All Archived Publications

Understanding Bull Breeding Soundness Exams

Clell V. Bagley DVM, Utah State University


Controversy still exists about Breeding Soundness Examinations (BSE) and what they can and cannot do. At times they are not used because of a lack of understanding of their value while at other times they are used with unrealistic expectations. First, BSE is performed to identify bulls with reduced fertility not just to find those which are sterile. Very few bulls are sterile but a significant percent have reduced fertility. A second important point is that a BSE is like a “snapshot” in time of the reproductive status of the bull. Even a bull classed as “Satisfactory” does NOT mean he will always be an acceptable breeder. The reverse could also be true for some conditions. Semen production takes about two months, so the semen used on the first day of the breeding season was started into production about 60 days prior. Even heavy breeding use does not speed up the process of sperm production.