Causes
After the season, hormonal changes prime the uterus, which becomes susceptible to bacterial infection. It affects unspayed females of middle age and older.
Diagnosis
Ultrasound (shows the uterus full of pus) + blood tests. A history of a recent season is a strong pointer.
Treatment
EMERGENCY: the treatment of choice is surgery to remove the infected uterus, together with fluid therapy and antibiotics. It is a life-saving operation.
Prevention
SPAYING prevents pyometra completely. It is the most important medical reason to spay females that are not going to be bred from.

