孵育和激活剂作用时间对山羊核移植胚胎早期发育的影响

探讨了电融合前对重构卵继续孵育及激活剂6-DMAP不同作用时间对山羊核移植胚胎体外发育的影响。结果显示,重构卵在成熟液中继续培养后,9~10 h组的融合后卵子死亡率(27.42%)显著低于30 min和90 min组(49.26%和56.3%)(P0.05),胚胎卵裂率(68.15%)则显著高于30 min和90 min组(55.6%和54.24%)(P0.05);重构卵用离子霉素激活后,再用6-DMAP激活0 h、2 h、3 h、4 h、5 h及8~10 h,各组间的胚胎卵裂率均无显著差异(P0.05),但均显著高于未用6-DMAP组的卵裂率(P0.05)。本试验结果表明,电融合前,继续成熟培养重构卵有利于降低电融合时的卵子死亡率,提高卵子利用率;联合使用离子霉素和6-DMAP有利于提高激活效果,而6-DMAP的作用时间(2~10 h)不影响核移植胚胎的卵裂。

Effects of incubation time and activation time of 6-DMAP on the early development of the goat nuclear transplanted embryos

The study was conducted to examine the effects of incubation time before the electrofusion and activation time of 6-DMAP on the development of the goat nuclear transplanted embryos in vitro. The reconstructed oocytes were continually cultured in a maturation medium for 30 min, 90 min and 9-10 h before the electrofusion, respectively. The results showed that the mortality of reconstructed oocytes of 9-10 h group after the electrofusion was significantly lower than those of 30 min and 90 min groups (27.42% vs. 49.26% and 56.3%, P<0.05), while the cleavage rate of 9-10 h group was significantly higher than those of 30 min and 90 min groups (68.15% vs. 55.6% and 54.24%, P<0.05). The nuclear transplanted embryos activated by ionomycin were activated with 6-DMAP for 0 h, 2 h, 3 h, 4 h, 5 h, and 8-10 h respectively. The results showed that the cleavage rate was not significantly different among groups (P>0.05), but it was significantly higher than that of the embryos without 6-DMAP (P<0.05). In conclusion, the continued incubation of reconstructed oocytes before electrofusion may be helpful for lowing the mortality of fusion and increasing the rate of available oocyte; the combination of ionomycin with 6-DMAP could improve the activation efficiency in goat nuclear transplanted embryos, and activation time of 6-DMAP has no significant effects on the cleavage of goat nuclear transplanted embryos.