Molecular detection and characterisation of Toxoplasma gondii in eastern barred bandicoots (Perameles gunnii) in Victoria, Australia

Abstract

Australian marsupials are particularly susceptible to Toxoplasma gondii, an introduced zoonotic protozoan parasite. Molecular diagnostic methods are a highly specific approach for the detection of parasitic infections such as T. gondii. Importantly, molecular methods are useful for the characterisation of T. gondii to understand the genetic diversity of the parasite. The eastern barred bandicoot (Perameles gunnii) is a small native marsupial species classified as Critically Endangered. Although the species has previously been described as highly susceptible to infection with T. gondii, there is currently no information on the genotypes occurring in this species. This study employed qPCR for the detection of T. gondii in opportunistically obtained tissue samples from eastern barred bandicoot carcasses (n = 113) from Victoria, followed by determination of genotype using a DNA sequence-based virtual restriction fragment length polymorphism (RFLP) method. Overall, 19.5 % of the samples were positive for T. gondii using qPCR. The RFLP analysis revealed the dominance of T. gondii type II while a type II-like genotype was found in two isolates. This is the first study to provide information on prevalent genotypes of T. gondii in eastern barred bandicoots. Epidemiological studies of definitive and intermediate hosts, including further genotyping, are recommended to better understand T. gondii epidemiology for the successful recovery of eastern barred bandicoots in Australia.