Publications

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genetic variation in austrostrongylus thylogale johnston & mawson, 1940 (nematoda: trichostrongylida) from the tammar wallaby, notamacropus eugenii (gray), and the quokka, setonix brachyurus (quoy & gaimard) (marsupialia: macropodidae) in australia.australian marsupials harbour a diverse array of helminth parasites. despite current attempts to assess the extent of this diversity in macropodid hosts, it has been suggested that unique parasite fauna of australian wildlife is difficult to document comprehensively due to the common occurrence of cryptic species. this paper assessed genetic variation within austrostrongylus thylogale johnston & mawson, 1940 from the tammar wallaby, notamacropus eugenii (gray), and the quokka, setonix brachyurus ...202032171333
isolation of cryptococcus neoformans var. grubii (serotype a) and c. magnus from the nasal lining of free-ranging quokkas (setonix brachyurus).cryptococcus species are environmental yeasts, with a worldwide distribution and remarkable environmental adaptation. although many species do not cause disease, c. neoformans and c. gattii are causative agents of cryptococcosis, a life threatening infection and a significant public health problem worldwide. infection especially affects immunocompromised animals and humans. in wildlife, cryptococcosis appears to be more prevalent in captive populations. the objective of this study was to assess ...202032935332
salmonella in free-ranging quokkas (setonix brachyurus) from rottnest island and the mainland of western australia.salmonella is a genus of gram-negative, motile, and facultative anaerobic bacteria with a worldwide distribution that contaminates multiple substrates (vegetation, food, soil, and water) and inhabits the gastrointestinal tract of birds, reptiles, and mammals, including humans. rottnest island is a popular tourist destination and is abundantly inhabited by quokkas (setonix brachyurus), a charismatic small wallaby. current data on the association between salmonella and quokkas on rottnest island a ...202032244325
eimeria tamimi sp. n. (apicomplexa: eimeriidae) from the rock hyrax (procavia capensis jayakari) in central saudi arabia.faecal samples from the rock hyrax (procavia capensis jayakari thomas) were collected from the ibex reserve in central saudi arabia. eimerian oocysts, which are believed to represent a new species described here as eimeria tamimi sp. n., were detected in 40 out of 93 samples. oocysts were fully sporulated in 24-48 hours at 25 ± 2 °c. sporulated oocysts of e. tamimi sp. n. were ovoid, measuring 35-42 × 19-25 μm (39 × 23 μm), a length/width ratio 1.5-2 (1.7). oocyst wall was bilayered and measured ...202032075950
haematology and blood chemistry in free-ranging quokkas (setonix brachyurus): reference intervals and assessing the effects of site, sampling time, and infectious agents.quokkas (setonix brachyurus) are small macropodid marsupials from western australia, which are identified as of conservation concern. studies on their blood analytes exist but involve small sample sizes and are associated with very little information concerning the health of the animals. blood was collected from free-ranging quokkas from rottnest island (n = 113) and mainland (n = 37) western australia, between september 2010 and december 2011, to establish haematology and blood chemistry refere ...202032941511
new species and new records of species of cloacina von linstow, 1898 (nematoda: strongylida) parasitic in the western scrub wallaby, notamacropus irma (jourdan) (marsupialia: macropodidae) from western australia.the helminth parasites of the western scrub wallaby or black-glove wallaby, notamacropus irma (jourdan) which occurs in western australia are relatively poorly documented. six new species of the strongyloid genus cloacina von linstow, 1898 (strongylida: chabertiidae) are described namely c. asymmetrica n. sp., c. brazellei n. sp., c. harriganae n. sp., c. hobbsi n. sp., c. middletoni n. sp. and c. woodi n. sp. a redescription of c. laius beveridge, 1999 from the same host species is included. mo ...201931111307
sequence analyses at mitochondrial and nuclear loci reveal a novel theileria sp. and aid in the phylogenetic resolution of piroplasms from australian marsupials and ticks.the order piroplasmida encompasses two main families: babesiidae and theileriidae, containing tick-borne pathogens of veterinary and medical importance worldwide. while only three genera (babesia, cytauxzoon and theileria) comprising piroplasm parasites are currently recognised, phylogenetic studies at the 18s rrna (18s) gene suggest that these organisms represent at least ten lineages, one of which comprises the relatively unique and highly diverse theileria spp. from australian marsupials and ...201931851687
the effects of zoo visitors on quokka (setonix brachyurus) avoidance behavior in a walk-through exhibit.the behavior of zoo animals may be influenced by visitors, with possible implications on animal welfare. we examined the effects of the presence of visitors on the presence and visibility of free-ranging quokkas (setonix brachyurus) in preferred areas of a walk-through enclosure at melbourne zoo, australia. in a controlled experiment, two visitor treatments were randomly imposed: (1) enclosure open to visitors as normal ("open") and (2) enclosure closed to visitors ("closed"). treatments were im ...201829992613
quokka: a comprehensive tool for rapid and accurate prediction of kinase family-specific phosphorylation sites in the human proteome.kinase-regulated phosphorylation is a ubiquitous type of post-translational modification (ptm) in both eukaryotic and prokaryotic cells. phosphorylation plays fundamental roles in many signalling pathways and biological processes, such as protein degradation and protein-protein interactions. experimental studies have revealed that signalling defects caused by aberrant phosphorylation are highly associated with a variety of human diseases, especially cancers. in light of this, a number of computa ...201829947803
the influence of stimulus valence on confirmation bias in children.the aim of the present study was to replicate our previous study and to further examine the relation between fear and positive and negative confirmation bias in children.201727423221
a state of non-specific tension in living matter? stress in australian animals.evidence of stress responses in australian animals is reviewed through a series of case studies involving desert frogs and lizards, small carnivorous marsupials, desert wallabies, a dwarf kangaroo species, the quokka wallaby and a small nectarivorous bird. an operational definition of stress as "the physiological resultant of demands that exceed an animal's homeostatic capacities" is used to identify instances of stress responses in the field, and to gauge their intensity. clear evidence of stre ...201726449159
speciation in the genus cloacina (nematoda: strongylida): species flocks and intra-host speciation.sequences of the first and second internal transcribed spacers (its1 + its2) of nuclear ribosomal dna were employed to determine whether the congeneric assemblages of species of the strongyloid nematode genus cloacina, found in the forestomachs of individual species of kangaroos and wallabies (marsupialia: macropodidae), considered to represent species flocks, were monophyletic. nematode assemblages examined in the black-striped wallaby, macropus (notamacropus) dorsalis, the wallaroos, macropus ...201728697818
curvature reduces bending strains in the quokka femur.this study explores how curvature in the quokka femur may help to reduce bending strain during locomotion. the quokka is a small wallaby, but the curvature of the femur and the muscles active during stance phase are similar to most quadrupedal mammals. our hypothesis is that the action of hip extensor and ankle plantarflexor muscles during stance phase place cranial bending strains that act to reduce the caudal curvature of the femur. knee extensors and biarticular muscles that span the femur lo ...201728348929
molecular characterization of native australian trypanosomes in quokka (setonix brachyurus) populations from western australia.the quokka, setonix brachyurus, is a vulnerable, small marsupial endemic to western australia. blood samples were collected from quokkas from three different geographical locations; two peoples bay, bald island and rottnest island. the overall prevalence of trypanosomes by nested pcr at the 18s ribosomal rna gene was 57.3% (63/110) with prevalences of 91.4%, 85.3% and 4.9% respectively for two peoples bay, bald island and rottnest island. phylogenetic analysis conducted on 47 18s pcr positives i ...201626697991
investigation of the morphological diversity of the potentially zoonotic trypanosoma copemani in quokkas and gilbert's potoroos.trypanosomes are blood-borne parasites that can cause severe disease in both humans and animals, yet little is known of the pathogenicity and life-cycles of trypanosomes in native australian mammals. trypanosoma copemani is known to be infective to a variety of australian marsupials and has recently been shown to be potentially zoonotic as it is resistant to normal human serum. in the present study, in vivo and in vitro examination of blood and cultures from australian marsupials was conducted u ...201526160545
the innate resistance of trypanosoma copemani to human serum.trypanosoma copemani is known to be infective to a variety of australian marsupials. characterisation of this parasite revealed the presence of stercorarian-like life-cycle stages in culture, which are similar to t. rangeli and t. cruzi. the blood incubation infectivity test (biit) was adapted and used to determine if t. copemani, like t. cruzi and t. rangeli, has the potential to grow in the presence of human serum. to eliminate any effects of anticoagulants on the complement system and on huma ...201525816975
eimeria collieie n. sp. (apicomplexa:eimeriidae) from the western long-necked turtle (chelodina colliei).a new species, eimeria collieie n. sp., is described from the western long-necked turtle (chelodina colliei). sporulated oocysts (n = 35) are spherical to subspherical, with colourless single layer oocyst wall, 0.6 ± 0.2 (0.4-0.7) µm thick. oocyst with elongated ellipsoid sporocysts. oocyst length, 29.8 ± 0.4 (28.2-31.0) µm; oocyst width, 29.4 ± 0.3 (28.0-30.8) µm; oocyst length/width (l/w) ratio, 1.0 ± 0.03 (1.0-1.05). micropyle, oocyst residuum and polar granule were absent. sporocysts with sp ...201525917644
fear-related confirmation bias in children: a comparison between neutral- and dangerous-looking animals.the purpose of this study was to examine confirmation bias in children without explicitly inducing fear. eighty non-clinical children (7-13 years) were shown pictures of a neutral animal (quokka) and two dangerous-looking animals (aye aye and possum). for each animal, levels of perceived fear, threat and request for additional threatening or non-threatening information were obtained. a behavioral approach test (bat) was included as behavioral measure of fear. the results indicated that the aye a ...201525096507
further characterisation of two eimeria species (eimeria quokka and eimeria setonicis) in quokkas (setonix brachyurus).the identification and characterisation of novel eimeria species has largely been based on sporulated oocyst and sporocyst morphology, the host species and the geographical range. variation in the size and shape of eimeria oocysts across their host range however, make the identification and characterisation of novel species using traditional methodologies alone problematic. the use of molecular markers and phylogenetic analysis has greatly advanced our ability to characterise eimeria species and ...201424508502
the in vitro response to phytohaemagglutinin (pha) of leucocytes from intact and thymectomized quokkas. 20144143969
identification of novel babesia and theileria genotypes in the endangered marsupials, the woylie (bettongia penicillata ogilbyi) and boodie (bettongia lesueur).piroplasms, which include the genera theileria and babesia, are blood-borne parasites transmitted mainly by tick vectors. relatively little is known about their prevalence and clinical impact in australian marsupials. in the present study the occurrence and molecular phylogeny of these parasites were studied in both wild and captive marsupials from western australia (wa) and queensland (qld). blood samples were screened by microscopy and molecular methods, using pcr and dna sequencing of the 18s ...201222433913
vector of trypanosoma copemani identified as ixodes sp.summarya total of 41 ticks were collected from 15 quokkas on bald island and 2 ticks from a gilbert's potoroo from two peoples bay. three species of ixodid ticks ixodes australiensis, ixodes hirsti and ixodes myrmecobii were identified on the quokkas known to have a high prevalence of trypanosoma copemani. tick faeces from ticks isolated from 8 individual quokkas and a gilbert's potoroo were examined with one identified as positive for trypanosomes. faecal examination revealed trypanosomes simil ...201121518469
molecular characterization of blastocystis isolates from zoo animals and their animal-keepers.blastocystis is an enteric protist and one of the most frequently reported parasitic infections in humans and a variety of animal hosts. it has also been reported in numerous parasite surveys of animals in zoological gardens and in particular in non-human primate species. pcr-based methods capable of the direct detection of blastocystis in faeces were used to detect blastocystis from various hosts, including non-human primates, australian native fauna, elephants and giraffes, as well as their ke ...201020089360
diversity of color vision: not all australian marsupials are trichromatic.color vision in marsupials has recently emerged as a particularly interesting case among mammals. it appears that there are both dichromats and trichromats among closely related species. in contrast to primates, marsupials seem to have evolved a different type of trichromacy that is not linked to the x-chromosome. based on microspectrophotometry and retinal whole-mount immunohistochemistry, four trichromatic marsupial species have been described: quokka, quenda, honey possum, and fat-tailed dunn ...201021151905
morphological and molecular characterization of trypanosoma copemani n. sp. (trypanosomatidae) isolated from gilbert's potoroo ( potorous gilbertii) and quokka ( setonix brachyurus).little is known of the prevalence and life-cycle of trypanosomes in mammals native to australia. native australian trypanosomes have previously been identified in marsupials in the eastern states of australia, with one recent report in brush-tailed bettongs (bettongia penicillata), or woylie in western australia in 2008. this study reports a novel trypanosoma sp. identified in blood smears, from 7 critically endangered gilbert's potoroos (potorous gilbertii) and 3 quokkas (setonix brachyurus) in ...200919416553
evolution of lactation: nutrition v. protection with special reference to five mammalian species.the evolutionary origin of the mammary gland has been difficult to establish because little knowledge can be gained on the origin of soft tissue organs from fossil evidence. one approach to resolve the origin of lactation has compared the anatomy of existing primitive mammals to skin glands, whilst another has examined the metabolic and molecular synergy between mammary gland development and the innate immune system. we have reviewed the physiology of lactation in five mammalian species with spe ...200819087365
compensatory and transneuronal plasticity after early collicular ablation.plasticity within the visual system was assessed in the quokka wallaby following unilateral superior collicular (sc) ablation at postnatal days (p) 8-10, prior to the arrival of retinal ganglion cell (rgc) axons. at maturity (p100), projections were traced from the eye opposite the ablation, and total rgc numbers were estimated for both eyes. ablations were partial (28-89% of sc remaining) or complete (0-5% of sc remaining). projections to the visual centers showed significant bilateral (p < 0.0 ...200717183539
functional respiratory morphology in the newborn quokka wallaby (setonix brachyurus).a morphological and morphometric study of the lung of the newborn quokka wallaby (setonix brachyurus) was undertaken to assess its morphofunctional status at birth. additionally, skin structure and morphometry were investigated to assess the possibility of cutaneous gas exchange. the lung was at canalicular stage and comprised a few conducting airways and a parenchyma of thick-walled tubules lined by stretches of cuboidal pneumocytes alternating with squamous epithelium, with occasional portions ...200717553103
cone topography and spectral sensitivity in two potentially trichromatic marsupials, the quokka (setonix brachyurus) and quenda (isoodon obesulus).the potential for trichromacy in mammals, thought to be unique to primates, was recently discovered in two australian marsupials. whether the presence of three cone types, sensitive to short- (sws), medium- (mws) and long- (lws) wavelengths, occurs across all marsupials remains unknown. here, we have investigated the presence, distribution and spectral sensitivity of cone types in two further species, the quokka (setonix brachyurus) and quenda (isoodon obesulus). immunohistochemistry revealed th ...200515888411
detour behavior in the quokka (setonix brachyurus).four quokkas (setonix brachyurus) were tested in their natural environment for the ability to progress around a barrier to a desired goal object (food). symmetrical and asymmetrical barriers were used with different lengths of side arm. three quokkas showed significant tendencies to progress either left or right around the barrier, though this laterality declined as the length of the side arm of the barrier was extended. one quokka showed no behavioral laterality and this animal was also the onl ...200415499677
studies of learning and problem solving in two species of australian marsupials.this article reviews the authors' recent work with two species of australian marsupials on several learning and conditioning experiments. the quokka (setonix brachyurus) is a cat-sized herbivorous wallaby that inhabits offshore islands around south-western australia. the fat-tailed dunnart (sminthopsis crassicaudata) is a mouse-sized carnivorous marsupial that inhabits much of inland australia. both species were successful in learning simple discriminations, learning sets and reversal sets. quok ...200415527864
morphometry and allometry of the postnatal marsupial lung development: an ultrastructural study.an utrastructural morphometric study of the postnatally remodelling lungs of the quokka wallaby (setonix brachyurus) was undertaken. allometric scaling of the volumes of the parenchymal components against body mass was performed. most parameters showed a positive correlation with body mass in all the developmental stages, except the volume of type ii pneumocytes during the alveolar stage. the interstitial tissue and type ii cell volumes increased slightly faster than body mass in the saccular st ...200314609519
numbers of neurons in the retinal ganglion cell layer of the rat do not change throughout life.there have been many assumptions made about neuronal loss in mammals due to aging. however, when we examined the retinal ganglion cell layer of a marsupial, the quokka, from 0.5 to 13.5 years of age, we found that the total neuron number did not decrease significantly even into extreme old age. the retinal area increased slowly throughout life, leading to a decrease in cell density. neuronal death in the rat retina has been assumed, since the cell density has been seen to fall with age. however, ...200314624063
morphometry and allometry of the postnatal lung development in the quokka wallaby (setonix brachyurus): a light microscopic study.the postnatally developing lungs of the quokka wallaby, setonix brachyurus, were investigated macroscopically and by light microscopic morphometry. lung, parenchymal and non-parenchymal volumes as well as the components of the latter two were analysed by regression analysis. the lungs comprised a single undivided left lung and a right lung with an adherent accessory lobe. septal tissue growth was most remarkable in the canalicular and saccular stages. between mid-canalicular stage and the saccul ...200312573880
configural learning in two species of marsupial (setonix brachyurus and sminthopsis crassicaudata).four experiments examined the ability of quokkas (setonix brachyurus) and fat-tailed dunnarts (sminthopsis crassicaudata) to solve 2 configural tasks: transverse and negative patterning. transverse patterning requires the simultaneous solution of 3 overlapping discrimination problems (a+ b-, b+ c-, c+ a-). both species could solve the nonoverlapping (elemental) version of this task (u+ v-, w+ x-, y+ z-), but only dunnarts solved the transverse patterning task. negative patterning requires condit ...200312856789
quokkas (setonix brachyurus) demonstrate tactile discrimination learning and serial-reversal learning.two male quokkas (setonix brachyurus: a herbivorous macropod marsupial) were trained to discriminate pairs of stimuli in the laboratory. quokkas indicated their choice by pulling on 1 of 2 simultaneously presented cords. the quokkas' discrimination abilities were tested on 6 tactile and 6 visual discrimination tasks. correct responses were rewarded with food. for both quokkas, all tactile tasks were learned to a criterion of 75% correct in up to 4 20-trial sessions. no visual task maintained cri ...200211930935
bait-delivered cabergoline for the reproductive control of the red fox (vulpes vulpes): estimating mammalian non-target risk in south-eastern australia.cabergoline (cab) is a potent dopamine agonist and an inhibitor of prolactin (prl). in red foxes (vulpes vulpes), a single oral dose of 100 microg kg(-1) cab can cause abortions and postnatal cub mortality from at least day 21 of the 52-day pregnancy. the abortifacient activity of cab is owing to the suppression of prl, which is essential for luteotrophic support in some eutherian species. postnatal cub mortality probably results from a reduction in the development of the mammary ductile system, ...200111999299
morphological analysis of the postnatally developing marsupial lung: the quokka wallaby.we investigated the events that take place during the postnatal morphogenesis of the lung of the quokka wallaby, setonix brachyurus, using the light microscope and both the scanning and transmission electron microscopes. the lung of term, newborn babies (joeys) at 3-days of postnatal life was at late canalicular stage and comprised large airways and tubules separated by thick mesenchymal interstitium. the tubules were lined by a low cuboidal epithelium but had few portions with true gas exchange ...200111241194
experimental eye enlargement in mature animals changes the retinal pigment epithelium.form deprivation has been shown to result in myopia in a number of species such that the eye enlarges if one eye is permanently closed at the time of eye opening. in the quokka wallaby, the eye grows slowly throughout life. after form deprivation, the eye enlarges by 1-1.5 years of age to the size of that in a 4-6-year-old animal and the number of multinucleated retinal pigment epithelial (rpe) cells in the enlarged retina remains much lower than would be expected in eyes of comparable size. her ...199910431911
number of neurons in the retinal ganglion cell layer of the quokka wallaby do not change throughout life.during adult life, the topography of the retinal pigment epithelium (rpe) of the quokka wallaby changes gradually. cells in peripheral retina enlarge in surface area while those in mid-temporal retina, adjacent to the area centralis, a high density region in the ganglion cell layer, decrease in area, implying that the tissue in this area is drawing together. we speculated that high ganglion cell densities in temporal regions might be maintained, in the face of cell loss due to aging, by this app ...199910456988
dopaminergic amacrine cells in the retina of the possum, trichosurus vulpecula.the common brush-tailed possum trichosurus vulpecula is a small diprotodont marsupial common to both urban and natural environments. this is the first analysis of the neurotransmitter content of its retinal cells and, as the possum is a nocturnal forager, it was appropriate to begin with the dopaminergic amacrine cells that form an essential link in the modulation of the rod pathways subserving nocturnal vision. these results were compared with those from another diprotodont, the marsupial walla ...19989682872
effects of cabergoline on reproduction in three families of australian marsupials.the effects of the prolactin inhibiting drug, cabergoline, on pregnant and lactating marsupials were investigated in four species from three diverse families: the tammar wallaby, macropus eugenii, the quokka, setonix brachyurus, the brushtail possum, trichosurus vulpecula, and the fat-tailed dunnart, sminthopsis crassicaudata. in tammar wallabies, 20 micrograms cabergoline kg-1 injected intramuscularly 1 day before expected birth did not alter the timing of parturition but neonates died within a ...19989713388
the effect of oestrus and the presence of pouch young on aerobic bacteria isolated from the pouch of the tammar wallaby, macropus eugenii.qualitative changes in the culturable, aerobic bacterial flora isolated from the tammar pouch have been documented over the period leading up to oestrus, at the time of anticipated birth and in absence and presence of pouch young of varying ages. in a group of 12 animals studied thirty species of aerobic bacteria were isolated. twenty five species were found in pouches with no pouch young, 9 in pouches with young less than 3 weeks of age and 9 in pouches containing older animals. gram positive o ...19989775355
anatomical comparison of the macaque and marsupial visual cortex: common features that may reflect retention of essential cortical elements.this study identifies fundamental anatomical features of primary visual cortex, area v1 of macaque monkey cerebral cortex, i.e., features that are present in area v1 of phylogenetically distant mammals of quite different lifestyle and features that are common to other regions of cortex. we compared anatomical constituents of macaque v1 with v1 of members of the two principal marsupial lines, the dunnart and the quokka, that diverged from the eutherian mammalian line over 135 million years ago. f ...19989786408
the effects of a transient increase in temperature on cell generation and cell death in the hippocampus and amygdala of the wallaby, setonix brachyurus (quokka).we examined the effects of a single exposure to a temperature elevation of 2 degrees c for a 2 h period on the developmental processes of cell division and cell death in the hippocampus and the amygdala of the quokka. animals aged postnatal day (p) 4045 were injected with tritiated (3h-) thymidine and then exposed to either 37 degrees c (normal) or 39 degrees c (+/-0.2 degrees c) in an incubator for a duration of 2 h. the young were then returned to the nipple and, after a period of 24 h, were s ...19989808303
transient axonal side branches in the developing mammalian optic nerve.optic axons were labelled with horseradish peroxidase to establish the presence of side branches and examine their distribution and morphology in the developing optic nerve of the quokka wallaby, setonix brachyurus, the cat and rat at stages when axon numbers are at their peak. in each species, three quarters of the axons were essentially straight and lacked side branches. the remaining axons took significantly longer paths and bore side branches, mostly at points where axons undulated or change ...19989394042
axon order in the visual pathway of the quokka wallaby.axon order throughout the visual pathway of the quokka wallaby (setonix brachyurus) was determined after localised retinal applications of the tracers dii and/or diasp. postnatal days (p) 22-90 were studied to encompass the development and refinement of retinal projections. order was essentially similar at all stages. axons entered the optic nerve head true to their sector of retinal origin. in the optic nerve, nasal and temporal axons continued to reflect their retinal origin, dominating, respe ...19989455896
development and cell generation in the hippocampus of a marsupial, the quokka wallaby (setonix brachyurus).development and cell generation in the hippocampus of the marsupial, the quokka wallaby, has been examined. cells in this brain region are similar in morphology to those in eutherian species, with predominantly pyramidal and granule cells. in the quokka, development of the hippocampus takes place postnatally; this region is first seen just after birth on postnatal day 1 (p1) as an out-pouching of the medial cortical wall into the lateral ventricle. the cornu ammonis (ca) region first appears at ...19979466706
changing topography of the rpe resulting from experimentally induced rapid eye growth.the retinal pigment epithelium (rpe) of the quokka wallaby. setonix brachyurus, grows and changes throughout life. to investigate factors that determine changes in the quokka rpe, we have examined topography of this tissue in experimentally enlarged eyes. unilateral eyelid suture was conducted at the time of normal eye opening, postnatal day (p) 110, and animals were examined at 1 or 1 1/2 years of age. the numbers and densities of rpe cells and the extent of multinucleation were compared with t ...19979194313
development of the lymphoid tissues of the tammar wallaby macropus eugenii.a study has been made of the development of four lymphoid tissues from birth to maturity in the tammar wallaby macropus eugenii--the cervical and thoracic thymus, lymph nodes and gut-associated lymphoid tissue (galt). the development of these tissues in the tammar wallaby is similar to that in two other marsupials, the quokka setonix brachyurus and the virginian opossum didelphis virginiana. lymphocytes were first detected in the cervical thymus of the tammar at day 2 post partum and in the thor ...19979208435
retinal pigment epithelium topography in the mature quokka, setonix brachyurus.in this paper we describe cell topography of the retinal pigment epithelium (rpe) for the mature marsupial wallaby, the quokka, setonix brachyurus. rpe topography was analysed in bleached and stained whole mounted retinae, sampling from the entire surface area. the mature adult quokka rpe has a distinct topography in terms of both cell density and the distribution of multinucleate cells. peripheral rpe demonstrates the lowest cell density and the greatest proportion of multinucleate cells. in an ...19968674516
development and ageing of the rpe in a marsupial, the quokka.we have previously shown that the mature adult quokka, aged between 8 and 15 years, has a distinct cell topography in the retinal pigment epithelium (rpe). we reported that the adult cell densities were high in central temporal retina and low in a peripheral band, adjacent to the ora serrata, a region with a concentration of multinucleate cells. in the present paper, we have studied the development of these features in order to understand how they mature, as well as to gain insight into regional ...19968759514
a new family of entodiniomorph protozoa from the marsupial forestomach, with descriptions of a new genus and five new species.a unique group of entodiniomorph protozoa was found in forestomach contents from quokka (setonix brachyurus), western grey kangaroo (macropus fuliginosus), red kangaroo (macropus rufus) and euro (macropus robustus erubescens). a new genus, macropodinium n.g., containing five new species, is described. three species are described from forestomach contents of the quokka: macropodinium baldense n. sp., macropodinium moiri n. sp. and macropodinium setonixum n. sp. a single species, macropodinium enn ...19968768432
retinal pigment epithelium and photoreceptor maturation in a wallaby, the quokka.cell generation and the early stages of maturation of the retinal pigment epithelium (rpe) and photoreceptors were examined in a marsupial, the quokka, setonix brachyurus. results are presented for animals aged up to postnatal day (p)250. rpe cell generation was studied by analysis of cell number from wholemounted retinae and by tritiated thymidine (3hthy) autoradiography in sectioned material. for 3hthy autoradiography, quokkas aged p1-p200 were injected with 3hthy and killed either 6-20 hours ...19968797156
development of the chiasm of a marsupial, the quokka wallaby.we have previously shown that the mature optic chiasm of a marsupial is divided morphologically into three regions, two lateral regions in which ipsilaterally projecting axons are confined and a central region containing only contralaterally projecting axons. by contrast, in the chiasms of eutherian (placental) mammals studied to date, there is no tripartite configuration. ipsilaterally and contralaterally projecting axons from each eye are mixed in the caudal nerve and in each hemichiasm and en ...19957499544
development of the visual cortex in a wallaby--phylogenetic implications.the visual cortex of one of the smallest macropod marsupials, a wallaby, the quokka setonix brachyurus, was examined at maturity and during development from postnatal day 1 to 150 in nissl-stained or golgi-stained sections. injections of horseradish peroxidase into the primary visual centres in adults identified cortical neurons projecting to these regions. the pattern of cell generation was determined by tritiated thymidine/autoradiography. the adult visual cortex was composed of the usual six ...19957796093
the complete primary structure of late lactation protein from quokka (setonix brachyurus).the complete primary structure of the late lactation protein from the milk of quokka (setonix brachyurus) is presented. the amino acid sequence was established by n-terminal sequence analysis of high-performance liquid chromatography purified intact protein and peptides isolated from chemical and enzymatic digests of the protein. the protein contains 158 residues including four cysteines. the sequence comparison with the tamar wallaby (macropus eugenii) late lactation protein shows only five dif ...19947832979
horizontal cells in the retina of the brush-tailed possum.most species of eutherian (placental) mammals examined have two types of horizontal cell, one is axonless and the other has a short axon. we have recently shown that a marsupial, the quokka wallaby, also has two types of horizontal cell and that the axonless cell in this species has unusual stubby processes that pass through the inner nuclear layer to reach the inner plexiform layer. in order to discover whether these descending processes are a feature of marsupials in general, i examined the mo ...19948013586
morphology and birth dates of horizontal cells in the retina of a marsupial.most eutherian (placental) mammals have two horizontal cell types; however, one type only has been seen in rodents. in order to assess whether one type of horizontal cell or two is a basic mammalian feature, we have examined the morphology of horizontal cells in a marsupial, the quokka wallaby, by golgi staining or horseradish peroxidase labelling. the birth dates of horizontal cells have also been determined by 3h-thymidine/autoradiography. there are two types of horizontal cell in the wallaby ...19948188858
adrenalectomy and steroid replacement in a small macropodid marsupial, the quokka (setonix brachyurus): metabolic and renal effects.contrary to previously accepted observations, the quokka (setonix brachyurus), a small macropodid marsupial, survival bilateral adrenalectomy indefinitely if injected with appropriate doses of cortisol and aldosterone, either singly or combined. normal behavior and plasma solute concentrations could be maintained indefinitely by daily i.m. injection of 0.2 mg cortisol acetate and 0.01 mg aldosterone/kg. plasma glucose concentration was maintained at the control value when the supplement containe ...19938504924
genetic, structural, and functional studies of a c3-like protein in the marsupial setonix brachyurus.a monospecific goat antiserum was prepared against a putative c3 protein (quc3) from serum of the western australian macropod setonix brachyurus (quokka) using the classical method previously used to produce antiserum against c3 from other mammalian species. sodium dodecyl sulphate-polyacrylamide gel electrophoretic analysis of reduced immunoprecipitated quc3 revealed two polypeptide chains with an estimated m(r) of 128,000 and 82,000, respectively--presumably reflecting subunit molecules simila ...19938136176
estradiol-17 beta secretion by the newly formed corpus luteum of a macropodid marsupial, the quokka (setonix brachyurus).the production of significant amounts of estradiol-17 beta from the 2-day-old corpus luteum of the macropodid marsupial, setonix brachyurus (quokka), was shown using an in vitro perifusion system. sliced corpora lutea and finely chopped extra-luteal ovarian tissue (cortex plus interstitial tissue) were perifused separately for 2 hr, in tandem for the next hour (with the perifusate from the ovarian tissue directed into the chamber containing the corpora lutea), and separately again for a further ...19921426945
quokka bites. the first report of bites from an australian marsupial.to describe the incidence and natural history of bites from the quokka, a small wallaby.19921453997
biphasic retinal neurogenesis in the brush-tailed possum, trichosurus vulpecula: further evidence for the mechanisms involved in formation of ganglion cell density gradients.we investigated cell generation in the retina of the brush-tailed possum (trichosurus vulpecula) by using tritiated (3h)-thymidine labelling of newly generated cells. animals aged between postnatal day (p) 5 and 85 each received a single injection of 3h-thymidine. following autoradiographic processing, maps of labelled cells were constructed from retinal sections. retinal cell generation takes place in two phases, the first is concluding in the retinal periphery at p53 as the second is seen to c ...19921469115
distinctive pattern of organisation in the retinofugal pathway of a marsupial: i. retina and optic nerve.the nasotemporal division in the retina and the pattern of crossed and uncrossed axons in the optic nerve were determined in an australian marsupial, a wallaby, setonix brachyurus (the quokka), following unilateral horseradish peroxidase injections into primary visual centres. the gross morphology of the nerve was also examined. ipsilaterally projecting ganglion cells were restricted to the temporal retina, whereas those that project contralaterally were located in all retinal regions. the morph ...19921484118
distinctive pattern of organisation in the retinofugal pathway of a marsupial: ii. optic chiasm.in the mammalian optic chiasm retinal axons from each eye divide into two populations, those that decussate and those that remain uncrossed. in eutherian (placental) mammals, the separation of these pathways is not reflected in the structure of the chiasm. the two populations from each eye are mixed through each hemichiasm, segregating only at the midline, where the uncrossed projection turns back. in this study the optic chiasm of a marsupial, the wallaby, setonix brachyurus (quokka) has been i ...19921484119
role of transferrin in iron uptake by the brain: a comparative study.the role of specific transferrin (tf) and tf receptor interaction on brain capillary endothelial cells in iron transport from the plasma to the brain was investigated by using tf from several species of animals labeled with 59fe and 125i, and 15-day and adult rats. the rate of iron transfer was much greater in the 15-day rats. it was greatest with tf from the mammals, rat, rabbit and human, but much lower with chicken ovotransferrin and quokka (a marsupial), toad, lizard, crocodile, and fish tf. ...19911744249
generation and death of cells in the dorsal lateral geniculate nucleus and superior colliculus of the wallaby, setonix brachyurus (quokka).to study postnatal cell generation in primary visual centres of the quokka, tritiated thymidine was injected into pouch-young aged postnatal day (p)1-p85. brains were examined at p100, just before eye-opening, when primary visual projections are essentially mature. neurons in the dorsal lateral geniculate nucleus (dlgn) and superior colliculus (sc) were generated at p1-p10 and p1-p18 respectively. peak numbers of labelled cells were seen at p3 and p5 in the dlgn and sc. cell death was assessed i ...19911770170
metabolic effects of cortisol, acth, adrenalin and insulin in the marsupial sugar glider, petaurus breviceps.the effects of cortisol, acth, adrenalin and insulin on indices of carbohydrate, fat and protein metabolism were investigated in the conscious marsupial sugar glider petaurus breviceps. short-term i.v. infusion of cortisol at dose rates of 0.02, 0.2 and 1.0 mg/kg per h caused the plasma glucose concentration to rise sharply from the normal range of 3.3-4.4 to 8.1-8.7 mmol/l at the end of the infusion period without significant alteration in plasma free fatty acid (ffa), amino acid or urea concen ...19902174452
effect of available surface water on levels of antidiuretic hormone (lysine vasopressin) and water and electrolyte metabolism of the rottnest island quokka (setonix brachyurus).a sensitive radioimmunoassay was developed to measure circulating levels of the neurohypophysial peptide lysine vasopressin (lvp) in the marsupial quokka (setonix brachyurus), which is abundant on rottnest island off the coast of western australia. animals from locations on the island where free water is completely absent were compared in midsummer with animals from sites where brackish water is available and utilized by the quokkas. in the animals from west end, where free water is absent, circ ...19902295426
early development of retinal ganglion cell dendrites in the marsupial setonix brachyurus, quokka.the dendritic morphology of retinal ganglion cells was studied in flat-mounted retinae of the marsupial setonix brachyurus, quokka. in the adults, horseradish peroxidase (hrp) was applied to the vitread surface of flattened retinae. wide-, large-, medium-, and small-field classes appeared to correspond to gamma, alpha, delta, and beta cells, respectively, in the cat (boycott and wässle, j. physiol. 249:397-419, 1974). to reveal the early stages of dendritic development, hrp was placed on the opt ...19902324323
generation of retinal cells in the wallaby, setonix brachyurus (quokka).we have examined the generation of retinal cells in the wallaby, setonix brachyurus (quokka). animals received a single injection of tritiated thymidine between postnatal days 1-85 and retinae were examined at postnatal day 100. retinae were sectioned, processed for autoradiography and stained with cresyl violet. ganglion cells were labelled by injection of horseradish peroxidase into the optic tracts and primary visual centres. other cells were classified according to their morphology and locat ...19892761691
expanded retinofugal projections to the dorsal lateral geniculate nucleus and superior colliculus after unilateral enucleation in the wallaby setonix brachyurus, quokka.we removed one eye of quokkas either neonatally, before retinal innervation of visual centres, or at 35-40 days postnatal, when projections overlap bilaterally and are more widespread than in the adult. retinal projections to the dorsal lateral geniculate nucleus and superior colliculus at postnatal day 100 were demonstrated following anterograde transport of horseradish peroxidase. there were significant reductions in the size of the dorsal lateral geniculate nucleus and superior colliculus ips ...19892776298
retinal ganglion cell number is unchanged in the remaining eye following early unilateral eye removal in the wallaby setonix brachyurus, quokka.the expanded visual projections which develop after unilateral eye removal have been associated in some studies, but not in others, with the survival of more ganglion cells than normal in the remaining eye. we have addressed this issue using the small wallaby setonix brachyurus, quokka. moreover to determine whether more ganglion cells survive when the eye is removed at a very early stage, we have compared the effect of enucleations at two ages. these were within 3 days of birth, before optic fi ...19892776299
cell death in the inner and outer nuclear layers of the developing retina in the wallaby setonix brachyurus (quokka).we have examined the number and distribution of dying cells in the developing inner (inl) and outer (onl) nuclear layers of sectioned quokka retinae (n = 31) from embryonic day (e)24 to postnatal day (p)192. before birth, dying cells were seen in the optic fissure. thereafter two major phases of cell death took place in the inl. the first phase was more pronounced within the vitread part with peak numbers of dying cells at p50. by contrast, during the second phase, cell death was more extensive ...19892808756
the accessory optic system of the wallaby, setonix brachyurus: anatomy in normal animals and after early unilateral eye removal.we have traced primary visual projections to nuclei of the accessory optic system in the mature wallaby, setonix brachyurus, the "quokka," following unilateral intraocular injections of horseradish peroxidase. the organization of pathways and nuclei is similar to that of other marsupials and to that of eutherian mammals. the dorsal, lateral and medial terminal nuclei receive bilateral input, though nuclei ipsilateral to the injected eye are weakly labelled in comparison with their contralateral ...19882463278
iron-binding properties and amino acid composition of marsupial transferrins: comparison with eutherian mammals and other vertebrates.1. some physicochemical properties of transferrin from three marsupials, viz a possum (trachosurus vulpecula), a kangaroo (macropus fuliginosus) and the quokka (setonix brachyurus) were studied and compared with those of transferrins from mammalian and non-mammalian vertebrate species. 2. the molecular weight of the marsupial transferrins fell within the range of 76,000-79,000 daltons. 3. the marsupial transferrins were similar to the transferrins of eutherian mammals with respect to optical spe ...19882899476
displaced retinal ganglion cells in the wallaby setonix brachyurus.displaced ganglion cells have been examined in wholemounted and sectioned retinae following bilateral injection of horseradish peroxidase into optic tracts of the wallaby, setonix brachyurus, "quokka". such cells, which lie in the vitread part of the inner nuclear layer, are located mainly in superior retina as a streak-like band dorsal to the area centralis and visual streak of orthotopic ganglion cells. only between 1 and 2% of the total ganglion cell population were displaced, but an analysis ...19873424674
patterns of cytogenesis in the developing retina of the wallaby setonix brachyurus.patterns of mitosis were examined during development from embryonic day (e) 19, 9 days before birth, for retinae of the wallaby setonix brachyurus, using cresyl violet stained material. for neural retina, mitosis took place at the ventricular surface from the earliest stage of eye formation until postnatal day (p) 100. numbers of mitotic figures reached a peak of approximately 12,000 by p43. average densities ranged between 300/mm2 and 600/mm2 up to p12 and then fell to below 50/mm2 by p25 befor ...19873434843
cell death in the developing retinal ganglion cell layer of the wallaby setonix brachyurus.the distribution and number of dying cells in the developing retinal ganglion cell layer of the wallaby setonix brachyurus were assessed by using cresyl violet stained tissue. the density of dying cells has been expressed per 100 live cells for the entire retinal surface, data being presented as a grid of 500 micron squares. for statistical analysis, retinae were divided into 8 regions; dorsal, ventral, nasal, and temporal quadrants, each further divided into center and periphery. this method al ...19873680622
in vitro antibody-mediated macrophage activity on breinlia macropi microfilariae. i. adherence and cytotoxicity.intense adherence accompanied by cytotoxicity, which initially occurred at 4 h of interaction was observed when the microfilariae of breinlia macropi were introduced to cultures of quokka peritoneal macrophages previously sensitized in 20% immune serum. no significant difference in the adherence or cytotoxic effects was observed among macrophages from normal, microfilaraemic and amicrofilaraemic quokkas. however, the serum component mediating these effects was found only in microfilaraemic and s ...19863703569
in vitro antibody-mediated macrophage activity on breinlia macropi microfilariae. ii. ultrastructural and video recording investigations of adherence and cytotoxicity.video recordings and ultrastructural studies have revealed an intricate sequence of antibody-mediated cytotoxic activity by quokka peritoneal macrophages on breinlia macropi microfilariae. the microfilaricidal activity was effected by at least two types of macrophages measuring 17 micrometers and 8 micrometers in diameter respectively. the relatively large macrophages were responsible for trapping, encircling and eventually degrading the highly motile microfilariae in a sequence of events in whi ...19863725416
development of visual projections in the marsupial, setonix brachyurus.retinal projections to the primary visual centres were studied following injection of tritiated proline into one eye in the marsupial, setonix brachyurus between 10 and 100 days postnatal and in adults. initially, projections from the two eyes overlapped extensively, particularly between 20 and 50 days. there was a gradual refinement thereafter, including a segregation of inputs from the two eyes within both the lateral geniculate nucleus (lgn) and superior colliculus (sc) by 70 days. such refin ...19863826648
numbers of axons in the optic nerve and of retinal ganglion cells during development in the marsupial setonix brachyurus.numbers of axons during postnatal development in the optic nerve of the marsupial setonix brachyurus were estimated from electron micrographs. between 14 and 45 days axon totals rose 10-fold from 95,000 to 961,000. thereafter, counts decreased gradually by almost 5-fold stabilising at the adult level of 180,000-224,000 between 130-150 days. myelinated axons were first seen at 85 days and constituted 76% of all axons by 150 days, compared to almost 100% in the adult. at comparable stages of devel ...19863948024
iron metabolism during lactation and suckling in a marsupial, the quokka (setonix brachyurus).the iron status and transfer of iron through the milk during lactation were determined in a marsupial, the quokka, setonix brachyurus. lactating animals were not anaemic and had similar liver and spleen non-haem iron values to non-lactating female adult animals but about 40% less non-haem iron than male adults. the milk iron concentration was very high during the period of lactation when the young is confined to the pouch, averaging about 20 micrograms/ml (eight times the plasma iron concentrati ...19862875836
salmonella infections in a marsupial, the quokka (setonix brachyurus), in relation to seasonal changes in condition and environmental stress.an unusual abundance of salmonella infections was studied in an island population of a wild marsupial, the quokka (setonix brachyurus), which experiences starvation in summer associated with significant mortality. the frequency of infections was found to vary seasonally over most parts of the island, with high infection rates (70 to 100%) in summer and low infection rates (0 to 30%) in winter. in some samples, there was an average of as many as two isolations per animal, and up to five isolation ...19854004242
changing distribution of retinal ganglion cells during area centralis and visual streak formation in the marsupial setonix brachyurus.injections of the axonal marker horseradish peroxidase (hrp) were made into optic tracts and/or visual centres of setonix brachyurus, a small wallaby (quokka) during development and in adults. distributions of hrp-labelled and unlabelled cells in the retinal ganglion cell layer were estimated from sections or wholemounts counterstained with cresyl violet. between 20 and 40 days postnatal we did not observe an area centralis or visual streak in either the labelled or unlabelled cell populations. ...19854075108
marsupial neurohypophysial hormones: identification of mesotocin, lysine vasopressin, and phenypressin in the quokka wallaby (setonix brachyurus).the neurohypophysial hormones of the quokka wallaby (setonix brachyurus) have been isolated through preparative high pressure liquid chromatography (hplc). one oxytocin-like and two vasopressin-like peptides have been found. these peptides have been characterized by their amino acid composition and by their retention time in hplc. mesotocin ([i1e8]-oxytocin) has been identified by amino acid composition, polar partition chromatography, high pressure liquid chromatography with a reversed phase co ...19836618161
the evolution of an area centralis and visual streak in the marsupial setonix brachyurus.the distribution, morphology, size, and number of cells in the retinal ganglion layer of the marsupial setonix brachyurus, "quokka," was studied from 25 days postnatal to adulthood using nissl-stained wholemounts. the total cell population was evenly distributed up to 50 days, but by 75 days highest densities were generally observed in a broad band extending across the nasotemporal axis. at 87 days, a temporally situated area centralis was seen for the first time. this was embedded in a horizont ...19836863603
lipomatosis in a quokka (setonix brachyurus) 19827138440
characterization and properties of a progesterone receptor in the uterus of the quokka (setonix brachyurus).a progesterone receptor system, with a high specificity for progestins, was detected in the uterine tissue of the marsupial, setonix brachyurus (quokka), using the synthetic progestin 17 alpha, 21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione (r5020). the apparent equilibrium dissociation constant of the ligand binding to the cytosolic component was 2.2 nmol/l, and to the nuclear component 4.8 nmol/l. significant loss of binding ability of the receptor occurred when cytosol was pretreated with dext ...19827200116
a study of isolation procedures for multiple infections of salmonella and arizona in a wild marsupial, the quokka (setonix brachyurus). 19826763026
a quantitative comparison of the parts of the brains of two australian marsupials and some eutherian mammals.the size and composition of the brains of the quokka wallaby (setonix brachyurus) and the brush-tailed possum (trichosurus vulpecula) were compared with those of the rat, rabbit, cat, sheep, and human. separate structures were taken from the brains by standardized dissection and their weights compared. particular attention was paid to the relationships between the size of the amygdala and other brain structures. marsupials were within the eutherian range in the ratio of whole brain weight to bod ...19817237105
resistance to the nitrogen-mobilizing, diabetogenic action of cortisol in a small wallaby (setonix brachyurus). 19817011896
uterine factors and delayed implantation in macropodid marsupials.local factors controlling uterine functions in macropodids are reviewed and the components of uterine fluids are examined. activation of the diapausing blastocyst and subsequent development of the expanding vesicle are associated with a changing uterine environment. concentrations of proteins, calcium and zinc in uterine exudates alter during gestation; the changes appear to be related both to the stage of development of the conceptus and to the hormonal milieu. in addition the endometrium itsel ...19817014865
quantitative alterations of the aerobic bacterial flora of the pouch of setonix brachyurus (quokka) during oestrus, anoestrus, pregnancy and lactating anoestrus (pouch young). 19817041871
mortalities associated with herpesvirus infection in captive macropods.fatal cases of herpesvirus infection in a quokka (setonix brachyurus), eight grey dorcopsis wallabies (dorcopsis muelleri luctuosa) in two separate outbreaks, as well as presumptive fatal herpesvirus infection in a western grey kangaroo (macropus fuliginosus) are described. all were captive animals and deaths were preceded by a period of stress. lesions occurred most often in alimentary tract epithelium, respiratory tract, skin, genital epithelium, conjunctivae, liver and adrenal cortex. herpesv ...19816264169
difference in concentration of progesterone in plasma between pregnant and non-pregnant quokkas (setonix brachyurus).the plasma progesterone concentrations during pregnancy and the oestrous cycle of the quokka were measured daily after each had been initiated by the removal of pouch young. progesterone levels ranged from 0.6 ng/ml in the early stages of the oestrous cycle to about 2.5 ng/ml at the peak of the luteal phase. there was no significant difference between pregnant and non-pregnant states before the removal of the pouch young nor in the latter half of the cycle. however, the plasma progesterone conce ...19807359075
a histochemical study of denervated marsupial hemidiaphragm.the marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. the type ii muscle fibres hypertrophied up to 20 days postoperation and then regressed. however, the type i fibres hypertrophied throughout the experimental period (100 days) studied. unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. an enhancement of the atpase reaction in the denervated type i fibres may be due to dedifferentiation. presumably ...1979156124
adrenocortical function and a field population of a macropodid marsupial (setonix brachyurus, quoy and gaimard).concentrations of corticosteroids and aldosterone have been measured in the plasma and related to the maximum cortisol binding capacity, to the concentration of sodium and potassium of the plasma and to the condition of the animals, in a natural population of the quokka (setonix brachyurus, quoy & gaimard) on rottnest island, western australia. a marked population in one area has been repetitively sampled at approximately 6 week intervals over a period of 2 years. animals were found to be in sig ...1979225402
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