DNA testing in cattle can provide a growing list of information regarding specific traits important in genetic selection, but for many producers, one of the simplest pieces of data could be the most valuable. That is, which bull sired a calf?

“The ability to identify parentage on calves when more than one sire is present can be a great advantage for commercial producers,” says Igenity technical services specialist Jim Gibb, PhD. “This helps producers evaluate both superior and inferior sires while receiving the benefits of improved reproductive and pasture performance that is associated with multiple-sire pastures.”

The first measure of a bull’s performance is how many calves he sires, which parentage ID can help measure. “It is not cost-effective to keep a sire around that is not producing calves, and unless parentage is identified on the calves, it is impossible to know for sure if each sire is pulling his weight,” Gibb says. He cites an example of a ranch that tested parentage and found that bulls ranged from producing as few as three calves to as many as 23.

Another trait associated with a bull’s performance is the instance of calving problems. Gibb provides another example in which a producer kept track of cows that had calving difficulty. Then, he identified parentage on those calves and found that two bulls produced the majority of the calves in question.

By identifying non-productive bulls or sires associated with calving difficulty, producers can make informed culling decisions that could significantly improve reproductive performance in their herds.