Nagy P, Huszenicza G, Juhász J, Kulcsár M, Solti L, Reiczigel J, Abaváry K
Department of Obstetrics and Reproduction, University of Veterinary Science, Budapest, Hungary.
Theriogenology. 1998 Nov;50(7):1109-19. doi: 10.1016/s0093-691x(98)00212-x.
Management of the postpartum period is one of the most important factors of stud farm medicine. In horses, owing to the long gestation period, the time from parturition to repeat conception needs be short to maintain an optimal yearly foaling interval. For this reason the features of postpartum ovarian activity and sexual behavior were studied under farm conditions. During 2 consecutive breeding seasons, 107 mares on 5 commercial horse farms were monitored after parturition by regular teasing, transrectal ultrasonography and blood sampling for progesterone. Foalings took place from January 1 to June 15. Body condition scoring was carried out within 5 d and at 60 to 65 d after parturition. The first ovulation occurred within 20 d after foaling in 84.1% (90/107) of the mares. The mean intervals from foaling to the first and second ovulations were 17.8 +/- 1.6 d (+/- SEM) and 40.9 +/- 2.7 d (+/- SEM), respectively. The mean intervals from parturition to the first and second ovulation (P < 0.001), the interovulatory interval (P < 0.01), the second follicular phase (P < 0.001), and the time until the first overt estrus (P < 0.01) were significantly longer in mares foaling before the vernal equinox. In the beginning of the breeding season the intervals from parturition to the first ovulation (P < 0.01), to the second ovulation (P < 0.01), and to the first overt estrus (P < 0.001) were significantly longer for primiparous mares than for multiparous animals. There was a tendency for an increased interovulatory interval and for a longer second follicular phase in mares with decreased body condition after parturition (P = 0.069, P = 0.089, respectively). Suckling and breed had no effect on postpartum ovarian activity. We concluded that under field conditions the resumption of cyclic ovarian activity and sexual behavior in mares after foaling are strongly affected by the season of parturition and parity. In some cases, body condition change and other factors may also play a role in influencing postpartum reproductive function.
产后阶段的管理是种马场医学最重要的因素之一。在马匹中，由于妊娠期长，从分娩到再次受孕的时间需要很短，以维持最佳的年度产驹间隔。因此，在农场条件下研究了产后卵巢活动和性行为的特征。在连续两个繁殖季节，对5个商业种马场的107匹母马在分娩后通过定期试情、经直肠超声检查和采集血液检测孕酮进行监测。产驹时间为1月1日至6月15日。在分娩后5天内以及分娩后60至65天进行体况评分。84.1%（90/107）的母马在产后20天内首次排卵。从分娩到第一次和第二次排卵的平均间隔分别为17.8±1.6天（±标准误）和40.9±2.7天（±标准误）。在春分前产驹的母马，从分娩到第一次和第二次排卵的平均间隔（P<0.001）、排卵间期（P<0.01）、第二个卵泡期（P<0.001）以及到第一次明显发情的时间（P<0.01）显著更长。在繁殖季节开始时，初产母马从分娩到第一次排卵（P<0.01）、到第二次排卵（P<0.01）以及到第一次明显发情（P<0.001）的间隔比经产母马显著更长。分娩后体况下降的母马有排卵间期延长和第二个卵泡期延长的趋势（分别为P = 0.069，P = 0.089）。哺乳和品种对产后卵巢活动没有影响。我们得出结论，在野外条件下，母马产后周期性卵巢活动和性行为的恢复受分娩季节和胎次的强烈影响。在某些情况下，体况变化和其他因素也可能在影响产后生殖功能方面发挥作用。
