Seasonal Moulting in Adult Male Raccoon Dog (Nyctereutes Procyonoides)

The study investigated seasonal moulting in adult male raccoon dogs through quantitative histology and external observations. It was found that these animals experience a significant shedding of old winter underfur in the spring, followed by a period of intensive growth of new winter hair in the autumn. During the summer, only a few mature and growing underfur hairs were present. The development of new intermediate and large guard hairs began in April and May, with all new guard hairs fully developed by the end of June. The growth periods for new winter guard hairs and underfur hairs were approximately 7 months and 3.5 months, respectively. By the end of November, the winter fur had matured, with bundles containing an intermediate guard hair having more underfur hairs than those with a large guard hair. Additionally, the thickness of the dermis and the intensity of skin color reached their peak during the autumn moult, suggesting a strong connection to the activity of hair follicles.