奶牛性控与常规冻精DNA损伤的彗星检测

本文为确定性控冻精与常规冻精的DNA损伤程度,利用彗星实验法分别将奶牛的性控冻精和常规冻精凝胶混合液在裂解液中作用后,使用普通载玻片双层铺胶,电泳,吖啶橙染色后在荧光显微镜下检测、拍照,经CASP软件图像分析后用SPSS 11.5进行数据统计,初步建立了奶牛精子DNA损伤的5级彗星图谱。统计结果显示,性控冻精的DNA损伤系数为116,显著高于常规冻精的损伤系数（28）（P〈0.01）;彗星率为63.06%,显著高于常规冻精的彗星率（31.13%）（P〈0.01）。可以得出,性控冻精DNA损伤显著高于常规冻精。

Comet Assay for Determining the Integrity of DNA between Frozen-sexed and Frozen Sperm in Dairy Cow

To determine the integrity of DNA between frozen-sexed and frozen sperm in dairy cow,comet assay was conducted in this study.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,stained with acridine orange and photographed at a microscope.All data were analysed by the CASP and SPSS software.Sperm DNA comet figures for dairy cow were established.Damage coefficient was 116 and 28 for the frozen-sexed and sexed sperm samples respectively,the frozen-sexed sperm damage coefficient was significantly higher than frozen sperm（P0.01）.There was significant difference in the percent of comet rate intact between the frozen-sexed and sexed sperm（63.06% vs.31.13%;P0.01）.In a conclusion,the frozen-sexed sperm had more DNA damages than frozen sperm.