MANHATTAN — Many thriving business owners agree that a key component to their success begins with selecting quality products. 

For cow-calf operations, selecting the right bull to bring into the herd has an impact on their ranch’s bottom line, said the experts at Kansas State University’s Beef Cattle Institute on a recent Cattle Chat podcast. 

Setting a bull budget 

The first step in the selection process is to establish a budget, K-State agricultural economist Dustin Pendell said. 

“Producers should be asking themselves what value will that bull may bring to my herd in terms of future calf sales,” Pendell said, adding that producers also need to see how the qualities of the prospective herd sires match with the goals of the operation and the environmental resources available. 

In herds where the bulls will be siring replacement heifers, K-State beef cattle nutritionist Phillip Lancaster said the value will also include what types of genetic change can that bull bring. 

“Buying a bull is a long-term decision regarding the genetic change; it’s not just estimating how many pounds of weaning weight is he going to add to the calves in the next two years,” Lancaster said.

One exception to this is if the bull is used as a terminal sire, added K-State veterinarian Bob Larson. 

“With a terminal sire, all the calves leave the ranch at weaning or shortly after, so he doesn’t impact the long-term genetics of the herd,” Larson said. 

Yearling bull selection and management 

Once producers have a dollar value in mind, they can begin to evaluate the bull prospects. One important health evaluation is to make sure they’ve passed their breeding soundness exam, Larson said. 

He added those exams are often first done between 11 and 15 months of age when the bulls reach puberty. 

“The most common reason a young bull fails a BSE is because he hasn’t reached puberty; I am going to interpret those results based on how old he was at the time of the test,” Larson said. “For example, if he is 11 months of age and fails, he needs to be retested; but a bull that fails at 15 months of age I am prejudiced against.” 

Once the bull gets home, it is important to give him time to transition to the new ration before turning him out with the cows because yearling bulls sold through an auction are often carrying extra body condition, the experts said.   

To help the bull adjust, Lancaster said it is important to step him down from a grain-based diet and move him to a forage-based diet. 

“If bulls go from the sale to the pasture without that time of transition, they will lose body condition because the rumen hasn’t been able to adapt to digesting forage and he’s not getting the nutrition that he needs,” Lancaster said. 

Also, the experts offer advice on how many cows a yearling bull can be expected to breed. 

“A rule of thumb is that a bull can breed one female per month of age, so if he is a 15-month-old bull, he can be in a pasture with 15 cows,” Larson said. “A mature bull can handle quite a bit more breeding pressure, but we have to be conservative with the yearling bulls on how many cows to put them with.” 

To hear the full discussion, listen to Cattle Chat at  https://ksubci.org/2025/02/14/yearling-bulls-mineral-listener-question-fall-born-calves/on your preferred streaming platform.