Optimizing mastitis treatment costs using benchmarking data

Jaimie Strickland and Pamela Ruegg<plruegg@msu.edu>, MSU College of Veterinary Medicine and MSU Extension. - August 06, 2025

New tools for economic analysis.

black and white cows eating brown food — Photo by MSU Extension.

Treating mastitis in dairy cattle costs money, but exactly how much does treating each case cost your farm? For many dairy farms with high-producing cows, the cost of milk withhold far exceeds the cost of the antimicrobials. Milk withhold cost when treating mastitis increases each day milk cannot be sold, so longer treatment durations are associated with higher costs than the label minimum duration. The label minimum is determined by efficacy studies and is likely to be effective on your farm outside of unusual or extenuating circumstances. Contact your veterinarian if you believe this is the case on your farm. Past research from the Ruegg lab confirmed that there was no difference in treatment outcome when comparing three-day vs five-day treatments of Spectramast LC. Choosing to treat based on milk appearance often results in a longer treatment duration than necessary. Milk can still appear irregular even when the mastitis bacteria are no longer growing and dividing.

Can I save money?

Dr. Ruegg’s lab hosts the Antibiotic Usage Benchmark Tool, a secure online program that allows farms to enter their electronic treatment records and learn how their antibiotic usage compares to that of other farms. An exciting new feature compares the farm’s current cost of antibiotics and milk withhold compared to the cost of the minimum label duration antibiotics and milk withhold. For example, a farm spent over $187,000 treating 1,032 cases of mastitis with 5 days of Spectramast LC. If this farm treated for only two days, the inimum label duration, they could save over $74,000. The farm could also realize additional savings from decreased labor and supply costs as well.

Milk withhold.png — Reducing the treatment duration for mastitis may save money in antibiotic costs, and more significantly in reduced milk withhold.

How does my farm compare?

The Benchmark Tool uses data from 37 large midwestern dairy farms to compare costs to a farm’s records. This includes the average cost of treating a case of mastitis with antimicrobials, the average milk withhold days and the average daily milk production. If your milk withhold days are much higher than average, especially on a farm with high-producing cows, you may consider reducing the duration of your mastitis treatment protocols.

Reduce treatment duration 2 SD Summer 25 web.jpeg — Reducing the treatment duration for mastitis may save money in antibiotic costs, and more significantly in reduced milk withhold.

Want to learn more?

You can input your treatment records at dairyantibioticbenchmark.msu.edu. The whole process takes about an hour.

Want additional support?

Email cvm.benchmarkhelp@msu.edu to set up an appointment with a team member for personalized assistance.

This article was published by Michigan State University Extension. For more information, visit https://extension.msu.edu. To have a digest of information delivered straight to your email inbox, visit https://extension.msu.edu/newsletters. To contact an expert in your area, visit https://extension.msu.edu/experts, or call 888-MSUE4MI (888-678-3464).