Demodicosis in Dog

Ectoparasitic infestation is the single most important cause of dog skin disease. Demodicosis is a disease of dogs caused by cigar shaped parasite Demodex canis. This mite, a normal inhabitant of canine skin, is found in larger than normal numbers in diseased dogs.

Localized Demodicosis

Typically develops on the head and forelimbs and less commonly on the trunk as one or more patches of alopecia. There may be mild erythema and scaling and later hyperpigmentation develops. The majority of cases occur in pups 3 to 6 months old and spontaneous recovery without treatment is usual up to 10% of cases.

Generalized Demodicosis

It is severe skin condition frequently associated with generalized deep pyoderma, which may be fatal without extensive treatment; such cases have been shown to have profound T-cell suppression.

Lesions of this type of demodicosis are most marked on the head and legs but quickly spread to other areas. There is severe crusting, scaling and alopecia. Even oozing out of pus is also being noticed in severe infection.

In acute cases there may be extensive erythema hence the old term- "Red mange". As lesions became chronic this erythema is replaced by stale hyperpigmentation.

Juvenile demodicosis is the term used to describe case beginning before the age group of two years, while adult on set demodicosis occurs at any age after two years. Juvenile onset demodicosis is more common and has more favorable prognosis and the adult on set form may be associated with serious underlying systemic, possibly immunosuppressive diseases.

In demodicosis with pus, the lesions may be confined to feet. There may be swelling erythema and purulent infection of the feet in acute cases, and thickened hyper pigmentation of skin with alopecia in chronic cases.

Diagnosis

Skin examination is the main diagnostic test in demodicosis. Affected skin should be squeezed and then deep scrapings are performed. Microscopic examination revealed large number of mites and eggs.

Treatment

Most case of localized demodicosis regress spontaneously. About 10% of these cases developed the generalized form. General advice is given regarding feeding and management of the dog. Suitable medicated shampoo is also helpful to get rid of this disease.

Ivermectin @ 200 mcg per kg s/c or Amitraz solution 5% w/v are found to be effective.

Prevention

Animals that have generalized demodicosis or have produced pups that have developed demodicosis should not be used for breeding. Entire females or males in these categories should be neutered because tendency to develop demodicosis is inherited and secondly it prevents the relapse of the condition that may occur shortly after estrus.

You need to pay special attention to any occurrences of Demodicosis in a dog before you get tempted by any ad of dog for sale while you are thinking of getting a pet dog for yourself. The condition can occur in virtually any dog breed and not even a toy dog can be exempted.