As the 2026 spring season rolls in, many cattle producers are beginning to make plans for buying bulls and preparing for annual breeding seasons. Buying a bull isn’t a small decision … At maturity, bulls can breed upwards of 30 cows in one season. That is a lot of genetic influence on the next generation of beef in your herd! Before buying a bull this season, it is essential to understand the importance of breeding soundness exams (BSE) and expected progeny differences (EPD), so that informed decisions can be made to increase the efficiency and profitability of your beef cattle operation.
It is imperative that bulls have breeding soundness examinations completed before the breeding season begins. A BSE is performed by a veterinarian and includes three parts: physical examination, semen evaluation and examination of reproductive organs. When complete, satisfactory BSE results should alleviate any concerns about infertility. If results are unsatisfactory, then reproductive issues within the bull may be identified and treated before he is released to begin breeding cows. Identifying, treating, replacing and/ or removing bulls with reproductive issues can result in significant benefits to the reproductive performance of the cow herd and overall profitability of the operation.
Part one of the breeding soundness exam includes a physical examination to ensure that the bull is in overall good health. Any issues within a bull’s feet, vision, body condition, mobility, structure, etc. should be evaluated. This part of the exam verifies that the bull is physically capable of mounting and breeding females. Part two of the BSE includes an examination of a bull’s reproductive organs. The veterinarian performing the exam should examine scrotal circumference, testicular health and overall health of the reproductive tract. Lastly, the BSE will include an examination of semen for motility, morphology and concentration of sperm cells. The development of healthy sperm cells can depend on several factors. For example, bovine testes should maintain a temperature of around 90°. Any insult to the scrotum that damages the testes and/or impairs their ability to move freely within the scrotum will disrupt the temperature regulation of the testes. Situations that involve frostbite or burns from wildfires can cause permanent damage to sperm cell quality.
Bulls that meet the minimum standards for each part of the BSE will be classified as a “satisfactory potential breeder.” If a bull does not pass minimum standards, then the veterinarian will classify him as either “deferred” or “unsatisfactory potential breeder.” If “deferred”, the veterinarian will most likely recommend a follow-up examination a few weeks following the initial exam. It is important to note that spermatogenesis (the production of sperm) is a 61-day process in bulls, thus, producers should plan to have BSEs completed at least 61 days prior to releasing the bull to begin breeding cows. This window will allow time for new production of (hopefully) healthier sperm cells.
It is important to note that the BSE process does not normally include testing for infectious diseases that may cause infertility or other reproductive problems. Additional testing for diseases such a Trichomoniasis should prevent unwanted infertility and overall health issues within your herd. Libido and/ or social dominance issues will not be detected within the breeding soundness exam, so it is recommended to watch breeding activity of the bull closely to identify these issues early in the season.
Along with implementing BSE information to guarantee reproductive health, producers should also evaluate expected progeny differences if/when selecting bulls to purchase. EPDS are predictions of the genetic transmitting ability of a parent to its offspring and are one of the most effective tools within the beef industry that can be used to estimate the appearance and performance of an animal. EPDs are based on data submitted by producers on the performance and characteristics of parents, siblings, daughters and sons of that bull. They are a comparison tool and should be used to evaluate differences between two animals or compare one animal to its breed average.
In order to use EPDs to aid in buying bulls, think about the details that are important to your operation. How will this bull be used? Will he be breeding mature cows or heifers? Why do you sell calves? Do you sell at weaning or retain for grazing and sell as yearlings? Once you have decided which traits are most important to your operation, you can choose the most fitting EPDS to select for. For example, producers that are selecting bulls that will breed heifers may want to evaluate the EPD value “calving ease direct (CED)” to identify more unassisted births from heifers. For producers that sell calves at weaning, “weaning weight (WW)” would be more beneficial than “yearling weight (YW).”
“Accuracy” is usually an overlooked value within the bull sale catalog. Accuracy is used to indicate the confidence of the EPD values. For instance, Bull A has been used in artificial insemination and has data collected on 50 of his calves. Bull B is a yearling and is being sold this year for his first breeding season. Bull B may have EPD values based on his sire and dam, but he himself has not sired any calves yet. Since there is more data collected on actual progeny of Bull A, he will have an increased EPD accuracy, meaning there is more confidence in his EPD values. Accuracy is a risk management tool that can help producers be more confident in a bull’s EPD values.
If you have any questions regarding EPDs, BSEs, genetics, bull-buying and/or planning your beef cattle breeding season, please contact the Okmulgee County OSU Extension Office at 918-756-1958 or stop by at 1901 N. Oklahoma Ave. in Okmulege.
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