Parasites of the Brush-Tailed Rock-Wallaby (Petrogale Penicillata)

Abstract

The brush-tailed rock-wallaby (Petrogale penicillata) is listed as vulnerable on the International Union for Conservation of Nature (IUCN) Red List of Threatened Species. Parasitic diseases have been proposed as possible contributing factors to the decline of the species, but very little is known about the effects of parasites on this host. This study determined the antibody prevalence of the protist Toxoplasma gondii in a wild brush-tailed rock-wallaby population from three neighboring colonies in southeast Queensland, Australia. Fecal egg and oocyst count, tick count, severity of skin rash, and presence of lice and microfilariae were also monitored during four or five trapping periods over 1 yr. Antibodies against T. gondii were detected in 5% of animals (3/64). Fecal egg and oocyst counts were highly variable, but fecal egg counts were lower in subadult animals relative to adults. Neither fecal egg count nor oocyst count was associated with variation in blood variables or condition index, but a negative association between fecal egg count and oocyst count was observed. Microfilariae (Breinlia spelaea), lice (Heterodoxus octoseriatus), and skin lesions were seen more frequently during the November trapping period. A mite, Thadeua sp., was more likely to be detected in these skin lesions than in skin of unaffected wallabies. Tick (Ixodes holocyclus and Haemaphysalis bancrofti) counts also varied between trapping periods and were lowest in the April/May trapping period. This study provides the most detailed account to date of parasite burdens in a vulnerable macropodid, but no clear evidence emerged linking parasites to adverse impact on the host.

Western Australian Marsupials Are Multiply Infected with Genetically Diverse Strains of Toxoplasma gondii

“…In this study, we found that of 16 macropod marsupials of three different species inhabiting a defined geographic area in the arid rangelands of Western Australia, all were infected. This is much greater than the prevalence found in three serological studies on macropods in different areas of Australia; 8.5% among Macropus rufogriseus and Thylogale billardierii in Tasmania [22], 15.5% and among Macropus fuliginosus in south western Australia [23] and 5% among Petrogale penicillata in southeast Queensland [24]. This suggests the need for serological studies on a larger sample of macropods from our study site, to determine whether our results are really reflective of a higher prevalence of T. gondii in this region.…”

Recent aspects on epidemiology, clinical disease, and genetic diversity of Toxoplasma gondii infections in Australasian marsupials

“…Toxoplasma gondii antibodies (MAT, 1:40) were detected in 3 out of 64 (4.6%) brush-tailed rock wallaby in Queensland, Australia [ 25 ].…”

Quantifying parasite presence in relation to biological parameters of harbour porpoises Phocoena phocoena stranded on the Dutch coast

“…For terrestrial mammals, extensive descriptions of lesions and diseases attributed to parasite presence are available and some parasites are even considered to regulate host populations (e.g. Gulland 1992, Nettles et al 2002, Barnes et al 2010). Much less is known about parasites in marine mammals (Lehnert et al 2010) and existing studies have con-centrated primarily on parasite taxonomy (Dougherty 1949, Arnold & Gaskin 1975 or directly parasiterelated pathology (Dailey & Stroud 1978, Faulkner et al 1998, Jepson et al 2000.…”