[Endometrial cysts in the mare. 1. Post-mortem studies: occurrence and morphology]

During macroscopic post-mortem examinations of the genital tract in 104 mares endometrial cysts occurred in 14 (13%) cases. Whereas in mares up to the age of 10 years cystic changes were absent, endometrial cysts occurred in 19% of the animals above the age of 10 years. In 6 mares only 1-2 cysts per uterus were found, and in 8 animals there were between 5 and 18 cystic changes per organ. The cysts were equally distributed in the uterus body and horns. Sporadically occurring cysts were about 11 mm in diameter with a decreasing size to a mean value of 5 mm in multiple cysts. Predominantly in the uterus body very large cysts were found. The largest endometrial cyst was of 30 mm in diameter. Classification into lymphatic cysts and glandular cysts was made based on histological examinations.