Cattle Chat: Evaluating Bulls Before Breeding Season

By Lisa Moser, K-State Research and Extension news service
 
Manhattan, KS— Whenever there is an important job to do, a little preparation goes a long way to a successful outcome. And for bulls with the job of breeding females, it is important to make sure they are fit before turnout, said Kansas State University veterinarians on the Beef Cattle Institute’s recent Cattle Chat podcast.
 
“It is important to check the bull ahead of every breeding season because if he isn’t where he needs to be in terms of physical condition and sperm quality, then producers will end up with a bunch of open cows at the end of the season,” said veterinarian Bob Larson.
 
He said there are three elements to the exam.

  • Physical evaluation of the bull’s feet and legs and musculoskeletal structure.
  • A close examination of the reproductive organs to include the penis and scrotum.
  • Semen evaluation for both motility and abnormalities.

“This is a pass/fail exam,” Larson said. “Bull behavior is complex and hard to predict so we can’t rank bulls on fertility until the calves are born and we see how many cows they bred.”
 
Oftentimes beef cattle producers test yearling bulls before turnout, but Larson and fellow veterinarian Brian Lubbers agreed that mature bulls need to be tested, too.
 
“There are a lot of things that can happen from one breeding season to the next in terms of disease and nutritional stress,” Larson said. “Semen production is pretty sensitive to stressors.”
 
Lubbers added: “Injuries can occur and go unnoticed, which can lead to a decrease in semen production or issues with the musculoskeletal system.”
 
Veterinarian Brad White shared that with mature bulls, producers sometimes make the mistake of assuming the bulls are fit for breeding because they were in the past.
 
“Even though older bulls look okay, there are other factors that may have negatively influenced their semen production making them not suitable for breeding the cows,” White said.
 
White summarized the thoughts of the veterinary team when he said, “Annual breeding soundness exams for all bulls are important to the success of the operation.”
 
To hear the full discussion, listen to the Cattle Chat podcast online.