Studies on the improvement of reproductive efficiency in Korean native cows -Plasma progesterone concentrations during the estrous cycle and early pregnancy- |
Byong-kyu Kang1, Han-sun Choi1, Chung-gill Lee1, Chang-ho Son1, Guk-hyun Suh2 |
1College of Veterinary Medicine, Chonnam National University 2Namwon Branch, National Animal Breeding Institute |
한우(韓牛)의 번식효율(繁殖效率) 증진(增進)에 관한 연구(硏究) -발정주기(發情周期) 및 임신초기(姙娠初期)의 progesterone 농도변화(濃度變化)- |
강병규1, 최한선1, 이정길1, 손창호1, 서국현2 |
1전남대학교 수의과대학 2국립종축원 남원지원 |
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Abstract |
A study was conducted to improve the reproductive performance of Korean native cows. Plasma progesterone concentrations were determined by radioimmunoassay during the estrous cycle and early pregnancy. Plasma progesterone concentrations during the estrous cycle in the 15 cows were the lowest (0.30ng/ml) at estrus, gradually increased after 6 days, remained high from 8 to 17 days (3.87~5.59ng/ml) and drastically decreased thereafter to reach minimal concentrations at the next estrus. Plasma progesterone concentrations of the 10 pregnant cows at 20 days after insemination were $5.82{pm}1.33ng/ml$ (mean${pm}$SD) and those of 10 non-pregnant cows were $0.30{pm}0.21ng/ml$, respectively. Therefore, plasma progesterone concentrations in the pregnant cows at 20 days after insemination were significantly higher than in non-pregnant cows (p<0.001). |
Key Words:
Progesterone, estrous cycle, Korean native cow |
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