Effects of short photoperiod on cashmere growth, hormone concentrations and hair follicle development-related gene expression in cashmere goats

Shanbei White Cashmere goat is a typical goat species, the growth of cashmere is affected by photoperiod. To further investigate the effects of short photoperiod treatment on cashmere growth, hormone concentrations and hair follicle development-related gene expression in cashmere goats, twenty Shannbei white cashmere goats were selected and randomly divided into long-day photoperiod treatment group and short-day photoperiod treatment group. The results revealed the cashmere on short-day photoperiod treatment began to develop earlier, and its length and growth rate increased dramatically (P < 0.05). The short-day photoperiod treatment increased the concentration of serum Melatonin, reduced the concentration of serum prolactin, decreased the expression of estrogen receptor alpha and raised the expression of hair follicle development-related genes [catenin beta-1, Bone morphogenetic protein 2, Fibroblast growth factor 5 and platelet-derived growth factor subunit A] (P < 0.05), thereby accelerating the reconstruction of the secondary follicle, increasing the density of the secondary follicle (P < 0.05) and triggering the growth of cashmere goats. The present study provides new insights into the dynamic changes in cashmere growth, hormone concentrations and hair follicle development-related gene expression in cashmere goats under short photoperiod, and is expected to be useful for future studies on intensive feeding research.