MICROSPORIDIA (ENCEPHALITOZOON-CUNICULI) IN WILD RABBITS IN AUSTRALIA

Objective To determine the prevalence of infection with Encephalitozoo n cuniculi in wild rabbit populations in Western Australia, and to iso late the organism from seropositive rabbits. Design Serological screen ing of wild and clinically affected domestic rabbit populations. Sampl e population Eight-one wild rabbits from south-western Western Austral ia and 29 laboratory rabbits. Procedure Indirect immunofluorescence an tibody technique and in-vitro amplification of parasite isolates in fi broblast cultures. Results Of the 81 wild rabbits and 29 laboratory ra bbits, 20 and 22 respectively, had antibodies to E cuniculi. E cunicul i from the urine of one seropositive laboratory rabbit and from brain and kidney tissues of eight and five seropositive laboratory and wild rabbits respectively were isolated in fibroblast cultures. Conclusion E cuniculi infection has been shown for the first time to be prevalent in wild rabbits in Australia. Techniques have been developed for the isolation and culture of the causative agent. Comparative studies can now be undertaken to determine risk factor for clinical disease in dom estic rabbits and the relationship among E cuniculi isolates from wild and domestic rabbits.