In Vitro Methodology, Hormonal and Nutritional Effects, and Fiber Production in Isolated Ovine and Caprine Anagen Hair Follicles

The document reviews studies on the regulation of hair growth and protein synthesis in isolated anagen hair follicles from Angora and cashmere-bearing goats, utilizing in vitro techniques. It was found that mohair follicles from Angora goats had a faster rate of hair shaft elongation, higher DNA content, and deposited more protein compared to cashmere follicles. Both melatonin and prolactin positively influenced hair shaft growth and protein synthesis in these follicles, indicating direct effects on the follicles beyond systemic animal responses. Epidermal growth factor affected mohair follicle elongation and protein synthesis, and at higher concentrations, led to the formation of club hair structures. Biotin supplementation was essential for maintaining the viability of isolated sheep hair follicles, influencing growth and protein synthesis. Lastly, the presence of the amino acid l-methionine was necessary for the viability and growth of mohair follicles, with l-cysteine being beneficial but not essential when l-methionine was present. The studies suggest that understanding nutrient transport mechanisms and utilization is crucial for optimizing nutritional supply to hair follicles, which could be targeted in animal nutrition practices.