Julie M Old
Western Sydney University, Science, Faculty Member
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Quolls are carnivorous marsupials in the family Dasyuridae with characteristic white spots. They are distributed throughout Australia and New Guinea, but uncommonly seen due to their mostly nocturnal solitary nature, and large home... more
Quolls are carnivorous marsupials in the family Dasyuridae with characteristic white spots. They are distributed throughout Australia and New Guinea, but uncommonly seen due to their mostly nocturnal solitary nature, and large home ranges. All Australian quolls are listed as ‘near threatened' or ‘endangered' at state, national and international levels, largely due to human-induced threats. Threats include introduced predators, habitat loss through clearing and modifications including changed fire regimes, disease, human persecution, vehicle collisions and accidental or targeted poisoning by humans and cane toads (Rhinella marina). Conservation efforts that have focussed on reducing introduced predators, and minimising the impact of cane toads, have aided some translocations, hence species recovery in some local areas of Australia has occurred. Where species conservation has required captive breeding for translocation, successful captive management has been crucial. We summar...
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There are three species of wombat, two hairy-nosed and the barenosed wombat (Vombatus ursinus). The southern hairy-nosed wombat (Lasiorhinus latifrons) is threatened (Woinarski & Burbidge, 2016) whilst the northern hairy-nosed wombat... more
There are three species of wombat, two hairy-nosed and the barenosed wombat (Vombatus ursinus). The southern hairy-nosed wombat (Lasiorhinus latifrons) is threatened (Woinarski & Burbidge, 2016) whilst the northern hairy-nosed wombat (Lasiorhinus krefftii) is critically endangered (Taggart, Martin, & Horsup, 2016). The bare-nosed wombat is regarded as Least Concern (Taggart, Martin, & Menkhorst, 2016). All wombats are large native herbivorous grazers, with many adaptations to Australia's low-productivity habitats (Evans et al., 2006; Johnson, 1998; Sharp & Trusler, 2015). The most obvious and wellknown adaptation is burrowing. Burrowing allows wombats to increase home range size, without needing to increase energy expenditure
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The pro-inflammatory cytokine, Interleukin-6 (IL-6), has not yet been fully characterised in the model macropod, Macropus eugenii, due to incomplete sequence information in publically available genome databases. Using a Rapid... more
The pro-inflammatory cytokine, Interleukin-6 (IL-6), has not yet been fully characterised in the model macropod, Macropus eugenii, due to incomplete sequence information in publically available genome databases. Using a Rapid Amplification of cDNA Ends strategy we have confirmed the expression and complete nucleotide sequence for this molecule in lymph node tissue and activated leukocytes. Structural conservation of the mature wallaby IL-6 molecule was high when compared with human IL-6, although there was only 34% amino acid sequence identity with the human IL-6 peptide, consistent with reports of the evolutionary divergence of this cytokine. We also report the discovery of MeIL-6Δ2, a splice variant missing exon 2, which directly translates to a truncated non-functional peptide, but which may also code for an alternative peptide that is translated downstream of the canonical IL-6 start site. This putative gene product is predicted to maintain some, if not all, of the functions of macropod IL-6 and is the first IL-6 isoform reported outside of eutherian mammals.
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There is currently limited information regarding the levels of infection and distribution of sarcoptic mange in the wombat population throughout Australia. We analyzed cases of sarcoptic mange in bare-nosed wombats reported into WomSAT, a... more
There is currently limited information regarding the levels of infection and distribution of sarcoptic mange in the wombat population throughout Australia. We analyzed cases of sarcoptic mange in bare-nosed wombats reported into WomSAT, a website and mobile phone application where citizen scientists can upload sightings of wombats, burrows, and sarcoptic mange status. We used Maxent software to predict locations and the environmental factors associated with sarcoptic mange occurrence in bare-nosed wombats. A total of 1379 sarcoptic mange-infected and 3043 non-sarcoptic mange-infected wombats were reported by 674 and 841 citizen scientists, respectively. Of all the wombats reported to WomSAT from 2015 to 2019, 31.2% were infected with sarcoptic mange. Sarcoptic mange in bare-nosed wombats was reported in 502 suburbs across four states. New South Wales had the highest number of sarcoptic mange cases reported to WomSAT. There was no statistically significant seasonal variation of sarcoptic mange levels in bare-nosed wombats. The model showed that Euclidean distance to urban areas was the highest contributing factor for sarcoptic mange occurrence. As distance to urban areas decreased, the suitability for sarcoptic mange increased. Annual precipitation was the next contributing factor in the model, with higher rainfall of 400-700 mm correlating to an increase in sarcoptic mange occurrence. As the data collected to date have provided the largest-scale contemporary distribution of sarcoptic mange in wombats, data should continue to be collected by citizen scientists as it is an easy and low-cost method of collecting data over large areas. We suggest targeting the identified hotspot areas and more site-specific studies for studying and mitigating sarcoptic mange in bare-nosed wombats.
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This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.
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Roads directly impact wildlife through vehicle collisions. In Australia only a few studies have examined the impact of environmental characteristics on wombat roadkill. We analysed wombat roadkills reported into WomSAT, a website and... more
Roads directly impact wildlife through vehicle collisions. In Australia only a few studies have examined the impact of environmental characteristics on wombat roadkill. We analysed wombat roadkills reported into WomSAT, a website and application where citizen scientists can upload sightings of wombats, to map wombat roadkill across their distribution. We used Maxent software to identify the main factors influencing wombat roadkill hotspots. A total of 2391 wombat deaths on roads were reported by 567 citizen scientists from 2015 to 2019. More wombat roadkill deaths occurred in winter, with most unaffected by sarcoptic mange. The average daily solar exposure, distance to populated areas, precipitation of warmest quarter (bio 18), temperature seasonality (bio 4), and precipitation seasonality (bio 15) were identified as the main factors influencing wombat roadkill. The most roadkills reported per kilometre (3.7/km) occurred on Old Bega Road and Steeple Flat Road, in the New South Wales...
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Wombats suffer from sarcoptic mange, a mite infection that ultimately leads to their death from secondary infections. In 2017, wildlife carers were granted legal approval to treat bare-nosed wombats (Vombatus ursinus) for sarcoptic mange... more
Wombats suffer from sarcoptic mange, a mite infection that ultimately leads to their death from secondary infections. In 2017, wildlife carers were granted legal approval to treat bare-nosed wombats (Vombatus ursinus) for sarcoptic mange in the field using 4 mL of topical Cydectin® per adult wombat. However, (limited) scientific field trials suggest approved protocols are inadequate which has been supported anecdotally by wildlife carers. Elucidating carer experience is key to holistically advancing understandings of sarcoptic mange treatment. We interviewed 18 wildlife carers regarding the use of Cydectin® to treat free-ranging adult wombats infected with sarcoptic mange which uncovered 43 detailed case studies for examination. Case studies revealed that wildlife carers have used 10-200-mL doses of topical Cydectin® to treat wombats to recovery. These results suggest there is no best-fit for treating wombats in the field, due to individual differences in observed levels of sarcoptic mange severity and differences in wombat behavior. Furthermore, wildlife carers suggested pour-on Cydectin® appeared non-toxic to wombats at rates as high as 200 mL per treatment. We recommend scientific trials should be undertaken to determine the impact and efficacy of the varying treatment regimens, including low and high doses of topical Cydectin® on bare-nosed wombats. This information is required for regulating authorities, and subsequently wildlife carers, and managers, to make fully informed decisions about wombat sarcoptic mange treatment.
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Background Roads have major ecological impacts on wildlife. Vehicle collisions most frequently impact large herbivores due to their larger home range compared to smaller animals, and higher population density compared to carnivores.... more
Background Roads have major ecological impacts on wildlife. Vehicle collisions most frequently impact large herbivores due to their larger home range compared to smaller animals, and higher population density compared to carnivores. Kangaroos (Macropus spp.) account for a large proportion of reported wildlife vehicle collisions that occur in N S W, Australia. We aimed to evaluate what influenced road mortality of eastern grey kangaroos (Macropus giganteus) in a temperate rural/suburban region. The location of roadkilled kangaroos found on or near two 1 km stretches of road in Richmond NSW was recorded throughout 2014 and 2015. Weather and moon phase data were recorded for the date of each roadkilled kangaroo. Transects were setup on both roads, and multiple road and landscape features, including the width of roadside, fence construction, habitat type, and distance from street lights measured at 50 m intervals. Data were analyzed to explore which landscape features and temporal facto...
Research Interests: Geography, Ecology, Marsupials, Habitat, Wildlife, and 4 moreRural Areas, Roads, Eastern Grey Kangaroo, and Roadkill
Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail... more
Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail possums is crucial to understanding the factors limiting their survival, and was the focus of this study. Spotlighting surveys were conducted to locate ringtail possums, and scat and vegetation samples were collected for microhistological analysis. Ringtail possums were most frequently observed in red stringybark followed by bundy box and black cypress pine trees, and this correlated with the most common dietary items consumed.
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Hearing is essential for communication, to locate prey and to avoid predators. We addressed the paucity of information regarding hearing in Australian native mammals by specifically assessing the hearing range and sensitivity of the... more
Hearing is essential for communication, to locate prey and to avoid predators. We addressed the paucity of information regarding hearing in Australian native mammals by specifically assessing the hearing range and sensitivity of the red-tailed phascogale (Phascogale calura), the kultarr (Antechinomys laniger) and the spinifex hopping-mouse (Notomys alexis). Auditory brainstem response (ABR) audiograms were used to estimate hearing thresholds within the range of 1–84 kHz, over a dynamic range of 0–80 dB sound pressure level (SPL). Phascogales had a hearing range of 1–40 kHz, kultarrs 1–35 kHz and hopping-mice 1–35 kHz, with a dynamic range of 17–59 dB SPL, 20–80 dB SPL and 30–73 dB SPL, respectively. Hearing for all species was most sensitive at 8 kHz. Age showed no influence on optimal hearing, but younger animals had more diverse optimal hearing frequencies. There was a relationship between males and their optimal hearing frequency, and greater interaural distances of individual ma...
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People's behaviour towards the conservation of Australian wildlife is important, because people's actions are the main causative factor associated with the demise and future recovery of wildlife conservation. We investigated the... more
People's behaviour towards the conservation of Australian wildlife is important, because people's actions are the main causative factor associated with the demise and future recovery of wildlife conservation. We investigated the type and prevalence of behaviour performed by NSW residents towards wildlife conservation, investigate participants’ willingness to perform conservation behaviours in the future, and identify the barriers preventing people from engaging in conservation action. New South Wales (NSW) residents (n=312) participated in an online questionnaire in a cross-sectional study. Overall, participants’ intention to engage, and rates of actual participation, in conservation behaviours was low. The latter was mostly due to lack of time, money, knowledge, and the impact of health and fitness levels. The knowledge gained from this study can be harnessed to inform future policy and management decisions, design interventions to change conservation behaviours, and provid...
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B-cells are key to humoral immunity, are found in multiple lymphoid organs, and have the unique ability to mediate the production of antigen-specific antibodies in the presence of pathogens. The marsupial immunoglobulin (Ig) heavy (H)... more
B-cells are key to humoral immunity, are found in multiple lymphoid organs, and have the unique ability to mediate the production of antigen-specific antibodies in the presence of pathogens. The marsupial immunoglobulin (Ig) heavy (H) chain locus encodes four constant region isotypes, IgA, IgG, IgM and IgE, but no IgD, and there are two light (L) chain isotypes, lambda (Igλ) and kappa (Igκ). To gain an understanding of the marsupial humoral immune system, B-cell transcriptomes generated by single-cell RNA sequencing from gray short-tailed opossum (Monodelphis domestica) splenocytes, and peripheral blood mononuclear cells were analysed. The cells used were from a single unimmunized animal and the majority of B-cells were transcribing IgM heavy chains. The ratio of Ig light chain use was roughly 2:1, Igλ:Igκ in this individual. This was not predicted due to Igκ being the more complex of the two L chain loci. The variable (V) gene segment pairs used in individual B-cells confirm greater diversity provided by the L chain V. This study is the first to report on using single cell analysis to investigate Ig repertoires in a marsupial and confirms a number of prior hypothesis, as well as revealing some surprises.
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Roads directly impact wildlife through vehicle collisions. In Australia only a few studies have examined the impact of environmental characteristics on wombat roadkill. We analysed wombat roadkills reported into WomSAT, a website and... more
Roads directly impact wildlife through vehicle collisions. In Australia only a few studies have examined the impact of environmental characteristics on wombat roadkill. We analysed wombat roadkills reported into WomSAT, a website and application where citizen scientists can upload sightings of wombats, to map wombat roadkill across their distribution. We used Maxent software to identify the main factors influencing wombat roadkill hotspots. A total of 2391 wombat deaths on roads were reported by 567 citizen scientists from 2015 to 2019. More wombat roadkill deaths occurred in winter, with most unaffected by sarcoptic mange. The average daily solar exposure, distance to populated areas, precipitation of warmest quarter (bio 18), temperature seasonality (bio 4), and precipitation seasonality (bio 15) were identified as the main factors influencing wombat roadkill. The most roadkills reported per kilometre (3.7/km) occurred on Old Bega Road and Steeple Flat Road, in the New South Wales southern tablelands. Reduced reporting corresponded with a reduced number of citizen scientists continuing to report sightings over time, reflecting the limitations of the data collected by citizen scientists. However, data should continue to be collected by citizen scientists as it is an easy and low-cost method of collecting data over large areas, and can provide information to managers to support conservation efforts directed at reducing roadkill. Our study emphasises the need to continue to engage and reward citizen scientists for their efforts.
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There are many limitations when using traditional laboratory species. Limits on variation, may result in limited outcomes, at both the species and individual level, due to different individuals/species having diverse physiological... more
There are many limitations when using traditional laboratory species. Limits on variation, may result in limited outcomes, at both the species and individual level, due to different individuals/species having diverse physiological processes, or differing molecular and genetic mechanisms. By using a variety of model species, we will be able to develop creative solutions to biological problems and identify differences of which we were not previously aware. The laboratory mouse has been a suitable model species for various mammalian studies, however most are bred specifically for laboratory research with limited variability due to selective breeding. Marsupial models offer unique research opportunities compared to eutherian models. We believe that there should be an expansion in marsupial model species, and the introduction of the red-tailed phascogale (Phascogale calura), a dasyurid marsupial, should be one of them. Phascogales are easily managed in captivity, and there are now multiple studies involving their development, reproduction, nutrition, behavior and immune system, which can serve as a baseline for future studies. The addition of the phascogale as a model species will improve future mammalian studies by introducing variability and offer alternate solutions to biological problems, particularly in the areas of genetics, nutrition, immunology, the neuro-endocrine system, and ageing, due to their semelparous reproductive strategy and hence, subsequent predictive physiology. In this review, we provide information based on existing research on red-tailed phascogales to support their inclusion as a model species.
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Mosquito-borne viruses are well recognized as a global public health burden amongst humans, but the effects on non-human vertebrates is rarely reported. Australia, houses a number of endemic mosquito-borne viruses, such as Ross River... more
Mosquito-borne viruses are well recognized as a global public health burden amongst humans, but the effects on non-human vertebrates is rarely reported. Australia, houses a number of endemic mosquito-borne viruses, such as Ross River virus, Barmah Forest virus, and Murray Valley encephalitis virus. In this review, we synthesize the current state of mosquito-borne viruses impacting non-human vertebrates in Australia, including diseases that could be introduced due to local mosquito distribution. Given the unique island biogeography of Australia and the endemism of vertebrate species (including macropods and monotremes), Australia is highly susceptible to foreign mosquito species becoming established, and mosquito-borne viruses becoming endemic alongside novel reservoirs. For each virus, we summarize the known geographic distribution, mosquito vectors, vertebrate hosts, clinical signs and treatments, and highlight the importance of including non-human vertebrates in the assessment of ...
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Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the... more
Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the presence or impact of tick-borne pathogens in native Australian wildlife. Wombats are particularly susceptible to the effects of the ectoparasite Sarcoptes scabiei which causes sarcoptic mange, the reason for which is unknown. Factors such as other ectoparasites and their associated pathogens may play a role. A critical understanding of the species of ectoparasites that parasitise wombats and their pathogens, and particularly ticks, is therefore warranted. This review describes the ectoparasites of wombats, pathogens known to be associated with those ectoparasites, and related literature gaps. Pathogens have been isolated in most tick species that typically feed on wombats; however, there are minimal molecular studies to determine the presence of pathogens in any other wombat ectoparasites. The development of next-generation sequencing (NGS) technologies allows us to explore entire microbial communities in ectoparasite samples, allowing fast and accurate identification of potential pathogens in many samples at once. These new techniques have highlighted the diversity and uniqueness of native ticks and their microbiomes, including pathogens of potential medical and veterinary importance. An increased understanding of all ectoparasites that parasitise wombats, and their associated pathogens, requires further investigation.
Research Interests: Microbiology, Parasitology, Medical Microbiology, Infectious Diseases, Host-parasite Coevolution, and 11 moreMedicine, Emerging Infectious Diseases, Ticks, Marsupial, Parasites, Wombats, Ectoparasites, Host Parasite Interaction, Ticks and Tick Borne Diseases, Veterinary Sciences, and Animal Parasites
Quolls are carnivorous marsupials in the family Dasyuridae with characteristic white spots. They are distributed throughout Australia and New Guinea, but uncommonly seen due to their mostly nocturnal solitary nature, and large home... more
Quolls are carnivorous marsupials in the family Dasyuridae with characteristic white spots. They are distributed throughout Australia and New Guinea, but uncommonly seen due to their mostly nocturnal solitary nature, and large home ranges. All Australian quolls are listed as ‘near threatened’ or ‘endangered’ at state, national and international levels, largely due to human-induced threats. Threats include introduced predators, habitat loss through clearing and modifications including changed fire regimes, disease, human persecution, vehicle collisions and accidental or targeted poisoning by humans and cane toads (Rhinella marina). Conservation efforts that have focussed on reducing introduced predators, and minimising the impact of cane toads, have aided some translocations, hence species recovery in some local areas of Australia has occurred. Where species conservation has required captive breeding for translocation, successful captive management has been crucial. We summarise rese...
Research Interests: Zoology, Biology, Ecology, Marsupials, Dasyurids, and 5 moreQuoll, Marsupialia, Dasyuridae, Tiger Quoll, and Spotted Tail Quoll
Abstract Roadkill is a worldwide issue that can cause local population extinctions. In Australia numerous species are affected, however the bare-nosed wombat (Vombatus ursinus) is particularly vulnerable due to its preference for... more
Abstract Roadkill is a worldwide issue that can cause local population extinctions. In Australia numerous species are affected, however the bare-nosed wombat (Vombatus ursinus) is particularly vulnerable due to its preference for disturbed habitats. Collisions with motor vehicles causes significant damage to the vehicle and sometimes the driver, as well as wounding or killing the wombat. Virtual fences are light and sound-based devices, originally developed in Austria that can be used to reduce roadkill through mitigation. They have had mixed results. In this study a virtual fence was installed along a 1.5 km stretch of road in semi-rural NSW, Australia, with the aim of reducing wombat roadkill through the use of this form of mitigation strategy. The number of roadkilled wombats was counted before and after the fence was installed in March 2020. Prior to the fence being installed 23 wombats were killed and after the fence was installed six wombats were killed. Along Old Bega Road, outside of the fenced area 64 wombats were killed pre-fence installation and 17 post fence installation. Bare-nosed wombats are semi-fossorial ecosystem engineers with an important role in the ecosystem and despite being listed as Least Concern are readily impacted by roadkill. Virtual fencing implemented in regions that have high wombat roadkill rates may aid in reducing road deaths and species conservation. However, we recommend that more research is required to assess virtual fencing, as a roadkill mitigation strategy, including an investigation into a larger number of species in a range of different habitats.
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Moxidectin (MOX) is a macrocyclic lactone approved worldwide for the treatment of both endo- and ecto-parasites in many mammalian species. The aim of this study was to assess the efficacy of MOX as a treatment against parasites in a range... more
Moxidectin (MOX) is a macrocyclic lactone approved worldwide for the treatment of both endo- and ecto-parasites in many mammalian species. The aim of this study was to assess the efficacy of MOX as a treatment against parasites in a range of mammalian species. An electronic literature search was performed for publications to the 1st September 2020. A total of 205 papers were retrieved and screened against all required criteria; hence, 35 were papers were reviewed in this study. The level of evidence and methodological quality was analysed, where a total of 13 publications were categorised as a 'randomised control trial', seven were categorised as a 'non-randomised control trial' and 15 as an 'experimental control trial'. The overall methodological quality of the publications was considered low, low to moderate, moderate, moderate to high and high in ten, four, twelve, five and a further four, respectively. We assessed the treatment and possible toxicity of MOX in 13 mammalian species, six investigations reported adverse effects to MOX in a small percentage of individuals. The authors reported observed reactions that were typically mild symptoms that did not require additional therapies, and/or resolved themselves. Further studies are needed to assess the efficacy of MOX treatment in a larger number of species, particularly in wildlife.
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Studies of gene diversity are used to investigate population dynamics, including immunological fitness. Aside from the selection of an appropriate gene target, an important factor that underpins these studies is the ability to recover... more
Studies of gene diversity are used to investigate population dynamics, including immunological fitness. Aside from the selection of an appropriate gene target, an important factor that underpins these studies is the ability to recover viable DNA samples from native animals that are protected, threatened or difficult to sample or locate such as the bare-nosed wombat (Vombatus ursinus). In this study, we used genomic DNA extracted from muscle tissue samples and also identified the optimal method to extract DNA from fresh wombat scat samples to enable further analyses to be performed using non-invasive techniques. The DNA was probed via the polymerase chain reaction using previously targeted marsupial Major Histocompatibility Complex (MHC) gene primers. These genes are highly variable and associated with binding and presentation of pathogens in the immune system. Twenty-three unique MHC Class II DAB V. ursinus gene sequences were translated to 21 unique predicted peptide sequences from...
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Sarcoptic mange is caused by the mite Sarcoptes scabiei and has recently been recognized as an emerging infectious disease of wildlife worldwide. The mite is one of the main causes of population decline in southern hairy-nosed... more
Sarcoptic mange is caused by the mite Sarcoptes scabiei and has recently been recognized as an emerging infectious disease of wildlife worldwide. The mite is one of the main causes of population decline in southern hairy-nosed (Lasiorhinus latifrons) and bare-nosed wombats (Vombatus ursinus). This review focuses on Sarcoptes scabiei infestations in wombats and provides insights into why the disease may be so prevalent in wombats. Current treatment practices and trials conducted in the field to reduce the incidence of sarcoptic mange in wombats are described and critically reviewed. Current and potential future avenues of research are discussed.
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Camera traps are frequently used in wildlife research and may be a useful tool for monitoring behavioural patterns. The suitability of camera traps to monitor behaviour depends on the size, locomotion, and behaviour of the species being... more
Camera traps are frequently used in wildlife research and may be a useful tool for monitoring behavioural patterns. The suitability of camera traps to monitor behaviour depends on the size, locomotion, and behaviour of the species being investigated. The suitability of cameras for documenting the behaviour of eastern grey kangaroos was assessed here by comparing activity patterns collected using cameras to published activity patterns for the species. The activity patterns calculated from camera trap data were largely consistent with data from previous studies, although nocturnal activity appeared to be under-represented. Observations of unusual fighting behaviour illustrates the potential for camera traps to enable capture of novel observations. Kangaroo behaviour appeared to be influenced by the presence of cameras; however, no kangaroos retreated from cameras. Data suggested that kangaroos became habituated to cameras after eight months. The findings of this study suggest that cam...
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Expressed coding sequences for interleukin-6 (IL-6) and interleukin-6 receptor α (IL-6R) were examined in five marsupial species. Full length expressed coding sequences for IL-6 and IL-6R were identified and characterized in the gray... more
Expressed coding sequences for interleukin-6 (IL-6) and interleukin-6 receptor α (IL-6R) were examined in five marsupial species. Full length expressed coding sequences for IL-6 and IL-6R were identified and characterized in the gray short-tailed opossum (Monodelphis domestica). For IL-6, ∼225 bp fragments of the mRNA sequence were identified in the red-tailed phascogale (Phascogale calura), kultarr (Antechinomys laniger), and stripe-faced dunnart (Sminthopsis macroura), while ∼563 bp fragments of mRNA encoding IL-6R were identified in the red-tailed phascogale, kultarr, stripe-face dunnart and fat-tailed dunnart (Sminthopsis crassicaudata). Relative expression levels of IL-6 and IL-6R were examined in the heart, muscle, lung, liver, spleen and kidney of adult red-tailed phascogales, and IL-6 gene expression was found to be significantly higher in the lung and spleen than the other tissues examined, while the expression of IL-6R was significantly higher in the liver, lung and spleen...
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Diversity in major histocompatibility complex (MHC) genes can be correlated with the level of immunological fitness of an individual or group of individuals. This study tested published primer sets designed to amplify fragments of the MHC... more
Diversity in major histocompatibility complex (MHC) genes can be correlated with the level of immunological fitness of an individual or group of individuals. This study tested published primer sets designed to amplify fragments of the MHC Class II DAB and DBB genes to amplify the equivalent gene fragments in red-tailed phascogales (Phascogale calura). Seventeen genomic DNA samples extracted from phascogale muscle tissue were used to amplify the initial DAB and DBB fragments; however, only DAB PCR proved successful. The fragments were 172 bp in length between the primers and had a high level of identity to other known marsupial MHC Class II DAB gene sequences (89–98%), including those of the koala (Phascolarctos cinereus), Tasmanian devil (Sarcophilus harrisii), common brushtail possum (Trichosurus vulpecula) and several wallaby species. Multiple sequence alignment revealed limited variability of MHC Class II genes between the individuals, but eight individual sequences in total. Gen...
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Integrating comparative immunology can improve human, animal, and ecosystem health
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A recent publication in Parasitology Research by (Old et al. Parasitol Res 120:1077-1090, 2021) raises the topical and often controversial issue of the treatment of wildlife by personnel with little or no formal scientific training (e.g.... more
A recent publication in Parasitology Research by (Old et al. Parasitol Res 120:1077-1090, 2021) raises the topical and often controversial issue of the treatment of wildlife by personnel with little or no formal scientific training (e.g. wildlife carers). In a valuable contribution to the subject, Old and colleagues document a wide range of topical (pour-on) application doses and frequencies of moxidectin (Cydectin®) administered in situ to bare-nosed wombats (Vombatus ursinus) by members of the wildlife carer/treater community in southeast Australia to treat sarcoptic mange disease. This treatment occurred under minor use permits issued by the Australian Pesticides and Veterinary Management Authority (APVMA). These permits do not require veterinary supervision, although carers are registered and are expected to comply with the guidelines of this permit. The prevalence and severity of sarcoptic mange in wildlife is influenced by a variety of factors including mite biology, environmental conditions, population density, animal behaviour and immune susceptibility (Browne et al. Bioscience, 2021). In bare-nosed wombats, combinations of these elements play a substantial role in making the treatment of an already difficult disease more complex. (Moroni et al. Parasit Vectors 13:471, 2020) comment that any pharmacological treatment of freeranging wildlife must consider these factors when assessing their feasibility and implications, especially in the context of emerging drug resistance and potential long-term ecological impacts. As individuals with significant interest in sarcoptic mange and representing a range of professional research and veterinary expertise, we see value in providing expert commentary on this issue.
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Roadkill is a worldwide issue that can cause local population extinctions. In Australia numerous species are affected, however the bare-nosed wombat (Vombatus ursinus) is particularly vulnerable due to its preference for disturbed... more
Roadkill is a worldwide issue that can cause local population extinctions. In Australia numerous species are affected, however the bare-nosed wombat (Vombatus ursinus) is particularly vulnerable due to its preference for disturbed habitats. Collisions with motor vehicles causes significant damage to the vehicle and sometimes the driver, as well as wounding or killing the wombat. Virtual fences are light and sound-based devices, originally developed in Austria that can be used to reduce roadkill through mitigation. They have had mixed results. In this study a virtual fence was installed along a 1.5 km stretch of road in semi-rural NSW, Australia, with the aim of reducing wombat roadkill through the use of this form of mitigation strategy. The number of roadkilled wombats was counted before and after the fence was installed in March 2020. Prior to the fence being installed 23 wombats were killed and after the fence was installed six wombats were killed. Along Old Bega Road, outside of the fenced area 64 wombats were killed pre-fence installation and 17 post fence installation. Bare-nosed wombats are semi-fossorial ecosystem engineers with an important role in the ecosystem and despite being listed as Least Concern are readily impacted by roadkill. Virtual fencing implemented in regions that have high wombat roadkill rates may aid in reducing road deaths and species conservation. However, we recommend that more research is required to assess virtual fencing, as a roadkill mitigation strategy, including an investigation into a larger number of species in a range of different habitats.
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Single-cell transcriptome analysis of the B-cell repertoire reveals the usage of immunoglobulins in the gray short-tailed opossum (Monodelphis domestica)
Moxidectin (MOX) is a macrocyclic lactone approved worldwide for the treatment of both endo-and ecto-parasites in many mammalian species. The aim of this study was to assess the efficacy of MOX as a treatment against parasites in a range... more
Moxidectin (MOX) is a macrocyclic lactone approved worldwide for the treatment of both endo-and ecto-parasites in many mammalian species. The aim of this study was to assess the efficacy of MOX as a treatment against parasites in a range of mammalian species. An electronic literature search was performed for publications to the 1 st September 2020. A total of 205 papers were retrieved and screened against all required criteria; hence, 35 were papers were reviewed in this study. The level of evidence and methodological quality was analysed, where a total of 13 publications were categorised as a 'randomised control trial', seven were categorised as a 'non-randomised control trial' and 15 as an 'experimental control trial'. The overall method-ological quality of the publications was considered low, low to moderate, moderate, moderate to high and high in ten, four, twelve, five and a further four, respectively. We assessed the treatment and possible toxicity of MOX in 13 mammalian species, six investigations reported adverse effects to MOX in a small percentage of individuals. The authors reported observed reactions that were typically mild symptoms that did not require additional therapies, and/or resolved themselves. Further studies are needed to assess the efficacy of MOX treatment in a larger number of species, particularly in wildlife.
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All mammals are characterized by the ability of females to produce milk. Marsupial (metatherian) and monotreme (prototherian) young are born in a highly altricial state and rely on their mother’s milk for the first part of their life.... more
All mammals are characterized by the ability of females to produce milk. Marsupial (metatherian) and monotreme (prototherian) young are born in a highly altricial state and rely on their mother’s milk for the first part of their life. Here we review the role and importance of milk in marsupial and monotreme development. Milk is the primary source of sustenance for young marsupials and monotremes and its composition varies at different stages of development. We applied nutritional geometry techniques to a limited number of species with values available to analyze changes in macronutrient composition of milk at different stages. Macronutrient energy composition of marsupial milk varies between species and changes concentration during the course of lactation. As well as nourishment, marsupial and monotreme milk supplies growth and immune factors. Neonates are unable to mount a specific immune response shortly after birth and therefore rely on immunoglobulins, immunological cells and ot...
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Much of the literature on wombat diet is concerned only with the broad categories of consumed matter, and there is little about their specific nutritional requirements despite diet playing a major role in health. This study gathered... more
Much of the literature on wombat diet is concerned only with the broad categories of consumed matter, and there is little about their specific nutritional requirements despite diet playing a major role in health. This study gathered information by surveying zoological parks and wildlife carers about current feeding regime, diet and the prevalence of nutritional or dental disorders of wombats held in captivity, with the aim of improving the diets of captive wombats, thus their health and welfare outcomes. Data on the composition, variation and basis of diets for 31 bare-nosed or common wombats (Vombatus ursinus) and 19 southern hairy-nosed wombats (Lasiorhinus latifrons) were gathered from 13 facilities. The nutritional values of diets fed to wombats in captivity were calculated and compared with known dietary requirements for bare-nosed wombats. Results demonstrate that the current diet of wombats held in captivity often consists of a high portion of fruits, vegetables and livestock...
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Sarcoptic mange is a threat to bare-nosed wombats (Vombatus ursinus) in Australia and a major factor contributing to the decline in populations of this species. It is caused by a mite, Sarcoptes scabiei, and if untreated can lead to... more
Sarcoptic mange is a threat to bare-nosed wombats (Vombatus ursinus) in Australia and a major factor contributing to the decline in populations of this species. It is caused by a mite, Sarcoptes scabiei, and if untreated can lead to severe irritation, blindness, starvation and eventual death. Modes of transmission likely occur through direct contact between wombats and indirectly from wombat burrows. Our study aimed to estimate and compare the numbers of bare-nosed wombats at three study sites, and to determine how rainfall, temperature and humidity influenced the incidence of sarcoptic mange in the populations. The abundances of macropods and rabbits were also compared with wombat abundance and sarcoptic mange prevalence at the three study sites. Across the study sites, 1655 bare-nosed wombats were observed. Sarcoptic mange prevalence was between 7.0% and 40.7%, depending on site, season and year. Sarcoptic mange prevalence correlated with yearly rainfall, with a higher incidence o...
Research Interests: Parasitology, Zoology, Infectious disease epidemiology, Ecology, Mammalogy, and 14 moreMarsupials, Parasite Ecology, Wildlife Diseases, Mammals, Veterinary Parasitology, Parasites, Host-parasite interactions, Wombats, Vombatiformes, Mites, Animal Parasites, Sarcoptic Mange, Public Health Significance of Zoonotic Parasites, and Vombatidae
In this review we investigated the diet and nutrition of wombats and highlight areas for future research. The low energy requirements of wombats, conservative foraging behaviours and burrowing lifestyle allow them to subsist on... more
In this review we investigated the diet and nutrition of wombats and highlight areas for future research. The low energy requirements of wombats, conservative foraging behaviours and burrowing lifestyle allow them to subsist on low-quality food. Furthermore, their digestive anatomy and physiology is well adapted for digesting the resources available in their habitats. All species feed predominantly on native grasses; however, the nutritional requirements of juvenile and aged wombats are largely unknown. Changes to food availability and grass species in wombat habitats may alter their diet and nutritional intake. Also, despite evidence suggesting that wombats can satisfy their water requirements via the food they eat, the minimum threshold of water content at which wombats will cease feeding is unknown. Other areas for future research include investigating factors that affect digesta retention times (such as age or lactation), and the development of a method to determine age, because...
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The authors have withdrawn this preprint due to erroneous posting.
People's attitudes towards the conservation of Australian wildlife is of particular importance as the types of attitudes people hold can have a significant impact on conservation solutions. We investigated attitudes held towards... more
People's attitudes towards the conservation of Australian wildlife is of particular importance as the types of attitudes people hold can have a significant impact on conservation solutions. We investigated attitudes held towards Australian wildlife and conservation solutions. A sample of 312 residents participated in an online questionnaire. An ‘ecoscientistic’ attitude was the most commonly held attitude, highlighting that wildlife are appreciated for the role they play within our ecosystem. There was a significant association between age and attitude towards Koala Phascolarctos cinereus and Crownof-thorns starfish Acanthaster planci conservation and a significant association between socio-economic status and attitude towards Brush-turkey Alectura lathami conservation. Most participants agreed that action should be taken towards wildlife conservation in the future. Conservation managers and other key stakeholders need to capitalise on this information to increase public support...
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Ectoparasites are a leading cause of arthropod-borne disease in animals, and humans. Defined as arthropods which spend an entire portion of their life cycle on the host, ectoparasites include the ticks and mites (Acarina), and the lice... more
Ectoparasites are a leading cause of arthropod-borne disease in animals, and humans. Defined as arthropods which spend an entire portion of their life cycle on the host, ectoparasites include the ticks and mites (Acarina), and the lice and fleas of the insect family. Their role in human disease transmission has been well documented, as has their importance in agricultural and domestic animals. Little however has been done to comprehensively examine the role these organisms may play in disease transmission and their impact upon native Australian fauna. It is important to consider the effects of such disease agents on the survival of both captive and wild native animal populations, particularly as exposure to a novel pathogen may remove endangered animals that are a vital pool of genetic diversity.
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Wombats are large marsupial grazers native to Australia. They are ‘ecosystem engineers’ due to their burrowing, impacting rates of soil turnover, assisting with nutrient cycling and water infiltration, and creating habitat for other... more
Wombats are large marsupial grazers native to Australia. They are ‘ecosystem engineers’ due to their burrowing, impacting rates of soil turnover, assisting with nutrient cycling and water infiltration, and creating habitat for other species. The aim of this review is to provide an overview of available information on the habitat and distribution, abundance and threats to bare-nosed wombats (Vombatus ursinus), and to provide a critical review of the current gaps in our knowledge to aid future management of the species. Bare-nosed wombats were previously widespread. Since European settlement their range has reduced. While habitat loss and contraction impact population numbers, bare-nosed wombat populations are also threatened by roadkill, introduced species, legal and illegal human persecution, and disease. Further research is required to understand the historic range of bare-nosed wombats, as well as current population numbers, so that we can determine the threats that most significa...
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Research Interests: Immunology, Stress, Mammalogy, Marsupials, Mammals, and 5 moreComparative Immunology, Blood, Dasyurids, PBMC, and semelparous
Background Wombats are large, nocturnal herbivores that build burrows in a variety of habitats, including grassland communities, and can come into conflict with people. Counting the number of active burrows provides information on the... more
Background Wombats are large, nocturnal herbivores that build burrows in a variety of habitats, including grassland communities, and can come into conflict with people. Counting the number of active burrows provides information on the local distribution and abundance of wombats and could prove to be an important management tool to monitor population numbers over time. We compared traditional ground surveys and a new method employing drones, to determine if drones could be used to effectively identify and monitor bare-nosed wombat burrows. Results We surveyed burrows using both methods in eight 5-ha transects in grassland, that was interspersed with patches of tussock grassland. Ground surveys were conducted by systematically walking transects and searching for burrows. Drone surveys involved programming flights over transects to capture multiple images, from which an orthomosaic image of each transect was produced. These were subsequently viewed using ArcMap to detect burrows. A tot...
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Citizen science websites and mobile applications are credited for their ability to engage members of the public in science and enhance scientific literacy, while operating as a cost-effective, geographically vast data-collection tool.... more
Citizen science websites and mobile applications are credited for their ability to engage members of the public in science and enhance scientific literacy, while operating as a cost-effective, geographically vast data-collection tool. Recruiting participants, tailoring online platforms to users’ needs and harnessing community values are key to creating a successful, sustainable citizen science project. However, few studies have conducted a detailed examination of the recruitment experience when trying to build an engaged and active citizen science audience to assess wildlife diseases in Australia. The present study aimed to determine the most effective methods to recruit and continue to engage citizens to use the tool called WomSAT (Wombat Survey and Analysis Tools). Various marketing techniques were employed to recruit participants. A survey was also disseminated to gain feedback on WomSAT and understand the driving factors behind participation. Participation in the WomSAT project ...
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Expressed coding sequences were identified for the T cell receptors TCRα, TCRβ, TCRγ, TCRδ, TCRμ, and co-receptors CD3ε, CD4, and CD8α in the red-tailed phascogale (Phascogale calura). Expression of these genes was examined in the... more
Expressed coding sequences were identified for the T cell receptors TCRα, TCRβ, TCRγ, TCRδ, TCRμ, and co-receptors CD3ε, CD4, and CD8α in the red-tailed phascogale (Phascogale calura). Expression of these genes was examined in the developing thymus and spleen of pouch young and juvenile individuals to detect any changes in expressionrelative to developmental stages. Transcripts of CD3ε, CD4, TCRδ and TCRμ were first detected in the thorax at 1 day postpartum (dpp), and transcripts of all target genes were detected in the thymus from 3 dpp, and the spleen from 17 dpp. The relative expression of all target genes changed significantly over the course of pouch life and was associated with histological milestones of both the thymus and the spleen. Peak gene expression was observed early in pouch life in the thymus, with a decrease in expression associated with timing of thymic involution, while expression peaked later in the spleen and was associated with the initial differentiation of t...
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Spinifex hopping-mice (Notomys alexis) and plains mice (Pseudomys australis) are able to successfully occupy arid zones of Australia. We studied the digestive parameters and energy assimilation of captive spinifex hopping-mice and plains... more
Spinifex hopping-mice (Notomys alexis) and plains mice (Pseudomys australis) are able to successfully occupy arid zones of Australia. We studied the digestive parameters and energy assimilation of captive spinifex hopping-mice and plains mice. The experiment consisted of six diets fed to the animals for periods of 12days per food type. On a dry matter basis, the plains mice consumed between 2.5 and 7.2% and the hopping-mice between 5.8 and 9.3% of their body mass in food per day. The body mass of the spinifex hopping-mice increased significantly on the sunflower seed diet, while body mass did not change significantly for the plains mice on any diet. Apparent digestibility of macronutrients was similar in the hopping-mice and plains mice when maintained on the same diet, however digestibility of total micronutrients differed. Maintenance energy requirements for the plains mice were 529kJkgd and spinifex hopping-mice 550kJkgd. Spinifex hopping-mice and plains mice are able to exploit ...
Research Interests: Zoology, Australia, Diet, Energy Metabolism, Mice, and 4 moreAnimals, Digestion, Species Specificity, and Murinae
In mammals, interleukin-21 is a member of the common gamma chain cytokine family that also includes IL-2, IL-4, IL-7, IL-9 and IL-15. IL-21 has pleiotropic effects on both myeloid and lymphoid immune cells and as a consequence, the... more
In mammals, interleukin-21 is a member of the common gamma chain cytokine family that also includes IL-2, IL-4, IL-7, IL-9 and IL-15. IL-21 has pleiotropic effects on both myeloid and lymphoid immune cells and as a consequence, the biological actions of IL-21 are broad: regulating both innate and adaptive immune responses and playing a pivotal role in antivi-ral, inflammatory and antitumour cellular responses. While IL-21 genes have been characterized in mammals , birds, fish and amphibians, there are no reports for any marsupial species to date. We characterized the expressed IL-21 gene from immune tissues of two macropod species, the tammar wallaby (Macropus eugenii), a model macropod, and the closely related endangered bridled nailtail wallaby (Onychogalea fraenata). The open reading frame of macropod IL-21 is 462 nucleotides in length and encodes a 153-mer putative protein that has 46% identity with human IL-21. Despite the somewhat low amino acid conservation with other mammals, structural elements and residues essential for IL-21 conformation and receptor association were conserved in the macropod IL-21 predicted peptides. The detection of IL-21 gene expression in T-cell-enriched tissues, combined with analysis of the promotor region of the tammar wallaby gene, suggests that macropod IL-21 is expressed in stimulated T cells but is not readily detected in other cells and tissues. The similarity of gene expression profile and functionally important amino acid residues to eutherian IL-21 makes it unlikely that the differences in Band T-cell responses that are reported for some marsupial species are due to a lack of important functional residues or IL-21 gene expression in this group of mammals.
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Baseline haematology, blood chemistry and acute phase protein parameters have not previously been published for free-ranging eastern grey kangaroos (Macropus giganteus). Eight eastern grey kangaroos, including three adult males, three... more
Baseline haematology, blood chemistry and acute phase protein parameters have not previously been published for free-ranging eastern grey kangaroos (Macropus giganteus). Eight eastern grey kangaroos, including three adult males, three adult females and two subadult males from two different populations, were examined. Assays assessed the antibacterial activity of kangaroo serum against one Gram-positive and three Gram-negative bacteria. The kangaroo serum had a strong antibacterial response to Klebsiella pneumoniae, and moderate responses to Escherichia coli and Staphylococcus aureus. The presence and level of acute phase proteins, haptoglobin and serum amyloid A in kangaroos was investigated. Haptoglobin and serum amyloid A were present in kangaroo serum, but only haptoglobin was elevated in a kangaroo with capture myopathy and necrotic wounds. The findings of this study provide preliminary data on health parameters of free-ranging eastern grey kangaroos. These parameters can be use...
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Macropods are susceptible to capture myopathy. A post mortem examination, and haematological and blood chemistry analysis was conducted on a male eastern grey kangaroo (Macropus giganteus) believed to have capture myopathy. Changes in... more
Macropods are susceptible to capture myopathy. A post mortem examination, and haematological and blood chemistry analysis was conducted on a male eastern grey kangaroo (Macropus giganteus) believed to have capture myopathy. Changes in blood chemistry and necrosis of muscle tissue are the most prevalent sign of myopathy in eastern grey kangaroos.
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Antimicrobial substances in serum include circulating complement proteins and acute phase proteins (APPs). We identified gene sequences for APPs, haptoglobin (Hp), C-reactive protein (CRP) and serum amyloid A (SAA) in marsupial genomes.... more
Antimicrobial substances in serum include circulating complement proteins and acute phase proteins (APPs). We identified gene sequences for APPs, haptoglobin (Hp), C-reactive protein (CRP) and serum amyloid A (SAA) in marsupial genomes. Hp and SAA levels were measured in red-tailed phascogale (Phascogale calura) sera using commercially available assays. Hp levels were higher in males than females, while SAA levels suggest the phascogales used in this study were healthy. Serum was co-cultured with four bacterial species. Bacterial growth was inhibited after incubation at 37°C, however effectiveness differed with bacteria and incubation time. The least amount of bacterial growth was noticed after introduction to K. pneumoniae, and most when introduced to P. aeruginosa. Despite marsupials not having mature immune tissues at birth, and unable to mount specific immune responses, this study suggests other immune strategies, such as APPs in serum likely aid marsupials in their defence against pathogens.
Research Interests: Immunology, Bacteriology, Antimicrobial Peptides, Innate immunity, Marsupials, and 15 moreAntimicrobials, Biological Sciences, Comparative Immunology, Animals, Blood, Antimicrobial activity, Bacteria, C reactive protein, Marsupialia, Immunohaematology, Marsupial Immunology, Acute Phase Proteins, Marsupiales, Australian Marsupials, and Klebsiella pneumoniae
Short-beaked echidnas (Tachyglossus aculeatus) are myrmecophages, or ant and termite insectivore specialists, and replicating their exact diet in captivity is problematic. Diets for captive animals often incorporate raw meat, eggs and cat... more
Short-beaked echidnas (Tachyglossus aculeatus) are myrmecophages, or ant and termite insectivore specialists, and replicating their exact diet in captivity is problematic. Diets for captive animals often incorporate raw meat, eggs and cat food mixed together with water, and vitamin and mineral supplements. These diets have promoted a number of health problems in captive echidnas, such as gastritis, cystitis, gut impaction, obesity, and diarrhea. A manufactured diet was designed and three echidnas from two zoos were transitioned onto this diet to assess the acceptability and digestibility of this diet for echidnas. The new "test" diet was readily accepted by the echidnas with a 1 week transition period. Daily digestible energy intake was 280 kJ kg(-0.75) d(-1) , similar to another myrmecophagous species. Digestibility values were above 74% for all macronutrients. It was determined that this diet was an acceptable replacement for the previous diets and it was decided that th...
Research Interests: Zoology, Diet, Zoo Biology, Animal Feed, Female, and 7 moreAnimals, Digestion, Male, Feces, Veterinary Sciences, Echidna, and Zoo animals
Tyzzer's disease is caused by Clostridium piliformes and affects a wide range of domestic and wildlife species. Non-descript signs, if... more
Tyzzer's disease is caused by Clostridium piliformes and affects a wide range of domestic and wildlife species. Non-descript signs, if any, and a short incubation period make Tyzzer's disease difficult to diagnose and treat before death occurs. Here we describe an unexpected outbreak of Tyzzer's disease in a colony of native Australian spinifex hopping-mice (Notomys alexis). In this study captive hopping-mice were used in a nutrition trial (n=11), and others were housed in close proximity (n=4). During the nutrition trial, two hopping-mice exhibited signs of lethargy and diarrhoea, and were removed from the trial but died soon after. Other hopping-mice exhibited limited clinical signs of ill-health, prior to their death. In total four animals were found dead, and another seven were euthanised, to prevent a potential disease outbreak. Tyzzer's disease was confirmed post-mortem using histopathology silver stain to detect the bacilli-shaped bacteria (C. piliformes) in liver tissue of two hopping-mice. After Tyzzer's disease was confirmed enhanced infection control measures were implemented. Enhanced control measures included the use of metal containers for food and water, sick animals were fed and cleaned last, 5% sodium hypochlorite was used as the cleaning agent, stricter hand washing protocols and a change of gloves between feeding animals, and strict limits on persons entering the facility. Control measures for this disease should include euthanasia of any animals suspected to be infected, complete disinfection of all enclosures and associated equipment using sodium hypochlorite. Molecular methods could be employed to ensure complete removal of bacterial spores prior to new animals being moved into enclosures where affected animals were housed. Tyzzer's disease is a fast spreading disease which can cause detrimental effects to captive colonies and their environment. Captive colonies subjected to stress are at risk of Tyzzer's disease. Appropriate quarantine procedures, close montoring and quick action in response to signs of illness will ensure Tyzzer's disease outbreaks do not occur.
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Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific... more
Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific complement proteins remains largely unexplored. We report partial cDNA sequences for two complement-activating proteins, C3, C1r, CFP and MASP2, in liver tissues from red-tailed phascogale (Phascogale calura). Conservation of functionally relevant motifs were identified in the translated cDNA sequences from phascogale C3, CFP and MASP2 and their eutherian homologues. Gene expression of representative molecules from each of the major complement pathways was also investigated in whole body tissues from 1 to 18 day old animals and liver tissues from 31-day to 14-month old animals. Average complement expression in whole bodies and liver tissues of C1r, CFP, MASP2 and C3 increased significantly in juveniles compared to pouch young, presumably due to the matur...
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Interleukin-10 is an immunomodulatory cytokine that has been implicated, along with IFN-γ, in the disease sequelae of mycobacterial infection. In order to investigate the role of IL-10 in marsupial disease models we sequenced and... more
Interleukin-10 is an immunomodulatory cytokine that has been implicated, along with IFN-γ, in the disease sequelae of mycobacterial infection. In order to investigate the role of IL-10 in marsupial disease models we sequenced and characterised the IL10 gene in the tammar wallaby (Macropus eugenii) and rufous hare-wallaby (Lagorchestes hirsutus). An isoform IL-10Δ3, in which an in-frame deletion of exon 3 occurs, was discovered in both macropod species. Analysis of wallaby and other reported marsupial IL-10 homologs suggests that while marsupial IL-10 is comparable to that of human IL-10, the predicted IL-10Δ3 protein may play a more complicated role in the modulation of IL-10-directed responses. Expression of the canonical gene and splicing variant was confirmed in both wallabies, and the rufous hare-wallaby showed differential expression across lymph node, spleen and liver, with isoform expression detected in the lymph node. This characterisation and expression of IL-10 in de novo ...
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Research Interests: Hematology, Conservation, Australia, Endangered Species, Mammals, and 15 moreHaematology, Small Mammals, Blood, Captive Breeding, Captivity, Australian Native Spices, Captive Husbandry, Captive Welfare, Leukocytes, Blood Biochemistry, Murid, Blood Chemistry, Health parameters, Mesembriomys, and Leporillus
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Captive kultarrs (Antechinomys laniger) were bred from June to February. Their gestation period was longer than 12 days, as suggested by previous research. Pouches were observed to determine whether births occurred. Individuals were... more
Captive kultarrs (Antechinomys laniger) were bred from June to February. Their gestation period was longer than 12 days, as suggested by previous research. Pouches were observed to determine whether births occurred. Individuals were capable of producing offspring in their second and third year of life, which has been suspected previously, but never demonstrated in other published studies.
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Abstract Chironomids or'midges' are regarded by many Australian aquatic scientists with a mixture of suspicion and fear. They are a family of freshwater insects(in the order Diptera) that are sometimes perceived to be tolerant of... more
Abstract Chironomids or'midges' are regarded by many Australian aquatic scientists with a mixture of suspicion and fear. They are a family of freshwater insects(in the order Diptera) that are sometimes perceived to be tolerant of polluted water and often appear to ...
... Glen, AS & Dickman, CR (2006). Diet of the spotted-tailed quoll (Dasyurus maculatus) in eastern Australia: effects of season, sex and size. J. Zool. (Lond.) 269, 241–248. Web of Science® Times Cited: 10. Green, B.,... more
... Glen, AS & Dickman, CR (2006). Diet of the spotted-tailed quoll (Dasyurus maculatus) in eastern Australia: effects of season, sex and size. J. Zool. (Lond.) 269, 241–248. Web of Science® Times Cited: 10. Green, B., King, D. & Bradley, A. (1989). ...
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The complement system is a major mediator of the vertebrate immune system, which functions in both innate and specific immune responses. It comprises more than 30 proteins working to remove foreign cells by way of anaphylatoxins, opsonins... more
The complement system is a major mediator of the vertebrate immune system, which functions in both innate and specific immune responses. It comprises more than 30 proteins working to remove foreign cells by way of anaphylatoxins, opsonins or the membrane attack complex. Over the last few years, whole genome sequences of non-eutherian mammals (marsupials and a monotreme), the gray short-tailed opossum (Monodelphis domestica), tammar wallaby (Macropus eugenii), Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus) and platypus (Ornithorhynchus anatinus), have become publicly available. Using these sequences, we have identified an array of complement components in non-eutherians using online search tools and algorithms. Of 57 complement and complement-related genes investigated, we identified 46 in the gray short-tailed opossum genome, 27 in the tammar wallaby genome, 44 in the Tasmanian devil genome, 47 in the koala genome and 40 in the platypus genome. The results of...
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Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail... more
Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail possums is crucial to understanding the factors limiting their survival, and was the focus of this study. Spotlighting surveys were conducted to locate ringtail possums, and scat and vegetation samples were collected for microhistological analysis. Ringtail possums were most frequently observed in red stringybark followed by bundy box and black cypress pine trees, and this correlated with the most common dietary items consumed.
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Marsupials are a group of mammals that give birth to immature young lacking mature immune tissues at birth, and are unable to mount their own specific immune defence. Their immune tissues develop in a non-sterile ex-utero environment... more
Marsupials are a group of mammals that give birth to immature young lacking mature immune tissues at birth, and are unable to mount their own specific immune defence. Their immune tissues develop in a non-sterile ex-utero environment unlike that of eutherian mammals such as ourselves. Marsupials are therefore ideal models for studying the development of immune tissues, in particular haematopoiesis, yet relatively little has been investigated. Most studies have been restricted to histological or immunohistological studies, however some factors likely to be involved, based on eutherian studies in haematopoiesis, have been isolated and characterised, including a few key markers, and some cell signaling and regulation molecules, mostly involved in lymphocytopoiesis. However the role of many molecules in haematopoiesis is largely presumed. We currently lack much of the rudimentary information regarding time of appearance and expression levels of these molecules, and no functional studies...
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Red-tailed phascogale (Phascogale calura) pouch young at birth were relatively underdeveloped in comparison with their eutherian counterparts, and the lymphoid tissues of the immune system were found to be histologically immature. The... more
Red-tailed phascogale (Phascogale calura) pouch young at birth were relatively underdeveloped in comparison with their eutherian counterparts, and the lymphoid tissues of the immune system were found to be histologically immature. The phascogale thymus rapidly developed in the first few days of pouch life and was quickly populated with lymphocytes. By the end of pouch life, involution of the thymus was underway. The bone marrow started to develop in the early stage of pouch life, although adipocytes and megakaryocytes were not observed until slightly later. The liver was hematopoietic from birth and reached histological maturity toward the end of pouch life. The lymph nodes were difficult to detect macroscopically because of their small size, but were easily identified microscopically later in pouch life, particularly in the mesentery, and these lymph nodes exhibited germinal centers by the end of pouch life. The early spleen was predominately mesenchymal, but exhibited some erythro...
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The thylacine (Thylacinus cynocephalus) was Australia's largest marsupial carnivore until its extinction within the last century. There remains considerable interest and debate regarding the biology of this species. Studies of... more
The thylacine (Thylacinus cynocephalus) was Australia's largest marsupial carnivore until its extinction within the last century. There remains considerable interest and debate regarding the biology of this species. Studies of thylacine biology are now limited to preserved specimens, and parts thereof, as well as written historical accounts of its biology. This study describes the development of the immune tissues of a pouch young thylacine, one of only eleven in existence, and the only specimen to be histologically sectioned. The appearance of the immune tissue of the developing pouch young thylacine is compared to the immune tissues of extant marsupials, providing insights into the immunity, biology and ecology of the extinct thylacine.
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This is the first published description of the lymphoid and immunohaematopoietic tissues of an Australian polyprotodont, the stripe-faced dunnart, Sminthopsis macroura and the first account of bronchus-associated lymphoid tissue (BALT) in... more
This is the first published description of the lymphoid and immunohaematopoietic tissues of an Australian polyprotodont, the stripe-faced dunnart, Sminthopsis macroura and the first account of bronchus-associated lymphoid tissue (BALT) in a metatherian. Histologically, the tissue beds are similar in appearance to those reported in other adult eutherian and metatherian mammals. The liver and bone marrow were mature and virtually no haematopoietic activity was observed. The thymus had undergone involution but retained some lymphocytes. The spleen was similar to that observed in other metatherians containing areas of red and white pulp separated by a marginal zone. Lymph nodes, except for a pair in the posterior abdomen, were difficult to locate but were similar to those observed previously in other adult metatherians. Peyer's patches were present; however, they lacked dome regions and sometimes had villi above them. BALT appeared to be both compartmentalised and non-compartmentalised in the adult stripe-faced dunnart.
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Generally the reporting of diseases and parasites in Australian native murids is rare despite murids making up ~25% of the native mammal fauna of Australia. This paper reports a malignant melanoma in a captive spinifex hopping-mouse... more
Generally the reporting of diseases and parasites in Australian native murids is rare despite murids making up ~25% of the native mammal fauna of Australia. This paper reports a malignant melanoma in a captive spinifex hopping-mouse (Notomys alexis) and is the first case of melanoma reported in any native Australian murid. With no exposure to ultraviolet radiation the melanoma is proposed to be the result of genetic predisposition and age. As no other reports have been observed in the colony it is likely to be a very rare event in captivity and unlikely to occur in the wild.
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Torpor is an important physiological process used to reduce body temperature and thus energy needs in mammals and birds. Rewarming from torpor can be costly. In some small mammals basking is used to reduce the cost of rewarming from... more
Torpor is an important physiological process used to reduce body temperature and thus energy needs in mammals and birds. Rewarming from torpor can be costly. In some small mammals basking is used to reduce the cost of rewarming from torpor. The use and duration of basking was measured in two native Australian marsupials, the red-tailed phascogale (Phascogale calura) and kultarr (Antechinomys laniger), using a heat rock. Animals were observed via video cameras to determine whether they used basking behaviours and whether this behaviour was affected by food availability. Both species became accustomed to the heat rock as time progressed. Absence of food increased basking duration and frequency in some individuals but not all animals. Generally kultarrs basked for longer periods than phascogales, and kultarrs would bask at all hours of the day while phascogales showed a strict nocturnal regime (1900-0700h). The results demonstrate that basking may be an important behavioural adaptation of the kultarr; while the phascogale requires further research.
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Reproduction and especially lactation are nutritionally costly for mammals. Maternal access to adequate and optimal nutrients is essential for fecundity, survival of offspring, and offspring growth rates. In eutherian species energy... more
Reproduction and especially lactation are nutritionally costly for mammals. Maternal access to adequate and optimal nutrients is essential for fecundity, survival of offspring, and offspring growth rates. In eutherian species energy requirements during lactation can be heavily dependent on litter size and the body mass of the female. In marsupials litter size does not appear to affect nutritional requirements during lactation; however, studies of marsupial nutritional requirements during lactation are rare. Marsupials are distinct from eutherians as they give birth to young at a much more underdeveloped state and the majority of their investment into the growth of their offspring occurs postnatally. Nutritional requirements of adult female red-tailed phascogales (Phascogale calura) were measured to determine the differences between those lactating and not lactating. On average females that were lactating had maintenance energy requirements of 1728±195kJkg(-0.75) d(-1), double that of non-lactating animals. There was no significant correlation between energy requirements and litter size among lactating female phascogales. Apparent absorption of macronutrients did not differ between lactating and non-lactating individuals. The study has shown that food needs to be increased by at least double during late lactation. Litter size appears to have no influence on maternal nutrient requirements when food is available ad libitum and offspring in smaller litters grow faster than those in larger litters.
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ABSTRACT Very few assays that are used to assess the status of mammalian immunity have proved useful for assessment of marsupial health and/or diagnosis of disease. This is largely due to the lack of species cross-reactive reagents that... more
ABSTRACT Very few assays that are used to assess the status of mammalian immunity have proved useful for assessment of marsupial health and/or diagnosis of disease. This is largely due to the lack of species cross-reactive reagents that underpin such experiments. To begin to address this deficit, we describe the activation of classical and alternative complement pathways of red-tailed phascogales (RTP; Phascogale calura). Using standard haemolytic assays, the existence of both complement pathways were established in RTP serum based on its ability to lyse unsensitised rabbit erythrocytes (RbE) and sensitised sheep erythrocytes (SE), respectively. The alternative complement pathway assays were conducted using pooled serum of male and female RTPs, and the remaining RTP sera were opportunistically used to test the presence of a functional classical complement system in individual animals, a first in non-eutherian animals. Observations from this study suggest that the activation of these two complement pathways in RTPs are comparable to that seen in other mammals. Since this assay was able to be used on very small samples of blood, it could serve as a useful tool to gather data for comparative immunological studies and to further our knowledge of the mechanisms of immunity available to marsupial young.
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Tasmanian devils are the largest extant marsupial carnivores, confined to the Australian island state of Tasmania. The iconic marsupial has dramatically declined in number since the discovery of devil facial tumor disease in 1996 and... more
Tasmanian devils are the largest extant marsupial carnivores, confined to the Australian island state of Tasmania. The iconic marsupial has dramatically declined in number since the discovery of devil facial tumor disease in 1996 and efforts are being made to uncover vital information to assist in the long-term survival of the species. Ticks are the main vectors of arthropod-borne disease in animals, raising the question of whether Tasmanian devils may be host to arthropods capable of harboring infectious agents. Partially engorged ticks were collected from 35 wild Tasmanian devils and tested for the presence of a range of tick-borne genera. A spotted fever group Rickettsia was detected in 45.5% of samples of the tick Ixodes tasmani (n=44), from all trapping locations, sharing close sequence identity to members of the Rickettsia massiliae group. A Hepatozoon species was also identified in 34.1% of the same sample set, sharing sequence similarities to Hepatozoon felis, a known pathog...
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The lymphoid and immunohaematopoietic tissues of the embryonic and full-term brushtail possums was investigated histologically and immunohistochemically using antibodies to the T- and B-cell markers, CD3, CD5, CD79a and CD79b. No clearly... more
The lymphoid and immunohaematopoietic tissues of the embryonic and full-term brushtail possums was investigated histologically and immunohistochemically using antibodies to the T- and B-cell markers, CD3, CD5, CD79a and CD79b. No clearly defined thymus, bone marrow, spleen, lymph nodes, gut-associated lymphoid tissues or bronchus-associated lymphoid tissues were observed histologically. The liver was haematopoietic and contained erythrocytic and granulocytic precursors. No mature lymphocytes were observed histologically or detected using antibodies to T- and B-cell markers in any of the tissues. These results are consistent with other studies of the early postnatal tissues of other marsupials and support the proposition that neonatal marsupials are substantially reliant on maternal immunological protection at the time of birth and for a significant period of pouch life.
Research Interests: Cognitive Science, Immunohistochemistry, Hematopoiesis, Hematopoietic Stem Cells, Pregnancy, and 14 moreFemale, Animals, Bone marrow, Medical Physiology, T lymphocytes, Veterinary Anatomy and Embryology, Biological markers, B Lymphocytes, Lymph Node, Embryos, Opossums, Neurosciences, Lymphoid Tissue, and Maternal-fetal exchange
Interferon-γ (IFN-γ) is an important immune regulatory molecule that plays a significant role in internal and external modulation of the mammalian immune response to intracellular pathogens. Herein, we report the 492 nt expressed sequence... more
Interferon-γ (IFN-γ) is an important immune regulatory molecule that plays a significant role in internal and external modulation of the mammalian immune response to intracellular pathogens. Herein, we report the 492 nt expressed sequence for the coding domain of IFN-γ from the immune tissues of two Australian macropod marsupial species: the tammar wallaby (Macropus eugenii) and the vulnerable rufous hare-wallaby (Lagorchestes hirsutus). Both 5' and 3' untranslated regions and the coding domain of M. eugenii IFN-γ revealed the presence of motifs responsible for transcriptional regulation, mRNA regulation, post-translational modifications, and receptor binding in other mammals. Since diagnostic kits for mycobacterial disease commonly rely on the assessment of interferon levels, we can now use this information to develop reagents that can be applied in clinical and laboratory settings to further our understanding of marsupial responses to disease.
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Chironomids or'midges' are regarded by many Australian aquatic scientists with a mixture of suspicion and fear. They are a family of freshwater insects(in the order Diptera) that are sometimes perceived to be tolerant of polluted... more
Chironomids or'midges' are regarded by many Australian aquatic scientists with a mixture of suspicion and fear. They are a family of freshwater insects(in the order Diptera) that are sometimes perceived to be tolerant of polluted water and often appear to ...
Tasmanian devils are the largest extant marsupial carnivores, confined to the Australian island state of Tasmania. The iconic marsupial has dramatically decline.
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The kultarr (Antechinomys laniger) is a small marsupial that inhabits arid and semi-arid areas of central Australia. The kultarr is the only species within its genus and is morphologically unique from other dasyurids. Like many Australian... more
The kultarr (Antechinomys laniger) is a small marsupial that inhabits arid and semi-arid areas of central Australia. The kultarr is the only species within its genus and is morphologically unique from other dasyurids. Like many Australian marsupials, the kultarr has undergone significant population declines and although it is listed as "least concern" on the IUCN red list little is known of their ecology in the wild. A lack of knowledge on their biology can be attributed to their cryptic nature and sparse population densities. Recent studies of kultarrs have increased knowledge of the biology and captive management, with current data predominately coming from captive colonies. Captive studies of the kultarr have provided data on reproduction, diet choice, nutrition, health, and disease. Kultarrs are polyestrous seasonal breeders and are believed to be mostly insectivorous. Diseases noted in captive individuals provide some insight into those that may influence animals in the wild. Further research is required on both wild and captive populations to increase the knowledge base and determine appropriate management techniques for both wild and captive populations.
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The eastern quoll (Dasyurus viverrinus) is a carnivorous Australian marsupial that has undergone significant geographical range contraction since European settlement, and is extinct on the mainland. Nutrition is not well researched in... more
The eastern quoll (Dasyurus viverrinus) is a carnivorous Australian marsupial that has undergone significant geographical range contraction since European settlement, and is extinct on the mainland. Nutrition is not well researched in captive eastern quolls, and captive diets often consist of commercial pet foods as opposed to raw meat or insect diets. Improving nutrition will enhance reproductive output and ensure suitable numbers of quolls are bred to be used in translocation programs. The present study analyzed the composition of kangaroo mince and chicken necks, and the digestibility of these items, in a captive environment. The quolls had high apparent total tract digestibility on the chicken neck and kangaroo mince treatments (DM 83-88%, GE 95-97%, protein 94-97%, and lipids 94-95%, respectively). The apparent total tract digestibility of DM, GE, and proteins was significantly higher (t14= 2.465, P < 0.05; t14= 2.489, P < 0.05; t14= 5.470, P < 0.01, respectively) on the kangaroo mince treatment compared with the chicken neck treatment. This study provides the first data on Cu (-18-37%), S (86-95%), and Zn (26-28%) apparent total tract digestibility in a Dasyurid. Data gathered during this study can be used to improve management practices for captive quolls, including diet formulation and mineral supplementation.
Research Interests: Zoology, Diet, Zoo Biology, Animal Feed, Animals, and 6 moreDigestion, Meat, Marsupialia, Chickens, Veterinary Sciences, and Zoo animals
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Research Interests: Zoology, Veterinary, Phylogeny, Animals, Antimicrobial Peptide, and 12 moreMacropodidae, Antimicrobial Cationic Peptides, Mammary gland, Gastrointestinal Tract, Veterinary Sciences, Veterinary Immunology, Amino Acid Sequence, Base Sequence, Reverse Transcriptase, Gene Expression Regulation, Innate Immune System, and Molecular Sequence Data
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The Eastern and Spotted-Tailed Quolls are... more
The Eastern and Spotted-Tailed Quolls are "near threatened" Australian dasyurid marsupials that have undergone significant reduction in their geographic ranges in the past 200 years. Captive breeding and research colonies now exist, allowing further efforts to more fully understand the physiology of these carnivorous species. The aims of the study were to provide a more detailed study of blood chemistry and differential WBC counts for Eastern and Spotted-Tailed Quolls, and to determine the influence by 3 biologic factors. Blood samples were taken from conscious, captive, healthy Eastern Quolls. A small number of samples from Spotted-Tailed Quolls were also available and were included in the study for comparison. Blood chemistry and differential WBC counts were compared to determine season-, age-, and sex-related differences. For many of the analytes, blood chemistry results were comparable to other marsupial ranges, and no significant differences between sexes were detected (P > .05). Seasonal differences were determined for total bilirubin, glucose, creatinine, and potassium concentrations in the Eastern Quoll. Generally, higher concentrations of these analytes were observed in the summer; however, amylase activity was significantly higher in autumn (southern hemisphere). Eastern Quolls one year of age and younger had significantly (P < .05) higher ALP activities than older animals. The normal ranges determined in this study can be used to assess clinical health of quolls and will assist with captive management and future reintroduction programs to the wild.
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A total of 42 ticks comprising Ixodes tasmani (n = 41) and Ixodes trichosuri (n = 1) were collected from wild koalas (Phascolarctos cinereus) at the Koala Convention Centre, Philip Island, Victoria, Australia and screened for the presence... more
A total of 42 ticks comprising Ixodes tasmani (n = 41) and Ixodes trichosuri (n = 1) were collected from wild koalas (Phascolarctos cinereus) at the Koala Convention Centre, Philip Island, Victoria, Australia and screened for the presence of Bartonella using the target gene gltA. Bartonella-like DNA was detected in 4 of the 19 pooled tick samples (21%). All positive ticks were male. Analysis of partial sequences for the gltA gene indicated the presence of a Bartonella-related species similar to that reported in another Ixodid species. This is the first report of Bartonella-like organisms in a native Australian marsupial.
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Research Interests: Immunohistochemistry, Antimicrobials, Antibodies, Humans, Female, and 15 moreAnimals, Male, Bone marrow, Medical Physiology, Antimicrobial Peptide, Immune system, Macropodidae, Antimicrobial Cationic Peptides, Epithelium, Gastrointestinal Tract, Age Factors, Amino Acid Sequence, Epitopes, Biochemistry and cell biology, and Molecular Sequence Data
Incubation temperature affects developmental rates and defines many phenotypes and fitness characteristics of reptilian embryos. In turtles, eggs are deposited in layers within the nest, such that thermal gradients create independent... more
Incubation temperature affects developmental rates and defines many phenotypes and fitness characteristics of reptilian embryos. In turtles, eggs are deposited in layers within the nest, such that thermal gradients create independent developmental conditions for each egg. Despite differences in developmental rate, several studies have revealed unexpected synchronicity in hatching, however, the mechanisms through which synchrony are achieved may be different between species. Here, we examine the phenomenon of synchronous hatching in turtles by assessing proximate mechanisms in an Australian freshwater turtle (Emydura macquarii). We tested whether embryos hatch prematurely or developmentally compensate in response to more advanced embryos in a clutch. We established developmental asynchrony within a clutch of turtle eggs and assessed both metabolic and heart rates throughout incubation in constant and fluctuating temperatures. Turtles appeared to hatch at similar developmental stages, with less-developed embryos in experimental groups responding to the presence of more developed eggs in a clutch by increasing both metabolic and heart rates. Early hatching did not appear to reduce neuromuscular ability at hatching. These results support developmental adjustment mechanisms of the 'catch-up hypothesis' for synchronous hatching in E. macquarii and implies some level of embryo-embryo communication. The group environment of a nest strongly supports the development of adaptive communication mechanisms between siblings and the evolution of environmentally cued hatching.
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This paper reports on the isolation and identification of the fur-clasping mite, Myocoptes musculinus, from the faeces of the Spinifex Hopping mouse (Notomys alexis). This investigation adds to the sparse records of ectoparasites... more
This paper reports on the isolation and identification of the fur-clasping mite, Myocoptes musculinus, from the faeces of the Spinifex Hopping mouse (Notomys alexis). This investigation adds to the sparse records of ectoparasites collected from native Australian murids.
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... Glen, AS & Dickman, CR (2006). Diet of the spotted-tailed quoll (Dasyurus maculatus) in eastern Australia: effects of season, sex and size. J. Zool. (Lond.) 269, 241–248. Web of Science® Times Cited: 10. Green, B.,... more
... Glen, AS & Dickman, CR (2006). Diet of the spotted-tailed quoll (Dasyurus maculatus) in eastern Australia: effects of season, sex and size. J. Zool. (Lond.) 269, 241–248. Web of Science® Times Cited: 10. Green, B., King, D. & Bradley, A. (1989). ...
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Current knowledge of the development of the marsupial immune system, particularly in the context of lymphoid tissue development and the appearance of lymphocytes, has been examined and limitations identified. While primary lymphoid... more
Current knowledge of the development of the marsupial immune system, particularly in the context of lymphoid tissue development and the appearance of lymphocytes, has been examined and limitations identified. While primary lymphoid tissues like the thymus have been extensively studied, secondary lymphoid tissues such as the spleen and lymph nodes have been examined to a lesser extent, partly due to the difficulty of macroscopically identifying these structures, particularly in very small neonates. In addition, little research has been conducted on the mucosal-associated lymphoid tissues; tissues that directly trap antigens and play an important role in the maturity of adaptive immune responses. Research on the development of the marsupial immune tissues to date serves as a solid foundation for further research, particularly on the mechanisms behind the development of the immune system of marsupials. With the recent sequencing and annotation of whole marsupial genomes, the current wealth of sequence data will be essential in the development of marsupial specific reagents, including antibodies, that are required to widen our specific knowledge of the complex marsupial immune system and its development.
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ABSTRACT Four species of Rickettsia are recognized as endemic to Australia. This study reports the detection of a new spotted fever group Rickettsia in the common marsupial tick Ixodes tasmani Neumann collected from koalas (Phascolarctos... more
ABSTRACT Four species of Rickettsia are recognized as endemic to Australia. This study reports the detection of a new spotted fever group Rickettsia in the common marsupial tick Ixodes tasmani Neumann collected from koalas (Phascolarctos cinereus) in Port Macquarie, NSW, Australia. Based on the results of polymerase chain reaction (PCR) amplification of extracted tick DNA with primers targeting the citrate synthase gene (gltA) and the outer membrane proteins A and B (ompA. ompB), Rickettsiae were detected in 22 of 78 I. tasmani tick samples (28.2%). Sequence data obtained for the three genes displayed the closest degree of similarity to Rickettsia heilongjiangiensiss for gltA (99.4%; 331/333 bp), Rickettsia amblyommii for the ompA gene (94.8%; 417/440 bp), and both Rickettsia massiliae and Rickettsia rhipicephali for the ompB gene (97%; 770/803 bp). BLAST and phylogenetic analysis of partial sequences obtained for the three genes were found to have sufficient nucleotide variation from the current recognized Australian species to be considered a distinct spotted fever group Rickettsia.
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ABSTRACT Ticks (n = 252) were collected from five wild-caught reptile species during routine trapping in the Djukbinj National Park and Fogg Dam Reserve, Northern Territory, Australia. Pooling of ticks (one to four ticks per pool),... more
ABSTRACT Ticks (n = 252) were collected from five wild-caught reptile species during routine trapping in the Djukbinj National Park and Fogg Dam Reserve, Northern Territory, Australia. Pooling of ticks (one to four ticks per pool), according to sex or host animal, resulted in 187 samples used for screening for the presence of Rickettsia species via molecular methods. Rickettsia DNA was detected via the amplification of the gltA, ompA, and ompB genes in 57 (34%) of the 187 tick samples, all of which contained only the tick Amblyomma fimbriatum Koch (Acari: Ixodidae). Further amplification and sequencing of nine of the positive samples (4.8%) for the gltA, ompA, ompB, 17-kDa, and 16S rRNA genes identified a Rickettsia species sharing closest identity to Rickettsia tamurae. In addition, amplification and sequencing of the 16S rRNA gene detected in the same tick samples the presence of a Francisella species closely related to other tick-borne Francisellae identified in ticks from the Northern Hemisphere.
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Research Interests: Zoology, Australia, Ticks, DNA, Phylogeny, and 14 moreParasite, Female, Animals, Male, Bacteria, VECTOR, Marsupialia, Bacterial Diversity, Genotype, Echidna, Native Species, Rickettsia, Hosts, and Phascolarctidae
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The development of the liver, bone marrow and spleen have been investigated in the stripe-faced dunnart. At birth, the liver was undergoing haematopoiesis but the level declined rapidly and by day 50 after birth the liver was... more
The development of the liver, bone marrow and spleen have been investigated in the stripe-faced dunnart. At birth, the liver was undergoing haematopoiesis but the level declined rapidly and by day 50 after birth the liver was histologically mature. Both the bone marrow and spleen were non-haematopoietic at birth but initiated haematopoiesis shortly thereafter. Bone marrow was initially detected at day 11 postpartum. By 57 days after birth, adipocytes had infiltrated the marrow and were abundant by day 60 after birth. Mitotic cells were observed in remaining areas of marrow until at least 170 days postpartum. The spleen at birth was undifferentiated, with trabeculae appearing by day 42. Red and white pulp areas became apparent by day 43 and were well defined by day 57 after birth. In summary, the pattern of the development of the liver, bone marrow and spleen in the stripe-faced dunnart were similar to that observed in eutherians and other metatherians studied to date.
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ABSTRACT Ectoparasites were collected from 32 wild spotted-tailed quolls (Dasyurus maculatus) trapped in the Tuggolo State Forest, New South Wales, Australia, during February and March 2005. Species collected included 2 ixodid ticks, 2... more
ABSTRACT Ectoparasites were collected from 32 wild spotted-tailed quolls (Dasyurus maculatus) trapped in the Tuggolo State Forest, New South Wales, Australia, during February and March 2005. Species collected included 2 ixodid ticks, 2 sarcoptiform mites, and 5 fleas from the families Pygiopsyllidae and Stephanocircidae. The presence of a mange-like skin condition was observed in several of the animals during trapping, evidenced by pruritic dermatitis and alopecia on the limbs, tail, rump, and face. A biopsy taken of the muzzle region of a male quoll displaying mange-like features and subsequent histological examination revealed the presence of marked acanthosis, hyperkeratosis, and eosinophilic infiltration. Uropsylla tasmanica larvae were observed encapsulated by collagenous fibrous tissue. Dasyurochirus nr. major mites encapsulated in eggs were also observed attached to hair on the skin surface of the biopsy material. The histological evidence supports the proposition that the mange-like condition is the combined result of multiple ectoparasite infestations and environmental stressors.
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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... more
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 organisms including Corynebacterium spp., Micrococcus spp. and Staphylococcus spp. were the most frequent isolates, regardless of reproductive status. Whilst Gram-negative rods Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes, and Escherichia coli were found in pouches with and without pouch young, but not in pouches close to oestrus, at the time of birth or in the presence of very young animals (< 6 days). While pouches without pouch young displayed the greatest diversity of bacterial species, there were still significant numbers of bacterial species in those containing pouch young. Results suggest that the microbial population of the tammar pouch does not seriously compromise the well-being of the young animal during crucial stages of immunological development. The data are consistent with observations on the microflora of the quokka pouch but not with data from the koala.
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... alexis) and the Central Rock-rat, (Zyzomys pedunculatus). Comp Clin Pathol 14:130137 Oyewale JO, Olayemi FO, Oke OA (1998) Haematology of the wild adult African giant rat (Cricetomys gambianus, Waterhouse). Veterinarski Arh 68:9199... more
... alexis) and the Central Rock-rat, (Zyzomys pedunculatus). Comp Clin Pathol 14:130137 Oyewale JO, Olayemi FO, Oke OA (1998) Haematology of the wild adult African giant rat (Cricetomys gambianus, Waterhouse). Veterinarski Arh 68:9199 Puckey H, Woinarski J, Trainor C ...
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A proteomic analysis of neutrophils from the tammar wallaby, Macropus eugenii, has been performed. Neutrophils were isolated from peripheral blood using density gradient centrifugation with Histopaque-1077, followed by treatment with... more
A proteomic analysis of neutrophils from the tammar wallaby, Macropus eugenii, has been performed. Neutrophils were isolated from peripheral blood using density gradient centrifugation with Histopaque-1077, followed by treatment with ammonium chloride to lyse residual erythrocytes. Two-dimensional gel electrophoresis (2-DE) of lysed neutrophils was undertaken followed by in-gel trypsin digest and nanoliquid chromatography coupled tandem mass spectrometry (LC-MS) analysis and database searches. Seventy-seven proteins were isolated, 53 of which could be identified with high confidence as primarily of cytosolic origin. Protein identifications were only possible by matching identical peptide sequences within the NCBInr mammalian database with the Mascot search program. Sequence identities were only deemed acceptable if more than three peptides were identified, the precursor/protein ion tolerances were less than +/-0.25 Da and the total Mowse scores were greater than 100. The validity of this approach was tested using a scrambled database where no single identified peptide showed Mowse scores greater than 55. This is the first report of the neutrophil proteins of any marsupial and represents a first step in examining the identity of proteins involved in innate defence in this marsupial.
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The development of the lymphoid tissues of a model marsupial, the stripe-faced dunnart, has been described from birth to weaning, a period of 2.5 months. At birth the lymphoid tissues, including the thymus, lymph nodes and... more
The development of the lymphoid tissues of a model marsupial, the stripe-faced dunnart, has been described from birth to weaning, a period of 2.5 months. At birth the lymphoid tissues, including the thymus, lymph nodes and mucosa-associated lymphoid tissues, were undeveloped. A thoracic thymus consisting primarily of stromal tissue was observed by day 4 after birth but by day 12, lymphocytes were observed in the thymus and some cortico-medullary differentiation was apparent. Lymph nodes were histologically mature by day 31, the earliest day investigated for this tissue. In gut tissue, lymphoid follicles were first observed by day 57 post-partum. No bronchus-associated lymphoid tissue was observed in any lung samples. The thymus, lymph nodes and gut-associated lymphoid tissues were all distinguishable before weaning (day 70) but not all were histologically mature. The sequence of development of the lymphoid tissues in the stripe-faced dunnart was similar to those observed in other marsupial species.
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This is the first published description of the lymphoid and immunohaematopoietic tissues of an Australian polyprotodont, the stripe-faced dunnart, Sminthopsis macroura and the first account of bronchus-associated lymphoid tissue (BALT) in... more
This is the first published description of the lymphoid and immunohaematopoietic tissues of an Australian polyprotodont, the stripe-faced dunnart, Sminthopsis macroura and the first account of bronchus-associated lymphoid tissue (BALT) in a metatherian. Histologically, the tissue beds are similar in appearance to those reported in other adult eutherian and metatherian mammals. The liver and bone marrow were mature and virtually no haematopoietic activity was observed. The thymus had undergone involution but retained some lymphocytes. The spleen was similar to that observed in other metatherians containing areas of red and white pulp separated by a marginal zone. Lymph nodes, except for a pair in the posterior abdomen, were difficult to locate but were similar to those observed previously in other adult metatherians. Peyer's patches were present; however, they lacked dome regions and sometimes had villi above them. BALT appeared to be both compartmentalised and non-compartmentalised in the adult stripe-faced dunnart.
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This paper provides a macro- and microscopic description of the digestive tract of the kultarr (Antechinomys laniger), a small dasyurid marsupial. The digestive tract was simple, with no external differentiation between the small and... more
This paper provides a macro- and microscopic description of the digestive tract of the kultarr (Antechinomys laniger), a small dasyurid marsupial. The digestive tract was simple, with no external differentiation between the small and large intestine, and lacked a caecum. Mean gross length of the kultarr digestive tract was 165.2 ± 32.1 mm. Microscopically, the tissues had cell types similar to those of other mammals. The new information will aid future post-mortem investigations of captive kultarrs and future studies of nutrition.
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Captive kultarrs (Antechinomys laniger) were bred from June to February. Their gestation period was longer than 12 days, as suggested by previous research. Pouches were observed to determine whether births occurred. Individuals were... more
Captive kultarrs (Antechinomys laniger) were bred from June to February. Their gestation period was longer than 12 days, as suggested by previous research. Pouches were observed to determine whether births occurred. Individuals were capable of producing offspring in their second and third year of life, which has been suspected previously, but never demonstrated in other published studies.
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This paper reports successful breeding by 4-year-old female red-tailed phascogales (Phascogale calura) and that they can survive until at least 5 years of age in captivity, whilst males can survive until at least 2 years of age in... more
This paper reports successful breeding by 4-year-old female red-tailed phascogales (Phascogale calura) and that they can survive until at least 5 years of age in captivity, whilst males can survive until at least 2 years of age in captivity. These findings have implications for captive breeding programs, providing evidence that older females can be successfully bred. In the longer term we hope these findings may aid conservation efforts of this endangered dasyurid.
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The common ringtail possum (Pseudocheirus peregrinus) is considered abundant throughout its distribution in eastern Australia but appears to be declining at a regional level in inland New South Wales. Previous studies of the common... more
The common ringtail possum (Pseudocheirus peregrinus) is considered abundant throughout its distribution in eastern Australia but appears to be declining at a regional level in inland New South Wales. Previous studies of the common ringtail possum in south-eastern Australia have focussed on coastal populations and little is known about the ecology of inland populations. In south-western Australia studies of the closely related western ringtail possum (Pseudocherius occidentalis) have found that coastal populations differ from inland populations, particularly in their nesting behaviour. In this preliminary study of an inland population of the common ringtail possum at Black Rock Ridge in central west New South Wales population density has been estimated and the habitat and nesting preference assessed. Up to one ringtail per hectare and 4.5 ringtails per spotlight hour were recorded. Tree hollows appeared to be the preferred nest site, with possums seen entering hollows during spotlig...
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Marsupial immune responses were previously touted as ‘primitive’ but we now know that the marsupial immune system is complex and on par with that of eutherian mammals. In this manuscript we review the field of marsupial immunology,... more
Marsupial immune responses were previously touted as ‘primitive’ but we now know that the marsupial immune system is complex and on par with that of eutherian mammals. In this manuscript we review the field of marsupial immunology, focusing on basic anatomy, developmental immunology, immunogenetics and evolution. We concentrate on advances to our understanding of marsupial immune gene architecture, made possible by the recent sequencing of the opossum, tammar wallaby and Tasmanian devil genomes. Characterisation of immune gene sequences now paves the way for the development of immunological assays that will allow us to more accurately study health and disease in marsupials.
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Digestibility was studied in the red-tailed phascogale (Phascogale calura) and the kultarr (Antechinomys laniger), small insectivorous/carnivorous marsupials, to determine their nutrient requirements in captivity. The marsupials were fed... more
Digestibility was studied in the red-tailed phascogale (Phascogale calura) and the kultarr (Antechinomys laniger), small insectivorous/carnivorous marsupials, to determine their nutrient requirements in captivity. The marsupials were fed a range of insects, rat (Rattus rattus) and small carnivore food (Wombaroo). Digestibility experiments were conducted for a total of 12 days, which incorporated a five-day adjustment phase followed by a seven-day collection period. The apparent digestibility values for the phascogale and kultarr were above 81% for dry matter, energy, protein and lipids on all diets provided. No significant difference was found between phascogales and kultarrs on the same diet with respect to apparent digestibility of dry matter, energy, protein and lipids. The apparent absorption of minerals varied for each diet for the phascogale and kultarr. Maintenance energy requirements were determined to be 954 kJ kg0.75 day–1 for the red-tailed phascogale and 695 kJ kg0.75 da...
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The kultarr (Antechinomys laniger) is a small insectivorous marsupial that has undergone significant declines in geographical range. Limited studies have been undertaken on kultarr biology and therefore there is a lack of understanding of... more
The kultarr (Antechinomys laniger) is a small insectivorous marsupial that has undergone significant declines in geographical range. Limited studies have been undertaken on kultarr biology and therefore there is a lack of understanding of its basic biological and ecological requirements. Rate of passage in the kultarr, determined using mealworm cuticle as a marker in minced beef, was 1.6 ± 0.2 h and mean retention time was 3.9 ± 1.2 h. The rapid transit time was consistent for an animal of equivalent body mass, dietary preference and gastrointestinal tract morphology. Mean retention time was short, similar to that of other mammals with a small body mass. This study provides the first insight into gastrointestinal physiology of the little known kultarr.
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ABSTRACT T he Platypus, like other native mammals, has been affected by European settlement. Degradation of natural habitats and landscapes has reduced population numbers and most likely contributed to the extinction of wild Platypus in... more
ABSTRACT T he Platypus, like other native mammals, has been affected by European settlement. Degradation of natural habitats and landscapes has reduced population numbers and most likely contributed to the extinction of wild Platypus in South Australia. A constructed wetland located at Warrawong Sanctuary in South Australia was assessed for its capacity to sustain a resident population of Platypus. This study incorporated surveys of riparian vegetation, water quality and the primary food source of Platypus (macroinvertebrates). The constructed system consisted of four main pools and several riffle zones; the vegetation was mostly native including Eucalyptus and Acacia species. Water quality was poor, with elevated levels of nutrients and turbidity. Macroinvertebrates consisted of a large variety of Platypus prey items. The macroinvertebrates identified suggest that the water quality was poor given the average SIGNAL score obtained. These indicators associated with the quality and structure of the ecosystem at Warrawong were comparable to natural wetlands. Although the system was found to be 'degraded', it was still able to sustain a functional population of Platypus over a 20 year period. (Faragher et al. 1979). Although the Platypus is not considered at risk of extinction, availability of suitable habitat and a continuous food supply are important factors for their survival. Threats from human-induced impacts have reduced numbers in the past, but the species has made a successful comeback through conservation efforts in the eastern states of Australia (Scott & Grant 1997). Current research suggests that Platypus abundance and d i s t r i b u t i o n r e l i e s o n d e f i n e d a q u a t i c h a b i t a t characteristics, including consolidated banks, overhanging vegetation and relatively shallow water (Gust & Handasyde 1995; Ellem et al. 1998; Grant & Temple-Smith 1998; Grant 2007). These preferred habitat characteristics have been altered, in some places extensively, since European settlement. Activities such as agriculture, urban development, forestry and dam construction are particularly threatening to Platypus and their habitat (Grant & Temple-Smith 2003). The adverse effects of these activities include long-term damage to the natural ecosystem, such as bank erosion, removal of vegetation and an influx into waterways of organic and non-organic pollution. These pressures, combined with competition and disease associated with the introduction of exotic pest species, are viewed as a direct threat to the long-term viability of this species (Williams 2000).
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Much of the literature on wombat diet is concerned only with the broad categories of consumed matter, and there is little about their specific nutritional requirements despite diet playing a major role in health. This study gathered... more
Much of the literature on wombat diet is concerned only with the broad categories of consumed matter, and there is little about their specific nutritional requirements despite diet playing a major role in health. This study gathered information by surveying zoological parks and wildlife carers about current feeding regime, diet and the prevalence of nutritional or dental disorders of wombats held in captivity, with the aim of improving the diets of captive wombats, thus their health and welfare outcomes. Data on the composition, variation and basis of diets for 31 bare-nosed or common wombats (Vombatus ursinus) and 19 southern hairy-nosed wombats (Lasiorhinus latifrons) were gathered from 13 facilities. The nutritional values of diets fed to wombats in captivity were calculated and compared with known dietary requirements for bare-nosed wombats. Results demonstrate that the current diet of wombats held in captivity often consists of a high portion of fruits, vegetables and livestock feed, with the fruit and vegetable portions providing higher levels of simple carbohydrates and starch compared with natural grass diets. Generally, the facilities are providing diets that are exceeding reported maintenance energy and nitrogen requirements. Due to a lack of details provided regarding quantity and species of grasses fed, we could not provide an accurate ration calculation for the proportion of grasses in the diets. Some of the health concerns noted included insufficient weight gain, endoparasites, malocclusion and insufficient tooth wear. Further research is required to assess the requirements of reproductive, lactating and juvenile wombats; however, it is clear that wombats in captivity need to be fed larger volumes and varieties of grasses, forbs and sedges than they are currently being fed to maintain good health.
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Hearing is essential for communication, to locate prey and to avoid predators. We addressed the paucity of information regarding hearing in Australian native mammals by specifically assessing the hearing range and sensitivity of the... more
Hearing is essential for communication, to locate prey and to avoid predators. We addressed the paucity of information regarding hearing in Australian native mammals by specifically assessing the hearing range and sensitivity of the red-tailed phascogale (Phascogale calura), the kultarr (Antechinomys laniger) and the spinifex hopping-mouse (Notomys alexis). Auditory brainstem response (ABR) audiograms were used to estimate hearing thresholds within the range of 1-84 kHz, over a dynamic range of 0-80 dB sound pressure level (SPL). Phascogales had a hearing range of 1-40 kHz, kultarrs 1-35 kHz and hopping-mice 1-35 kHz, with a dynamic range of 17-59 dB SPL, 20-80 dB SPL and 30-73 dB SPL, respectively. Hearing for all species was most sensitive at 8 kHz. Age showed no influence on optimal hearing, but younger animals had more diverse optimal hearing frequencies. There was a relationship between males and their optimal hearing frequency, and greater interaural distances of individual males may be related to optimal hearing frequency. Because nocturnal animals use high-range hearing for prey or predator detection, our study suggests this may also be the case for the species examined in this study. Future studies should investigate their vocalizations and behaviour in their natural environments, and by exposing them to different auditory stimuli. ADDITIONAL KEYWORDS: auditory brain response-ear-interaural distance-marsupial-murid-sound.
Mosquito-borne viruses are well recognized as a global public health burden amongst humans, but the effects on non-human vertebrates is rarely reported. Australia, houses a number of endemic mosquito-borne viruses, such as Ross River... more
Mosquito-borne viruses are well recognized as a global public health burden amongst humans, but the effects on non-human vertebrates is rarely reported. Australia, houses a number of endemic mosquito-borne viruses, such as Ross River virus, Barmah Forest virus, and Murray Valley encephalitis virus. In this review, we synthesize the current state of mosquito-borne viruses impacting non-human vertebrates in Australia, including diseases that could be introduced due to local mosquito distribution. Given the unique island biogeography of Australia and the endemism of vertebrate species (including macropods and monotremes), Australia is highly susceptible to foreign mosquito species becoming established, and mosquito-borne viruses becoming endemic alongside novel reservoirs. For each virus, we summarize the known geographic distribution, mosquito vectors, vertebrate hosts, clinical signs and treatments, and highlight the importance of including non-human vertebrates in the assessment of future disease outbreaks. The mosquito-borne viruses discussed can impact wildlife, livestock, and companion animals, causing significant changes to Australian ecology and economy. The complex nature of mosquito-borne disease, and challenges in assessing the impacts to non-human vertebrate species, makes this an important topic to periodically review.
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Background: Ticks are obligate haematophagous ectoparasites of vertebrate hosts and transmit the widest range of pathogenic organisms of any arthropod vector. Seven tick species are known to feed on bare-nosed wombats (Vom-batus ursinus),... more
Background: Ticks are obligate haematophagous ectoparasites of vertebrate hosts and transmit the widest range of pathogenic organisms of any arthropod vector. Seven tick species are known to feed on bare-nosed wombats (Vom-batus ursinus), in addition to the highly prevalent Sarcoptes scabiei mite which causes fatal sarcoptic mange in most bare-nosed wombat populations. Little is known about the pathogens carried by most wombat ticks or how they may impact wombats and wombat handlers. Methods: Wombat ticks were sourced from wildlife hospitals and sanctuaries across Australia and identified to species level using taxonomic keys. Genomic DNA was extracted from a subsample, and following the amplification of the bacterial 16S rRNA gene V3-V4 hypervariable region, next-generation sequencing (NGS) on the Illumina MiSeq platform was used to assess the microbial composition. Results: A total of 447 tick specimens were collected from 47 bare-nosed wombats between January 2019 and Janu-ary 2020. Five species of ticks were identified comprising wombat tick Bothriocroton auruginans (n = 420), wallaby tick Haemaphysalis bancrofti (n = 8), bush tick Haemaphysalis longicornis (n = 3), common marsupial tick Ixodes tasmani (n = 12), and Australian paralysis tick Ixodes holocyclus (n = 4). Tick infestations ranged from one to 73 ticks per wombat. The wombat tick was the most prevalent tick species comprising 94% of the total number of samples and was present on 97.9% (46/47) of wombat hosts. NGS results revealed the 16S rRNA gene diversity profile was predominantly Proteobacteria (55.1%) followed by Firmicutes (21.9%) and Actinobacteria (18.4%). A species of Coxiella sharing closest sequence identity to Coxiella burnetii (99.07%), was detected in 72% of B. auruginans and a Rickettsiella endosymbiont dominated the bacterial profile for I. tasmani. Conclusions: A new host record for H. longicornis is the bare-nosed wombat. One adult male and two engorged adult female specimens were found on an adult male wombat from Coolagolite in New South Wales, and more specimens should be collected to confirm this host record. The most prevalent tick found on bare-nosed wombats was B. auruginans, confirming previous records. Analysis of alpha-diversity showed high variability across both sample locations and instars, similar to previous studies. The detection of various Proteobacteria in this study highlights the high bacterial diversity in native Australian ticks.
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Wombats suffer from sarcoptic mange, a mite infection that ultimately leads to their death from secondary infections. In 2017, wildlife carers were granted legal approval to treat bare-nosed wombats (Vombatus ursinus) for sarcoptic mange... more
Wombats suffer from sarcoptic mange, a mite infection that ultimately leads to their death from secondary infections. In 2017, wildlife carers were granted legal approval to treat bare-nosed wombats (Vombatus ursinus) for sarcoptic mange in the field using 4 mL of topical Cydectin® per adult wombat. However, (limited) scientific field trials suggest approved protocols are inadequate which has been supported anecdotally by wildlife carers. Elucidating carer experience is key to holistically advancing under-standings of sarcoptic mange treatment. We interviewed 18 wildlife carers regarding the use of Cydectin® to treat free-ranging adult wombats infected with sarcoptic mange which uncovered 43 detailed case studies for examination. Case studies revealed that wildlife carers have used 10-200-mL doses of topical Cydectin® to treat wombats to recovery. These results suggest there is no best-fit for treating wombats in the field, due to individual differences in observed levels of sarcoptic mange severity and differences in wombat behavior. Furthermore, wildlife carers suggested pour-on Cydectin® appeared non-toxic to wombats at rates as high as 200 mL per treatment. We recommend scientific trials should be undertaken to determine the impact and efficacy of the varying treatment regimens, including low and high doses of topical Cydectin® on bare-nosed wombats. This information is required for regulating authorities, and subsequently wildlife carers, and managers, to make fully informed decisions about wombat sarcoptic mange treatment.
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Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the... more
Ticks (Arachnida: Acari) are vectors for pathogens and the biggest threat to animal health. Many Australian ticks are associated with pathogens that impact humans, domestic animals and livestock. However, little is known about the presence or impact of tick-borne pathogens in native Australian wildlife. Wombats are particularly susceptible to the effects of the ectoparasite Sarcoptes scabiei which causes sarcoptic mange, the reason for which is unknown. Factors such as other ectoparasites and their associated pathogens may play a role. A critical understanding of the species of ectoparasites that parasitise wombats and their pathogens, and particularly ticks, is therefore warranted. This review describes the ectoparasites of wombats, pathogens known to be associated with those ectoparasites, and related literature gaps. Pathogens have been isolated in most tick species that typically feed on wombats; however, there are minimal molecular studies to determine the presence of pathogens in any other wombat ectoparasites. The development of next-generation sequencing (NGS) technologies allows us to explore entire microbial communities in ectoparasite samples, allowing fast and accurate identification of potential pathogens in many samples at once. These new techniques have highlighted the diversity and uniqueness of native ticks and their microbiomes, including pathogens of potential medical and veterinary importance. An increased understanding of all ectoparasites that parasitise wombats, and their associated pathogens, requires further investigation.
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There are many limitations when using traditional laboratory species. Limits on variation, may result in limited outcomes, at both the species and individual level, due to different individuals/species having diverse physiological... more
There are many limitations when using traditional laboratory species. Limits on variation, may result in limited outcomes, at both the species and individual level, due to different individuals/species having diverse physiological processes, or differing molecular and genetic mechanisms. By using a variety of model species, we will be able to develop creative solutions to biological problems and identify differences of which we were not previously aware. The laboratory mouse has been a suitable model species for various mammalian studies, however most are bred specifically for laboratory research with limited variability due to selective breeding. Marsupial models offer unique research opportunities compared to eutherian models. We believe that there should be an expansion in marsupial model species, and the introduction of the red-tailed phascogale (Phascogale calura), a dasyurid marsupial, should be one of them. Phascogales are easily managed in captivity, and there are now multiple studies involving their development, reproduction, nutrition, behavior and immune system, which can serve as a baseline for future studies. The addition of the phascogale as a model species will improve future mammalian studies by introducing variability and offer alternate solutions to biological problems, particularly in the areas of genetics, nutrition, immunology, the neuro-endocrine system, and ageing, due to their semelparous reproductive strategy and hence, subsequent predictive physiology. In this review, we provide information based on existing research on red-tailed phascogales to support their inclusion as a model species. K E Y W O R D S ageing, dasyurid, laboratory model, model species, Phascogale calura, stress
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Comparative Immunology Consortium 2 T he common origin of all species provides a wealth of history recorded in DNA and a lens for understanding human biology. Immunology research has traditionally used rodents as the model of choice.... more
Comparative Immunology Consortium 2 T he common origin of all species provides a wealth of history recorded in DNA and a lens for understanding human biology. Immunology research has traditionally used rodents as the model of choice. However, transla-tional success has not met its full potential. Broadening immunology research to integrate comparative approaches across species and environments can amplify the potential of immunology to improve the lives of humans and other animals. Additionally, it can lead to discoveries that are not possible in a restricted set of model organisms and environments. For example, the contemporary vaccine era arose from observing human-animal interactions in a real-world environment (cowpox infection protected milkmaids from smallpox). Most emerging infectious diseases (EIDs) originate in domestic and wild animals (1), and the coronavirus disease 2019 (COVID-19) pandemic is a stark reminder of the need to think more holistically about the health of humans and animals. The architecture of the immune system is an intricate network that has evolved over millions of years. Although no model organism can replicate all aspects of health and disease in another species, comparison of DNA and protein sequences across the tree of life is a straightforward and cost-effective means to select the most appropriate animal models for the question at hand (see the figure). For example, the current era of cancer immu-notherapy was ushered in by the success of therapies that targeted the immune checkpoint protein cytotoxic T lymphocyte-associated protein 4 (CTLA4). Of the 134 mammals and 76 birds with CTLA4 orthologs listed in the National Center for Biotechnology Information Gene database, the key ligand binding motif (Met-Tyr-Pro-Pro-Pro-Tyr) in CTLA4 is identical in all 76 bird species and 131 of 134 mammals. Pigs (Sus scrofa) are common large-animal models for human pa-thologies and xenografts (implantation of tissue from another species), but they are one of the three species that have a divergent ligand-binding motif in CTLA4 (2). Accounting for differences in key immunoregulatory genes among experimental species can be easily integrated into the experimental design stage of the research process. The lack of reagents, such as monoclonal antibodies, for most species has historically been a barrier to integrating new species into the biomedical research cycle. However, the increasing number of fully sequenced genomes allows rapid comparison of gene networks across more than 200 species. De novo transcriptome assemblies can provide transcript sequences and expression patterns of species for which full genome sequence databases are unavailable, so that recombinant proteins can be quickly produced for protein-based immunology in species of interest (3). Funding constraints that limit development of specific reagents for every species can be overcome through a systematic effort to develop and characterize antibodies, nano-bodies, or aptamers that bind to conserved protein motifs across taxonomic orders. This can reduce the number of reagents that need to be developed and enhance research efficiency by reducing the need for individual laboratories to sift out cross-reactive reagents for their species of interest. For example, antibodies that bind the conserved regions of proteins (such as CTLA4 ligand-binding motif) could potentially be used for immu-nophenotyping and functional assays in most vertebrate species. Standardized reagent panels that can be used for serological assays of immunoglobulins [such as immunoglobulin A (IgA), IgE, IgG, and IgM] and can identify key cell types (such as resident memory T cells) will allow meaningful comparison across species and larger taxonomic groups. The reagent development process itself has been simplified by the astute but serendipi-tous discovery of heavy chain-only antibodies in camels (Camelus dromedarius) (4). This IMMUNOLOGY Rewilding immunology Integrating comparative immunology can improve human, animal, and ecosystem health Comparative phylogenetic analysis Identify the right models Dirty mouse models Improve translation and discovery Real-world immunology Identify the problems and solutions Conservation Discovery Emerging infectious disease research Real-world immunology feedback cycle Expanding the breadth of immunology to include more species and environments could benefit biomedical research. Phylogenetic analysis identifies appropriate model species. Successful laboratory mouse experiments replicated in "dirty" mice or natural disease models can stimulate a dynamic feedback cycle that improves preparedness for emerging infectious diseases, conservation efforts, and discovery of compounds that are not present in a restricted set of model species.
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Wombats are large marsupial grazers native to Australia. They are 'ecosystem engineers' due to their burrowing, impacting rates of soil turnover, assisting with nutrient cycling and water infiltration, and creating habitat for other... more
Wombats are large marsupial grazers native to Australia. They are 'ecosystem engineers' due to their burrowing, impacting rates of soil turnover, assisting with nutrient cycling and water infiltration, and creating habitat for other species. The aim of this review is to provide an overview of available information on the habitat and distribution, abundance and threats to bare-nosed wombats (Vombatus ursinus), and to provide a critical review of the current gaps in our knowledge to aid future management of the species. Bare-nosed wombats were previously widespread. Since European settlement their range has reduced. While habitat loss and contraction impact population numbers, bare-nosed wombat populations are also threatened by roadkill, introduced species, legal and illegal human persecution, and disease. Further research is required to understand the historic range of bare-nosed wombats, as well as current population numbers, so that we can determine the threats that most significantly impact this species. Increasing our understanding of habitat requirements, distribution and population numbers, as well as how to mitigate threats, will aid future management and conservation strategies for the species.
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Marsupials and eutherians are mammals that differ in their physiological traits, predominately their reproductive and developmental strategies; eutherians give birth to well-developed young, while marsupials are born highly altricial... more
Marsupials and eutherians are mammals that differ in their physiological traits, predominately their reproductive and developmental strategies; eutherians give birth to well-developed young, while marsupials are born highly altricial after a much shorter gestation. These developmental traits also result in differences in the development of the immune system of eutherian and marsupial species. In eutherians, B-cells are the key to humoral immunity as they are found in multiple lymphoid organs and have the unique ability to mediate the production of antigen-specific antibodies in the presence of extracellular pathogens. The development of B-cells in marsupials has been reported and hypothesised to be similar to that of eutherians, except that haematopoiesis occurs in the liver, postpartum, until the bone marrow fully matures. In eutherians, specific genes are linked to specific stages in B-cell development, maturation, and differentiation processes, and have been identified including immunoglobulins (heavy and light chains), cluster of differentiation markers (CD10, 19, 34 and CD79α/ β), signal transduction molecules (BTK, Lyn and Syk) and transcriptional regulators (EBF1, E2A, and Pax5). This review aims to discuss the known similarities and differences between marsupial and eutherian B-cells, in regards to their genetic presence, homology, and developmental stages, as well as to highlight the areas requiring further investigation. By enhancing our understanding of the genes that are involved with B-cells in the mar-supial lineage, it will, in turn, aid our understanding of the marsupial immune system and support the development of specific immunological reagents for research and wildlife conservation purposes.
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Studies of gene diversity are used to investigate population dynamics, including immunological fitness. Aside from the selection of an appropriate gene target, an important factor that underpins these studies is the ability to recover... more
Studies of gene diversity are used to investigate population dynamics, including immunological fitness. Aside from the selection of an appropriate gene target, an important factor that underpins these studies is the ability to recover viable DNA samples from native animals that are protected, threatened or difficult to sample or locate such as the bare-nosed wombat (Vombatus ursinus). In this study, we used genomic DNA extracted from muscle tissue samples and also identified the optimal method to extract DNA from fresh wombat scat samples to enable further analyses to be performed using non-invasive techniques. The DNA was probed via the polymerase chain reaction using previously targeted marsupial Major Histocompatibility Complex (MHC) gene primers. These genes are highly variable and associated with binding and presentation of pathogens in the immune system. Twenty-three unique MHC Class II DAB V. ursinus gene sequences were translated to 21 unique predicted peptide sequences from 34 individual tissue or scat samples. Vombatus ursinus MHC Class II DAB gene and peptide sequences were most similar to other marsupial DNA and peptide sequences. Further analysis also indicated the likelihood of MHC Class II DAB family membership through motif identification. Additional sampling is required to assess the full level of diversity of MHC Class II DAB genes among V. ursinus populations; however, this study is the first to identify MHC genes in a wombat and will advance immunological and disease studies of the species.
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Objectives: The genetic diversity of an eastern grey kangaroo (Macropus giganteus) population surrounded by land‑ scape barriers was examined. DNA was extracted from tissue samples from 22 road‑killed kangaroos, and blood sam‑ ples from... more
Objectives: The genetic diversity of an eastern grey kangaroo (Macropus giganteus) population surrounded by land‑ scape barriers was examined. DNA was extracted from tissue samples from 22 road‑killed kangaroos, and blood sam‑ ples from four live captured kangaroos. Amplified loci were used to determine relatedness between individual kanga‑ roos. The level of relatedness and location of road‑killed kangaroos were compared to evaluate spatial autocorrelation. Results: The expected and observed heterozygosity confirmed the loci were polymorphic and highly informative for use in this population. One pair of kangaroos were identified to be full siblings, and a high proportion were identified as half siblings. Six positive parentage assignments were detected. No correlation between relatedness and crossing site was detected.
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Background: The red-tailed phascogale is a 'Near Threatened' dasyurid marsupial. Males are semelparous and die off shortly after the breeding season in the wild due to a stress-related syndrome, which has many physiological and... more
Background: The red-tailed phascogale is a 'Near Threatened' dasyurid marsupial. Males are semelparous and die off shortly after the breeding season in the wild due to a stress-related syndrome, which has many physiological and immunological repercussions. In captivity, males survive for more than 2 years but become infertile after their first breeding season. Meanwhile, females can breed for many years. This suggests that captive males develop similar endocrine changes as their wild counterparts and undergo accelerated aging. However, this remains to be confirmed. The health status and immune function of this species in captivity have also yet to be characterized. Results: Through an integrative approach combining post-mortem examinations, blood biochemical and hematological analyses, we investigated the physiological and health status of captive phascogales before, during, and after the breeding season. Adult males showed only mild lesions compatible with an endocrine disorder. Both sexes globally maintained a good body condition throughout their lives, most likely due to a high quality diet. However, biochemistry changes potentially compatible with an early onset of renal or hepatic insufficiency were detected in older individuals. Masses and possible hypocalcemia were observed anecdotally in old females. With this increased knowledge of the physiological status of captive phascogales, interpretation of their immune profile at different age stages was then attempted. During the breeding season, males developed a stress leukogram characterized by a marked lymphopenia, further aggravated by a severe leukopenia after the breeding season. To determine whether these changes were limited to the peripheral blood or had more profound implications, histopathology of the spleen was performed opportunistically. Adult males showed white pulp atrophy, at various degrees. The atrophy was mainly lymphoid and more severe in 1.5-year-old males than in 3.5-year-old females. These results suggest that captive males undergo accelerated immunosenescence.
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Objective: Marsupials suffer from an increasing number of stressors in this changing world. Functional studies are thus needed to broaden our understanding of the marsupial immune system. The red-tailed phascogale (Phascogale calura) is a... more
Objective: Marsupials suffer from an increasing number of stressors in this changing world. Functional studies are thus needed to broaden our understanding of the marsupial immune system. The red-tailed phascogale (Phascogale calura) is a small Australian marsupial previously used in descriptive immunological studies. Here, we aimed to develop functional assays by isolating and stimulating blood and spleen mononuclear cells in vitro. Results: While peripheral blood mononuclear cell (PBMC) were relatively easy to isolate, only 10 5 mononuclear cells (> 90% purity and > 75% viability) could be recovered from the spleen, independently of the sex and age of the animal or the centrifugation time and speed tested. The pores of the mesh sieve used for tissue homogenization might have been too big to yield a single cell suspension. Nevertheless, in spite of the overall low number of cells recovered, PBMC and splenic mononuclear cells were successfully activated in preliminary trials with phytohemaglutinin. This activation state was evidenced by a change in shape and the presence of small cell aggregations in the mitogen-stimulated cultures. A non-radioactive colorimetric assay was also performed to confirm cell proliferation in these wells. This work highlights the importance of developing and reporting detailed methodological protocols in non-traditional research species.
Research Interests: Immunology, Stress, Mammalogy, Marsupials, Mammals, and 5 moreComparative Immunology, Blood, Dasyurids, PBMC, and semelparous
A B S T R A C T Expressed coding sequences were identified for the T cell receptors TCRα, TCRβ, TCRγ, TCRδ, TCRμ, and co-receptors CD3ε, CD4, and CD8α in the red-tailed phascogale (Phascogale calura). Expression of these genes was... more
A B S T R A C T Expressed coding sequences were identified for the T cell receptors TCRα, TCRβ, TCRγ, TCRδ, TCRμ, and co-receptors CD3ε, CD4, and CD8α in the red-tailed phascogale (Phascogale calura). Expression of these genes was examined in the developing thymus and spleen of pouch young and juvenile individuals to detect any changes in expressionrelative to developmental stages. Transcripts of CD3ε, CD4, TCRδ and TCRμ were first detected in the thorax at 1 day postpartum (dpp), and transcripts of all target genes were detected in the thymus from 3 dpp, and the spleen from 17 dpp. The relative expression of all target genes changed significantly over the course of pouch life and was associated with histological milestones of both the thymus and the spleen. Peak gene expression was observed early in pouch life in the thymus, with a decrease in expression associated with timing of thymic involution, while expression peaked later in the spleen and was associated with the initial differentiation of the red and white pulp and a population of T cells forming the periarterial lymphatic sheath (PALS). Active expression of these target genes within the thymus and spleen indicates that the young marsupials are actively developing immunocompetence during pouch life.
Spinifex hopping-mice (Notomys alexis) and plains mice (Pseudomys australis) are able to successfully occupy arid zones of Australia. We studied the digestive parameters and energy assimilation of captive spinifex hopping-mice and plains... more
Spinifex hopping-mice (Notomys alexis) and plains mice (Pseudomys australis) are able to successfully occupy arid zones of Australia. We studied the digestive parameters and energy assimilation of captive spinifex hopping-mice and plains mice. The experiment consisted of six diets fed to the animals for periods of 12 days per food type. On a dry matter basis, the plains mice consumed between 2.5 and 7.2% and the hopping-mice between 5.8 and 9.3% of their body mass in food per day. The body mass of the spinifex hopping-mice increased significantly on the sunflower seed diet, while body mass did not change significantly for the plains mice on any diet. Apparent digestibility of macronutrients was similar in the hopping-mice and plains mice when maintained on the same diet, however digestibility of total micronutrients differed. Maintenance energy requirements for the plains mice were 529 kJ kg −0.75 d −1 and spinifex hopping-mice 550 kJ kg −0.75 d −1. Spinifex hopping-mice and plains mice are able to exploit a range of food items and efficiently digest macronutrients, to ensure they meet their nutritional needs, an ability they require in the variable arid environment. The information gained in this study increases the paucity of information on Australian native murids, specifically their digestive function and energy requirements, and will aid captive murid management. The study will allow future expansion into field studies, to aid the conservation of wild rodent diets and nutrition of arid zone murids.
Camera traps are frequently used in wildlife research and may be a useful tool for monitoring behavioural patterns. The suitability of camera traps to monitor behaviour depends on the size, locomotion, and behaviour of the species being... more
Camera traps are frequently used in wildlife research and may be a useful tool for monitoring behavioural patterns. The suitability of camera traps to monitor behaviour depends on the size, locomotion, and behaviour of the species being investigated. The suitability of cameras for documenting the behaviour of eastern grey kangaroos was assessed here by comparing activity patterns collected using cameras to published activity patterns for the species. The activity patterns calculated from camera trap data were largely consistent with data from previous studies, although nocturnal activity appeared to be under-represented. Observations of unusual fighting behaviour illustrates the potential for camera traps to enable capture of novel observations. Kangaroo behaviour appeared to be influenced by the presence of cameras; however, no kangaroos retreated from cameras. Data suggested that kangaroos became habituated to cameras after eight months. The findings of this study suggest that camera traps are suitable for assessing the diurnal activity of eastern grey kangaroos and are useful tools for documenting their behaviour.
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Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific... more
Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific complement proteins remains largely unexplored. We report partial cDNA sequences for two complement-activating proteins, C3, C1r, CFP and MASP2, in liver tissues from red-tailed phascogale (Phascogale calura). Conservation of functionally relevant motifs were identified in the translated cDNA sequences from phascogale C3, CFP and MASP2 and their eutherian homologues. Gene expression of representative molecules from each of the major complement pathways was also investigated in whole body tissues from 1 to 18 day old animals and liver tissues from 31-day to 14-month old animals. Average complement expression in whole bodies and liver tissues of C1r, CFP, MASP2 and C3 increased significantly in juveniles compared to pouch young, presumably due to the maturation of the young's own complement system. Comparing expression in liver tissues only, we found that the average CFP expression were higher in pouch young compared to juveniles, while results were still statistically similar to the average expression of all tissues for C1r, MASP2 and C3. The average complement expression then significantly decreased as the animals aged into adulthood.
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Baseline haematology, blood chemistry and acute phase protein parameters have not previously been published for free-ranging eastern grey kangaroos (Macropus giganteus). Eight eastern grey kangaroos, including three adult males, three... more
Baseline haematology, blood chemistry and acute phase protein parameters have not previously been published for free-ranging eastern grey kangaroos (Macropus giganteus). Eight eastern grey kangaroos, including three adult males, three adult females and two subadult males from two different populations, were examined. Assays assessed the antibacterial activity of kangaroo serum against one Gram-positive and three Gram-negative bacteria. The kangaroo serum had a strong antibacterial response to Klebsiella pneumoniae, and moderate responses to Escherichia coli and Staphylococcus aureus. The presence and level of acute phase proteins, haptoglobin and serum amyloid A in kangaroos was investigated. Haptoglobin and serum amyloid A were present in kangaroo serum, but only haptoglobin was elevated in a kangaroo with capture myopathy and necrotic wounds. The findings of this study provide preliminary data on health parameters of free-ranging eastern grey kangaroos. These parameters can be used to assist in assessing health in free-ranging populations.
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Research Interests: Immunology, Bacteriology, Antimicrobial Peptides, Innate immunity, Marsupials, and 11 moreAntimicrobials, Comparative Immunology, Blood, Antimicrobial activity, Veterinary Microbiology especially bacteriology, immunology and Virology, Marsupialia, Immunohaematology/pathogenic Bacteriology, Immunohaematology, Marsupial Immunology, Marsupiales, and Australian Marsupials
Research Interests: Parasitology, Herpetology, Wildlife Ecology And Management, Python, Wildlife Conservation, and 12 moreWildlife Diseases, Ticks, Veterinary Parasitology, Parasites, Wildlife, Snakes, Tick-Borne Pathogens, Ectoparasites, Snake, Herpetology and conservation, Ticks and Tick Borne Diseases, and Animal Parasites
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Background. Reference genes serve an important role as an endogenous control/s-tandard for data normalisation in gene expression studies. Although reference genes have recently been suggested for marsupials, independent analysis of... more
Background. Reference genes serve an important role as an endogenous control/s-tandard for data normalisation in gene expression studies. Although reference genes have recently been suggested for marsupials, independent analysis of reference genes on different immune tissues is yet to be tested. Therefore, an assessment of reference genes is needed for the selection of stable, expressed genes across different marsupial tissues. Methods. The study was conducted on red-tailed phascogales (Phascogale calura) using five juvenile and five adult males. The stability of five reference genes (glyceraldehyde-3-phosphate dehydrogenase, GAPDH ; β-actin, ACTB; 18S rRNA, 18S; 28S rRNA, 28S; and ribosomal protein L13A, RPL13A) was investigated using SYBR Green and analysed with the geNorm application available in qBase PLUS software. Results. Gene stability for juvenile and adult tissue samples combined show that GAPDH was most stable in liver and lung tissue, and 18S in small intestine and spleen. While all reference genes were suitable for small intestine and spleen tissues, all reference genes except 28S were stable for lung and only 18S and 28S were stable for liver tissue. Separating the two age groups, we found that two different reference genes were considered stable in juveniles (ACTB and GAPDH) and adults (18S and 28S), and RPL13A was not stable for juvenile small intestine tissue. Except for 28S, all reference genes were stable in juvenile and adult lungs, and all five reference genes were stable in spleen tissue. Discussion. Based on expression stability, ACTB and GAPDH are suitable for all tissues when studying the expression of marsupials in two age groups, except for adult liver tissues. The expression stability between juvenile and adult liver tissue was most unstable, as the stable reference genes for juveniles and adults were different. Juvenile and adult lung, small intestine and spleen share similar stable reference genes, except for small intestine tissues where all reference genes were stable in adults but RPL13A was not suitable in juveniles.
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Interleukin-10 is an immunomodulatory cytokine that has been implicated, along with IFN-c, in the disease sequelae of mycobacterial infection. In order to investigate the role of IL-10 in marsupial disease models we sequenced and... more
Interleukin-10 is an immunomodulatory cytokine that has been implicated, along with IFN-c, in the disease sequelae of mycobacterial infection. In order to investigate the role of IL-10 in marsupial disease models we sequenced and characterised the IL10 gene in the tammar wallaby (Macropus eugenii) and rufous hare-wallaby (Lagorchestes hirsutus). An isoform IL-10D3, in which an in-frame deletion of exon 3 occurs, was discovered in both macropod species. Analysis of wallaby and other reported marsupial IL-10 homologs suggests that while marsupial IL-10 is comparable to that of human IL-10, the predicted IL-10D3 protein may play a more complicated role in the modulation of IL-10-directed responses. Expression of the canonical gene and splicing variant was confirmed in both wallabies, and the rufous hare-wallaby showed differential expression across lymph node, spleen and liver, with isoform expression detected in the lymph node. This characterisation and expression of IL-10 in de novo tissues provides a basis for further study into the role of IL-10 in disease models in marsupials.
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Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific... more
Marsupials are born immunologically premature, relying on cells and molecules in maternal milk for immune protection. Both immunoglobulin and complement proteins have been identified in marsupial milk, but the expression of specific complement proteins remains largely unexplored. We report partial cDNA sequences for two complement-activating proteins, C3, C1r, CFP and MASP2, in liver tissues from red-tailed phascogale (Phascogale calura). Conservation of functionally relevant motifs were identified in the translated cDNA sequences from phascogale C3, CFP and MASP2 and their eutherian homologues. Gene expression of representative molecules from each of the major complement pathways was also investigated in whole body tissues from 1 to 18 day old animals and liver tissues from 31-day to 14-month old animals. Average complement expression in whole bodies and liver tissues of C1r, CFP, MASP2 and C3 increased significantly in juveniles compared to pouch young, presumably due to the maturation of the young's own complement system. Comparing expression in liver tissues only, we found that the average CFP expression were higher in pouch young compared to juveniles, while results were still statistically similar to the average expression of all tissues for C1r, MASP2 and C3. The average complement expression then significantly decreased as the animals aged into adulthood.
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The black-footed tree-rat (Mesembriomys gouldii) and greater stick-nest rat (Leporillus conditor) are near threatened and vulnerable native Australian murids. There is a paucity of health and welfare knowledge for these species and native... more
The black-footed tree-rat (Mesembriomys gouldii) and greater stick-nest rat (Leporillus conditor) are near threatened and vulnerable native Australian murids. There is a paucity of health and welfare knowledge for these species and native murids in general. In this paper we aimed to address this deficiency in knowledge by describing some key haematological and blood biochemistry parameters for these species. Haematology
and blood biochemistry data were obtained from clinical histories of the two murid species held in captivity at Taronga Zoological Park, Mosman, Australia. The data were analysed to establish confidence intervals for each parameter available and leukocyte morphology described. White blood cell counts were higher in females than males.
Both species also had high neutrophil:lymphocyte ratios (tree-rat ratios were almost even). Haematocrit was higher in male stick-nest rats than females. Differential leukocyte
counts and leukocyte morphology was consistent with previous descriptions in other murids and between individuals. Blood biochemistry values were unremarkable
except for the high level of globulin in stick-nest rats. The values provided in the study will add to the knowledge of health data for murids in captivity and aid captive and
natural management of Australian native murids.
and blood biochemistry data were obtained from clinical histories of the two murid species held in captivity at Taronga Zoological Park, Mosman, Australia. The data were analysed to establish confidence intervals for each parameter available and leukocyte morphology described. White blood cell counts were higher in females than males.
Both species also had high neutrophil:lymphocyte ratios (tree-rat ratios were almost even). Haematocrit was higher in male stick-nest rats than females. Differential leukocyte
counts and leukocyte morphology was consistent with previous descriptions in other murids and between individuals. Blood biochemistry values were unremarkable
except for the high level of globulin in stick-nest rats. The values provided in the study will add to the knowledge of health data for murids in captivity and aid captive and
natural management of Australian native murids.
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Expressed coding sequences for interleukin-6 (IL-6) and interleukin-6 receptor a (IL-6R) were examined in five marsupial species. Full length expressed coding sequences for IL-6 and IL-6R were identified and characterized in the gray... more
Expressed coding sequences for interleukin-6 (IL-6) and interleukin-6 receptor a (IL-6R) were examined in five marsupial species. Full length expressed coding sequences for IL-6 and IL-6R were identified and characterized in the gray short-tailed opossum (Monodelphis domestica). For IL-6, ~225 bp fragments of the mRNA sequence were identified in the red-tailed phascogale (Phascogale calura), kultarr (Ante-chinomys laniger), and stripe-faced dunnart (Sminthopsis macroura), while ~563 bp fragments of mRNA encoding IL-6R were identified in the red-tailed phascogale, kultarr, stripe-face dunnart and fat-tailed dunnart (Sminthopsis crassicaudata). Relative expression levels of IL-6 and IL-6R were examined in the heart, muscle, lung, liver, spleen and kidney of adult red-tailed phascogales, and IL-6 gene expression was found to be significantly higher in the lung and spleen than the other tissues examined, while the expression of IL-6R was significantly higher in the liver, lung and spleen. These results now serve as a reference point for examining the role and levels of IL-6 and IL-6R in the health and disease of these marsupial species. The pro-tumorigenic nature of IL-6 is of particular interest, and the identification of these IL-6 and IL-6R coding sequences provides a platform for further work to evaluate the potential role of IL-6 in marsupial cancers.
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In mammals, interleukin-21 is a member of the common gamma chain cytokine family that also includes IL-2, IL-4, IL-7, IL-9 and IL-15. IL-21 has pleiotropic effects on both myeloid and lymphoid immune cells and as a consequence, the... more
In mammals, interleukin-21 is a member of the common gamma chain cytokine family that also includes IL-2, IL-4, IL-7, IL-9 and IL-15. IL-21 has pleiotropic effects on both myeloid and lymphoid immune cells and as a consequence, the biological actions of IL-21 are broad: regulating both innate and adaptive immune responses and playing a pivotal role in antivi-ral, inflammatory and antitumour cellular responses. While IL-21 genes have been characterized in mammals , birds, fish and amphibians, there are no reports for any marsupial species to date. We characterized the expressed IL-21 gene from immune tissues of two macropod species, the tammar wallaby (Macropus eugenii), a model macropod, and the closely related endangered bridled nailtail wallaby (Onychogalea fraenata). The open reading frame of macropod IL-21 is 462 nucleotides in length and encodes a 153-mer putative protein that has 46% identity with human IL-21. Despite the somewhat low amino acid conservation with other mammals, structural elements and residues essential for IL-21 conformation and receptor association were conserved in the macropod IL-21 predicted peptides. The detection of IL-21 gene expression in T-cell-enriched tissues, combined with analysis of the promotor region of the tammar wallaby gene, suggests that macropod IL-21 is expressed in stimulated T cells but is not readily detected in other cells and tissues. The similarity of gene expression profile and functionally important amino acid residues to eutherian IL-21 makes it unlikely that the differences in Band T-cell responses that are reported for some marsupial species are due to a lack of important functional residues or IL-21 gene expression in this group of mammals.
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The thylacine (Thylacinus cynocephalus) was Australia's largest marsupial carnivore until its extinction within the last century. There remains considerable interest and debate regarding the biology of this species. Studies of thylacine... more
The thylacine (Thylacinus cynocephalus) was Australia's largest marsupial carnivore until its extinction within the last century. There remains considerable interest and debate regarding the biology of this species. Studies of thylacine biology are now limited to preserved specimens, and parts thereof, as well as written historical accounts of its biology. This study describes the development of the immune tissues of a pouch young thylacine, one of only eleven in existence, and the only specimen to be histologically sectioned. The appearance of the immune tissue of the developing pouch young thylacine is compared to the immune tissues of extant marsupials, providing insights into the immunity, biology and ecology of the extinct thylacine.
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Diversity in major histocompatibility complex (MHC) genes can be correlated with the level of immunological fitness of an individual or group of individuals. This study tested published primer sets designed to amplify fragments of the MHC... more
Diversity in major histocompatibility complex (MHC) genes can be correlated with the level of immunological fitness of an individual or group of individuals. This study tested published primer sets designed to amplify fragments of the MHC Class II DAB and DBB genes to amplify the equivalent gene fragments in red-tailed phascogales (Phascogale calura). Seventeen genomic DNA samples extracted from phascogale muscle tissue were used to amplify the initial DAB and DBB fragments; however, only DAB PCR proved successful. The fragments were 172 bp in length between the primers and had a high level of identity to other known marsupial MHC Class II DAB gene sequences (89–98%), including those of the koala (Phascolarctos cinereus), Tasmanian devil (Sarcophilus harrisii), common brushtail possum (Trichosurus vulpecula) and several wallaby species. Multiple sequence alignment revealed limited variability of MHC Class II genes between the individuals, but eight individual sequences in total. Genomic DNA was subsequently extracted from three fresh red-tailed phascogale scat samples and DAB fragments successfully amplified. The technique will allow for red-tailed phascogales to be sampled non-invasively in the wild and to determine the level of MHC diversity among individuals in the population.
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Marsupials are a group of mammals that give birth to immature young lacking mature immune tissues at birth, and are unable to mount their own specific immune defence. Their immune tissues develop in a non-sterile ex-utero environment... more
Marsupials are a group of mammals that give birth to immature young lacking mature immune tissues at birth, and are unable to mount their own specific immune defence. Their immune tissues develop in a non-sterile ex-utero environment unlike that of eutherian mammals such as ourselves. Marsupials are therefore ideal models for studying the development of immune tissues, in particular haematopoiesis, yet relatively little has been investigated. Most studies have been restricted to histological or immu-nohistological studies, however some factors likely to be involved, based on eutherian studies in hae-matopoiesis, have been isolated and characterised, including a few key markers, and some cell signaling and regulation molecules, mostly involved in lymphocytopoiesis. However the role of many molecules in haematopoiesis is largely presumed. We currently lack much of the rudimentary information regarding time of appearance and expression levels of these molecules, and no functional studies have been conducted. This paper reviews our knowledge of marsupial haematopoiesis to date, and highlights the need for future research in marsupials to gain further insights into the evolution of haematopoiesis.
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The complement system is a major mediator of the vertebrate immune system, which functions in both innate and specific immune responses. It comprises more than 30 proteins working to remove foreign cells by way of anaphylatoxins, opsonins... more
The complement system is a major mediator of the vertebrate immune system, which functions in both innate and specific immune responses. It comprises more than 30 proteins working to remove foreign cells by way of anaphylatoxins, opsonins or the membrane attack complex. Over the last few years, whole genome sequences of non-eutherian mammals (marsupials and a monotreme), the gray short-tailed opossum (Monodelphis domestica), tammar wallaby (Macropus eugenii), Tasmanian devil (Sarcophilus harrisii), koala (Phascolarctos cinereus) and platypus (Ornithorhynchus anatinus), have become publicly available. Using these sequences, we have identified an array of complement components in non-eutherians using online search tools and algorithms. Of 57 complement and complement-related genes investigated, we identified 46 in the gray short-tailed opossum genome, 27 in the tammar wallaby genome, 44 in the Tasmanian devil genome, 47 in the koala genome and 40 in the platypus genome. The results of this study confirm the presence of key complement components in the immune repertoire of non-eutherian mammals and provide a platform for future studies on immune protection in young marsupials.
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Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail... more
Populations of the common ringtail possum (Pseudocheirus peregrinus) in inland New South Wales have declined or disappeared. Habitat requirements and diet of these populations are poorly understood. Determining the diet of inland ringtail possums is crucial to understanding the factors limiting their survival, and was the focus of this study. Spotlighting surveys were conducted to locate ringtail possums, and scat and vegetation samples were collected for microhistological analysis. Ringtail possums were most frequently observed in red stringybark followed by bundy box and black cypress pine trees, and this correlated with the most common dietary items consumed.
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Generally the reporting of diseases and parasites in Australian native murids is rare despite murids making up ~25% of the native mammal fauna of Australia. This paper reports a malignant melanoma in a captive spinifex hopping-mouse... more
Generally the reporting of diseases and parasites in Australian native murids is rare despite murids making up ~25% of the native mammal fauna of Australia. This paper reports a malignant melanoma in a captive spinifex hopping-mouse (Notomys alexis) and is the first case of melanoma reported in any native Australian murid. With no exposure to ultraviolet radiation the melanoma is proposed to be the result of genetic predisposition and age. As no other reports have been observed in the colony it is likely to be a very rare event in captivity and unlikely to occur in the wild.
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Torpor is an important physiological process used to reduce body temperature and thus energy needs in mammals and birds. Rewarming from torpor can be costly. In some small mammals basking is used to reduce the cost of rewarming from... more
Torpor is an important physiological process used to reduce body temperature and thus energy needs in
mammals and birds. Rewarming from torpor can be costly. In some small mammals basking is used to
reduce the cost of rewarming from torpor. The use and duration of basking was measured in two native
Australian marsupials, the red-tailed phascogale (Phascogale calura) and kultarr (Antechinomys laniger),
using a heat rock. Animals were observed via video cameras to determine whether they used basking
behaviours and whether this behaviour was affected by food availability. Both species became accustomed
to the heat rock as time progressed. Absence of food increased basking duration and frequency
in some individuals but not all animals. Generally kultarrs basked for longer periods than phascogales,
and kultarrs would bask at all hours of the day while phascogales showed a strict nocturnal regime
(1900–0700 h). The results demonstrate that basking may be an important behavioural adaptation of the
kultarr; while the phascogale requires further research.
mammals and birds. Rewarming from torpor can be costly. In some small mammals basking is used to
reduce the cost of rewarming from torpor. The use and duration of basking was measured in two native
Australian marsupials, the red-tailed phascogale (Phascogale calura) and kultarr (Antechinomys laniger),
using a heat rock. Animals were observed via video cameras to determine whether they used basking
behaviours and whether this behaviour was affected by food availability. Both species became accustomed
to the heat rock as time progressed. Absence of food increased basking duration and frequency
in some individuals but not all animals. Generally kultarrs basked for longer periods than phascogales,
and kultarrs would bask at all hours of the day while phascogales showed a strict nocturnal regime
(1900–0700 h). The results demonstrate that basking may be an important behavioural adaptation of the
kultarr; while the phascogale requires further research.
Research Interests: Marsupials and Torpor
Red-tailed phascogale (Phascogale calura) pouch young at birth were relatively underdeveloped in comparison with their eutherian counterparts, and the lymphoid tissues of the immune system were found to be histologi-cally immature. The... more
Red-tailed phascogale (Phascogale calura) pouch young at birth were relatively underdeveloped in comparison with their eutherian counterparts, and the lymphoid tissues of the immune system were found to be histologi-cally immature. The phascogale thymus rapidly developed in the first few days of pouch life and was quickly populated with lymphocytes. By the end of pouch life, involution of the thymus was underway. The bone marrow started to develop in the early stage of pouch life, although adipocytes and megakaryocytes were not observed until slightly later. The liver was hematopoietic from birth and reached histological maturity toward the end of pouch life. The lymph nodes were difficult to detect macroscopically because of their small size, but were easily identified microscopically later in pouch life, particularly in the mesentery, and these lymph nodes exhibited germinal centers by the end of pouch life. The early spleen was pre-dominately mesenchymal, but exhibited some erythropoiesis. Follicles with well-developed germinal centers were not observed until the latest stage of pouch life. Although intraepithelial lymphocytes were detected in the intestines early in pouch life, the discrete lymphoid aggregates and Peyer's patches characteristic of the gut-associated lymphoid tissue (GALT) were not detected until later in pouch life. This is the first report of histological development in phascogale pouch young, as well as the first report of the thymus, bone marrow, and lymph nodes in this dasyurid species at any age. Anat Rec, 299:207–219, 2016. V C 2015 Wiley Periodicals, Inc.
Research Interests: Histology, Marsupials, Spleen, Liver, Bone marrow, and 3 moreThymus, Marsupial Immunology, and Lungs
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Research Interests: Physiology, Zoology, Morphology, Spleen, Humans, and 7 moreLiver, Adaptive Immunity, Animals, Bone marrow, Skin, Marsupialia, and Lymphoid Tissue
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Red-tailed phascogales Phascogales calura are near-threatened (Friend, 2008) arboreal Dasyurids. A breeding programme was established at Alice Springs Desert Park in 2001 to aid species recovery. Twenty-five captive-bred phascogales were... more
Red-tailed phascogales Phascogales calura are near-threatened (Friend, 2008) arboreal Dasyurids. A breeding programme was established at Alice Springs Desert Park in 2001 to aid species recovery. Twenty-five captive-bred phascogales were released into a suitable habitat at the park in 2006. If shown to be successful, the initial release was to be expanded with the release of further captive-bred phascogales into a suitable habitat in the nearby National Park and into South Australia. In this study, a dietary analysis was conducted to determine the preferred diet of the translocated phascogales in the park environment. Scats were collected during July–October, 2006 and January–March, 2007 from nesting sites within the park. Faecal samples were weighed, soaked in hot water and particles were separated through sieves before examination under a microscope. Scat analysis methods identified that red-tailed phascogales were primarily insectivorous with 92.6% of all scats containing arthropods. They are also opportunistic predators within the park, consuming birds (51.6%), small mammals (33.3%) and on occasion reptiles, and plant material (27.4%). Seasonal comparison of data through SIMPER analyses showed there was significant variation (P=0.009) between spring and summer, due to a large portion of birds present in the diet in spring. The red-tailed phascogale is able to exploit a number of prey types and it is therefore likely that they would survive a ‘hard’ translocation into the wild provided the site chosen has adequate food supply.
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Research Interests: Management, Genetics, Pathology, Physiology, Zoology, and 20 morePaleontology, Conservation, Reproduction, Ecology, Morphology, Evolution, Systematics, Marsupials, Anatomy, Growth, Behaviour, Marine, Scientific, Educational, Bat, Energetics, Anatomy and Histology, PEST, Digestive physiology, and Survey Techniques
Research Interests: Management, Genetics, Pathology, Physiology, Zoology, and 23 morePaleontology, Immunology, Molecular Biology, Conservation, Reproduction, Ecology, Morphology, Evolution, Systematics, Molecular Genetics, Gene expression, Anatomy, Growth, Behaviour, Marine, Scientific, Educational, Bat, Energetics, PEST, Marsupial ontogeny, Marsupial Immunology, and Survey Techniques
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Research Interests: Zoology, Australia, Ticks, DNA, Phylogeny, and 14 moreParasite, Female, Animals, Male, Bacteria, VECTOR, Marsupialia, Bacterial Diversity, Genotype, Echidna, Native Species, Rickettsia, Hosts, and Phascolarctidae
CD5 has previously been identified in marsupial tissues using anti-human CD5. However, despite the known cross-reactivity of the antibody in marsupial tissues, the cDNA sequence has not previously been characterised in any marsupial. This... more
CD5 has previously been identified in marsupial tissues using anti-human CD5. However, despite the known cross-reactivity of the antibody in marsupial tissues, the cDNA sequence has not previously been characterised in any marsupial. This study has identified the CD5 gene in the opossum genome database and has characterised the CD5 cDNA sequence from the tammar wallaby. Both marsupial CD5 sequences have a high level of sequence identity to known eutherian CD5 sequences, are cysteine-rich and have identical structural motifs to their eutherian homologs. CD5 transcripts were strongly expressed in adult tammar wallaby spleen, mammary node and blood, and expressed at a lower level in liver, kidney and heart tissues. Characterisation of CD5 in marsupials allowed a comparison to the epitope sequence of anti-human CD5 and showed a high level of sequence identity.
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Tasmanian devils are the largest extant marsupial carnivores, confined to the Australian island state of Tasmania. The iconic marsupial has dramatically declined in number since the discovery of devil facial tumor disease in 1996 and... more
Tasmanian devils are the largest extant marsupial carnivores, confined to the Australian island state of Tasmania. The iconic marsupial has dramatically declined in number since the discovery of devil facial tumor disease in 1996 and efforts are being made to uncover vital information to assist in the long-term survival of the species. Ticks are the main vectors of arthropod-borne disease in animals, raising the question of whether Tasmanian devils may be host to arthropods capable of harboring infectious agents. Partially engorged ticks were collected from 35 wild Tasmanian devils and tested for the presence of a range of tick-borne genera. A spotted fever group Rickettsia was detected in 45.5% of samples of the tick Ixodes tasmani (n = 44), from all trapping locations, sharing close sequence identity to members of the Rickettsia massiliae group. A Hepatozoon species was also identified in 34.1% of the same sample set, sharing sequence similarities to Hepatozoon felis, a known pathogen of felids. Dual detection was identified in 13.6% of tick samples, where prevalence of the two genera overlapped. The existence of two previously undetected species of genera known for containing pathogens identifies additional potential risks to the health of the devil population.
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Research Interests: Zoology, Veterinary, Phylogeny, Animals, Antimicrobial Peptide, and 12 moreMacropodidae, Antimicrobial Cationic Peptides, Mammary gland, Gastrointestinal Tract, Veterinary Sciences, Veterinary Immunology, Amino Acid Sequence, Base Sequence, Reverse Transcriptase, Gene Expression Regulation, Innate Immune System, and Molecular Sequence Data
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Research Interests: Genetics, Microbiology, Parasitology, Algorithms, Brazil, and 25 moreChina, Medical Entomology, Veterinary, Ticks, Biological Sciences, Veterinary Parasitology, Phylogeny, Humans, Sheep, DNA Extraction, Animals, Male, Polymerase Chain Reaction, New World, Fisheries Sciences, New South Wales, Chi Square Distribution, Veterinary Sciences, Amino Acid Sequence, Base Sequence, Hedgehogs, Ixodidae, Rickettsia, Phascolarctidae, and Molecular Sequence Data
Research Interests: Immunohistochemistry, Antimicrobials, Antibodies, Cell and Tissue Transplantation, Humans, and 17 moreFemale, Animals, Male, Bone marrow, Medical Physiology, Antimicrobial Peptide, Immune system, Macropodidae, Antimicrobial Cationic Peptides, Epithelium, Gastrointestinal Tract, Age Factors, Species Specificity, Amino Acid Sequence, Epitopes, Biochemistry and cell biology, and Molecular Sequence Data
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Haematology and serum biochemistry was analysed on samples collected from four endangered Carpentarian Rock-rats (Zyzomys palatalis) maintained in a captive colony at the Territory Wildlife Park, Northern Territory. As these animals are... more
Haematology and serum biochemistry was analysed on samples collected from four endangered Carpentarian Rock-rats (Zyzomys palatalis) maintained in a captive colony at the Territory Wildlife Park, Northern Territory. As these animals are endangered, only small sample numbers were able to be analysed. Most haematological and serum biochemical parameters were similar to those for other native Australian murids, with the exception of alkaline phosphatase and creatinine. The study provides preliminary haematology and serum biochemistry information for the Carpentarian Rock-rat and will assist managers of this species to assess the health of the captive and wild populations.
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Changes in the epithelium of the maternal pouch and the mammary gland of brushtail possums (Trichosurus vulpecula) were examined after animals were treated to induce ovulation with follicle-stimulating hormone (FSH), luteinizing hormone... more
Changes in the epithelium of the maternal pouch and the mammary gland of brushtail possums (Trichosurus vulpecula) were examined after animals were treated to induce ovulation with follicle-stimulating hormone (FSH), luteinizing hormone (LH), pregnant mares’ serum gonadotrophin (PMSG) and oestradiol. The mammary glands were similar in appearance to those described in eutherian mammals and in previous studies on other marsupials. Exposure of possums to these compounds, particularly PSMG, appeared to result in changes in the mammary glands that could be associated with milk/secretion production. In contrast, the pouch epithelium had a similar histological appearance to that of epithelium from other parts of the body regardless of whether the animal was exposed to stimulants. These preliminary observations are discussed in the context of the purported role of the pouch epithelium and the mammary gland in production of secretions at oestrus and provision of immunological protection to the neonatal marsupial.
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Haematological and serum biochemical data have been collected from a total of 19 captive-bred Australian native murids (Plains rat, Spinifex hopping-mouse and Central rock-rat). These animals were maintained in a captive population at... more
Haematological and serum biochemical data have been collected from a total of 19 captive-bred Australian native murids (Plains rat, Spinifex hopping-mouse and Central rock-rat). These animals were maintained in a captive population at Alice Springs Desert Park (NT, Australia) and are all central desert inhabitants of Australia. They are currently listed as common, threatened and critically endangered, respectively. Given the status and size of these animals, only small sample numbers and volumes were analysed. The study, however, provides some basic haematology and serum biochemistry information for these three species and will serve as an effective management tool for assessing and monitoring the health status of individuals, particularly those in captivity.
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The development of the liver, bone marrow and spleen have been investigated in the stripe-faced dunnart. At birth, the liver was undergoing haematopoiesis but the level declined rapidly and by day 50 after birth the liver was... more
The development of the liver, bone marrow and spleen have been investigated in the stripe-faced dunnart. At birth, the liver was undergoing haematopoiesis but the level declined rapidly and by day 50 after birth the liver was histologically mature. Both the bone marrow and spleen were non-haematopoietic at birth but initiated haematopoiesis shortly thereafter. Bone marrow was initially detected at day 11 postpartum. By 57 days after birth, adipocytes had infiltrated the marrow and were abundant by day 60 after birth. Mitotic cells were observed in remaining areas of marrow until at least 170 days postpartum. The spleen at birth was undifferentiated, with trabeculae appearing by day 42. Red and white pulp areas became apparent by day 43 and were well defined by day 57 after birth. In summary, the pattern of the development of the liver, bone marrow and spleen in the stripe-faced dunnart were similar to that observed in eutherians and other metatherians studied to date.
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This paper describes the initial appearance and distribution of mature T and B cells in the developing immune tissues of the stripe-faced dunnart (Sminthopsis macroura) based on the use of species cross-reactive antibodies to the... more
This paper describes the initial appearance and distribution of mature T and B cells in the developing immune tissues of the stripe-faced dunnart (Sminthopsis macroura) based on the use of species cross-reactive antibodies to the lymphocyte cell surface markers CD3, CD5 and CD79b. At birth no mature T or B cells were detected in the liver or bone marrow using anti-CD3, anti-CD5 or anti-CD79b antibodies. T cells were detected in the thymus with anti-CD3 by day 12 and anti-CD5 by day 50 postpartum, and T cells in the spleen were detected by day 43 and day 80 postpartum using anti-CD3 and anti-CD5, respectively. B cells were observed in the dunnart spleen by 43 days after birth. CD3- and CD79b-positive cells were detected in the lymph nodes by 50 days and CD5 by day 15 after birth, and in the gut-associated lymphoid tissues by day 50 and anti-CD5 by day 57 postpartum. The development and distribution of T and B cells in the immune tissues of dunnart pouch young is similar to that described in other marsupial species. Low numbers or absence of mature lymphocytes in immune tissues of early pouch young dunnarts further support the proposition that young marsupials are reliant on non-specific defence strategies and/or maternal strategies for a significant period of their time of development in the pouch.
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The distribution of T- and B-cells in the developing lymphoid and immunohaematopoietic tissues of the tammar wallaby were investigated using antibodies to the mature cell surface markers, CD3, CD5 and CD79b. In the thymus, CD3- and... more
The distribution of T- and B-cells in the developing lymphoid and immunohaematopoietic tissues of the tammar wallaby were investigated using antibodies to the mature cell surface markers, CD3, CD5 and CD79b. In the thymus, CD3- and CD5-positive T-cells were first observed at day 12 postpartum whilst rare B-cells were first detected at day 23. Both T- and B-lymphocytes were first stained on day 21 postpartum in the spleen and day 24 in lymph nodes. In one sample from a 7-day-old animal, rare CD79b-positive (CD79b+) lymphocytes were observed in the gut-associated lymphoid tissues. However, CD3+ cells were not apparent until day 12 and CD5+ cells were not detected until day 74 postpartum. No lymphocytes were detected in liver or bone marrow samples and no bronchus-associated lymphoid tissues were observed. The pattern of development and the distribution of T- and B-cells in the lymphoid and immunohaematopoietic tissues were similar to those observed in eutherian mammals and in limited studies of other metatherians. However, the detection of apparently mature T- and B-cells in the thymus and gut-associated lymphoid tissues (GALT) at the same postnatal age highlights the need for a more substantial study of the development of GALT. This is, at present, limited by availability of marsupial-specific antibodies.
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The lymphoid and immunohaematopoietic tissues of the embryonic and full-term brushtail possums was investigated histologically and immunohistochemically using antibodies to the T- and B-cell markers, CD3, CD5, CD79a and CD79b. No clearly... more
The lymphoid and immunohaematopoietic tissues of the embryonic and full-term brushtail possums was investigated histologically and immunohistochemically using antibodies to the T- and B-cell markers, CD3, CD5, CD79a and CD79b. No clearly defined thymus, bone marrow, spleen, lymph nodes, gut-associated lymphoid tissues or bronchus-associated lymphoid tissues were observed histologically. The liver was haematopoietic and contained erythrocytic and granulocytic precursors. No mature lymphocytes were observed histologically or detected using antibodies to T- and B-cell markers in any of the tissues. These results are consistent with other studies of the early postnatal tissues of other marsupials and support the proposition that neonatal marsupials are substantially reliant on maternal immunological protection at the time of birth and for a significant period of pouch life.
Research Interests: Cognitive Science, Immunohistochemistry, Hematopoiesis, Hematopoietic Stem Cells, Pregnancy, and 14 moreFemale, Animals, Bone marrow, Medical Physiology, T lymphocytes, Veterinary Anatomy and Embryology, Biological markers, B Lymphocytes, Lymph Node, Embryos, Opossums, Neurosciences, Lymphoid Tissue, and Maternal-fetal exchange
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The lymphoid tissues of the metatherian mammal, the adult tammar wallaby, Macropus eugenii, were investigated using immunohistochemical techniques. Five cross-reactive antibodies previously shown to recognize surface markers in marsupial... more
The lymphoid tissues of the metatherian mammal, the adult tammar wallaby, Macropus eugenii, were investigated using immunohistochemical techniques. Five cross-reactive antibodies previously shown to recognize surface markers in marsupial tissues and five previously untested antibodies were used. The distribution of T-cells in the tissue beds of spleen, lymph node, thymus, gut-associated lymphoid tissue (GALT) and bronchus-associated lymphoid tissue (BALT) was documented using antibodies to CD3 and CD5. Similarly, B-cells were identified in the same tissues using anti-CD79b. Antibodies to CD8, CD31, CD79a and CD68 failed to recognize cells in these tissue beds. In general the pattern of cellular distribution identified using these antibodies was similar to that observed in other marsupial and eutherian lymphoid tissues. This study provides further information on the commonality of lymphoid tissue structure in the two major groups of extant mammals, metatherians and eutherians.
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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... more
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 organisms including Corynebacterium spp., Micrococcus spp. and Staphylococcus spp. were the most frequent isolates, regardless of reproductive status. Whilst Gram-negative rods Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes, and Escherichia coli were found in pouches with and without pouch young, but not in pouches close to oestrus, at the time of birth or in the presence of very young animals (<6 days). While pouches without pouch young displayed the greatest diversity of bacterial species, there were still significant numbers of bacterial species in those containing pouch young. Results suggest that the microbial population of the tammar pouch does not seriously compromise the well-being of the young animal during crucial stages of immunological development. The data are consistent with observations on the microflora of the quokka pouch but not with data from the koala.Les changements dans la diversité et la composition des populations de bactéries aérobies, isolées de la poche du tammar wallaby et cultivées, ont été suivis au cours de la période précédant l'oestrus, au moment de la naissance du jeune et après la naissance, dans des poches avec ou sans jeune. Trente différentes espèces de bactéries ont été isolées de la poche de 12 animaux: 25 espèces isolées de poches vides, neuf espèces de poches contenant un jeune de moins de trois semaines et neuf espèces de poches contenant un jeune de plus de trois semaines. Les bactéries Gram-positives Corynebacterium spp., Micrococcus spp. et Staphylococcus spp. ont été les plus fréquemment rencontrées, et ce quelque soit la période du cycle reproductif. Les espèces Gram-negatives Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter aerogenes, et Escherichia coli ont été constamment isolées de poches vides, lorsque le tammar n'était ni en période proche de l'oestrus, ni proche de la naissance et ont été constamment isolées de poches contenant un jeune si celui-ci était agé de plus de six jours. Les plus grandes diversités spécifiques ont été relevées dans les poches vides, bien que les poches contenant un jeune ont toujours présenté un nombre significant d'espèces bactériennes. Les résultats suggèrent que les différentes populations bactériennes présentes dans la poche du tammar ne semblent affecter ni le bon dévelopement, ni la santé du jeune dans la poche, spécialement lors du dévelopement de ses capacités immunologiques. Ces résultats sont en accord avec ceux ceux obtenus pour le quokka, mais differents de ceux obtenus pour le koala.