Conditions or ailments that are the cause of a problem that you see - your observation.

Your vet may diagnose


Synonyms: Chronic Closed Infection of Uterus


Pyometra is a chronic uterine infection, typically caused by a cervix that does not open normally. It overlaps with the diagnosis of endometritis.

In a pyometra, infection takes hold and continues because the uterus cannot empty or clear the infectious agents. The uterus fills with pus and becomes akin to a huge abscess. In cases of a severe pyometra, the uterus may contain 5 gallons of pus or more.

This closed infection makes the mare feel terrible, causing lack of appetite, fever, and colic signs due to stretch on the uterine wall. Treatment involves a combination of opening of the cervix, drainage of pus, uterine flushing with antibiotic treatment. Ultimately, surgical removal of the uterus (hysterectomy), may be required. In most cases, mares that have a pyometra become permanently infertile.

my vet's role


There is a high rate of recurrence. The factors that led to the pyometra in the first place cause it to recur. Ultimately, in many cases, hysterectomy is the only long term solution.

my role


I might observe

You might make these observations when a horse has this condition.

Very Common
Less Common
more observations

Questions To Ask Your Vet:
  • What are the chances that I can breed or rebreed this mare?
  • What underlying condition contributed to the development of this problem?

Early treatment of uterine infections. Recognition and treatment of cervix disorders that predispose this development.

further reading & resources

Author: Doug Thal DVM Dipl. ABVP