Vitamin A-responsive dermatosis in the dog.

In 3 dogs, focal, well-circumscribed skin lesions compatible clinically with seborrheic dermatitis responded to oral treatment with vitamin A. Skin biopsy findings were compatible with phrynoderma in man, a disease thought to be associated with vitamin A deficiency. The dogs had been fed commercial dog food and were otherwise healthy. The skin lesions resolved rapidly and completely with vitamin A therapy. Seven other dogs with similar lesions but with histopathologic findings not compatible with phrynoderma or follicular keratosis did not respond to vitamin A therapy.