Recognition of the Ultrastructure of the Hair Follicle of Cashmere Goats Under the Transmission Electron Microscope

This study analyzed the ultrastructure of hair follicles in Hexi cashmere goats using transmission electron microscopy over a year. It found distinct changes in the histomorphology of hair follicles throughout the year. In early development, transparent hair cells were present in the medulla, with programmed cell death occurring after hair stem formation. The inner root sheath showed a concentric arrangement of Huxley, Henle's layer, and cuticle during the development phase, but was not integral in early and late stages. Henle's layer keratinized earlier than other layers. The outer root sheath had multi-layered, square-arranged cells in the upper and middle positions, with a single flat layer at the bottom. The connective tissue sheath contained collagen fibers, elastic fibers, sensory nerve endings, and blood vessels, with no special changes observed during the hair follicle cycle. The study concluded that recognizing the ultrastructures of cashmere goat hair follicles could help accurately identify and localize follicle layers based on their morphological characteristics.