There are several important things to consider when selecting males for breeding
- A healthy and good quality buck (he goat).
- Strong and should have a well-developed body frame.
- It must be of productive breed (viability)
- It must have normal sexual organs and well developed testicles.
- The buck must be selected from does that produce a high volume of milk and are prolific.
- Control mating i.e. Limit the number of does per male (the recommended ratio is 1male for 35 does depending with the age of the male)
- The Buck must be free of any physical defects e.g. undershot jaws, overshot jaws
- It should have a strong masculine head and neck. It should seek out females on heat and mate them. If it’s shy and timid it should be culled.
- Badly worn teeth indicate old age. Males with split, missing or worn teeth should not be selected for breeding as they are physically unable to browse or graze properly.
- Legs should be checked for deformities and hooves trimmed.
- Select males with larger testes since this is directly related to viability
Selecting a Replacement Buck
- A healthy and well developed male for mating should be identified by the second month of birth. It should be used for breeding when it is 11 months old. Depending on the dairy breed the buck should weigh 10-15 kg at six months and about 20-25 kg at 11-12 months of age.
- At the beginning the use of young buck should be limited to 10-15 does per male, but at the end of the second year the number of does can be increased and maintained at 35-40 does per buck. One active buck can serve up to 20-25 females per season
- Bucks should be properly utilized to control their temperament. Under-utilized bucks tend to be vicious and very destructive. At least 3 services per week will keep the buck busy.
- Polled goats may result in hermaphrodite kid(s).
- Replace bucks after 18-24 months of active service to prevent inbreeding.
Selection of the breeding doe
The productivity of a flock depends on the good quality of the mother. Select does with high milk production and high fertility rate. It is also important to consider the history of the dam before it is selected
- The doe must be well built and healthy. A female should not be mated unless it’s physically fit. Thin females will not come into heat, will be become pregnant and abort, and reabsorb the fetus at early stage. Those which are mated and carry their kid will be unable to rear it satisfactorily.
- Legs should be checked for deformities and hooves trimmed. Good strong legs are essential from breeding doe. Weak bent hind legs are highly heritable factor and females with this should not be selected for breeding.
- It should produce kids every 8-10 months
- It should produce twins frequently
- It should produce enough milk to rear the twins and for the household consumption
- The udder should be soft to touch with two functional teats. Any hardiness indicates the female has had a problem e.g. mastitis. Long pendulous udder is highly heritable and females with this should not be used for breeding. Big udder is liable to tearing by thorns and kids have difficult in suckling them. It also predisposes the doe to mastitis.
- Badly worn teeth indicate old age. Females with split, missing or worn teeth should not be selected for breeding as they are physically unable to browse or graze properly.
- Any female with physical deformities (e.g. bad feet, hard udders, blind eyes ) should not be selected for breeding
There are several breeding systems that can be used in breeding of dairy goats depending on the environment and purpose.
- Heritability factors (Inheritable traits)
Many of the qualities in goats are highly heritable and knowledge of those which can be passed on from parents to the progeny is useful to the breeder who wishes to improve his stock
- Inbreeding – This is mating of closely related individuals without the introduction of new animals from outside. If the process continues animals with undesirable characteristics are likely to appear e.g. physical deformities, sterility and reduced body sizes.
- Line breeding – This is a mild form of inbreeding designed to concentrate the genes of a specific ancestor
- Crossbreeding – This is system where two different parent breeds are mated. The first generation crosses are intermediate to the parent breeds. The offspring are superior to the parental breed in some cases (hybrid vigour). The offspring’s displays increase in size better live-weight gains fertility and viability
- Backcrossing – This involves crossbred offspring’s being bred to one of the parents
- Upgrading – Foundation refers to an F1 (first generation) at 50%, Intermediate (second generation) is at 75%, an appendix (third generation) is at 87.5% and pedigree (Fourth generation) is at 92.5%. The percentage represent the proportion of the exotic blood in the resultant cross (breed)
Signs of a doe on heat
For a doe to come on heat it should be nutritively fed under proper alongside appropriate supplementary feeding of concentrates and mineral licks. A doe on heat will show the following signs
- The vulva appears swollen and reddened
- loosing of appetite and restlessness
- Frequent urination
- Bleating and nervousness
- Wagging of the tail
- Slight mucus discharge from the vulva
The presence of a buck has been shown to induce heat in a doe that could have been problematic in detection of heat. Heat can also be induced by rubbing a piece of cloth around the base of the buck’s horn and then taking to the doe.
For successful fertilization to occur the doe has to feed well and kept in good shed. She must be in good health. To become pregnant the doe and the buck must mate. A doe noticed to be on heat should be brought to the buck and remain with it for a period of not less than 36 hours for effective mating to take place. If mating is successful, heat signs will not appear and pregnancy will be assumed to have occurred.
The gestation period lasts for 5 months. If mating has not been successful heat signs will occur and a second mating service will be necessary. Repeated signs of heat even when the doe has been mated could be due to a problem with either the buck or the doe and therefore the doe and the buck should be examined by a vet. The farmer is advised to make timely observation of the onset of the heat so that mating is allowed at the correct time for effective conception
Artificial Insemination services for Dairy Goats are available at the Central Artificial Insemination Station (Kabete). The semen available is for German Alpine sold at Ksh500 per straw.