Zinc is a trace mineral required for hair growth and maintenance of the skin. A deficiency of zinc causes thinning of the hair and a scaly, crusty dermatitis over the face, most noticeable on the nose and around the eyes, ears, and mouth. Crusts also appear over pressure points such as the elbows and hocks. The feet become callused and crack easily.
Siberian Huskies, Alaskan Huskies, Doberman Pinschers, Great Danes, and Alaskan Malamutes are predisposed to zinc-responsive dermatosis. A genetic defect involving zinc absorption from the intestines has been identified in Siberian Huskies, Alaskan Huskies, and Malamutes. In these breeds the disease may occur even when the dog is eating a well-balanced diet.
Diets high in fiber and calcium may precipitate zinc deficiency by binding zinc in the gastrointestinal tract. A zinc deficiency syndrome occurs in large- breed puppies fed diets that are oversupplemented with vitamins and minerals (particularly calcium). A closely related condition has been observed in dogs fed dry, generic dog foods that are deficient in zinc.
Treatment: The diagnosis is confirmed by the response to therapy. Regardless of the cause, the dermatosis responds rapidly to zinc sulfate (10 mg per kilo of body weight, daily) or zinc methionine (1.7 mg per kilo of body weight, daily). Improvement begins almost at once. Affected Alaskan Malmutes, Alaskan Huskies, and Siberian Huskies usually require zinc supplements for life.
Puppies with an acquired zinc deficiency respond to zinc supplements and a nutritionally balanced diet.