Effects of lighting conditions on regulatory mechanism of growth hormone secretion in cattle.

为了阐明光照对牛生长激素分泌的影响，测定了不同光照条件下牛生长激素的分泌规律。目前的研究表明，该物种生长激素的分泌具有6h间隔的超常节律，光刺激可以改变这种分泌节律。在畜牧业中，适当控制光照条件可能通过分泌生长激素来提高牛的生产力。

To clarify the effects of light on growth hormone secretion in cattle, GH secretory patterns under various lighting conditions were determined. The present study showed that GH secretion has an ultradian rhythm with 6-h interval in this species and that photic stimulation can alter the secretory rhythm. It is possible that appropriate control of lighting conditions improves productivity of cattle via GH secretion in animal industry.