A healthy dog will have clear skin and a healthy coat of fur. If your dog is experiencing dandruff that comes away in black flakes and has greasy skin, it could have a fungus skin infection.
Fungus Skin Infection
Canine skin infections caused by fungus are often triggered by a kind of yeast called malasezzia, according to "Skin Diseases of the Dog and Cat: Clinical and Histopathologic Diagnosis."
Yeast skin infections are most common in basset hounds, bulldogs and dachshunds, although they can occur in any breed.
Canine fungus skin infections often develop in a dog's ears or in folds of its skin. The skin will be greasy and smell musty. The dog will have dandruff and scabs that can be black in color.
Fungus skin infection can be treated with anti-fungal creams and shampoos, according to "The Complete Healthy Dog Handbook." Oral medications are available for severe or persistent fungus skin infections.
You can help prevent canine skin infections by bathing your dog with a mild shampoo. If your dog's greasy skin does not clear up after a bath, it is time to contact your veterinarian.