How Beef on Dairy Selection Impacts Beef and Dairy Production with Dr. Tara Felix, Penn State University; Dr. Brad Johnson, Texas Tech University

This episode was recorded at the 2025 Florida Ruminant Nutrition Symposium. Dr. Felix and Dr. Johnson begin with brief descriptions of their background and interest in beef on dairy research. (3:15)

Dr. Felix’s first study in this area compared dairy calves with beef on dairy calves of unknown origin. They were placed in the feedlot and fed and implanted the same. Beef on dairy calves grew faster, but they ate more, so there was no difference in feed efficiency. They also had larger ribeye areas and slightly heavier carcass weights. In subsequent studies, calf growers indicated that beef on dairy calves were more hardy and got a quicker start in the calf systems. (9:16)

Dr. Johnson and Dr. Felix are both fans of using Charolais sires in beef on dairy systems. Dr. Felix emphasizes that while breed can be important, individual sires within breeds really make the difference when it comes to successful beef on dairy systems. (13:23)

The beef and dairy industries speak two different languages when it comes to genetic selection. Dr. Felix encourages education efforts across both segments to speak a common language. Bull studs are heavily invested in this effort. Just 2.5 million units of beef semen were sold in the US in 2017, compared to 9.4 million units in 2024. (16:15)

The use of beef sires increased gestation length by two days in one study of over 10,000 dairy records. Dairy producers may have to manage the dry period of beef on dairy cows differently to avoid loss of milk production. (20:46)

Last year, the National Association of Animal Breeders published a new category in their annual semen sales report: heterospermic beef, at 1.5 million straws. Genetic companies have started to market straws containing semen from two to three different beef bulls who have similar desired traits. The literature suggests that different cows’ reproductive tract environments have different “preferences” for semen. The theory behind heterospermic beef is by putting more than one bull in a straw, we may see increased fertility for that straw. (27:52)

Dr. Felix explains her sire selection process from her USDA research. Regardless of breed, she focused on yearling weight, carcass weight, and ribeye area. Because of this, little difference was found between breeds since the same terminal traits were of priority. Dr. Johnson agrees that the growth of beef on dairy has been beneficial to feedlots and that the beef cattle industry can learn from the beef on dairy systems. (32:36)

What challenges still exist with beef on dairy? Dr. Felix suggests we need to get past the block of dairy beef “only being 20% of the fed cattle” - why shouldn’t that 20% be as high quality as possible? Health will continue to be a challenge, particularly in the areas of liver abscesses and respiratory disease. (41:46) 

Adequate colostrum intake is critical for successful beef on dairy calves. Dr. Felix describes a project where calves who had adequate passive immunity were heavier at nine months of age than calves who had failure of passive immunity. Dr. Johnson concurs and reminds listeners that colostrum also contains bioactive components that appear to have value beyond immunity, even after gut closure. (44:36)

Dr. Johnson gives some perspective from the cow/calf side of the beef cattle industry regarding beef on dairy. He feels that there is much to learn from beef and dairy systems that can be applied to the cow/calf sector. Dr. Felix has received pushback from cow/calf producers that she’s trying to “put them out of business.” She counters that we had 20% dairy influence in fed cattle when they were Holstein, and there is still 20% dairy influence now that they’re crossbred cattle. We’re not changing how many calves come from the dairy industry each year, but we are increasing the amount of beef produced. (47:52)

Each panelist wraps up with their take-home messages. Dr. Zimmerman was interested to learn ab