[Fertility in mares after an disturbed as well as an undisturbed puerperium. Significance of histological and cytological examinations of the uterus].

Because of the mare's ability to conceive very soon post partum a thoroughly performed control of the puerperal period is of particular importance. Cytological examinations of uterine content and histological examinations of uterine biopsy specimens provide more detailed information than microbiological examinations of uterine swabs. Uterine content and uterus biopsy specimens of 55 mares were examined histologically on days 3, 6 and 9 post partum. We observed a heavy polymorphonuclear reaction of the endometrium following disturbed puerperal processes especially in cases of retained placenta. This reaction of the endometrium as well as a delayed regeneration of the uterine epithelium and the uterine gland epithelium resulted in significantly lower fertility rates at the first post partum oestrus. In such cases the foal heat should therefore not be used for breeding.