影响马胚胎移植成功率的关键因素分析

旨在探讨影响马胚胎移植效率的几种关键因素。本研究统计了国内北京马场、河北马场和山东马场2013-2018年胚胎移植数据，3个马场供体马数量分别为15、21和25匹，受体母马数量分别为56、50和75匹。所有母马年龄为3~12岁。统计供体马冲胚时间对胚胎回收率的影响；胚胎日龄对移植后受体马妊娠率的影响；供、受体母马排卵同期化程度对移植后妊娠率的影响；受体母马居住移植基地时间对移植后妊娠率的影响。结果显示，母马在配种季节注射前列腺素（PG）+GnRH类似物或PG+hCG诱发排卵，发情周期分别为（14.5±0.8）和（14.3±1.1）d，显著低于对照组的（（20.5±2.6）d，P<0.05）；排卵后第8天冲洗子宫的胚胎回收率均高于第7天，但差异不显著；8日龄胚胎移植后受体马的妊娠率均高于7日龄，差异不显著；供体母马排卵比受体母马早1 d时，胚胎移植后的妊娠率最高；受体母马在移植基地居住时间大于1年时，移植后妊娠率高于居住时间小于0.5年的受体马。根据以上结果，本研究得出如下结论，PG与hCG或GnRH类似物联合使用可缩短母马发情周期，母马排卵后第8天的胚胎回收率和移植后妊娠率较高，胚胎移植时选择居住时间大于1年且排卵时间比供体晚1 d的母马作受体。

The Analysis of Key Factors Affecting the Success Rate of Equine Embryo Transfer

This study aimed to research factors affecting the efficiency of equine embryo transfer. The data of embryo transfer in 3 horse farms from 2013 to 2018 were analyzed.The number of donor horses in the 3 farms were 15, 21 and 25, respectively, and the number of recipient mares were 56, 50 and 75 respectively. All mares were 3 to 12 years old. The following items were counted:The effect of flushing day post ovulation of donor horses on the embryo recovery rate; The effect of embryonic age on the pregnancy rate of recipient mares after transplantation; The effect of the degree of ovulation synchronization of the donor and recipient mares on the pregnancy rate after transplantation; The effect of residence time at farm of recipient mares on pregnancy rate after transplantation. The results indicated that, mares were injected with prostaglandin (PG)+GnRH analogues or PG + hCG to induce ovulation during the breeding season, the estrous cycle were (14.5±0.8) and (14.3±1.1)d, respectively, which was significantly lower than the control group ((20.5±2.6) d, P<0.05). The embryo recovery rate of washing the uterus on the 8th day after ovulation was higher than that on the 7th day, but the difference was not significant; The pregnancy rate of recipient horses after 8-day-old embryo transfer was higher than that of 7-day-old, and the difference was not significant; After embryo tranfer, the recipients which ovulated 1 day later than donors had the highest pregnancy rate. When the residence time at farm of recipients was longer than 1 year, the pregnancy rate was significantly higher than those shorter than 0.5 year. In conclusion, the injection of PG + hCG or PG + GnRH anologue could shorten estrus cycle of mares. The embryo recovery rate and the pregnancy rate after transplantation of the 8th day embryo after ovulation were higher. When the embryos were transplanted, the mares with the residence time at farm more than 1 year and the ovulation time 1 day later than the donors were used as recipients.