性控精液对奶牛体内胚胎质量、发育和移植妊娠率的影响

Effects of Sex-sorted Semen on In Vivo Embryo Quality,Development and Pregnancy Rate of Embryo Transfer in Dairy Heifers

[目的]研究性控精液对奶牛体内胚胎质量、胚胎发育和胚胎移植妊娠率的影响。[方法]将144头青年奶牛随机分为对照组(63头)和试验组(81头),使用促卵泡激素(FSH,260 mg/头)进行超排处理。对照组和试验组分别使用常规精液和性控精液输精,并对获得的体内性控胚胎进行移植,对胚胎生产、胚胎质量、胚胎发育和胚胎移植妊娠情况进行统计。[结果]试验组供体获得的平均可用胚胎数(5.67枚)显著(P<0.05)低于对照组(6.92枚);试验组供体获得的可用胚胎中A级胚胎比例(62.53%)、B级胚胎比例(35.29%)与对照组(A级胚胎比例66.51%、B级胚胎比例30.97%)相比差异均不显著(P>0.05);试验组供体获得的可用胚胎中桑葚胚比例(84.10%)显著(P<0.05)高于对照组(61.24%),囊胚比例(15.90%)显著(P<0.05)低于对照组(38.76%);试验组的鲜胚移植妊娠率(52.41%)显著(P<0.05)低于对照组(66.13%)。[结论]与常规精液相比,使用性控精液生产奶牛体内性控胚胎并移植后,平均可用胚胎数、可用胚胎中囊胚比例和胚胎移植妊娠率降低,可用胚胎质量未明显降低;优化性控精液使用方案和胚胎移植技术能够提高体内性控胚胎生产和胚胎移植效率。

[Objective]The present study aimed to assess the effects of sex-sorted semen on quality and development of embryo in vivo as well as on the pregnancy rate of embryo transfer in dairy heifers.[Method]A total of 144 dairy heifers served as donors were randomly assigned into a control group(n=63)or an experimental group(n=81).Follicle stimulating hormone(FSH)was used for superovulation treatment at dosage of 260 mg per heifer.The dairy heifers in the control group and the experimental group were artificially inseminated with normal and sex-sorted semen,respectively.The obtained fresh in vivo-derived sex-sorted embryos were transferred into the recipients.The embryo production,embryo quality,embryo development,and pregnancy rate of embryo transfer were statistically recorded.[Result]The mean number of transferable embryos obtained from the donors in the experimental group(5.67)was significantly(P<0.05)lower than that in the control group(6.92).The proportions of Agrade embryos(62.53%)and B-grade embryos(35.29%)in the transferable embryos obtained from the donors in the experimental group did not significantly(P>0.05)differ from those in the control group(66.51% of A-grade embryos and 30.97% of B-grade embryos).The donors in the experimental group had a significantly(P<0.05)higher proportion of morula(84.10%)in the transferable embryos in comparison to the control group(61.24%),while had a significantly(P<0.05)lower proportion of blastocyst(15.90%)compared with the control group(38.76%).The pregnancy rate of fresh embryo transfer in the experimental group(52.41%)was significantly(P<0.05)lower than that in the control group(66.13%).[Conclusion]Compared with the use of normal semen and embryo,the use of sex-sorted semen lowered the mean number of transferable embryos and the proportion of blastocyst in the transferable embryos of the donors,and that of sex-sorted embryo decreased the pregnancy rate of the recipients.However,the quality of transferable embryos had no significant reduction.Optimizing the use of sex-sorted semen and the embryo transfer technique can improve the efficiencies of in vivo sex-sorted embryo production and embryo transfer.