Joo Young Hoo, Jeong Seung Min, Paradhipta Dimas Hand Vidya, Lee Hyuk Jun, Lee Seong Shin, Choi Jeong Seok, Noh Hyeon Tak, Chang Hong Hee, Kim Eun Joong, Kim Sam Churl
Institute of Agriculture and Life Science, Gyeongsang National University, Jinju 52828, Korea.
Division of Applied Life Science (BK21Four), Gyeongsang National University, Jinju 52828, Korea.
J Anim Sci Technol. 2021 Nov;63(6):1265-1274. doi: 10.5187/jast.2021.e122. Epub 2021 Nov 30.
Two field experiments were conducted to improve the conception rate of Hanwoo cow. The first experiment aimed to investigate the physiological condition of Hanwoo cows on estrus, including metabolic profiles and body condition score (BCS). The second experiment investigated the effect of a novel estrus detector on the artificial insemination (AI) conception rate for Hanwoo cows. For the first experiment, 80 Hanwoo cows (2.5 ± 0.10 of parity), approximately one month before estrus, were housed in 16 pens and offered the experimental diets twice daily with free water access. The BCS were recorded, and blood was collected from the jugular veins just before AI. The collected blood was used to measure physiological conditions, such as metabolite and hormone levels. For the second experiment, each cow was equipped with a neck-mounted estrus detector collar, which had a sensor connected through the internet. Approximately one month before estrus, three hundred sixty Hanwoo cows (2.4 ± 0.21 of parity) were assigned into groups with or without W-Tag collar treatments. The animals were managed the same as in the first experiment. The pregnancy rate reached 55% in the first experiment. The concentration of luteinizing hormone (LH) was higher ( < 0.012; 1.56 vs. 1.08 ng/mL) in cows that were not pregnant (NPG) than in cows that were pregnant (PG) after AI. The BCS and other concentrations of metabolites and hormones in the blood were not different in both NPG and PG cows. The ranges of estrogen, LH, and follicle-stimulating hormone for PG cows were 11.9 to 39.0 pg/mL, < 0.25 to 1.98 ng/mL, and < 0.50 to 0.82 ng/mL, respectively. In the second experiment, cows with the estrus detector had lower days open ( < 0.001; 78.1 vs. 84.8 d), insemination frequency ( < 0.001; 1.26 vs. 2.52), and return of estrus ( < 0.001; 70.9 vs. 79.1 d) than those in cows without the estrus detector. In conclusion, the present study indicated that lower LH concentration just before AI potentially increased the pregnancy rate of Hanwoo cows. Furthermore, the application of estrus detectors to Hanwoo cows could improve the conception success rate for AI.
进行了两项田间试验以提高韩牛的受孕率。第一个试验旨在调查韩牛发情时的生理状况，包括代谢特征和体况评分（BCS）。第二个试验研究了一种新型发情检测器对韩牛人工授精（AI）受孕率的影响。在第一个试验中，80头韩牛（胎次2.5±0.10），在发情前约一个月，被安置在16个栏中，每天提供两次试验日粮并自由饮水。记录体况评分，并在人工授精前从颈静脉采集血液。采集的血液用于测量生理状况，如代谢物和激素水平。在第二个试验中，每头牛都佩戴一个颈部安装的发情检测器项圈，该项圈有一个通过互联网连接的传感器。在发情前约一个月，360头韩牛（胎次2.4±0.21）被分为接受或不接受W-Tag项圈处理的组。动物的管理与第一个试验相同。在第一个试验中，受孕率达到55%。人工授精后，未怀孕（NPG）母牛的促黄体生成素（LH）浓度高于怀孕（PG）母牛（P<0.012；1.56对1.08 ng/mL）。NPG和PG母牛的体况评分以及血液中其他代谢物和激素的浓度没有差异。PG母牛的雌激素、LH和促卵泡激素范围分别为11.9至39.0 pg/mL、<0.25至1.98 ng/mL和<0.50至0.82 ng/mL。在第二个试验中，佩戴发情检测器的母牛的空怀天数（P<0.001；78.1对84.8天）、输精次数（P<0.001；1.26对2.52）和发情回归天数（P<0.001；70.9对79.1天）均低于未佩戴发情检测器的母牛。总之，本研究表明人工授精前较低的LH浓度可能会提高韩牛的受孕率。此外，将发情检测器应用于韩牛可以提高人工授精的受孕成功率。
