奶牛发情期的奶孕酮分析

<正> 影响奶牛人工授精成功率的主要原因是对发情期能否正确判断,适时输精。据1981年联邦德国Bavarian动物健康服务机构的报告,输精时间不正确,是影响奶牛繁殖率的重要因素。由于孕酮含量在发情周期中呈规律性变化,在发情期显著下降,因此可

RADIO-IMMUNOASSAY OF MILK PROGESTERONE DURING OESTRUS IN DAIRY COWS

During estrus, the progesterone levels in milk of 48 cows were < 2 ng/ ml in 36 cows (75%), 2.3-5.0 ng/ml in 8 cows (16.75%), >7 ng/ml in 4 cows (8.3%). 5 cows (10.4%) had pseudoestrus and their milk progesterone continuously maintained high levels. In cows with normal oe-strous cycles, oestrus appeared 1-2 days after the progesterone level had declined to basal value. The milk progesterone levels were at the basal value far about 6 days around oestrus and then increased gradually. On the day of insemination, the mean milk progesterone level was 1.86 + /-1.84 ng/ml (n= 8 ) in pregnant cows and 1.25+/-0.92 ng/ml (n = 11) in non-pregnant cows. The difference was not significant (P>0.05) .