Mastitis = inflammation in the mammary gland.
Mastitis is usually caused by an infection which has entered via the teat, through a skin wound caused by a puppy, or via the bloodstream.
The teat and breast tissue will be warm and may be swollen and tender. If the mastitis is more severe, there may be loss of milk production or possibly a brownish coloured milk.
Because severe mastitis is very painful indeed, the bitch is unlikely to allow suckling from the affected gland and, in very severe cases, may refuse to allow any suckling at all.
With the more severe cases, the bitch may also have a high temperature, be off her food and possibly even require an intravenous drip.
Treatment
Warm compresses and gentle exercise can help relieve the discomfort of mastitis but, in more severe cases, antibiotics may be necessary. Drugs to help lower the temperature and ease the discomfort and pain of the gland can also be given.
It is important to bare in mind that should antibiotics or other drugs be given to the bitch, the puppies must be hand-fed or weaned.