Extension Marathon County

Help Protect your Herd: Join the Milk Quality Study
Could your herd have an undetected threat?
Prototheca bovis is a newly recognized mastitis-causing pathogen with no known cure—and it could be silently impacting your herd’s milk quality. Because this slow-growing algae is often outcompeted in standard cultures, it remains undetected until bulk tank somatic cell counts rise.
UW-Extension needs your help to uncover how widespread Prototheca bovis is on Wisconsin dairy farms.
By participating in this study, you will:
✅ Get a free Prototheca bovis screening using specialized agar designed to detect this hidden pathogen.
✅ Better understand your herd’s health by testing 10 high-somatic cell-count cows.
✅ Take proactive steps to safeguard your milk quality and prevent costly surprises.
How to Participate:
Sign up at: https://go.wisc.edu/milk. We’ll coordinate with you to collect quarter milk samples—or, if preferred, you can collect them yourself. All samples will be cultured, and Marathon County DHIA will analyze somatic cell counts.
Don’t wait until it’s too late—help us uncover Prototheca bovis's true impact and protect your herd.