Theileria gilberti n. sp. (Apicomplexa: Theileriidae) in the Gilbert's Potoroo (Potorous gilbertii)

Abstract

The morphology and genetic characterisation of a new species of piroplasm identified in the blood of the Gilbert's potoroo (Potorous gilbertii) from the Two Peoples Bay Nature Reserve near Albany, Western Australia, is described from blood and tissue samples from 16 Gilbert's potoroos. Microscopy of blood showed these parasites are highly pleomorphic with a mean length of 1.8 mum and mean width of 0.85 mum. Phylogenetic analysis of 18S rRNA sequence data identified the piroplasm as a new species of Theileria that is closely related to other Australian marsupial piroplasm species. Based on biological and molecular data, it is proposed that the parasite from Gilbert's potoroo be given the name Theileria gilberti n. sp.

Morphological and molecular characterization ofTrypanosoma copemanin. sp. (Trypanosomatidae) isolated from Gilbert's potoroo (Potorous gilbertii) and quokka (Setonix brachyurus)

“…(Lee et al 2009). An earlier study by Cox (1977) showed that piroplasms enhance and prolong trypanosome infections particularly in stercorarian-transmitted trypanosomes and generally occur together in the wild.…”

A high prevalence of Theileria penicillata in woylies (Bettongia penicillata)

“…in Australian monotreme and marsupial hosts is relatively high; Collins et al (1986) found 53/54 (98%) platypuses trapped in New South Wales were infected with T. tachyglossi and a similar prevalence, 16/16 (100%), was reported for T. gilberti in Gilbert's potoroos in Western Australia (Lee et al, 2009). In our study, like that of Lee et al (2009), we also utilized PCR analysis to detect piroplasm infection rates; this method confirmed the high prevalence of infection in all but the Warrup site (Table 1) and although only a subset of samples were screened by microscopy (32/153), all the microscopy positives corresponded with the PCR positives. The results of the present study suggest that the parasite is widespread among woylies and can probably be considered to be endemic in this host species in these localities in Western Australia.…”

“…Although little is known about the clinical effects of piroplasm infections in marsupials, high parasitaemias appear to be well tolerated in some species (e.g. the Gilbert's potoroo, Potorous gilbertii) and have little pathological effect (Lee et al, 2009), yet in others, such as the agile antechinus (Antechinus agilis), babesiosis has been reported as a cause of anaemia in moribund males undergoing semelparity ( Cheal et al, 1976 andBarker et al, 1978).…”

“…in native Australian mammals: Theileria tachyglossi in the echidna (Tachyglossus aculeatus) (Priestley, 1915); Theileria peramelis in the northern brown bandicoot (Isoodon macrourus) (originally reported as Isoodon obesulus), the long nosed bandicoot (Perameles nasuta) and the long nosed potoroo (Potorous tridactylus), Theileria ornithorhynchi in the platypus (Ornithorhynchus anatinus) (Mackerras, 1959); Theileria gilberti in Gilbert's potoroo (P. gilbertii) (Lee et al, 2009); Theileria brachyuri in the quokka (Setonix brachyurus), Theileria fuliginosa in the western grey kangaroo (Macropus fuliginosus), and Theileria penicillata in the woylie (B. penicillata) (Clark and Spencer, 2007). Unnamed piroplasm species (presumed Theileria spp.)…”

“…Unnamed piroplasm species (presumed Theileria spp.) have been found in the long-nosed bandicoot (P. nasuta) and long-nosed potoroo (P. tridactylus) ( Clark et al, 2004 andLee et al, 2009), and, recently, in the burrowing bettong (boodie) (Bettongia lesueur) (Paparini et al, 2012). There are at least two named Babesia spp.…”