Fleas are the most common parasitic skin disease found in dogs. Mange is another type of skin disease which is caused by mites. Ear mites, lice, and ticks are other parasites that affect dogs. Their presence irritates the dog, leading to self-mutilation. A dog's ears, front legs, chest and abdomen are most often affected by sarcoptic mange.
Demodectic mange can cause itching.
The face and front legs are most commonly affected, although some cases may be generalized. Generalized demodectic mange is often a sign of underlying internal disease or a hereditary problem. Ear mites cause severe irritation in the ears. Often, an affected dog will scratch the hair off the back of its ears. Ticks, lice and fleas may transmit other diseases, in addition to causing irritation.