Study On The Effect Of Sexing-sperm In Industrialization Of Dairy Embryo Transfer

It becames possible for determining sex of offsprings pre-fertilization along with development of X and Y sperm sorting technology. This test is designed to study on effect of sexing semen on bovine superovulation and sexing embryo on pregnant rate systemically and discuss the feasibility of application of sexing semen in industrialization of dairy embryo transfer.The effect of sexing sperm on dairy superovulation indicated:1 .The total quantity of and viable embryos obtained mated with routine frozen semen were the remarkable higher than ones with sexing sperm, which were 10.2,6.68 vs 6.85, 3.74 and both of them had a remarkable difference(p<0.01). The rate of available embryos and unfertilized oocytes are 65.5%, 13.9% vs 54.5%, 21.9% respectively, which had a remarkable difference (p<0.01), but the rate of degenerated embryos are 20.6% and 23.6%, which had no significant difference. (p>0.05).2. The study on the different concentration and dosage of sexing semen found that there were no significant difference in the average of embryos collected mated with different concentration of sexing sperm(8.1 vs 6.4), (P>0.05), and got the similar results in the average of total quantity of, viable and degenerated embryos collected mated with 3 or 4 straws(5.94, 2.82, 1.29 vs 7.76, 4.65, 1.94), but there were significant difference in the rate of unfertilized oocytes (30.7% vs 15.2%)collected inseminated with 3 vs 4 straws(p<0.01).3. The average of embryos collected in the group of 11-13h performing insemination post estrous was remarkable higher than that of 15-17h(4.5 vs 8.0)(P<0.05). The group of 13-15h performing insemination post estrous was remarkable higher than that of 1 l-13h(4.67vs 1.83)(P<0.05), but no siginificant difference comparing with 15-17h groups (P<0.05).4. There was a better result by performing sexing semen into each horn of uterus in dairy superovulation,there was no significant difference with different part insemination of uterus in routine semen and sexing semen groups, but the average of unfertilized oocytes was significant difference in sexing semen group (P<0.05).Analysis of effect of sexing embryos on pregnant rate of recipients shows:1. the pregnant rate of sexing fresh embryos was a little higher than that of sexing frozen embryos (51.2% vs 44.4%),but both of them were no siginificant difference(P>0.05). There were no remarkable difference in pregnant rate of regular embryos(51.2%), sexing embryos(46.2%) and sexed embryos(49.0%).2.The rate of delivering offsprings origined from regular embryos,sexing embryos and sexed embryos was 91.2%, 91.8%and 89.9% repectively and no siginificant difference above three types of embryos. The rate of delivering female offsprings origined from sexed embryos is the highest(97.9%) in three groups, but no siginificant difference comparing with sexing embryos(p>0.05), of course, both of two groups as above were higher than regular embryos group(p<0.01).3.The rate of abortion or fetal death origined from regular embryos, sexing embryos and sexed embryos were 8.8%, 8.2% and 10.1%, which no remarkable diffence among them(P>0.05).In summary, the research of superovulation with sexing sperm and pregnancy rate of sexing embryo transfer indicated that sexing semen as part of industrialization of dairy embryo transfer can extension in the future, but need to research further in the protocol of usage of sexing sperm and development of offsprings origined from sexing embryos.