Studies on Abnormal Moulting in the Farm‐Raised Blue Fox (Alopex lagopus)

Summary In a farm-raised, adult female blue fox (Alopex lagopus) it was observed that apparently the winter coat was shed abnormally. Furthermore, the individual was never recorded as being on heat. Comparative histological and clinical-chemical examinations showed that the winter coat cycle was postponed approximately 6 months, and that the hair growth therefore took place in the spring. At first a kind of biological summer coat was produced, and then a biological mature winter coat. This was compared with and partly documented by changes in plasma estradiol and cortisol profiles. It could be concluded that the hair growth cycle and the plasma estradiol profile showed an abnormal seasonal variation in the abnormal fox. The two variables seemed, however, to be correlated as in a normal animal.