Reynaert R, De Groot W, Marcus S, Peeters G
Ann Endocrinol (Paris). 1976 Mar-Apr;37(2):75-82.
A large number of blood samples was taken from the jugular vein of 18 cows or heifers during parturition, especially during stage II. In 9 animals an increase in serum growth hormone was observed and the peak occurred within the period which began when the forelegs of the calf became visible in the vulva, and ended a few minutes after expulsion of the calf. In typical cases, the growth hormone peak was preceded by a progressive increase, and followed by a gradual decrease in the hormone level. The total duration of the phenomenon amounted to a few hours. During the days before and after parturition, no change in growth hormone concentration could be noted. The serum free fatty acid values were high during parturition.
在分娩期间，特别是分娩第二期，从18头母牛或小母牛的颈静脉采集了大量血液样本。在9头动物中观察到血清生长激素增加，峰值出现在从外阴部可见小牛前腿开始到小牛排出后几分钟结束的时间段内。在典型病例中，生长激素峰值之前是逐渐增加，之后激素水平逐渐下降。这种现象的总持续时间为几个小时。在分娩前后的几天里，生长激素浓度没有变化。分娩期间血清游离脂肪酸值较高。
