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THEME 2.0: LIVESTOCK PRODUCTION
IMPROVEMENT OF LIVESTOCK BREEDS
Introduction: The goal for keeping animals is to produce animal products which are sufficient and qualities enough.
∙ So as to achieve, this livestock keepers, must have good quality animals, feeding them well and keep them healthy.
Livestock Improvement
The productivity of farm animals is set by INHERITANCE i.e. passing of genes from parents to off springs however the environment determines how much the inheritance potential is going to be reached. So livestock improvement is therefore the program that set out to improve the inheritance of the environment in which they are kept.
Concept of inheritance
Inheritance deals with the mechanism by which characteristics of parents are passed to the off springs. The mechanism of inheritance resides in the sex cells (gametes) in both males and females which contain CHROMOSOMES carrying units of inheritance called genes.
∙ Chromosomes occur in pairs in the nucleus the number of chromosomes e.g. Cattle -30, Sheep -27, Pig -19, Chicken -39
∙ The members of each pair are called HOMOLOGOUS CHROMOSOMES.
∙ Genes are located in specific units of chromosomes called Locus.
∙ The genes located at the some loci of chromosomes pair are alleles.
∙ If they have the same effect are called homozygous.
∙ If they have different effects (antagonistic) are called heterozygous.
∙ Sex cells undergo cell division whereby the cell divides to form daughter cells with half number of chromosomes from parent cells.
∙ So the male and female gametes when fused together during fertilization the chromosomes number is restored. Off springs formed receives genes from both.
The concept of heredity
This is a numerical measure of the portion of total variation among animals in particular characteristics that is caused by genes the animal posses. It is expressed in%
e.g. the heredity of certain character is 50% means all the differences between the animals in the herd as for that character is concerned will be 50% genetic and 50% environmental.
Significance of knowing hereditable of a character
i. Help the breeder to be able to select the best breeding method.
ii. Help to estimate the expected progress towards environment of animals.
Table to show heritability of dairy cattle
Character | Heritability |
Milk production | 25% |
Dairyconformation | 20% |
Butter fat | 60% |
Matureweight | 60% |
THE CONCEPT OF BREEDING
Breeding: Is a way of changing the genetic constitution of animals for future generation.
Objectives:
i. To increase yield of meat, milk, eggs etc
ii. To improve disease resistivity.
iii. To improve resistance to dry/ hot climate.
Methods used to improve Genetic makeup of an animal
i. Selection
ii. Making system (out breeding and in breeding)
I. Selection:
Is the process of allowing certain animals to be parents of the future generation
∙ Animals with undesirable characteristics are sold while those with desirable characteristics are retained.
Advantages
Selection increases the frequency of the desirable genes and decreases the frequency of undesirable.
Disadvantages
Disadvantages
If desirable genes are lacking in the herd selection will not introduce them so it becomes ineffective tool for livestock improvement.
NB: Selection requires skills, proper keeping of records of the performance of animals and monitoring of the performance of its progeny.
II. Mating system
It is a system where the breeder decides which sire (male) is to mate with bome (female). This is done after the selection of the breeding herd.
Types of Malting
a) Out breeding
b) In breeding
OUT BREEDING
Is a system based on unrelated sire and bomas.
Objective of Outbreak
∙ To introduce new genes into the herd e.g. Zebu cattle cracks genes for high milk yield but Friesian have this gene, So by mating a Friesian bull to a Zebu cow the heifer are raised from the union will inheritance the high milk yield from the Friesian sire genes.
∙ To obtain a hybrid vigor i.e. when un related sire and dame are matted the offspring grows faster than the parents.
IN BREEDING
Is a system based on mating related sires and dam
Objectives of In breeding
∙ To make sire and dame of the same herd to selectively, transmittable characteristics.
Advantages:
i. Increase the number of homozygous pairs of genes for characteristics.
ii. Increase uniformity of the herd i.e. pure line is obtained.
Mating systems methods
i. Natural system
ii. Artificial Insemination
I. NATURAL SYSTEM
Takes place by allowing mating i.e. copulation by penis. It is done when the female shows signs of heat.
II. ARTIFICIAL INSEMINATION
∙ It is done by trained inseminator who introduces selected semen to the reproductive duct of the dame using special instrument.
∙ The semen is obtained from the sire using artificial vagina and teaser animal and stored in a deep frozen tube.
∙ The semen can be diluted and used to inseminate 50-200 dames from a single male sire.
Advantages
∙ It reduces chances of spreading viral diseases which might be spread by the male.
∙ Semen from high quality sire can be made available at a low price.
∙ The transportation and distribution of semen is easy since they are stored in a small container while in natural system involving movement of the sire.
Disadvantages
∙ Require skills.
∙ If not done well semen from heavy breeds may be introduced to light breeds hence bringing problems during birth.
Livestock breeding stations in Tanzania
i. Kitulo- Iringa
ii. Uyole – Mbeya
iii. Mpwapwa – Dodoma
iv. Tengeru – Arusha
v. Maruku – Bukoba (Kagera)
vi. Mabuki – Mwanza
Principles of good livestock breeding
i. Selection of desirable sires and mates
ii. Care of sires and dames before service
.
.
iii. Breeding at proper age.
iv. Servicing (coition) at the right time.
v. Appropriate breeding system.
vi. Care of pregnant animals up to parturition time.
vii. Care of young animals
viii. Castration of un required male animals.
ix. Culling.
FISHERIES
This refers to the process of producing and rearing fish- fish farming.
∙ This is done by keeping fish in aquarium or tanks or by breeding fish and then release them into dams, ponds and rivers.
∙ Any fish reared must be adaptable to the climatic condition of the area.
∙ It is advisable to construct a fish pond on a level ground and near a source of water e.g. river, steam.
∙ A fishpond should be able to hold water throughout the year.
∙ Avoid slope places and porous soils e.g. sand soil is not suitable while clay is the best.
∙ It should neither be too shallow nor too small at least 1.5m deep 20-25cm wide.
∙ Walls of the proud should be raised and grass should be grown on the walls to make the soils firm.
∙ Enough nutrients should be available in the pond water for the growth of aquatic plants.
∙ The pond should be protected from pollutants.
A f
ish pond should have
A f
ish pond should have
i. Inlet where water enters the pond.
ii. Spill way; which allows overflowing water to flow back into the river.
iii. Outlet pipe; At the bottom of the pond for draining water.
iv. Fence; for keeping away thieves, animals and other creatures from polluting the pond.
Significance of fish farming in Tanzania
∙ Provide high quality protein.
∙ Provide employment and recreation.
∙ Source of income.
∙ Source of foreign exchange.
Main types of fishers
i. Marine fisheries.
ii. Fresh water fisheries e.g. Pangani and Rufiji estuaries are also sites for prawns.
Common species/ Fish types in East Africa ponds
∙ Trech, back base, cat fish, tilapia and trout etc.
∙ Catfish is well adapted to fresh water.
∙ Tillapia is the most preferred by e.g. T. sparrmani, T. galilae, T. heudeloti, T.esculanta, T. leucostica, T. andersomii etc.
Advantages of Tillapia
∙ Local consumers are accuctomed to their taste.
∙ The climate is good to them i.e. 20-30c with an exception of T. sparrmani can stay even at 8c
∙ Young fish for stocking are readily available.
∙ They are either omnivorous or herbivorous hence easy to feed.
∙ They breed and grow fast.
∙ They are affected by few parasites.
Characteristics of Herbivorous Tillapia
∙ They eat plants.
∙ Have high production potential examples Tillapia tholon, Tillapia zillii
Characteristics of Omnivorous Tillapia
∙ They eat both plants and animals like snails, mosquito larva and worms.
∙ They keep their eggs in mouth until they hatch i.e. mouth incubating practices, examples; T. macroch, T. mossambia, T. rulotica, T. nigra.
FEEDING
∙ They sh
ould be fed daily, may be fed with commercial feed i.e. pellets, rich bran, ground nut cake, maize bran.
ould be fed daily, may be fed with commercial feed i.e. pellets, rich bran, ground nut cake, maize bran.
∙ Don’t overfeed the fish as it can reduce the supply of oxygen, feed according to the pond size.
HARVESTING
∙ Is done when the fish are matured e.g. Tillapia 8 months are ready with a length of 20-30cm long.
Methods:
i. Hook and line methods
ii. Catching nets.
iii. By draining the entire water pond.
iv. By use of cast with appropriate sized mesh.
Diseases and Parasites of fish
∙ Most of the fish die because of pollutants which causes diseases as such when they decompose they infect the pond with diseases and thus spreading diseases.
∙ Certain birds hatch on ponds and they may spread diseases.
Care and Maintenance of the ponds
∙ Should be fertilized twice a week.
∙ Water lever should be checked.
∙ Grasses and weeds around fish pond should be slashed.
∙ Repair the wall if there is any leakage.
MARKETING
∙ Local and town markets.
∙ Some are exported.
STORAGE
∙ Stored in frozen state.
∙ Stored when dry under the sun after removal of offal and scales.
∙ Salting and drying.
∙ Smoking.
