When a cow shows up in the parlor with clots in her milk, the clock starts ticking. Will treatment restore her quickly to the herd, or will it end with wasted drugs, discarded milk, and frustration?
For decades the answer was almost automatic: reach for antibiotics. However, Dr. Pamela Ruegg of Michigan State University suggests that the future of dairy health management depends on asking a different question: How do we know that we’re using the right amount of antibiotics?
Twenty years ago, Ruegg conducted a survey asking dairy producers about their perceptions of utilizing antibiotics on their farms and found that 80% of them thought they used the right amount. In a recent online survey of Wisconsin and Michigan veterinarians (unpublished), Ruegg asked vets about their perceptions of prescribing antibiotics for dairy cattle. She found that 85% of veterinarians said they felt they were prescribing the right amount, while 15% of veterinarians said they prescribed too many.
“Look at that. Twenty years difference. Similar populations: dairy producers vs. dairy veterinarians. We believe we’re doing the right thing. But the next question that comes out is: How do you know what the right amount is?” proposed Ruegg.
Looking across 40 surveyed farms in Wisconsin, the number of defined daily doses per adult cow per year varied widely. This data shows that while producers and veterinarians may feel they’re using the right amount of antimicrobials, this doesn’t mean the same thing from farm to farm.
If you’re interested in seeing how your farm’s antimicrobial usage compares to others, the Top Milk program of Michigan State University has created an Antibiotic Usage Benchmark Tool.
Changing the Way We Treat Dairy Cattle
Mastitis and dry cow therapy remain the two biggest reasons antibiotics are used in dairy cattle. When looking at the quantity of antimicrobials sold in the U.S. for cattle in 2022, intramammary administration accounted for less than 1% of the total mass. While this overall proportion of antibiotics used in dairy cattle is relatively small, there are still opportunities to improve and reduce costs for producers. For veterinarians, that opens both a challenge and an opportunity: ensuring herds receive the treatments they need while cutting down on unnecessary exposures.
Ruegg encourages livestock workers to live by the mantra, “if you don’t measure it, you can’t manage it.” She proposes the following framework:
- Establish standardized methods. Define your antimicrobial usage. Consider using Defined Daily Doses per cow per year.
- Create benchmarking reports. These can allow farms to compare similar herds, flag outliers, and observe trends over time.
- Follow a four-month stewardship cycle. Perform a quarterly review of antimicrobial usage and protocols.
These steps create a cadence of check-ins and ongoing improvement, but remember that there is no “one size fits all”; apply whatever protocols work best for your herd.
Reduced Antimicrobial Use, Not Zero Use
At the heart of antimicrobial stewardship is deciding when not to treat or how to treat most effectively.
According to Dr. Michael Zurakowski from Quality Milk Production Services (QMPS) at Cornell University, only 15% of all mastitis cases are severe: “The other 85% are mild or moderate, giving us the opportunity to do some diagnostics.” He encourages the adoption of on-farm culturing to determine what pathogen is causing the issue in your animals. “When we implement these pathogen based treatment mastitis protocols, we see a significant decrease in antibiotic use on the order of 60[%]-70%. That equates to a pretty good savings in cost.”
If this is a route you think may work on your farm, QMPS has put together an online culture education module to help you with setup, sample collection, pathogen identification and treatment decisions.
Closing Thoughts
Antibiotic stewardship isn’t about using less for the sake of using less; it’s about making informed decisions for the sake of more — more healthy cows, more trust from consumers and more longevity for the drugs we rely on. With data-driven tools, economic reasoning and veterinary leadership, stewardship can become less of a burden and more of a blueprint for the future of dairy management.
