影响奶牛产后卵巢活动恢复的几个因素

Several factors affecting restoration of ovarian activity during post partum dairy cows.

应用通讯奶样放射免疫分析法测定奶中孕酮含量，确定了１６４头次奶牛产后卵巢活动恢复的时间，并根据年产奶量、产犊季节和有无子宫内膜炎等进行分类统计．产后卵巢活动恢复延迟高产（１００００～７０００ｋｇ）奶牛中有５２．４％（１１／２１）；低产奶牛中占４１．３％（２６／６３）．秋季产犊的奶牛较早恢复卵巢活动，其次是冬季、春季和夏季．患子宫内膜炎的奶牛，有６６．７％产后卵巢活动恢复延迟，配种无效占５０．０％，情期受胎率为１４．３％．

Radioimmunoassay of progesterone in milk samples was performed to detemnine the time of restoration of ovarian activity during postpartum in dairy cows. The cows were classified according to milk yield, calving season and endometritis. 52.4% of dairy cows with high milk yield (10 000～7 000 kg per year) delayed the restoration of ovarian activity. However, only 41.3% of the cows with low milk yield had the delayed restoration of ovarian activity. The cows calving in autumn had earliest restoration compared with the cows calving in other seasans and the lowest restoration was detected in the cows calving in summer. 66.7% of the cows with endometritis had low conception rate after first insemination (14.3%) delayed their restoration of ovarian activity, with 50% of conception failure.