Hair loss (alopecia) is a common skin problem in dogs. Alopecia is extremely noticeable, with varied or symmetrical thin or bare patches accompanied by itching, scaling, crusting and inflammation around the area. This is probably mange, a skin disease caused by several species of tiny mites. Note: there are other reasons for hair loss but mites are a common cause.
Demodectic mange (also known as red mange or puppy mange) generally affects young dogs. The mite demodex canis is the culprit. It may surprise you to know that demodectic mites of various species live on the bodies of virtually every adult dog and most human beings, without causing any harm or irritation. These tiny mites that look like microscopic alligators live inside of the hair follicles.
The development of demodectic mange in dogs is because of their suppressed immune system. Whether or not demodex causes harm depends on the dog's ability to keep the mite under control. This is not a disease of poor conditions or dirty environment. It is usually a disease of young dogs that have inadequate or poorly developed immune systems. Older dogs that are suffering from a suppressed immune system are also susceptible. Demodex is not communicable to other dogs as long as they are healthy.
The mites transfer directly from the mother to the puppies within the first week of life by direct contact only. Lesions of demodectic mange, if present, usually appear first around the puppy's head, as this is the area most in contact with the mother. Virtually every mother carries and transfers mites to her puppies. Most puppies are immune to the mite's effects and display no clinical signs or lesions. A few are not immune and develop full-blown cases of mange.
Demodex mange usually appears after four months of age. There may be isolated lesions or generalized mange involving the entire body. The hair loss usually begins around the muzzle, eyes and head area. In cases in which the whole body is involved, there will be areas of hair loss over the entire coat. The skin will be crusty and inflamed. A secondary bacterial infection is common. Some animals can become quite ill and develop a fever, lose their appetite, and become lethargic. Dogs with generalized demodectic mange need immediate vigorous treatment.
The other most common mange mite is the sarcoptes scabiei, known as sarcoptic mange or scabies. Sarcoptic mites can infect healthy dogs of any age, breed or sex. They cause symptoms of hair loss and severe itching similar to demodex mites. The female mite burrows into the hosts' skin and begins to lay eggs as she tunnels into the skin. It may be that the itching caused by an infestation of the sarcoptic mite is actually an allergic reaction to the mite burrowing into the skin. Sarcoptic mange is transmittable to other dogs. The mites can live for several days off the host in the environment. Because of this, other dogs can get it without having contact with the infected dog.
Page 2 of 2 - If your pet has any of the symptoms of mange, take them to your veterinarian for diagnosis and treatment. Skin scrapings can help identify the species of the mite. Several scrapings or a biopsy will be done to confirm the presence and identify the mite. Your vet will prescribe medication to kill the mite. Depending on the type of mange, medication is applied topically, by injection, or by shampoo and dip. Your pet may also need antibacterial shampoo or anti-inflammatories and antibiotics to treat skin issues and ease inflammation. Although mites are quickly killed, results are not immediately seen and re-checks need to be done.
Final note; in the past before newer treatment methods were available, some people dipped their afflicted dogs in motor oil. This is not effective and can be extremely harmful to the dog.