Page 160 - Agriculture_Form_3

Agriculture for Secondary Schools

hours after the heat starts. AI allows farmers to use semen from high-quality bulls.
It also helps to reduce disease spread. However, AI requires skill, correct timing,
and clean tools. Figure 9.5 illustrates the artificial insemination procedure.
Guiding arm Large intestine Uterus
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Bladder
Inseminating rod Ovaries
Figure 9.5: Artificial insemination procedure

Breeding methods and herd improvement
Farmers improve their dairy herds by choosing the best animals to breed. One way
is to mate local cows with improved bulls, which is called crossbreeding. This
helps increase milk yield and keeps animals more adaptive to local conditions.
Another way is upgrading, where improved bulls are used over many generations.
This slowly changes the herd and makes it more productive.

The same bull should not be used with its daughters or sisters to avoid genetic
problems. This act is called inbreeding and can lead to weak calves. Farmers
should bring in new bulls or use AI to avoid inbreeding. Poor-performing or
infertile animals should be culled to save feed and space. This helps to improve
the herd and farm income.

Management of the breeding bull
A breeding bull needs special care to keep it productive. It must be housed in a
strong, safe pen away from other animals. Bulls must be handled carefully and
may need a nose ring for control (refer to Figure 9.6). A nose ring may be placed
as the bull reaches 15 to 18 months of age, just before it begins mating. This is
done to make handling easier and safer, but the ring should never be used roughly,
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