Oxygen consumption is a useful parameter for evaluating mammalian embryo quality, since individual bovine embryos was noninvasively quantified by scanning electrochemical microscopy (SECM). Recently, several approaches have been used to measure the oxygen consumption rates of individual embryos, but relationship between oxygen consumption and pregnancy rates of Hanwoo following embryo transfer has not yet been reported. In this study, we measured to investigate the correlation between oxygen consumption rate and pregnancy rates of Hanwoo embryo using a SECM. In addition to, the expression of pluripotent gene and anti-oxidant enzyme was determined using real-time PCR by extracting RNA according to the oxygen consumption of in vivo embryo. First, we found that the oxygen consumption significantly increased in blastocyst-stage embryos (blastocyst) compared to early blastocyst stage embryos, indicating that oxygen consumption reflects the embryo quality (Grade I). Oxygen consumption of blastocyst was measured using a SECM and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. The oxygen consumption or GI blastocysts were significantly higher than those of GII blastocysts (10.2 × 1015/mols—1 versus 6.4 × 1015/mols—1, p<0.05). Total cell numbers of in vitro blastocysts were 74.8, 90.7 and 110.2 in the oxygen consumption of below 10.0, 10.0∼12.0 and over 12.0∼1015/mols—1, respectively. Pregnant rate in recipient cow was 0, 60 and 80% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0∼12.0 and over 12.0 × 1015/mols—1, respectively. GPX1 and SOD1 were significantly increased in over —10.0 group than below 10.0 groups but in catalase gene, there was no significant difference. On the other hand, In OCT-4 and Sox2, pluripotent gene, there was a significant difference (p<0.05) between the below-10.0 (0.98 ± 0.1) and over 10.0 (1.79 ± 0.2). In conclusion, these results suggest that measurement of oxygen consumption maybe help increase the pregnant rate of Hanwoo embryos.

산소소비량은 수정란이식 수태율에 영향을 미치는 여러 요인들 중 하나인 수정란의 품 질을 판정할 수 있는 기준으로 알려져 왔다. 최 등(2010)은 한우 체내수정란의 형태학적 인 등급에 따른 산소 소비량을 비교, 체외수정란의 산소 소비량과 총세포수의 상관관계 를 확인한 결과, 국제수정란이식학회(International Embryo Transfer Society, IETS)에서 규정하고 있는 수정란의 등급 판정 기준에 준하여 형태학적 등급이 좋을수록 수정란의 산소 소비량도 높아지고, 체외수정란의 산소 소비량에 따른 총 세포수와 산소 소비량 사 이에도 정의 관계가 있다고 보고 했다. 따라서, 본 연구는 수정란의 산소 소비량을 측정 하여 그 품질을 확인하고, 이를 바탕으로 체내수정란의 산소 소비량이 수태율에 미치는 영향을 구명하고자 수행하였다. 한우 체내수정란의 생산은 난소 및 자궁질환이 없는 건 강한 한우 공란우를 과배란을 유기하여 3 way Foley catheter를 이용하여 수정란을 채란 하였다. 체외수정란은 국립축산과학원 가축유전자원시험장 관행방법을 기준으로 생산하 여 시험에 사용하였다. 수정란의 산소 소비량 측정은 수정란 호흡장치(FHK, HV-405, Japan)를 이용하였고, 수정란 호흡 장치는 주사형 전기화학현미경(Scanning Electrochemical Microscopy, SECM)을 이용하여 산소 농도 분포를 각각 측정하였다. 한우 체내수정 란의 산소 소비량(10¹⁵/mol s— 1)을 측정하고 이를 수란우에 이식한 후 수태율을 조사한 결 과 산소 소비량이 가장 높은 12.0 이상에서 85.7%의 높은 수태율을 나타내었다. 이에 반 하여, 10.0 미만의 낮은 산소 소비량에서는 흥미롭게도 수태율이 0.00%를 나타내었다. 이런 결과들은 형태학적 등급이 좋을수록 수정란의 산소 소비량도 높아진다는 보고를 근 거하여, 산소 소비량이 높은 수정란을 이식하면 수정란이식 수태율이 높아진다는 것을 확인하였다.

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 work was to determine the effect of corpus luteum (CL) grade on pregnancy rate after embryo transfer in Korean cattle and we found that CL development was linked to pregnancy rate. The in vivo derived blastocyst-stage embryos were transferred to 15 recipients synchronized in the estrus cycles. Based on size and palpable characteristics, CLs were categorized into three grade. The grade three CL is not to be identified by rectal palpation. The pregnancy rates tended to increase with the increase in CL size of recipients. In grade one, two, and three, the pregnancy rates were 62.5%, 50.0%, and 0%, respectively. This result suggests that pregnancy rates after embryo transfer might be affected by the CL status of recipients.

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.