Abstract： To optimize the protocols of nuclear transfer, effects of cytochalasin-B(CB) treatment and cytoplasm removal on parthenogenetic embryos of goat were observed. MetaphaseⅡ(MⅡ)stage goat oocytes were treated with 7.5 μg/mL CB for 5、10、15、20 and 30 min, respectively (groupⅠ), removal of cytoplasm from 1/4 to 1/2(group Ⅱ)and with nothing(control). Differential staining of inner cell mass (ICM) and trophectoderm (TE) cells of blastocysts (Day 5~7) was performed with propidium iodide and Hoechst 33258, and the numbers of ICM and TE cells were recorded respectively. The groupⅠand control showed higher cleavage rate(83%~ 85.50%,86.50%)and blastocyst rate(57.40%~62.20%,59.80%)than that of group Ⅱ, the numbers of total cells and ratio of ICM cells had no significantly difference between various groups(P＞0.05). However, the cleavage rate(75.76%~16.07%), blastocyst rate(38.67%~6.67%), numbers of total cells(107.15~63.67)and the ratio of ICM cells(26.32%~19.37%)decreased with increasing removal proportion of cytoplasm, and embryonic developmental ability significantly decreased when the removal proportion went beyond 1/3. These results suggest that(1)The treatment of 7.5 μg/mL CB for 30 min has no significant effect on oocyte development of goat embryo in vitro;(2)The volume of removal of cytoplasm under 1/3 has no significant effect on development of goat embryo in vitro.
