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Demodectic Mange (demodicosis)

General Information

Demodicosis is a skin disease caused by a microscopic parasitic mite. Demodectic mites are found in small numbers in the hair follicles of normal dogs. In dogs with demodicosis, however, these mites proliferate, and large numbers inhabit the skin and hair follicles, probably because of some defect in the function of their immune system. This dysfunction may be temporary or it may be perminant. Anything that suppresses the function of the immune system (stress, immuno suppressive disease, immuno suppressive drugs, reproductive cycles, injury, etc.) makes it more difficult for the host to resist the mites. Dogs may acquire mites from their mother 2-3 days after birth.

Demodicosis may involve only 1 or 2 small areas of skin (localized mange) or large areas of the body (generalized mange). Juvenile-onset demodicosis occurs in dogs 3-12 months old, and the short-haired breeds are most commonly affected. Adult-onset demodicosis generally occurs in dogs more than 5 years old, and is often associated with disease or some other process that suppresses the immune system. Some dogs are genetically predisposed to the generalized form presumably due to a problem with the immune system, and breeding these dogs is not recommended.

Localized demodicosis is the mildest form. Usually only a few areas of hair loss on the head or front legs occur. Most dogs with the localized form recovery completely.

Generalized demodicosis is serious and often difficult to treat. Large areas of the body may be affected, and often the affected areas are also infected by bacteria. In these cases, the skin is red, crusty and warm, and has many pustules. It may bleed easily and has a strong, rancid odor. While most of these cases are curable, some can only be controlled, and periodic re-treatment is sometimes necessary.

Demodicosis also occurs as a chronic foot infection in mature dogs.

Important Points in Treatment

1. All medication and treatments must be given as directed and on schedule. Please call the doctor if you cannot complete any treatments or doubt the adequacy of your treatment.

2. Diet: Follow the instructions checked:

____Feed the normal diet.

____A special diet is necessary. Feed:

3. Activity: With localized demodicosis, your dog's activity need not be restricted. With generalized demodicosis, activity is restricted to avoid irritation and trauma to the inflamed skin. Restrict your dog's activity for ____ weeks.

4. Periodic rechecks and skin scrapings to test for active mites are necessary. With the generalized form, bacterial cultures from the skin may be needed to determine the most effective antibiotic.

Notify the Doctor if Any of the Following Occur:

* Your dog's sores enlarge rapidly and general skin health worsens.

* Your dog's appetite and activity are decreasing.

* Your dog's condition recurs after an apparent recovery.