Bull breeding soundness and cryopreservation of semen

Abstract

The Society for Theriogenology (SFT) adopted the current form for the bull breeding soundness evaluation (BSE) in 2018. The BSE consists of four parts: a physical exam, a minimal scrotal circumference by the age of the bull, minimum progressive motility of 30%, and minimum morphology of 70% normal cells. A bull deemed to be a satisfactory potential breeder should unequivocally meet or exceed these four requirements. These standards as set forth by the SFT, give the veterinar­ian an objective approach to evaluating a bull. It has been said that “rarely are bulls infertile, but there are a lot of sub-fertile bulls”. Identification of these sub-fertile bulls by veterinarians, allows cattle producers to negate a potential negative impact on the overall productivity of the herd due to poor reproductive efficiency.

Each part of the exam should be of equal importance to the vet­erinarian and no part should be omitted if an accurate assess­ment of the bull is to be determined. Carson et al in review of BSE trends for the past 20 years, deemed that overwhelmingly the most common cause of unsatisfactory or deferred classi­fication of bulls was due to unacceptable semen morphology. The preparation and interpretation of the morphology slide must be proficient and consistent for the results of the exam to be valid.

The challenges that food animal practitioners encounter re­garding remaining relevant in the livestock industry continue to surface, and the profession must find means to maintain their position in a changing world. Promoting ourselves as ex­perts and the benefits of a professional exam by a veterinarian are essential to suppressing emerging imitators that provide a mediocre version of this exam sometimes referred to as the “se­men check”.