This excellent photograph above, submitted by Cat Angus, shows Hope's [Cat's Mastiff bitch] uterus, filled with pussy infection, at the time of spay for pyometra. The uterus should be about the size of a garden hose or a rope, or about the outside diameter of the fingerholes in the clamps (which are approximately 6" long) shown in the picture.

There are two types of pyometra, open and closed. Neither should ever be taken lightly. At the onset of any symptom the bitch should be taken to the veterinarian at once. Of the two forms, open pyometra is the least severe because the cervix is open and allows drainage of the pus. In some open pyometra cases the condition has been mistakenly diagnosed as an aberrant heat. The abnormal vaginal discharge is foul smelling, of creamy consistency and tomato soup in color (although it can begin as a greyish color before turning to soup hue).

The closed form has no avenue to drain since the cervix is not open, consequently the pus builds up inside the uterus, intensifying and spreading the infection until the bitch's life is in jeopardy. In the case of closed pyometra, because the uterus enlarges due to an accumulation of pus, there will be a pronounced swelling of the abdomen. Other signs of this infection are a noticeably increased thirst, increased urination, fever, extreme lethargy and overall weakness. When clinical blood work is performed it will reveal an elevated white blood cell count.

This picture is an excellent graphic to show the true tomato color
of the abnormal discharge produced by the infected uterus.

The condition has often been blamed on hormonal imbalances. It was once thought to occur only in older bitches who had irregular heat cycles, although mismate shots administered to abort ill conceived litters are also known to have caused pyometra. The infection will most often develop within weeks of going out of heat, whelping a litter, or after being bred and missing conception. The earlier pyometra is diagnosed and appropriate therapy begun, the better the chance of preserving the bitch's uterus.

This picture shows the uteus of a spayed Neo bitch
that got bred accidently. The vet estimated there were
13-14 puppies in this healthy uterus.

The treatment of choice is difficult for the bitch. My bitch was treated with high dosages of antibiotic and received two daily injections of prostaglandins for more than a week. The stinging shots are intended to cause hard uterine contractions to squeeze pus out of the uterus. Immediately after the shots are administered the bitch should be walked for at least 30 minutes, as this helps her endure the treatment with less discomfort. The treatment causes vomiting, and it can cause diarrhea.