Klossiella quimrensis (Apicomplexa: Klossiellidae) causes renal coccidiosis in western barred bandicoots Perameles bougainville (Marsupialia: Peramelidae) in Western Australia

First report on the prevalence of Klossiella muris in Mus musculus for S. Miguel Island - Azores (Portugal)

Klossiella is a genus of apicomplexan coccidian parasites with a global distribution, whose members typically infect the renal tissue of a wide variety of vertebrate hosts with a high level of host specificity. The presence of this parasite has been previously associated with kidney inflammatory processes. To our knowledge, this is the first report on the prevalence of Klossiella muris in the house mouse (Mus musculus) in Portugal (São Miguel Island - Azores). The prevalence of K. muris was determined through histopathological examination of renal tissue collected during necropsy of 130 mice captured between the years of 2011-2019. K. muris was diagnosed in 45.38% (CI₉₅: 40.9-85.4) of the examined mice. Infection with this parasite was associated with mild to severe kidney inflammation, assessed by the presence of inflammatory processes in the renal cortex and medulla. CAPSULE: First record on coccidiosis caused by infection of Klossiella muris in Mus musculus in Portugal.

Wildlife parasitology in Australia: past, present and future

Wildlife parasitology is a highly diverse area of research encompassing many fields including taxonomy, ecology, pathology and epidemiology, and with participants from extremely disparate scientific fields. In addition, the organisms studied are highly dissimilar, ranging from platyhelminths, nematodes and acanthocephalans to insects, arachnids, crustaceans and protists. This review of the parasites of wildlife in Australia highlights the advances made to date, focussing on the work, interests and major findings of researchers over the years and identifies current significant gaps that exist in our understanding. The review is divided into three sections covering protist, helminth and arthropod parasites. The challenge to document the diversity of parasites in Australia continues at a traditional level but the advent of molecular methods has heightened the significance of this issue. Modern methods are providing an avenue for major advances in documenting and restructuring the phylogeny of protistan parasites in particular, while facilitating the recognition of species complexes in helminth taxa previously defined by traditional morphological methods. The life cycles, ecology and general biology of most parasites of wildlife in Australia are extremely poorly understood. While the phylogenetic origins of the Australian vertebrate fauna are complex, so too are the likely origins of their parasites, which do not necessarily mirror those of their hosts. This aspect of parasite evolution is a continuing area for research in the case of helminths, but remains to be addressed for many other parasitic groups.

Transcriptome sequencing of the long-nosed bandicoot (Perameles nasuta) reveals conservation and innovation of immune genes in the marsupial order Peramelemorphia

Bandicoots are omnivorous marsupials of the order Peramelemorphia. Conservation concerns and their unique biological characteristics suggest peramelomorphs are worthy research subjects, but knowledge of their genetics and immunology has lagged behind that of other high-profile marsupials. Here, we characterise the transcriptome of the long-nose bandicoot (Perameles nasuta), the first high-throughput data set from any peramelomorph. We investigate the immune gene repertoire of the bandicoot, with a focus on key immune gene families, and compare to previously characterised marsupial and mammalian species. We find that the immune gene complement in bandicoot is often conserved with respect to other marsupials; however, the diversity of expressed transcripts in several key families, such as major histocompatibility complex, T cell receptor μ and natural killer cell receptors, appears greater in the bandicoot than other Australian marsupials, including devil and koala. This transcriptome is an important first step for future studies of bandicoots and the bilby, allowing for population level analysis and construction of bandicoot-specific immunological reagents and assays. Such studies will be critical to understanding the immunology and physiology of Peramelemorphia and to inform the conservation of these unique marsupials.

KLOSSIELLA DULCIS N. SP. (APICOMPLEXA: KLOSSIELLIDAE) IN THE KIDNEYS OF PETAURUS BREVICEPS (MARSUPIALIA: PETAURIDAE)

Two cases of renal klossiellosis were diagnosed by histopathology in pet sugar gliders (Petaurus breviceps). In both cases, parasites were associated with tubular dilation and mild interstitial nephritis. Rare schizonts were seen in the proximal convoluted renal tubular epithelium, whereas all other life cycle stages were found within distal convoluted tubule cells or the urinary space of the structures distal to the loop of Henle. Conventional optical and transmission electron microscopies were used to assess the life stages of the parasite. The morphologic characteristics and measurements observed differ from those of previously described species of Klossiella infecting marsupial hosts, and the name Klossiella dulcis n. sp. is hereby proposed. This is the first report of a Klossiella sp. infection in Petaurus breviceps .

The biology and palaeontology of the Peramelemorphia: a review of current knowledge and future research directions

Bandicoots and bilbies (Marsupialia : Peramelemorphia) represent the dominant omnivorous clade of Australasian marsupials and, as ground-dwelling, small- to medium-sized mammals, have not fared well in the 200 years since European settlement. Unlike large or charismatic marsupial species, the cryptic nature of bandicoots and bilbies tends to keep them out of the public eye, at a time when public interest plays a significant role in conservation efforts. The inconspicuous ‘rat-like’ appearance of many bandicoots and a generalist ecological strategy belie a complex biology of adaptive traits and evolutionary diversity. For a few species these biological traits have enabled them to make use of urban environments. In the main, however, peramelemorphians are facing ongoing pressure from introduced predators and human impacts. Basic biological information for many species, particularly those from New Guinea, is still lacking. In this review, we examine advances in the knowledge of the biology of this group over the past 25 years including anatomical, physiological and ecological studies. We also provide a comprehensive review of the fossil records of bandicoots in order to provide an up-to-date platform for future studies. From this work, it is clear that there is still much to be done regarding the taxonomy and biology of these animals before a more detailed understanding of the evolutionary history of this group can be elucidated.

Coccidial dispersion across New World marsupials: Klossiella tejerai Scorza, Torrealba & Dagert, 1957 (Apicomplexa: Adeleorina) from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) (Mammalia: Didelphimorphia)

Klossiella tejerai Scorza, Torrealba & Dagert, 1957 is a primitive coccidian parasite reported from the New World marsupials Didelphis marsupialis (Linnaeus) and Marmosa demerarae (Thomas). The current work describes K. tejerai from the Brazilian common opossum Didelphis aurita (Wied-Neuwied) in Southeastern Brazil, evidencing the coccidial dispersion across opossums of the same family. The sporocysts recovered from urine samples were ellipsoidal, 20.4 × 12.7 µm, with sporocyst residuum composed of scattered spherules and c.13 sporozoites per sporocyst, with refractile bodies and nucleus. Macrogametes, microgametes, sporonts, sporoblasts/sporocysts were identified within parasitophorous vacuoles of epithelial cells located near the renal corticomedullary junction. Didelphis marsupialis should not have transmitted K. tejerai to D. aurita because they are not sympatric; however M. demerarae is sympatric with D. marsupialis and D. aurita. Therefore, D. aurita becomes the third host species for K. tejerai in South America.

Hepatic intranuclear glycogen inclusions in western barred bandicoots (Perameles bougainville)

The western barred bandicoot, Perameles bougainville, is an endangered Australian marsupial species. Routine histology of liver samples collected at necropsy from 19 of 20 (95%) western barred bandicoots revealed the sporadic to common occurrence of abnormal hepatocyte nuclei characterized by margination of chromatin and concomitant central pallor. Some abnormal hepatocyte nuclei were mildly to markedly enlarged and irregularly shaped. Periodic acid-Schiff reagent stained 131 of 142 (92%) of these abnormal hepatocyte nuclei. Positive staining was completely eliminated by diastase pretreatment. Transmission electron microscopy revealed that abnormal hepatocyte nuclei with marginated chromatin did not contain viral particles. Rather, glycogen beta-particles and alpha-rosettes were identified within some abnormal hepatocyte nuclei. Glycogen intranuclear inclusions were an incidental finding in western barred bandicoot hepatocytes.