The objective of this study was to estimate the growth curve parameters of body weight for female Elk. Weight and age data from 115 does raised at the Animal Genetic Resources Research Center in Korea were used in this study. The growth curve parameters were estimated from a nonlinear regression using Gompertz and Logistic models. Mature weight (A), growth ratio (b) and maturing rate (k) of female Elk were 214.1±2.17 kg, 2.12±0.0045 and 0.0043±0.00011, respectively, according to the Gompertz model. They were 208.3±2.17 kg, 5.56±0.234 and 0.0065±0.00017, respectively, according to the Logistic model. The goodness of fit determined by R2 was higher in the Gompertz model than that in the Logistic model. The growth curve functions obtained from the Gompertz and Logistic models in female Elk were f(t)=214.1×e-2.124×e-0.00484×t and f(t)=208.3×(1+5.561×e-0.00651×t)-1, respectively. The absolute growth rate functions from the Gompertz and Logistic models in female Elk were f'(t)=0.0043×f(t)×1n(214.1/f(t)) and f'(t)=0.0065×f(t)×[1-f(t)/208.3]respectively. The growth pattern of female Elk generated from this study can be useful in determining the most appropriate feeding plans and the best breeding strategies for deer.

This study was conducted to investigate the effect of pasture grazing and barn feeding system on the growth performance, weight gain and velvet antler productivity in Elk. Twelve 5-year-old elk stags about 273 kg were stratified by weight and randomly assigned by feeding system (a pasture grazing and a barn feeding, n=6). The average feed intake were not signigicant difference between two groups. Average daily gain for grazing and barn feeding group was 0.25 g and 0.29 g respectively, showing no significant difference. Velvet antler yield for grazing and barn feeding group was 7,700 g and 6, 960 g respectively, with no significant difference. In conclusion grazing group was better than barn feeding group in feed intake, body weight gain and velvet antler productivity. However, there were no statistical significant difference between the two group. These results may serve as the basis for further study of deer feeding system in Korea and further study needed to examine the grazing intensity and economic efficiency.

This study was conducted to estimate growth curve parameters by sex in Korean native Goat. Weight-age data from 148 male goats and 169 female goats raised at Animal Genetic Resources Research Center in Korea were used in this study. Growth curve parameters were estimated from nonlinear regression using Gompertz and Logistic models. Mature weight ( ) and growth rate () of male goats were 50.0 kg, and 0.0038, respectively, when Gompertz model was used. They were 47.9 kg and 0.0062, respectively, when Logistic model was used. In female goats, mature weight ( ) and growth rate () were 35.8 kg and 0.0030, respectively, when Gompertz model was used. They were 34.6 kg and 0.0046 when Logistic model was used. The goodness of fit determined by R2 was higher in the Gompertz model than that in the Logistic model. The growth curve functions estimated from the Gompertz model in Korean-native male and female goats were , respectively. The inflection point () showed that the maximum growth rate and the weight at inflection (  ) estimated from the Gompertz model were 234.8 days and 18.37 kg, respectively, in male goats. They were 235.7 days and 13.16 kg, respectively, in female goats. The growth pattern of Korean-native goats obtained from this study might be useful for determining their feeding and management plans by sex and design breeding strategies.

The objective of this study was to identify the phenotypic relationships among calving difficulty, calf birth weight and gestation length of Holstein dairy cattle under the environment of Korea. A total of 1,834 calving records collected by Dairy Science Division of National Institute of Animal Science, RDA from 2000 to 2014 was analyzed. General linear multivariate models for calving difficulty scores (CD: 1=no assistance, 2=minor assistance, 3=two to three persons assisted, 4=more than three persons assisted, 5=cesarean section), calf body weight at birth (BW), and gestation length (GL) included fixed effects of year and season (spring, summer, autumn, winter) of births (YS), sex of calves, and parity. For GL and BW, all three fixed effects (YS, sex of calves, parity) were significant (p<0.05). For CD, the effects of YS and sex of calves were significant (p<0.05). Bull calves were born with heavier BW by 3.18 kg, with greater CD by 0.18 point and with longer GL by 0.6 days than heifer calves. The least squares mean of BW was the heaviest at the third parity (44.1 kg) compared to those at the first, the second and the fourth parities or later (41.3-41.9 kg). The least squares mean CD at the first parity was 1.74 point, which was higher than CD at the second and later parities (about 1.68 points). Phenotypic correlation (partial residual correlation) between GL and BW was 0.36. But those between GL and CD and between BW and CD were -0.03 and 0.04, almost zeros. To conclude, we observed higher incidence of calving difficulty in the first calving than in the later ones. Further investigation on the relationships between calf’s birth weight and calving difficulty is needed

돼지의 육질과 관련하여 지방침착의 중요도가 높아짐에 따라 지방대사 또는 지방축적과 관련한 후보유전자 발굴 을 위해 등지방 조직 유래의 cDNA microarray를 이용하여 품종별 지방함량관련 조직의 유전자 발현 양상을 분석하 였다. 그 결과 재래돼지의 등지방 조직에서 SCD (stearoyl-CoA desaturase)와 ELOVL6 (elongation of very long chain fatty acid 6)가 높은 발현을 보였고, 간에서 FMO1 (hepatic flavin-containing mono oxygenase)이 높은 발현을 보였으며, 요크셔는 간에서 FGG (fibrinogen gamma polypeptide)와 C3d (com- plement component c3d), 등지방에서 COL3A1 (type Ⅲ collagen alpha 1)이 높은 발현을 보이는 것을 확인하였다. Real-time PCR을 통해 microarray data의 validation과 품종간 유전자 발현량을 비교하여, 위의 유전자들 중 지방함량에 따른 차등발현 유전자로 SCD, ELOVL6 그리고 FGG를 선정하였다. 선정된 유전자 SCD, ELOVL6, FGG는 지방대사에 관여하며 근내지방 함량에도 영향을 미쳐 향후 육질개선에 유용한 후보유전자로 서 활용가능성을 제시하였다.

This study was performed to identify the differentially methylated region (DMR) and to examine the mRNA expression of the imprinted H19 gene in day 35 of SCNT pig fetuses. The fetus and placenta at day 35 of gestation fetuses after natural mating (Control) or of cloned pig by somatic cell nuclear transfer (SCNT) were isolated from a uterus. To investigate the mRNA expression and methylation patterns of H19 gene, tissues from fetal liver and placenta including endometrial and extraembryonic tissues were collected. The mRNA expression was evaluated by real-time PCR and methylation pattern was analyzed by bisulfite sequencing method. Bisulfite analyses demonstrated that the differentially methylated region (DMR) was located between -1694 bp to -1338 bp upstream from translation start site of the H19 gene. H19 DMR (-1694 bp to -1338 bp) exhibits a normal mono allelic methylation pattern, and heavily methylated in sperm, but not in oocyte. In contrast to these finding, the analysis of the endometrium and/or extraembryonic tissues from SCNT embryos revealed a complex methylation pattern. The DNA methylation status of DMR Region In porcine H19 gene upstream was hypo methylated in SCNT tissues but hypermethylated in control tissues. Furthermore, the mRNA expression of H19 gene in liver, endometrium, and extraembryonic tissues was significantly higher in SCNT than those of control (p<0.05). These results suggest that the aberrant mRNA expression and the abnormal methylation pattern of imprinted H19 gene might be closely related to the inadequate fetal development of a cloned fetus, contributing to the low efficiency of genomic reprogramming.

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.

We investigated the cleavage rate and blastocyst yield for each culture condition to enhance tolerance of cryo-preservation of bovine IVF embryo with relatively lower cryo-tolerance compared to in vivo embryo. The cleavage rate and blastocysts yield for CR1aa, IVMD, IVD, CR1aa+10% FBS were 73.2, 69.3, 72.8, 68.5% and 44.1, 30.8, 33.3, 48.0%, respectively. The values did not differ among each treatments without serum. For embryo vitrification, In vivo and In vitro blastocysts were exposed to VS1(10% glycerin, 0.1 M glucose, 0.1 M sucrose, PEG 1%) for 5 min, and VS2 (10% glycerin, 10% EG, 0.2 M glucose, 0.2 M sucrose, PEG 2%) for 5 min and then VS3 (10% glycerin, 30% EG, 0.3 M glucose, 0.3 M sucrose, PEG 3%) for 1 min. The exposed embryos were then loaded into the 0.25 ml plastic straws and then plunged into liquid nitrogen. The straws were held for period of 1 to 2 weeks before thawing. In embryo viability, no differences in blastocyst re-expansion rates were found between in vivo and in vitro embryos. whereas expansion-BL rates was significantly higher for in vivo-derived embryos (72.7%) when compared to in vitro-derived embryos (51.4%), respectively (P<0.05). In conclusion, our results indicate that combined use of CRIaa culture medium with vitrification might enhance tolerance of cryopreservation for bovine IVF embryo production.

The objective of this study was to investigate the effects of abnormal ovarian cycles after superovulation treatment of 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 was administered. Cows were artificially inseminated twice after estrous detection at 12 hr intervals. The cows received GnRH at the time of Ind insemination. Embryos were recovered 7 or 8 days after the 1st insemination. The cows were considered to have resumed ovarian cyclicity on the day of ovulation if followed by regular ovarian cycles. 50.0 percentage of the cows (18/36) had normal resumption of ovarian cyclicity (resumption within 40 days after superovulation), and 50.0% (18/36) had delayed resumption(resumption did not occur until>40 days after superovulation). Delayed resumption Type II (first ovulation did not occur until 40 days after superovulation, i.e. delayed first ovulation 33.3%) were the most common types of delayed resumptions. The mean numbers of total ova from < 10 and 10 of corpora lutea (CL) was 7.3 and 13.9, respectively. The number of transferable embryos differed between < 10 and 10 CL was 4.2 and 5.1, respectively. 11.1 percentage of the cows (4/36) did not resumption their ovarian cyclicity until 60 days after superovulation treatment.

Oxygen consumption has been regarded as a useful indicator for assessment of mammalian embryo quality. This study was performed to investigate whether oxygen consumption reflects morphological grade of in vivo derived bovine blastocyst-stage embryos (blastocyst). The oxygen consumption of in vitro produced blastocyst was compared to its total cell number. In addition, pregnant rate was measured after transplantation of in vivo blastocysts with different oxygen consumption. The quality of blastocyst collected on day 7 after artificial insemination was categorized as grade I and II (G I and G II) based on microscopic observation of the morphology. Oxygen consumption of blastocyst was measured using a scanning electrochemical microscopy (SECM) and total cell number of in vitro blastocyst was enumerated by counting cells stained by propidium iodide. Pregnancy of recipient cow was confirmed with rectal palpation after 60 days of embryo transfer. The oxygen consumptions of G I blastocysts were significantly higher than those of G II blastocysts ( versus , 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 respectively. Total cell number was significantly increased in embryos with high oxygen consumption (p<0.05). Pregnant rate in recipient cow was 0, 50, and 85.7% in the transplantation of embryo with the oxygen consumption of below 10.0, 10.0~12.0, and over , respectively. These results suggest that measurement of oxygen consumption may help increase the pregnant rate of bovine embryos.

In vivo embryo produced from Hanwoo donor cows were collected and transferred to Hanwoo recipients. Cows, at random stages of the estrous cycle, received Progesterone Releasing Intravaginal Device (CIDR-plus, InterAg, New Zealand) together with injection of 1 mg estradiol benzoate and 50 mg progesterone, and gonadotropin treatment began 4 day later. For superovulation, a total of 28 mg FSH was intramuscularly injected twice a day in the way of decreasing doses 4 day (5, 5, 4, 4, 3, 3, 2 and 2 mg). Twenty one Hanwoo donor cows were flushed on day 7 of estrus cycle with same FSH and artificial insemination by the same technicians. Embryos were recovered 7 days after the second insemination by flushing the uterus with Embryo Collection Medium. The results obtained were as follows: The rates of transferable embryos were 50.3%, and 78 fresh embryos at morulae and blastocysts stage were transferred into Hanwoo recipients on day 7 of estrus cycle. The pregnancy rates were first embryo transfer 55.6%, 2nd 62.9% and 3rd 57.9%, respectively. In conclusion, These results suggest that CIDR-based superovulation protocol may be effectively used for production of superior Hanwoo embryos. Also, since it seems the condition of recipient cows greatly affect pregnancy rate, it is very important to evaluate recipient for effective cattle production.

It is not easy for porcine embryos produced by in vitro systems to develop into blastocysts with high quality. To solve this problem, many researchers have developed novel culture methods. However, the formation of blastocysts with high quality is still low. In this study, we aimed to produce piglet following transfer of in vitro produced early embryos ( cell stage embryos) or morula and blastocyst. The cell stage embryos were transferred to five estrus-synchronized recipients (200 embryos per recipient). One of the five sows farrowed three piglets, which contain two live piglets and one dead piglet, 114 days after embryo transfer. However, two recipients transferred with morula and blastocysts did not farrow. Microsatellite analysis confirmed that the genomic DNA of two live piglets were not genetically identical to that of the recipient. These results indicate that it is possible to obtain piglets by transfer of early embryos produced by in vitro production (IVP) systems.