Diseases of the eastern barred bandicoot (Perameles gunnii) with special reference to toxoplasmosis and the marsupial immune system

The reasons for the population decline of the marsupial the Eastern Barred Bandicoot, Perameles gunnii, in Tasmania, and the probable role of their susceptibility to protozoan diseases such as Toxoplasma gondii remain elusive. The pathological hallmarks of the disease have been extensively investigated in other animal species and although some species are more vulnerable to toxoplasmosis than others, the reason for marsupial vulnerability remains to be fully defined. This thesis has sought to address these and other factors that might be associated with the relationship between the marsupial, its microbial and parasitic diseases, ecological surroundings and immune system. Secondly, it was essential to examine the current disease status of P. gunnii in relation to its zoonotic potential in the Tasmanian setting. Finally, it was necessary to attempt to investigate the immunological status of this animal. The major conclusions from these investigations were that P. gunnii is extremely susceptible to even low doses of T. gondii oocysts. The development of clinical disease is rapid, with high morbidity and mortality. The species appears to be susceptible to other Apicomplexan species including Hepatozoon sp., and the flagellate Giardia. The close association of P. gunnii with humans and the infringement of humans into their habitat makes this marsupial vulnerable to trauma, predation, shelter and food deprivation, and exacerbation of current parasitic and microbial diseases. In summary, this study further clarifies the relationship between humans, P. gunnii and parasite and the possible zoonotic potential that exists within Tasmania.