What should you know about subclinical mastitis in cows?

Unlike clinical mastitis, subclinical mastitis may not cause obvious swelling, heat, pain, or visibly altered milk. The cow can appear well while inflammation affects milk quality or production. A raised somatic cell count or other milk test can alert a farmer or veterinarian, but a test result needs interpretation alongside the cow’s history, milking routine, and herd pattern. It is a veterinary condition in cattle, not a diagnosis of human breast inflammation.

Ask a veterinarian to confirm the finding and decide whether a milk culture or repeat testing is appropriate. Review milking hygiene, teat preparation, equipment function, bedding cleanliness, and records for recurring cases. Keep affected animals clearly identified and follow the veterinarian’s treatment and withdrawal instructions exactly. Do not give human medicines or leftover animal drugs without veterinary direction. A lactation consultation is intended for human breastfeeding and is not a substitute for cattle veterinary care.

Call a veterinarian promptly if the cow develops a hot, swollen, hard, or painful quarter, clots or watery milk, fever, poor appetite, weakness, or a sudden drop in production. These are signs that inflammation may have become clinically apparent. Milk from an animal under treatment should be handled according to veterinary advice and not entered into the food chain until the required withdrawal period has passed.

Which test supports the diagnosis in this cow? Is a culture needed before treatment? What milking or housing factors should we correct? How should milk be managed during treatment, and when should the cow be retested?