Recovery of contagious equine metritis organisms and development of lesions in experimental infection of mares.

Twenty-three of 24 mares were infected experimentally with contagious equine metritis organisms by intrauterine inoculation, and killed 2-116 days later. From mares killed within 14 days after infection the organism could be recovered from many sites in the uterus, and most sites in the cervix, a few sites in the vagina and oviduct and from one clitoral sinus. At this time the endometrial folds were swollen and there were 10-20 ml of fluid in the uterus. In mares killed after 14 days, the organism was recovered from the ovarian surface (1 mare), oviduct (4 mares), uterus (2 mares) and the clitoral sinus (3 mares). Severe diffuse endometritis and cervicitis was initially acute, and became more severe subacute and predominantly plasmacytic by 14 days, then declined but persisted throughout the experiment.