Detection Of DNA Damage And EarLy Growth Of Offspring On Holsteins Sexed Sperm

To determine the integrity of DNA between frozen-sexed and frozen sperm using comet assay andTUNEL in dairy cow, and then research on the Effects of sex-sorted semen in Holsteins by evalulate thehealth conditions of sexed offspring to make sure whether the sex-sorted sperm can be normal developed.1. Frozen-sexed and frozen sperm were mixed with agarose separately, cultured in the lysis solution.Electrophoresis was conducted on the surface of common glass with two-layer agarose by the conditions of15V,150mA,4℃, stained with acridine orange and photographed at a microscope. All data were analysedby the CASP and SPSS Software. Sperm DNA comet figures for dairy cow were established and the resultshows that the damage coefficient was116and28for the frozen-sexed and sexed sperm samplesrespectively, the frozen-sexed sperm was significantly higher damage coefficient than frozen sperm(P<0.01); There was significant difference in the percent of comet rate intact between the frozen-sexed andsexed sperm (63.06%vs.31.13%; P<0.01).2. To determine the integrity of DNA between frozen-sexed and frozen sperm by TUNEL.The resultshows that there was significant difference in the rate of DNA damage between the frozen-sexed and sexedsperm((31.67±1.03)%,(63.32±0.56)%, P<0.01)3. Eight hundred Holstein heifers were divided into two groups (sexing group, n=400；conventionalgroup, n=400).They were artificially inseminated with sex-sorted semen or conventional, respectively. Theresult shows that the conception rate was67.3%after inseminating with sexing semen. The live birth ratewas84.2%, the pregnancy days was275.8±4.4, the rate of female was88.5%, and the average birthweight of female was37.0±4.48kg (n=295).The rate of conception changed into77.5%after inseminatedwith conventional semen, the live birth rate was90%, the pregnancy days was276.5±6.8, and the averagebirth weight was37.5±4.37kg (n=180). The female ratio by using flow-sexing semen was significanthigher than that using of conventional (P<0.05), and the rest indicators shows no remarkable difference.