For our purposes, we prioritize this process before the bull sale in order to identify individuals who are unsatisfactory for successfully completing a breeding season-this involves a lot more than simply determining sterility.
First, an overall physical assessment for soundness is made. Then, testicles are measured as a correlative to fertility and maturity and examined for consistency, uniformity and the presence of any abnormalities. We also really want to make sure there are two . . .
Next, the penis is examined for a normal extension, for warts (which are prone to vascular bleeding and interfere with fertility) and for the presence of a persistent frenulum or “tie” which occasionally results when the penis and prepuce did not separate completely. This presents a physical impediment to extension and must be surgically addressed. Finally, a semen sample is examined for motility (movement and activity) and morphology (form, structure and maturity). Since semen production takes about two months, this is really only a “snapshot” in time of the reproductive status of a bull, but it gives us an excellent starting place and opportunity to address any challenges to their career as breeders.
We are very grateful to Dr. Cale Bjornstad for his thorough and objective services – and as a bonus, he’s an awful lot of fun!