Study on Factors Affecting Pregnancy Rate of Bovine Sexing Embryo Transfer

In this study,the factors affectting pregnancy rate of bovine sexing embryo transfer were analyzed to improve pregnancy rate.The findings appeared: 1.Compared pregnancy rate of intact embryos with biopsied embryos,no significant differences were found for both fresh and frozen embryos(P0.05).This indicated that biopsied embryos were available in commercial use.2.The pregnancy rate of biopsied embryos tend to decrease with the increase of cell quantity being removed,and the damage led by freezing increased significantly.3.Developmental rate and pregnant rate of embryos outside in vitro within 5h from fluhing to freezing were very obviously higher than that of those embryos more than 5 h from flushing to freezing(P0.01).4.All stages of embyos could get acceptable pregnancy rate when they were transferred to the recipients of 7.5～8.5 days after estrus.5.The pregnancy rate of recipients with high progenitive capacity were very significantly higher than those with low progenitive capacity(P0.01).