Beef-on-dairy calves have long been a solid income stream on many dairies, turning into a steady payout when they leave the farm and move into beef systems. More recently, farmers have also started to notice these calves often require fewer individual health treatments than their purebred counterparts, adding to their overall profitability.
Researchers like Melinda Kovacs, a master’s student at the University of Guelph, have started to take a closer look at how these calves perform early in life, when most health challenges tend to show up. One pattern that keeps surfacing is that crossbred calves tend to have fewer digestive issues than Holsteins, especially scours.
In her work, Kovacs found beef-on-dairy crossbred calves have lower diarrhea rates, fewer days with scours and fewer repeat treatments than Holsteins during the rearing phase.
“Producers were finding that the health of these crossbred calves was improved,” Kovacs explained during a recent “The Dairy Health Blackbelt Podcast” episode. “They were finding less health challenges, or these animals were able to recover from disease a little bit better than the purebred calves.”
Fewer Scours Cases Stand Out
The study followed approximately 640 calves housed at a single calf-rearing facility over about 18 months. Kovacs analyzed records from 446 Holstein calves and 194 beef-on-dairy crossbred calves.
Using twice-daily health scoring, Kovacs and her team monitored diarrhea and respiratory disease while also collecting weekly body weights, milk intake and starter feed intake data.
When she compared the two groups at the conclusion of the study, one health challenge stood out immediately.
“We found that the Holstein calves had a higher incidence of diarrhea compared to the crossbred calves,” Kovacs says. “We also found that translated to fewer days with diarrhea.”
The same trend appeared when she evaluated severe diarrhea cases.
“This is what we were expecting based on kind of our communication with producers,” Kovacs says. “That the crossbred calves would have less diarrhea in the preweaning or the rearing phase.”
For dairy farmers and calf raisers, fewer scours cases can influence nearly every part of calf performance. Diarrhea remains one of the most expensive calfhood diseases on dairies due to treatment costs, lost growth, labor demands and long-term health setbacks.
Crossbred Calves Needed Fewer Repeat Treatments
Kovacs also examined therapeutic interventions and found another difference between the groups.
“We did find that the Holstein calves had a higher hazard of being treated multiple times for both diarrhea and respiratory disease,” she says.
Respiratory disease rates themselves were similar between breeds, but the need for repeated treatment was higher in Holsteins. That finding could become more important as dairy and calf-rearing operations focus on reducing antibiotic use while still keeping calves healthy and performing well.
“Perhaps there’s a greater ability of these crossbred calves to recover from diseases compared to Holstein calves,” Kovacs adds.
Why Are Beef-on-Dairy Calves More Resilient?
The study wasn’t designed to pin down exactly why the differences are showing up, but Kovacs thinks genetics likely play a role.
“In the dairy industry, we see a lot of inbreeding depression with the Holstein animals,” she says. “And I think perhaps we have some heterosis or hybrid vigor in these crossbred animals.”
Selection pressure may also contribute to the performance gap. Dairy genetics have focused on milk production traits, while beef genetics have emphasized growth and muscling.
“In the dairy industry, we’ve been genetically selecting for obviously higher milk production, whereas in the beef industry, we’ve been selecting for more growth traits,” Kovacs says. “So perhaps these crossbred calves are benefiting from the growth traits compared to the Holstein calves.”
She also found crossbred calves gained weight faster during the rearing phase.
“The crossbred calves did have higher growth rates, so higher average daily gains,” Kovacs says. “They were about [15 lb.] heavier than the Holstein calves when they were finished this rearing phase.”
Differences Continued Through Harvest
Kovacs and her team later expanded the project to follow some calves from birth through harvest at approximately 13 months of age. She wanted to better understand how calfhood health and management influence later feedlot and carcass performance.
“Right now, there’s kind of a big disconnect between all of the different components of the industry, between the dairy farm of origin, the rearing, the feedlot and the abattoir,” Kovacs says.
The performance differences continued beyond the early rearing phase.
“The crossbred calves, I believe, were about [120 to 124 lb.] more in body weight compared to the Holsteins,” Kovacs says. “Which does have significant implications in terms of the cost benefit of these animals.”
She also identified differences in ribeye area and carcass composition, suggesting the advantages weren’t limited to early growth but carried through to how the animals finished at harvest.
More Research Still Needed
Even with the encouraging results, Kovacs says dairy producers should not assume crossbred calves require less attention or lower-quality care.
“With my findings, we see that they’re maybe more resilient or robust,” she says. “But I think those producers still need to be offering the best care to those calves to ensure their success.”
Kovacs adds that much of the existing calf research has historically focused on purebred Holsteins, leaving major knowledge gaps around nutrition and management requirements for beef-on-dairy calves.
“A lot of research that’s been done in the past has focused on purebred Holstein calves,” Kovacs says. “So, we don’t really know if the requirements of these crossbred calves for both maintenance and growth are the same as for a purebred Holstein calf.”
As beef-on-dairy programs continue to expand across the dairy industry, producers are paying closer attention to which calves stay healthier and perform better from start to finish. This research suggests fewer scours cases early in life may be part of the advantage, adding to the overall profitability of beef-on-dairy calves.
