Induction of twinning in Korean native cattle by transfer of nuclear transplanted embryos I. Embryo cloning using ovum pick-up(OPU), electric cell fusion and in vitro culture system

핵이식 기법을 이용한 한우 쌍태생산에 관한 연구 I. Ovum pick-up(OPU), 전기적 세포융합 및 체외배양 기법을 이용한 복제수정란 생산

The purpose of present study is to improve the efficiency of fusion and the developmental rates of nuclear transplanted embryos to produce genetically identical twins from Korean native cattle. The diameter of aspirated follicles had no significant effect on the recovery rates of oocytes collected by ovum pick-up technique. The fusion rates of nuclear transplanted embryos were significantly higher in 50 and $100{\mu}s$ DC duration groups(73.3 and 72.0% ; respectively) than that in $30{\mu}s$ group(55.6% ; p<0.05). The cleavage rates of nuclear transplanted embryos appeared to be significantly higher in donor nuclei derived from in vivo (65.0%) than in those from in vitro (50.5% ; p<0.01), but the developmental rates to morulae and blastocysts were not significantly different between them(13.7 vs 10.9%, respectively).