Demodicosis in a captive African straw-coloured fruit bat (Eidolon helvum)

Demodicosis is most frequently observed in the domestic dog (Canis familiaris), but it has rarely been reported in bats (Chiroptera). The overpopulation of Demodex spp. that causes dermatological changes is generally associated with a compromised immune system. We describe the gross and histological features of generalized demodicosis in an adult female African straw-coloured fruit bat (Eidolon helvum) drawn from a captive research colony. The histology of the lesions revealed comedones and follicular infundubular cysts harbouring numerous Demodex spp. mites, eliciting a minimal inflammatory response in the adjacent dermis. The histological examination of a full set of tissues did not reveal clear evidence of immunosuppression, although a clinical history of recent abortion and possible stressors due to captivity could be considered risk factors for the demodicosis. Attempts to determine the Demodex species using PCR on DNA extracted from the formalin fixed paraffin embedded tissue failed. This is the first clinical and histological description of demodicosis in Eidolon helvum.