You may have seen a dog with patches of hair or sores on its skin, or had to deal with this in your own dog. Sometimes, this condition is the result of a parasitic infection called mange. There are three different types of mange, each the result of a different type of mite. These mites are demodex, sarcoptes scabiei, and cheyletiella. The mites either live on the skin surface or burrow into the skin. The result is usually a lot of irritation and itchiness. The dog may also get secondary bacterial infections, which leads to sores and bald spots. The outbreak can be in only specific places on your dog's body, such as the face and feet. When the outbreak is all over the body, it is described as "generalized." Two forms can be prevented (sarcoptic and cheyletiella) whereas demodex cannot. However, it can be controlled if you are aware of the symptoms and obtain and apply the correct treatment. Effective treatment requires prescription medication, which means your first stop for a dog with skin problems should be your veterinarian.