Fabry J, Bulteau M, Thielemans M F, Oger R, Reuter A M, Franchimont P
Ann Endocrinol (Paris). 1984;45(2):119-24.
Seasonal variation of prolactin nyctohemeral rhythm has been studied by radioimmunoassay on female cattle of the white blue belgian breed. Animals are divided into three groups as age is concerned : 6 calves, 6 heifers and 5 lactating cows. In december all groups of animals show a significant increase of plasma prolactin concentration between 5 a.m. and 7 a.m. Calves and heifers have a second secretion period either at the end of the afternoon between 17 and 19 p.m. or during the evening between 20 and 23 p.m. The circadian rhythm observed in may with heifers is similar to that in december with two waves whose relative importance is different at the two seasons considered. Nyctohemeral rhythm of prolactin in cattle is age and season dependent.
通过放射免疫分析法研究了比利时白蓝牛雌性动物催乳素昼夜节律的季节性变化。根据年龄将动物分为三组：6头犊牛、6头小母牛和5头泌乳母牛。12月，所有动物组在凌晨5点至7点之间血浆催乳素浓度显著升高。犊牛和小母牛在下午晚些时候17点至19点或晚上20点至23点有第二个分泌期。5月小母牛观察到的昼夜节律与12月相似，有两个波，在两个季节其相对重要性不同。牛催乳素的昼夜节律取决于年龄和季节。
