Factors That Influence in vivo Production of Goat Pronuclear-stage Embryo

The objective of this study was to improve the efficiency of pronuclear-stage embryo yield to be used forDNA microinjection in a transgenesis goat program. A total of 107 goats with different body weight and different breeds in Shangdong porvince were selected as donors(1 ~5 years old)for superovulation and pronuclear embryo collection using different superovulation programs, sexual mating and embryo flushing in spring and winter. The results showed that the efficiency of pronuclear-stage embryo yields between Jia Xiang and Yi Shui goat breeds was similar. The average numer of embryos recovered per goat with over 40 kg body weight was significantly higher than that of with30 ~40 kg body weight(P 0.05). When the donor's surgery number was over 3 times, the number of available embryos decreased and came to the bottom at 5~6 times surgery with significant difference(P0.05). There was no significnta difference between spring and autumn in the average number of recovered embryos, of embryos used for transfer and the pregnancy rate of goats(P 0.05). The average number of pronuclear-stage embryos availabe for transfer was higher using the FSH-8-injection slowing reduction than FSH-8-injection reduction. The data demonstrated that the efficiency of pronuclear-stage embryo yield could be improved when the goats with more than50 kg body weight and less than 3-times surgery were selected.