본 연구는 1997년 IMF 이후 급격히 감소된 한우의 두수를 증가시키고, 최근 젖소 송아지 가격이 현저히 낮게 형성되고 있어 양축가의 사기가 떨어지고 있는데 가임 젖소 암소에 한우 수정란을 이식시켜 한우 송아지를 생산케 함으로서 농가 소득을 증대시키고 실시하였다. 1. 체외수정 후 6, 7, 8 및 9일째의 수정란을 이식하여 59.4%, 68.2%, 66.0% 및 100%의 수태율을 나타냈으며, 상실배기(20.0%) 수정란이 배반포기(61.1%∼69.
These studies were carried out to improve the reproductive efficiency through embryos transfer of Hanwoo IVM/IVF embryos. Following routine IVM/IVF procedure, oocytes and zygotes were cultured far 40 to 44 h in CRlaa medium with BSA. Then 2 to 8-cell embryos were removed the cumulus cell and were cultured in CRlaa medium containing 10% fatal bovine serum and 2.5 mM taurine in 5% and 5% at 38.5. The fresh embryos of the morulae and blastocysts cultured for 6 to 9 days in vitro or the frozen-thawed embryos were transferred into recipients. The pregnancy rates of the blastocyst produced for 6, 7, 8, and 9 days in vitro culture were 59.4, 68.2, 66.0 and 100%, respectively. In the developmental stage, pregnacy rates of early blastocysts (61.1%), blastocysts(64.7%) and expanded blastocysts(69.5%) were higher than that of morulae stage(20.0%). The pregnancy rates according to the corpus luteum grades of A, B and C in recipients were 73.6, 62.9 and 50.0%, respectively. Effects of donor-recipients synchrony of after day 2, 1 and 0, before day 1 and 2 on the pregnancy rates were 35.7, 65.5, 72.6, 67.9 and 60.0%, respectively. Pregnancy rates of the body condition score of recipients 2(71.3%) were higher than those of 3.0 score(40.0%). The pregnancy rates according to the parity of recipients when embryo was transferred to cow(70.6%) was higher than in heifer(59.1%). The pregnancy rates according to hormone treatment before embryo transfer were 69.9% in hCG + GnRH administration group and 63.0% in control group. Fresh and frozen-thawed embryos on the pregnancy rates were 70.6 and 36.4%, respectively. Pregnancy rates in single and AI+single was 90.0% and 64.8%. Pregnancy rates in twin induction was better than in single. These results indicate that pregnancy rates after transfer were affected on the embryo ages, donor-recipient synchrony, body condition score of recipients, corpus luteum status, parity and hormone treatment to recipients.