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.

The objective of this study was to assess the effect on post-thawed sperm motility, viability and acrosome integrity of boar semen frozen in the freezing extender with chicken or duck egg yolks. The Sperm rich fraction of ejaculates from three Duroc boars were collected by a glove-hand technique. Samples with more than 80% motile sperm were used for this experiment. Semen was diluted with freezing extender (LEY) containing 11% (v/v) lactose, 20% (v/v) hen egg yolk with 3.5% (v/v) glycerol, and 0.5% (v/v) Orvus Es Paste(OEP, Nova Chemical Sales Inc., Scituate, MA. USA) to yield a final sperm concentration of 5×108 cells/ml. Following complete dilution, semen samples were loaded in 0.5 ml French medium straws (IMV technologies, France) and transferred to programmable semen freezer (SY-LAB Gerate GmbH, Austria). For freezing the semen samples, each straw was cooled from 5℃ to — 5℃ at 6℃/min, auto-seeding at — 5℃ and held for 60sec, samples were then cooled from — 5 to — 80℃ at 40℃/min, and thereafter from — 80℃ to — 150℃ at 60℃/min. The yolks used were sourced from fresh chicken and duck eggs. To evaluate the post-thaw sperm quality, semen was thawed at 38℃ for 20 sec and sperm motility, viability and acrosome integrity were assessed. Motility was assessed for %motile cell characteristics using computer-assisted semen analysis (CASA; SAIS SI-100, Medical supply, Korea). The percentage of sperm viability was assessed using LIVE/DEAD® sperm viability kit (Molecular probes, Eugene, OR, USA). The acrosome integrity was assessed by FITC-PNA staining. Sperm quality in terms of motility, viability and acrosome integrity showed higher after freezing in medium containing duck yolk than chicken yolk. However, there was no significant difference in sperm quality for the different types of yolk(p>0.05). * The result of this study showed that there was no significant difference between the egg yolk types when considering the sperm motility, viability and acrosome integrity of boar semen frozen in the freezing extender with chicken or duck egg yolks.

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.