Studies On The Factors Influencing The Effects Of Embryo Transfer In Boer Goat

To study the factors influencing the effects of embryo transfer in Boer goats, to establish a successful program and to improve the efficacy of embryo transfer in Boer goats, the Boer goat, Xuhuai white goat, Guanzhong dairy goat and Yangzhong indigenous goat does of Jiangsu province were used either as donors or recipients animals in a superovulation, estrus synchronization and embryo transfer program. 1 Studies on the factors influencing effects of superovulation in Boer goatOne of the factors influencing effects of superovulation in Boer goat, the time of superovulation in estrus cycle, superovulation program, different FSH, ovulating hormone, weight and age of donor, season of superovulation, dose of FSH and repeated superovulation were studied in this trial. The correlation of response to superovulation between left and right ovary was also compared. The results were as follows:It is a better result that the mean number of viable embryo was 11.50~18.91 when donors were superovulated from the day of 12th to 17 in estrus period. The program had significantly affected the superovulation effects (P <0.05)and the donors synchronized with one dose of PGF20 could give the most of viable embryos(mean of 18.80). The origin of FSH, weight of donor, season of superovulation did not affect the superovulation results significantly(P>0.05). It was better to stimulate ovulation with LHRH-Aa when donors were mated firstly. The number of viable embryos in parous goats was significantly more than nulliparous gbats(P < 0.05). The dose of FSH had a significant effect on superovulation(.P <0.05). The more of the FSH, the more of the number of CL and viable embryo in parous and nulliparous donors respectively(P <0.05). The more of the superovulation times, the worse of the superovulation effect(.P>0.05). The number of viable embryos did not increase when the interval of mate was decreased. Donors that had the interval from the treatment of PGF2a to estrus of 37~48h had the best superovulation result in viable embryos (mean of 16.50). But donors that showed abnormal estrus had aworse result than that of donors superovulated repeatedly(P >0.05). The response to superovlation and mean recovery rate was not significantly different between the two varies or oviducts (P >0.05).2 Studies on factors influencing the synchronization of donor and recipientThe factors of FSH and method of synchronization influencing the degree of synchronization between donors and recipients were studied in this trial. The results were as follows:The interval from the treatment of PGF20 to estrus was significantly influenced by FSH(P < 0.05). The interval from the treatment of PGF2a to estrus of donors (51.11%~61.11%) treated with FSH was 12h shorter than the recipients without treatment of FSH. The estrus of recipients were significantly different between the different method of synchronization^ <0.05). The interval from the cessation of CIDR treatment to estrus in recipients(58.94%) synchronized with CIDR was 24h earlier than the recipients synchronized with PGF2.3 Effect of recipients on embryo transferIn Xuhuai white goats, Guanzhong dairy goats and Yangzhong indigenous goats, the relationship of recipients pregnant rate and degree of synchronization of estrus in donor and recipient, number of CL, breed, estrus condition of recipients were studied in the trial. Results showed that the higher of the degree of synchronization of estrus in donors and recipients, the higher of the pregnancy rate(P <0.05). The highest pregnancy rate(79.88%) was achieved by the recipients that were in heat 1-12h earlier than donors. The pregnancy rate was not significantly different when the recipients had an induced estrus after abortion and a normal induced estrus(P>0.05). There was no significant difference between the recipients with different number of CL in ovary^ >0.05) and there was a trend that the pregnancy rate decreased when the number of CL increased. Among the three breed of recipients, Xuhuai white goats and Guanzhong dairy goats were better to b...