Demodicosis in black bears (Ursus americanus) from Florida.

Demodicosis was diagnosed in five black bears (Ursus americanus) from north-central Florida. The first bear examined, a 5-yr-old male, had severe alopecia except for the dorsal neck, paws, and ears. The skin was characterized by moderate orthokeratotic hyperkeratosis, and mild to moderate follicular hyperkeratosis. Superficial dermatitis, follicular pustules, and epidermal pustules were present, but rare. Specimens of Demodex sp. were seen most commonly within hair follicles devoid of hair and at the infundibulum of sebaceous glands. Four additional bears from the same area also had some degree of alopecia and skin scrapings were positive for Demodex sp. This mite may be common, although its prevalence is not known.