By Jocelynn Jacobs, DVM, CVC, BSC

When you hear the term “mastitis” most of us automatically think of cows. However, mastitis is defined as inflammation and infection of the mammary gland, and since dogs have even more mammary teats than cows (10 on the average, verses 4), they too can suffer from this condition.

Mastitis is caused by a bacterial infection of the gland spread from the teat to the blood vessels. Escherichia coli (E. coli), Staphylococci and streptococci are the most common types of bacteria that cause mastitis. Poor hygiene, trauma caused by puppies, and inverted nipples may all contribute to mastitis.

Mastitis commonly occurs a few days to a few weeks after giving birth. It can even develop during a false pregnancy. There may be one or more glands that are warm, painful, reddened and swollen. Glands located closer to the back legs are more commonly affected. Dams may have a high fever, act anxious or agitated, and won’t eat or drink well. As time progresses, their fever continues to rise and they may become lethargic. They may or may not have discharge from the gland. Some glands with mastitis will produce brownish, bloody or yellowish milk discharge, while some glands produce no discharge at all. If left untreated, some glands will actually “blow out,” rupturing, causing a large bloody hole usually at the base of the gland. Puppy mortality can be seen if the dam is not cared for and treated by a veterinarian immediately.

Treatment of mastitis involves the use of antibiotics and fluid replacement, assuring dehydration does not occur. Because milk is primarily water, the dam diverts most body water to the mammary gland for milk production. When mastitis occurs, the dam does not drink enough to ensure water is available for her as well as her milk, so dehydration is commonly seen.

Choosing the correct antibiotic to treat mastitis can be a challenge. Antibiotics will pass through the mother’s milk to her pups, so care must be taken in determining the appropriate antibiotic to treat the mastitis, but in turn, not detrimentally affect the puppies. Your veterinarian will choose which antibiotic is best for your bitch with mastitis. If the mastitis is severe or puppy mortality is a concern, your veterinarian may recommend hand-raising the puppies while your bitch is being treated.

Every breeder should pay close attention to the mammary glands of their dams postpartum, and watch for any behavior changes or fevers that might develop. Shaving hair around the mammary glands and cleaning the glands with a mild, diluted soap just before whelping is encouraged to keep the glands free from excessive bacteria. Mastitis is not just for cows, and actually may be more common in dogs than the average breeder thinks!