Breeding of farm animals. Process of mating selected males and females to produce offspring with the desired characteristics. Breeding is a natural or artificial way of reproducing farm animals for grater yield, an animal selection practice to encourage chosen qualities. a process where some animals were chosen because of their special qualities. these qualities can be because of pure strength for the sole purpose of farm work like tillage practices
TYPES OF BREEDING IN FARM ANIMALS
- Cross breeding–=== Cross breeding is the act of mating of animals from two breed of same species. Normally, breeds are chosen that have complementary traits that will enhance the offspring for economic purposes and business
- selective breeding== an animal selection practice to encourage chosen qualities. a process where some animals were chosen because of their special qualities. these qualities can be because of pure strength for the sole purpose of farm work like tillage practices
- selective smart breeding—=== plant selection practice to encourage chosen qualities. this type breeding takes place amongst plants only mostly if the plant species that is intended for use a special resistance capability for resisting diseases
- inter-breeding===the act of mixing different species or varieties of animals or plants and thus to produce hybrids. this requires high scientific foundation
Reasons for breeding of animals
The following reasons are some the triggers for breeding purposes. Breeding can be carried out in order to improve the inherited potential of the animal.
To improve production by introducing new genes.
This process overcome production problems created by the environment.
in order to satisfy consumers taste.
a farmer may decide to carry out specific purposes just For economic reasons e.g fast growth rate to reach the market early.
TERMS USED IN BREEDING
Inheritance; Genetic transmission of characteristics from parents to offspring.
The mechanism of inheritance is carried by the sex cells (gametes) and is controlled by genes found in the chromosomes.
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 of the body cells. They are always constant in number.
Dominant and Recessive Characteristics
A dominant gene is one that suppresses the other. It produces a dominant characteristic.
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A recessive gene is one that is suppressed by the other. It produces a recessive characteristics
What is Hybrid and Hybrid Vigor breeding?
A hybrid is an animal which is the product of crossing animals of two different breeds. It has both a dominant and recessive characters. A superior hybrid has 75% dominance and 25% recessive.
Hybrid vigour or heterosis is increased vigour and performance resulting from crossing two superior breeds. When two superior breeds e.g Pedigree friesian and Jersey breeds are mate the resultant offspring have both the character of high milk yield and high butterfat content. Thus it is said the offspring have hybrid figure which is an increased perfomance and figure than both the two parents.
what is Epitasis in animal breeding
This is the masking of the effect of one gene (recessive gene) by another gene(dominant) which is non-allelic, that is situated on different locus.
This is aimed at preventing the recessive gene from being expressed.
BREEDING SYSTEMS
They are categorized into two namely; Inbreeding and Out-breeding
1. Inbreeding
Mating of animals which are related i.e have certain alleles of genes in common.
Reasons:
To increase genetic uniformity in a herd.
To increase phenotypic uniformity.
To get proven sires.
To fix required characteristics when developing a new breed.
used in animal of higher prepotency (stud Bulls)
LIMITATIONS TO BREEDING
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, halfbrothers/sisters, grand daughters and grand sires.
2. WHAT IS OUTBREEDING
Mating of animals which are not related.
Reasons:
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.
Limitations
Lack of uniformity in animals that result from out-breeding.
Desirable characteristics may be lost due to variation.
Systems of Outbreeding
i). Cross-breeding
Mating of animals from two different pure breeds to attain hybrid viguor or heterosis such as higher production rate, higher production rate, high growth, disease resistance and heat tolerance.
II). OUT-CROSSING
Mating of unrelated animals from the same breed for example fresian cow in kenya with Seminal fluid of fresian bull from Britain.
iii) Upgrading/Grading up/Back-crossing
Mating where the female of a cow grade (locals) is mated with a pure breed sire. The resultant animal is referred to as a high grade.
If the same sire mates with filial generation (F1-6) of its heifers, it will attain a pure breed character. With Artificial insemination (A.I) the systemis used widely to improve the local cattle for better milk production
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.
Heat Signs
Restlessness.
Mounting on others and when mounted on she stands still. Rise in body temperature.
Drop in milk production in lactating cows. the female private part swells and becomes reddish.
Clear or slimy mucus from the opening
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
Restlessness.
Frequent urination.
Swelling and reddening of the
Clear or slimy discharge from the
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
Restlessness.
Frequent urination.
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
Natural Mating
Advantages:
It is more accurate.
It is less laborious.
Useful when heat signs of females cannot be easily detected.
Disadvantages
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.
ARTIFICIAL INSEMINATION IN BREEDING
Introduction of semen into the female reproductive tract by artificial means.
Advantages
There is economical use of seminal fluid.
It controls transmission of breeding diseases.
Sires that are unable to serve cows due to heavy weight or injury can produce seminal fluid 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.
DISADVANTAGES OF ARTIFICIAL INSEMINATION BREEDING
Harmful characteristics can be spread quickly by one bull to the offspring.
It requires skilled labour.
Low chance of conception due to death of seminal fluid during storage.
It is laborious:
Embryo Transplant
It is the implantation of an embryo (fertilized ova) from a high quality female (donor) in the uterus of a low grade female (recipient).
Advantages
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. Offspring of a superior female can spread quickly in an area.
Disadvantages
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
Restlessness
Clear mucus discharge from the outer opening.
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
Restlessness.
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
Restlessness.
The udder distends.
