奶牛卵胞质内单精注射(ICSI)的研究

Studies on Intracytoplasmic Sperm Injection(ICSI) in Cow

[目的]探讨不同状态奶牛精子卵胞质内单精注射(ICSI)的效果。[方法]体外成熟培养24 h的奶牛卵母细胞注入不同状态精子,观察其体外发育情况。[结果]结果表明,试验1,研究精子用5 mmol DTT(二硫苏糖醇)预处理与精子不经过预处理的对照组的效果,经DTT处理后,精子解聚率和雄原核率显著高于对照组(30.4%和11.6%,47.8%和27.9%,P<0.05),两组的卵裂率差异不显著(85.0%和80.0%),囊胚率和孵化率显著高于对照组(45.8%和26.0%,31.3%和14.0%,P<0.05)。试验2,比较死、活精子的卵胞质内单精注射的效果,两者之间卵裂率(75.0%和79.4%)、囊胚率(27.9%和30.9%)和孵化率(13.2%和16.2%)均无显著性差异(P>0.05)。试验3,比较睾丸或附睾(头、体、尾)精子卵胞质内单精注射的效果,卵裂率(79.1%、81.8%、73.2%和75.0%)、囊胚率(23.3%、20.4%、19.5%和18.2%)和孵化率(14.0%、13.4%、12.2%和9.1%)均无显著性差异(P>0.05)。[结论]DTT预处理奶牛精子有助于提高ICSI的效率;死精子能用于奶牛卵母细胞的ICSI;从睾丸精子到附睾尾精子,虽其成熟程度有很大不同,但对ICSI受精不产生显著影响。

[ Objective ] This study aimed to evaluate sperm of different states affecting ICSI so as to improve the efficiency of ICSI in cow. [ Method] Cow oocytes were collected from slaughterhouse ovaries and matured in vitro for 24 h. Sperm of different states was injected into an oocytes by assistance of a micromanipulation system. Development of injected oocytes was examined. [ Result ] The results indicated that the development of oocytes with the DTr-treated group and the non-treated group were compared in experiment 1. Significantly higher rate of sperm decondensation and male pronuclear rate were found in the DTT-treated group than the non-treated group （30.4% and 11.6% ,47.8% and 27.9% , P 〈0.05, respectively）. There was no significant difference with cleavage between two groups（85.0% and 80.0% ）, significantly higher blastocyst and hatched blastocyst rates were found in the DTT-treated group than the non-treated group（45.8% and 26.0%, 31.3% and 14.0%, P 〈0.05, respectively）. The development of oocytes injected with dead or lived sperm were compared in experiment 2, No significant difference was found in cleavage, blastocyst and hatched blastocyst（75.0% and 79.4%, 27.9% and 30.9%, 13.2% and 16.2%, P 〉 0.05, respectively）. In experiment 3, No significant difference was found in cleavage, blastocyst and hatched rates between testicular sperm and epididyma sperm （caput,corpus, cauda） （79. 1%, 81.8%, 73.2% and 75.0% ; 23.3%, 20.4%, 19.5% and 18.2% ; 14.0% , 13.4%, 12.2% and 9.1%, P 〉0.05 ,respectively）. [ Conclusions] Efficiency of ICSI in cow can be improved by sperm pretreatment with DTr. Dead sperms can be used for ICSI in cow. Althouth their maturity is different from testicular sperm to epididyma sperm, significant affecting on the fertility and development of ICSI was not found.