industrial and technological

10. enhance understanding of the role of technology and industrialization in
agricultural development

11. promote agricultural activities which enhance environmental conservation

12. promote consciousness of health promoting activities in agricultural production.

Welcome to form three agriculture digital content.

Agriculture is an important subject in our day to day life. In form one and two you were introduced to both crop and livestock practices. In form three you will continue broadening the content scope using the following topics:-

The agriculture digital content is dynamic and interactive, to enhance learning in more enjoyable manner. You will also have the opportunity to learn new skills as you navigate through form three agriculture digital content and practice answering examination questions as a preparation for the subject evaluation. Practical activities are also suggested to link theory and practice. Welcome and enjoy form three agriculture digital content.

Selection and breeding

1.Learners to visit a nearby farm and practice selection of suitable breeding stock.this can be done by examining many animals of each species in a farm and to select suitable ones with such characteristics:

  • Records of performance of parents.
  • Body conformation.
  • Level of performance.
  • Health status.
  • Temperament
  • Age

2. Teacher to lead learners in visiting a nearby slaughter house to study the reproductive organs of cattle and poultry.

3. Learners to visit a livestock farm to study the following:

    Make observations on signs of heat in cows and pigs.

    Observe natural mating in cattle.

    Observe how artificial insemination carriedout in cows.

    Observe signs of parturition in sheep and sheep.

Background information to Selection and breeding

In form one you learned about importance of livestock and the various species of livestock and breeds. In form two you studied nutritional requirements of livestock and classified various feedstuffs into roughages and concentrates. You also studied the digestive systems of ruminants and non ruminants.Finally you computed livestock rations using the Pearsons square. In this topic you shall learn the reproductive systems of different farm animals before studying the various aspect of livestock breeding.

Selection and Breeding

A dominant gene - is one that is expressed in an offspring. A recessive gene - is a gene that is suppressed by another one. Cross breeding -mating of animals of two different pure breeds. In breeding-mating of animals that are related. Line breeding -mating of distantly related animals with a common ancestor Out crossing - mating of animals of the same breed Up grading- mating of a pure breed sire with a low grade cow. Hybrid vigour -increased performance resulting from crossing two superior animals Epitasis- the combination of genes which individually could have been undesirable. Mass selection -choosing animals for breeding on the basis of their own performance.

Topic Objectives

By the end of this topic you be able to:

  • describe reproduction and reproductive systems.
  • select breeding stock.
  • describe breeding systems.
  • identify signs of heat in livestock.
  • describe methods of serving livestock.

Selection and breeding

Before selecting the breeding stock it is good to have the knowledge of reproduction system of the animal.Breeding is the process of mating selected male and female animals to produce offspring with required traits or characteristics.

Click the play button to see the video on selection and breeding

Selecting dairy cattle for breeding

Reproduction process

Reproduction is the process by which offspring are produced.The process of reproduction takes place in the organs shown below

Click the play button to see the video on selection of breeding stock based on the best bulls.

Reproductive system of a bull

The male reproductive organs in the various mammalian species are similar in form and function. The testes or testicles in the male are the primary sex organs and are held in a sac called the scrotum. They produce spermatozoa and the male hormone, testosterone.Reproductive system of a bull consists of:Testes, Epididymis, Sperm ducts, Accessory glands and Penis.

Reproductive system of a cow

Reproduction in poultry

Reproduction in poultry is different from other farm animals e.g. the cock has no penis. Instead, it has a small opening near the vent through which sperms are released. It has testes within its body.Reproductive system of a hen consists of the following:

Reproductive system

Reproductive system consists of all those organs involved in reproduction. In this topic you will learn the reproductive systems of both male and female farm animals:

Reproductive System in Poultry

Reproduction in poultry is different from other farm animals e.g. the cock has no penis. Instead, it has a small opening near the vent through which sperms are released. It has testes within its body.

Mating in livestock

Oestrous is the time the female has ovulated or is about to ovulate and is "receptive"to the male.

Cow on heat shows the following signs of heat:

  • Mounting others and when mounted it stands still.
  • Bellowing
  • Frequent urination
  • Restlessness.
  • Slight drop in body temperature
  • Swelling and reddening of the vulva
  • Clear or slimmy mucus discharge from the vulva

Signs of heat on a Sow

Signs of heat on a doe


(A bull mating a cow)

Methods of service in livestock

There are three methods of service in livestock. Namely;

  • Natural mating,
  • Artificial insemination
  • Embryo transplant

Semen harvesting

Apart from massage method and electrical stimulation, artificial vagina is used to collect semen from breeding bulls. Artificial vagina is made up of the following parts;
Warm water in a rubber casing and Collecting cup

Artificial insemination

Click the play button to see the video

Embryo transplant

This is a technology where ova (eggs) are harvested from high quality female animals (donors) and fertilized in the test tubes and the embryos are then artificially implanted into foster mothers (recipients).

Pregnancy Management

Click the play button to see the video

Signs of parturition in cattle

Parturition, or labor, is the act of giving birth to young one. It marks the termination of pregnancy.

A cow that is about to calf down will show the following signs;

  • Restlessness,
  • Enlarged vulva,
  • Appearance of water bag,
  • Full and distended udder,
  • Thick milky fluid from the teats,
  • Slackening of the pelvic muscles.


Importance and types of fences.

A fence is a structure that encloses a designated area and form a physical barrier for animals and humans. The following are importance of fences:-

  • Marking of boundaries
  • Keeping intruders and wild animals outside the farm
  • Enable farmers to isolate sick animals from the rest of the herd
  • Makes rotational grazing possible through paddocking
  • Enable farmers to control breeding
  • Enable farmers to practice mixed farming
  • Acts as wind breaks

Types of fences

There are many types of fences that can be established in the farm. A farmer may plant hedges or use other non-living materials for fencing, for example, wood, wires and posts among others. The process of fencing starts with clearing the area where the fence line will pass. Marks on points where holes are to be dug are then made. The posts are then placed in the holes in an upright position and concrete mixture is added in the holes or soil and stones which should be rammed to firm the base. The struts are then fixed on the end posts and the wire is nailed onto the posts using fencing staples while stretching it using a wire strainer the droppers should then be fixed to prevent sagging of the wire.


Wire fence

Stone fence

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