Effects of Photoperiod Change on Serum Hormone Levels, Hair Follicle Growth, and Antioxidant Status in Skin Tissue of Cashmere Goats

This study on 18 female Arbas cashmere goats over 60 days examined the effects of photoperiod changes on hormone levels, hair follicle growth, and antioxidant status. It found that both short-day (SDPP) and shortening-day (SPP) photoperiods increased melatonin levels, which influenced other hormones like prolactin and thyroxine, enhancing hair follicle activity and morphology. The SDPP group showed increased antioxidant activity in skin tissue, while both SDPP and SPP groups exhibited upregulation of genes crucial for hair follicle development and antioxidant defense. These changes improved cashmere growth by promoting secondary hair follicle activity and increasing hair bulb width, suggesting that manipulating light exposure can significantly impact cashmere production.