Seasonal Fiber Growth Cycles of Ferrets (Mustela Putorius Furo) and Long-Term Effects of Melatonin Treatment

The study investigated the seasonal hair growth cycles of ferrets and the long-term effects of melatonin treatment. Researchers monitored hair follicles in ferrets aged 3 to 19 months over three fur growth cycles. Melatonin implants elevated circulating melatonin for about 50 days, causing treated ferrets to grow their first winter and subsequent summer coats 18 days earlier than untreated controls, though this effect did not persist into the second winter. Reimplantation the following year again advanced autumn follicle growth. Both sexes showed similar timing in natural autumn fiber growth and response to melatonin, but males experienced fiber regrowth 4-6 weeks later than females in spring. Melatonin also advanced spring oestrus by 3-4 weeks. The study concluded that altering photoperiodic and hormonal controls can impact ferret pelage and reproductive cycles for up to 10 months.