Fall-calving cow herds will soon be entering the breeding season. By now the bulls should have passed a breeding soundness exam and have been found to be free of Trichomaniasis. If this has not been done, visit with your large animal veterinarian today. Breeding soundness exams, however, do not detect low libido bulls.
A good manager keeps an eye on his bulls during the breeding season to make sure that they are getting the cows bred. Occasionally a bull that has passed a breeding soundness exam may have difficulty serving cows in heat, especially after heavy service. Inability to complete normal service and low fertility are more prevalent and therefore more detrimental, than is low libido (failure to seek out and detect cows in heat) to calf crop percent. Such problems can best be detected by observing bulls while they work. Therefore producers should (if at all possible) watch bulls breed cows during the first part of each breeding season. If problems are apparent, the bull can be replaced while salvaging the remainder of the breeding season and next year’s calf crop. Likewise a small proportion of bulls can wear out from heavy service and lose interest. These, too, will need to be replaced. The greater the number of cows allotted to each bull in the breeding pasture the more critical it is that every bull be ready to work every day of the breeding season.
Injuries to bulls during the breeding season are relatively common. When a bull becomes lame or incapable of breeding, because of an injury to his reproductive tract, he needs to be removed from the breeding pasture and replaced with another bull.