Bulman D C
Vet Rec. 1979 Nov 3;105(18):420-2. doi: 10.1136/vr.105.18.420.
Milk progesterone profiles were used to study the high incidence of embryonic mortality between 30 to 80 days after insemination in 91 cows in a single herd. The progesterone levels dropped to basal values at 46.7 +/- 1.37 days after service in 22 per cent of apparently pregnant cows. Embryo loss occurred significantly more frequently following services by one bull (Z). The mortality rates were 14/32 (44 per cent) in cows conceiving to Z compared with 8/73 (11 per cent) in cows conceiving to other bulls. There was no significant effect of the age of the cow or yield on the incidence of embryonic mortality.
利用牛奶中孕酮水平曲线，对单个牛群中91头奶牛授精后30至80天胚胎死亡率高的情况进行了研究。在22%看似怀孕的奶牛中，配种后46.7±1.37天孕酮水平降至基础值。由某一头公牛（Z）配种后胚胎丢失的情况明显更为频繁。与Z公牛配种受孕的奶牛胚胎死亡率为14/32（44%），而与其他公牛配种受孕的奶牛胚胎死亡率为8/73（11%）。奶牛年龄或产奶量对胚胎死亡率并无显著影响。
