Mastitis occurs when the udder becomes inflamed because leukocytes are released into the mammary gland in response to invasion of the teat canal, usually by bacteria. These bacteria multiply and produce toxins that cause injury to milk secreting tissue and various ducts throughout the mammary gland.

What is the main cause of mastitis in cows?

Mastitis in dairy cows is caused by udder infections, usually resulting from bacteria introduced either during the milking process or from environmental contact. Examples include contamination from milking equipment, milking personnel, manure contamination or dirty stalls.

How is mastitis spread in cows?

Mastitis is most often transmitted by repetitive contact with the milking machine, and through contaminated hands or materials. Another route is via the oral-to-udder transmission among calves.