Abstract
The present study was carried out to investigate the effects of different donor cell types (in vivo-fresh, cloning, recloning, in vivo-frozen or in vitro embryos by ultrasound guided transvaginal aspiration) on development into compacted morulae and pregnancy rates of reconstituted embryos by nuclear transfer. The fusion rate of in vivo frozen donor cells and resipient oocytes (82%) was significantly (P<0.05) lower than in the other donor cells (92-96%). The mean number of compacted morulae dirived from a in vivo-fresh embryo (9.0) was significantly (P<0.05) higher than in the other donor cells. Two of 13 recipient that received the reconstituted embryos dirived from recloning donor cells. However, this pregnancy rate (15%) was significantly (p-0.05) lower than those of the other groups (50-56%).
