胚胎质量和发育阶段对奶牛胚胎移植妊娠率的影响

Effect of Embryo Quality and Development Stages on Pregnancy Rate of Cow Embryo Transfer

[目的]为了评估胚胎质量和发育阶段对奶牛胚胎移植妊娠率的影响。[方法]使用63头青年奶牛作为供体进行超数排卵,评估回收胚胎质量和发育阶段。选择334头青年奶牛作为受体鲜胚移植不同质量和发育阶段胚胎。对胚胎质量分布、发育阶段分布、不同质量胚胎和不同发育阶段胚胎移植30 d妊娠率进行统计分析。[结果]可用胚胎中A级胚胎比例(60.78%)显著高于B级和C级胚胎比例(36.70%和2.52%)(P<0.05);致密桑椹胚比例(54.36%)显著高于早期囊胚,囊胚和扩张囊胚比例(18.35%,25.0%和2.29%)(P<0.05)。A级和B级胚胎移植30 d妊娠率(63.55%和64.35%)显著高于C级胚胎移植30 d妊娠率(44.44%)(P<0.05);致密桑椹胚、早期囊胚、囊胚和扩张囊胚移植30 d妊娠率差异不显著(P<0.05),早期囊胚、囊胚移植30 d妊娠率高于致密桑椹胚、扩张囊胚移植30 d妊娠率(P<0.05)。[结论]选择不同发育阶段的A级和B级胚胎能够获得较高胚胎移植妊娠率,增加早期囊胚和囊胚阶段胚胎移植数量能够提高胚胎移植妊娠率。

[Objective]To evaluate the effect of embryo quality and developmental stages on the pregnancy rate of embryo transfer in recipients.[Method]63 dairy heifers were superovulated and the quality and developmental stages of collected embryos were evaluated.334 heifers were selected as recipients for fresh embryo transfer of embryos of different quality and developmental stages.Statistical analysis was conducted on the distribution of embryo quality,developmental stage distribution,and 30 day pregnancy rate of embryo transfer at different quality and developmental stages.[Result][Result]The proportion of A-grade embryos(60.78%)in available embryos was significantly higher than that of B-grade and C-grade embryos(36.70%and 2.52%)(P<0.05).The proportion of compact morula(54.36%)was significantly higher than that of early blastocyst,blastocyst and expanded blastocyst(18.35%,25.0%and 2.29%)(P<0.05).On day 30,the pregnancy rate of grade A and B embryos(63.55%,64.35%)were significantly higher than that of grade C embryos(44.44%)(P<0.05).There were no significant difference in the 30-day pregnancy rate among compact morula,early blastocyst,blastocyst and expanded blastocyst transplantation(60.75%,66.67%,67.86%and 60.00%)(P>0.05).The 30-day pregnancy rate of early blastocyst and expanded blastocyst transplantation was higher than that of dense morula and expanded blastocyst transplantation(P<0.05).[Conclusion]The selection of grade A and B embryos at different embryonic developmental stages can achieve a higher embryo transfer pregnancy rate.Increasing the number of early blastocysts and blastocyst transfers could improve embryo transfer pregnancy rates.