Murine acariasis is commonly caused by Myocoptes musculinus. Is found on the hair shafts and skin surface over the flanks and rump in low numbers, and are distributed over the entire dorsum in high numbers. Usually no clinical signs are observed. Pathologic changes due to fur mite infestation include lymphadenopathy, hypergammaglobulinemia, secondary amyloidosis, lymphocytopenia, and splenic hypertrophy. Clinical manifestations vary from none to severe dermatitis with ulceration and pyoderma, depending on mouse strain and the species of mite, with M. musculi more commonly causing clinical disease.