Bull Management Before the Breeding Season
To better understand bull breeding management, divided the year into three seasons:
- Pre-breeding or conditioning
- Breeding season
- Post-breeding season or rest and recuperation
Libido testing, like most tests of biological systems, requires the use of considerable judgment. Generally, bulls that score 10 very quickly can be removed from the pen before the completion of the 10-minute test. If some bulls seem intimidated by other bulls and/or observers, the bull can be left in with females for 20 minutes. Try to test bulls of similar ages in the same groups. Libido testing should be combined with the other aspects of breeding soundness evaluation.
Bull Management and Care in the Western U.S. During and After the Breeding Season
Consider that a bull’s contribution to the calf crop is 30 times greater than each cow within the breeding herd, assuming 30 cows per bull with a 100 percent calf crop. To exert a positive influence on the herd, it is necessary that proper bull power be maintained. Young bulls control such venereal diseases as trichomoniasis. Proper nutrition is essential to maintain fertile active bulls. Pasture size, forage, and water availability are factors to consider particularly during the breeding season.
Purchasing and Managing Young Bulls
Younger bulls usually cost less and have less invested in their development. Young bulls are also the best to control trichomoniasis. Older bulls often carry the organism. Replacing them with younger bulls removes that source of the disease. The breeding ability of bulls usually is at its highest between 1 1/2 and 2 1/2 years of age and declines after 5 or 6 years of age. Proper development of young bulls after purchase can have a positive impact on herd fertility.
Reproductive Tract Anatomy and Physiology of the Bull
Normal functioning of the male in reproduction is largely controlled by hormones. Bulls are selected for their genetic potential to improve the cowherd. It is economically important that all bulls are fertile. A breeding soundness examination performed yearly on each bull is the best way to predict that the producer will get his money’s worth from his bull battery. The bull needs to be able to see, eat, smell, and move around to successfully breed his share of cows. Any factor that lowers the efficiency of these activities will have a negative effect on the bull’s breeding ability. Breeding soundness evaluation is a practical method to eliminate bulls with less than satisfactory breeding potential. This evaluation should be conducted on every bull 30 to 60 days before each breeding season to allow time to replace questionable or unsatisfactory bulls.