Etiology:   Demodex criceti and Demodex aurati are mange mites of gerbils.

Incidence:  Mange mites are occasionally found on gerbils.

Transmission:  Transmission occurs by direct contact.

Distribution:

Demodex criceti inhabits pilosebaceous epidermal pits.

Demodex aurati inhabits the hair follicles.

Both species are commonly found infesting the same animal.

Clinical Signs:  Infection often occurs without clinical signs. Rough hair coat, alopecia or scaly dermatitis may develop with predisposing factors such as malnutrition, aging or systemic disease. Lesions generally occur over the back and rump (A.). D. aurati is considered more pathogenic than D. criceti.

Diagnosis:Diagnosis can be made by performing skin scrapings at the edges of affected areas for D. criceti and histopathology for D. aurati.

Diagnostic Morphology: Mites are bullet-shaped with 4 pairs of short, stubby legs, small mouthparts and no setae. D. criceti (B.) has a shorter, blunter posterior than that of D. aurati (C.).