What causes mastitis in cows?

Bacteria are frequent causes. Exposure can come from contaminated bedding, mud, water, milking equipment or hands, while damaged teat skin and poor teat condition can make entry easier. Some organisms spread between cows during milking; others come mainly from the animal's surroundings.

Bovine mastitis is inflammation of one or more mammary glands. A clinical infection may change the milk and cause heat, swelling, firmness or pain in an udder quarter. A cow may also eat less, seem dull or become generally unwell. Subclinical infection can be present without obvious udder changes and is found through herd milk monitoring or tests on an individual cow.

This animal condition is different from mastitis in a breastfeeding person. Human breast pain, redness, fever or painful feeding should be assessed using human medical guidance, not livestock treatment advice.

Separate visibly abnormal milk from the food supply and contact a veterinarian for an examination and a milk-sampling plan. The appearance of milk alone cannot identify the organism. Treatment depends on the cow's condition, the affected udder quarter, test findings and locally applicable medicine-withdrawal requirements. Do not use a human medicine or leftover antimicrobial in a cow.

Review the milking routine, equipment cleanliness, teat preparation, post-milking hygiene and bedding moisture. Keep teats clean and dry, use products intended for cattle as directed, and record which cow and quarter are affected. These details help the veterinarian distinguish an individual case from a herd-level pattern.

Seek prompt veterinary help if the cow is weak, unable to stand, not eating or drinking, has a markedly swollen udder, or produces watery, bloody or otherwise abnormal milk. A cow that appears systemically ill may need supportive treatment as well as investigation of the udder infection.

Arrange veterinary review when several cows develop signs, cases recur, or milk monitoring suggests hidden infection. A cluster may point to contamination in housing or milking, or transmission between animals, and requires a herd-specific control plan.

Ask which milk sample or herd records would help identify the cause, whether the cow needs isolation or supportive care, how her milk should be handled, and which parts of the housing or milking routine should be checked. If your concern is about breast symptoms in a person, tell a human healthcare professional about fever, redness, a painful area and any breastfeeding difficulty.