Bull Testing Season is Here

A thorough Breeding Soundness Examination (BSE) is a crucial component of effective bull and herd management. At True North Veterinary Services, we are committed to upholding the highest standards in conducting BSEs.

Our comprehensive exams begin with an external physical assessment. We evaluate the bull's feet to check for lameness, assess any potential genetic defects that could be passed down, and look for signs of conditions like cancer eye, etc. We also thoroughly inspect the reproductive system, including the penis, sheath, testicles, and accessory sex glands. During this process, we look for any signs of infection, warts, or other factors that may hinder the bull's reproductive capability. We also assess scrotal size, symmetry, and firmness, as these factors can impact the bull's fertility. Through physical assessments we may discover conditionals that may affect the longevity of the bull through breeding season.

Following this physical evaluation, we collect a representative semen sample—more than just a simple drop on a slide. Under the microscope, we analyze sperm motility and morphology. We use a cell counter to provide a detailed breakdown of sperm quality, including the percentage of normal versus abnormal sperm and categorizing the different types of abnormalities.

Based on the results of the Breeding Soundness Exam (BSE), a bull is classified as satisfactory, unsatisfactory, or deferred. A satisfactory bull meets the minimum requirements in all categories and shows no physical issues. Bulls that fail to meet the minimum standards in any category are considered unsatisfactory or deferred. Deferred bulls should have a reevaluation scheduled at least 30 days later. Unsatisfactory bulls are unlikely to improve, while deferred bulls may benefit from treatment or additional time and could pass a future breeding soundness exam.

There are various reasons why a bull might not pass the breeding soundness exam. Injuries or frostbite could impair the bull’s ability to produce healthy sperm, while issues with its feet, legs, or hips may prevent it from mounting and breeding cows, even if it has a sufficient number of healthy, motile sperm cells. Additionally, yearling bulls may not yet have reached sexual maturity, which decreases their chances of passing the exam. In any of these cases, the bull may be unable to breed cows effectively.

By identifying bulls that fail a breeding soundness exam, we are able to keep infertile and sub-fertile sires out of herds, which is progress towards improved reproductive efficiency.

While passing a BSE is important, successful breeding also requires careful observation of your bulls throughout the season. Even if a bull passes his BSE, his behavior and motivation to breed should be monitored. Some bulls may lack the drive to breed, while others may sustain injuries that limit their reproductive abilities. Regular observation is essential to ensure the bull's continued effectiveness during breeding.