关键词: 双抗EIA, 乳牛[49ME], 奶, 孕酮, 发情周期[49MC]

Abstract: Milk progesterone levels were measured daily using double antibodyEIA during oestrous cycle in 14 dairy cows. The results show that milk progesterone levels were low from day 1 to day 5(<3ng/mL) after A, I., Progesterone levels rose gradually from day 6 to day 10(>3-<8ng/mL); an abrupt rise was observed on day 11 and was maintained through day 19(>8ng/mL); and progesterone levels began to decrease on day 20 and declined sharply to low level(<1ng/mL)on day 21. Milk progesterone levels in pregnant cows were significant higher than those of non-pregnant cows(P<0.01) during 21-24 days after A. I., It is concluded that the double antibody EIA has practical value for measurement of milk progesterone level and can be used for early pregnancy diagnosis in dairy cows.

Key words: DOUBLE ANTIBODY EIA, DAIRY CATTLES, MILK, PROGESTERONE, ESTRUS CYCLE