Verminous encephalitis apparently caused by the filarioid nematode Chandlerella quiscali in emus (Dromaius novaehollandiae).

Verminous encephalitis attributed to Chandlerella quiscali was diagnosed in a flock of emus (Dromaius novaehollandiae). Clinically affected birds showed torticollis and progressive ataxia. Filarioid parasites with morphological characteristics resembling C. quiscali were identified in one case. Histologic lesions in the brain and spinal cord consisted of mild to moderate perivascular cuffing and scattered areas of variable mild necrosis. Parasites observed within the parenchyma of the brain and spinal cord often were not associated with either necrosis or an inflammatory reaction. Ivermectin administered subcutaneously at 4-week intervals at a dose rate of 200 micrograms/kg body weight appeared to prevent clinical signs in flocks in the presumed endemic area.