Are We Over-vaccinating Beef-on-Dairy Calves?
The exploding phenomenon of using beef sires to add value to non-replacement dairy calves is creating an unprecedented merging of the U.S. dairy and beef sectors. Along the way, there’s some learning to be done on both sides.
“We love those calves,” declared Dan Thomson, DVM, PhD, who provides health consultation to major U.S. feedlots and also performs research at Iowa State University. “Their genetics have improved considerably in the past few years; they grade very well; and they are a consistent, steady supply of feeder cattle.”
But Thomson said there are some distinct disparities between the lives of full-blood beef calves and their beef-on-dairy cousins before they reach the feedlot. Of particular concern: vaccinations.
“When a beef calf is born, on Day 1 we might give it a clostridial vaccine and an intranasal vaccine,” shared Thomson. “Then at branding around 4 months old, they commonly receive a broad vaccination like a 5-way MLV, and some receive a Mannheimia haemolytica vaccine. And that’s it until weaning. They’re out on pasture with mama for the summer, and we won’t touch them for the next 3 months when it’s time for preconditioning and weaning.”
For calves growing up in the dairy production system, the scenario is much different. At the most recent meeting of the Academy of Veterinary Consultants -- a group of professionals dedicated to feedlot health -- Thomson said there was much discussion on the potential over-vaccination of beef-on-dairy calves.
“The concern stemmed from the fact that consultants are seeing beef-on-dairy calves struggling with bovine respiratory disease (BRD) after entering the feedlot, even though they’ve been given a whole host of vaccinations,” Thomson stated. “Some of our higher-risk populations of cattle for BRD at the feedyard are the beef calves that come in with no vaccinations, and the beef-on-dairy calves that have been blasted with vaccines.”
He said during the first 90-100 days of their lives, calf-ranched-raised calves may receive up to 20 vaccinations, including antigens for various viral respiratory disease agents like IBR and BVD,; and a host of bacterins ranging from blackleg, respiratory disease, enteric disease, pinkeye, and more.
Every vaccine sparks a challenge to the calf’s developing immune system. “I’m not an immunologist, but from a field perspective, it makes one wonder, ‘How many challenges can those little calves take?’” said Thomson. “I’ve seen protocols that call for vaccination on Days 1, 28, 35, 42, 49, 63, and at departure from the calf ranch. That’s very common.”
In addition to the systemic challenge, Thomson is concerned about the pain associated with a near-weekly needle poke. And he said there is research-based evidence that some vaccines change the microbiome of the nasal passages in calves, permanently altering their natural bacterial defenses.
Thomson would like to see the dairy and calf ranch sectors shift their focus away from super-sized vaccine protocols and toward at least four fundamentals that he believes will serve the calves and the industry much better:
- Colostrum delivery – There’s no way to re-create the natural immunity conferred by the passive transfer of immunoglobulins and other helpful agents supplied by colostrum on the first day of life. Thomson said dairy managers have a good understanding of this, but would like to see equal focus on excellent colostrum quality and delivery for replacement and non-replacement calves alike.
- BVD screening – Replacement heifers on many dairies are screened vigilantly, early in life, to cull out persistently infected (PI) BVD carriers. Again, Thomson suggested the equivalent handling of calves headed for the beef supply chain, as he believes BVD caused by PI carriers remains a significant cause of respiratory issues in feedlot cattle.
- Rearing basics – Vaccines cannot make up for inadequate nutrition and water delivery, subpar sanitation of housing and feeding equipment, fly problems, and heat stress, according to Thomson. He said tending to all of those details for calves is more important than any shot you give them.
- Transportation – “Putting day-old baby calves on a truck at their birthplace in the upper Midwest and shipping them to calf ranches in Kansas and west Texas has become a standard practice that I think needs to be adjusted,” stated Thomson. “They might be alive when they reach their destination, but you can’t tell me that it’s good for their immune systems.”
With strengthened communication and possible incentives between the various stages of the beef-on-dairy production chain, Thomson is optimistic about the future, merging veins of the industry.
“I think we’re on a very successful path to a system that benefits every sector,” he said. “You can’t vaccinate your way out of a problem once it’s started, but by tweaking the fundamentals at the ground level, we can create healthier animals with fewer disease challenges and stronger natural immunity.”
