The objective of this study was to investigate the relationship between body weight, body condition score (BCS), blood urea nitrogen (BUN), glucose, cholesterol and number of transferable embryos for the purpose of improving reproductive performance in Hanwoo donors. Seventy five cows, at random stages of the estrous cycle, received a CIDR together with injection of 1mg estradiol benzoate and 50 mg progesterone, and gonadotropin treatment begann. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU = 1 ml) administered twice daily in constant doses over 4 days. On the 3rd administration of FSH, CIDR was withdrawn and 25 mg was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received GnRH at the time of 1st insemination. Embryos were recovered 7 days after the 1st insemination. In conclusion, cows with body weight < 400, 400~450 and > 450kg had number of transferable embryos of , and , cows with BCS <2.25, 2.25~2.75 and had number of transferable embryos of , and respectively. These data indicate that a body weight and BCS for superovulation of CIDR-treated Korean native cows does not affect the embryo yield.

The objective of this study was to investigate the relationship between estrous expression, body condition score (BCS), blood urea nitrogen (BUN) and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Sixty, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 μg GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. The estrous inducement rate and estrous expression rate were significantly lower for cows with BCS below 2.25 than for cows with BCS above 2.25. There was 50.0% of rate of mounting in cows with BCS below 2.25 whereas the rate of mounting was markedly increased in cows with BCS above 2.25 (94.1% and 89.5% for BCS 2.25～2.75 and BCS above 2.75 cows, respectively). Cows with BCS ＜2.25, 2.25～2.75 and ≥2.75 had number of transferable embryos of 4.5±0.7, 5.9±1.8 and 5.6±2.3 respectively.

The objective of this study was to investigate the relationship between concentration of urea nitrogen, glucose, cholesterol and number of transferable embryos for the purpose of improving reproductive performance in blood of Hanwoo donors. Fifty five, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100μg GnRH at the time of 1nd insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had number of transferable embryos of 4.3±1.3, 5.8±1.8 and 4.7±2.1 respectively. The mean numbers of total ova from < 10 and 10≤ of corpora lutea(CL) was 8.9 and 14.3, respectively. The number of transferable embryos differed between < 10 and 10≤ CL was 4.8 and 5.6, respectively.

The objective of this study was investigate the superovulation treatment and to relate concentrations of blood urea nitrogen(BUN) in Hanwoo donors. Thirty six, at random stages of the estrous cycle, received a CIDR. Four days later, the animals were superovulated with a total of 28AU FSH (Antorin, 2AU=1 ml) administered twice daily in constant doses over 4 days. On the 3th administration of FSH, CIDR was withdrawn and 25 mg PGF2α was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received 100 μg GnRH at the time of 1st insemination. Embryos were recovered 7 or 8 days after the 1st insemination. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had return of estrus of 34.6, 30.5 and 30.4 days respectively. Return of estrus after superovulation treatment was not significantly lower for cows with blood urea nitrogen (BUN) above 10 mg/dl than for cows with BUN below 10 mg/dl. Cows with BUN ＜10, 11～18 and ≥19 mg/dl had number of transferable embryos of 3.2±1.2, 5.4±1.9 and 4.1±2.1 respectively.

The purpose of this study was to determine the effect of different feeding ratios of whole crop barley silage on the embryo production in Hanwoo donors. All donors were basically fed 2.5 kg concentrate daily. Donors were divided into three groups according to the different feeding of forage; hay 70% and rice straw 30% (control, n = 21), whole crop barley silage 80% and rice straw 20% (T1, n = 25), and whole crop barley silage 60% and rice straw 40% (T2, n = 23) fed based on TDN 6.70/ BW 500 kg. All Hanwoo donors received a CIDR together with injections of 1 mg estradiol benzoate and 50 mg progesterone (, Day 0). Four days later, they were superovulated with 28 mg FSH twice daily IM in decreasing doses over 4 days. Then donors received 2 doses of (25 and 15 mg) with the 5th and 6th injections of FSH on Day 6. CIDR were withdrawn at the 6th FSH injection and the donors received GnRH 36 h after the second injection. The donors were artificially inseminated twice, at 8 and 24 h after GnRH, and embryos were recovered 7 or 8 days after the 1st insemination. The flush rate of the donors following positive superovulation responses did not differ among groups (76.2~96.0%, p>0.05). The number of corpus luteum (CL) at embryo recovery also did not differ among groups (10.6~14.0, p>0.05). Furthermore, the mean numbers of total ova (9.4, 10.5 and 12.0) and transferable embryos (5.3, 12.0 and 6.5) did not significantly differ among the control, T1 and T2 groups, respectively (p>0.05). However, mean concentrations of serum of the T1 (64.2 ng/ml) and T2 groups (55.7 ng/ml) were higher than that of control group (43.3 ng/ml, p<0.01), while serum cholesterol concentrations in the control (105.8 mg/dl) and T2 groups () were significantly lower than in the T1 group (121.1 mg/dl, p<0.05). Conclusively, whole crop barley silage can be fed a good substitute for hay forage for Hanwoo donors. Furthermore the ratios of whole crop barley silage 60% and rice straw 40% might be more worthful for embryo production.

본 연구는 MOET 기법에 의해 우수한 한우로부터 다수의 수정란을 회수하여 농가의 소에 이식하므로서 우수한 유전 자원을 확산시키고자 실시하였다. 80두의 우수 한우 공란우를 선발하여, 발정 확인 후 황체기에 성선 자극 호르몬()을 투여하는 기존의 과배란 처리법과 임의의 발정주기에 CIDR를 삽입하고 성선 자극 호르몬을 투여하는 새로운 과배란 처리법에 의한 수정란 생산 비교와 CIDR 삽입한 한우 공란우에서 성선 자극 호르몬 ()의 투여 용량의 차이 (3