The Effect Of Mature Time And Enucleating Condition On Goat Somatic Nuclear Transfer

In order to find an effective nuclear transfer program, this thesis investigated three factors affecting the efficiency of somatic nuclear transfer on goats: the in vivo mature time of oocytes, the component of operation liquid for oocyctes enucleating and the parthenoactivation mode of oocytes.1. Goat oocytes differently matured in vivo 18 h, 22 h and 26 h and the maturing rates were not remarkable. Then these 3 kinds of oocytes were enucleated, the result showed enucleating rates declined as maturing time prolonged. These were 87.1%, 84.4% and 76.5%, respectively. After nuclear transferring, we observed the cleavage rates and the blastula rates of nuclear-transfer embryos. The cleavage rate of embryos corresponding 18 h (71.8%) was obviously lower than ones 22 h (81.1%) and 26 h (82.5%). The blastocyst rate corresponding 22 h (19.6%) was remarkable higher than 18 h (12.5%) and 26 h (15.7%).The conclusion is that the suitable time of oocyte maturation in vivo is about 22 h.2. Putting oocysts with first polarbody into operation liquid which containing cytochalasin-B (CCB), 5 mg/L, 7.5 mg/L, 10 mg/L and15 mg/L ,respectively. After blind enucleating, we detected enucleating rates by fluorescent staining and then constructed recombinant embryos, observing their developmental capacity. Adding sucrose, whose mass concentration was 2%, 2.5% and 3%, respectively, to the operation liquid containing 7.5 mg/L CCB and after enucleating, we detected enucleating rates in the same way and then constructed recombinant embryos, observing their developmental capacity. The result was that achievement ratio of enucleating in operation liquid with 7.5 mg/L CCB (84.4%) was remarkable higher than control group(70.7%) and other groups. Average operating time decreased as CCB concentration increasing. The cleavage ratios of recombinant embryos constructed from oocytes enucleated in operation liquid with 7.5 mg/L and 5 mg/L CCB were 81.1% and 82.4% respectively, remarkable higher than control group(69.8%) and 15 mg/L CCB group(71.8%). The blastocyst ratios of recombinant embryos constructed from oocytes enucleated in operation liquid with 7.5 mg/L...