[Fertility in mares after disturbed or undisturbed puerperium; evidence from clinical, microbiologic and hormone analysis].

Because of the mare's ability to conceive very soon post partum a thoroughly performed control of the puerperal period is of particular importance. In addition to cytological and histological examinations of the uterus, rectal palpation and vaginoscopic inspection as well as microbiological examinations of uterine swabs and the evaluation of the mare's hormonal status during the puerperal period provide useful information which can be used either prognostically or to initiate a specific therapy. 55 mares were examined on days 3, 6 and 9 post partum. Rectal palpation, vaginoscopic inspection, microbiological examination of uterine swabs and determination of progesterone-(P4)- and estradiol-(E2)-levels in the peripheral blood were performed on all the three days. On day 18 after the last breeding the mares were checked for pregnancy by ultrasonic echography. We observed many cases of heavy bacterial contamination of the uterine contents during the puerperal period up to the foal heat. Especially coliforms and beta-hemolytic streptococci were often found. However, these contaminations could not be proven to interfere with fertility rates during the first post partum estrus periods. Dystocia and retained placenta had a strong influence on the hormonal situation of mares during the puerperal period. In addition to this we found disturbed involution of the genital system in these mares. Much higher pregnancy rates at foal heat were detected after a rapid onset of ovarian activity post partum especially during May, June and July, compared to mares with delayed onset of ovarian activity.(ABSTRACT TRUNCATED AT 250 WORDS)