Breeding soundness exams (sometimes referred to as a BSE) keep Joe Dalton awake at night. More specifically, the lack of breeding soundness exams keeps him awake.

The University of Idaho animal scientist told attendees at the Applied Reproductive Strategies in Beef Cattle symposium Sept. 4-5, 2024, in Athens, Ga., that based on a 2020 National Animal Health Monitoring System (NAHMS) survey, anywhere from 51% to 96% of producers get breeding soundness exams on purchased, leased or borrowed bulls. The 67% average doesn’t sound too bad. Yet, what about the percentage of producers who test bulls already in their bull battery for at least two breeding seasons?

“Here’s where the wheels fall off,” Dalton said. “We’re at 24% up to 67% for an average of 31%. This is problematic because of the value of reproduction to our business.”

A complete breeding soundness exam, not just a semen test, is necessary, he emphasized.

“Complete means a physical examination: eyes, feet and legs. The primary cue to a male of a female in heat is eyesight. The testes, of course; the epididymis; the penis and prepuce; the seminal vesicles; prostate; and both ampullae need to be examined,” Dalton said. “We need to understand scrotal circumference. Is it appropriate for the age?” Scrotal circumference is correlated with paired testes weight and sperm production.

Yes, a semen test is part of the breeding soundness exam. Both semen motility and morphology are examined under a microscope.

“From there,” explained Dalton, “if a bull is classified as a satisfactory potential breeder, there are no guarantees. However, it does mean the bull has met the minimum criteria for scrotal circumference, sperm motility and morphology, and that he’s free of physical problems.”

A bull can be classified as an unsatisfactory potential breeder or could be deferred, Dalton clarified. “When a bull is deferred, in general, the bull is thought to possibly improve with time, and the retest should occur after 60 days.”

What’s magical about 60 days? Dalton said producers will tell him they really need the bull to be working in three weeks.

“Complete means a physical examination: eyes, feet and legs. The primary cue to a male of a female in heat is eyesight.” — Joe Dalton

“We can’t hurry spermatogenesis. Spermatogenesis, the production of sperm, takes 60 days in the bovine. That’s all there is to it,” said Dalton.

When it comes to a complete breeding soundness exam, you don’t have to just take Dalton’s word for it. He said there is a volume of data available. There was a 10-year study out of Michigan with almost 3,000 beef bulls. After complete breeding soundness exams, 82% of bulls were satisfactory, 15% were deferred and 3% were unsatisfactory. In a second study, 1,200 breeding soundness exams on beef and dairy bulls were done and 37% were unsatisfactory.

“That keeps me awake at night,” said Dalton. “That’s a huge problem.”

There was also a study done with 200 Holstein bulls between 12 and 15 months of age.

“They were plenty old at 12 to 15 months of age, but 36% were unsatisfactory,” said Dalton. “Here’s the kicker: 57% of those bulls failed because of the physical exam alone. That’s why a semen test, taking a sample, looking at motility, looking at morphology and saying, ‘Yep, all is good,’ is not sufficient.”

True, breeding soundness exams aren’t free. Dalton says the exact cost depends on how many bulls you have to test and how far you are from the veterinary clinic.

“It could be $50 a bull. It could be $65,” he said. “However, there’s a return on investment — $20 each for $1.”

Plus, Dalton would sleep better at night, and you might, too.

Editor’s note: Becky Mills is a freelance writer and cattlewoman from Cuthbert, Ga. [Lead photo by Lynsey McAnally.]

Angus Beef Bulletin EXTRA, Vol. 16, No. 9-B