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surveillance and movements of virginia opossum (didelphis virginiana) in the bovine tuberculosis region of michigan.wildlife reservoir hosts of bovine tuberculosis (btb) include eurasian badgers (meles meles) and brushtail possum (trichosurus vulpecula) in the uk and new zealand, respectively. similar species warrant further investigation in the northern lower peninsula of michigan, usa due to the continued presence of btb on cattle farms. most research in michigan, usa has focused on interactions between white-tailed deer (odocoileus virginianus) and cattle (bos taurus) for the transmission of the infectious ...201323531427
a novel approach to assess the probability of disease eradication from a wild-animal reservoir host.surveying and declaring disease freedom in wildlife is difficult because information on population size and spatial distribution is often inadequate. we describe and demonstrate a novel spatial model of wildlife disease-surveillance data for predicting the probability of freedom of bovine tuberculosis (caused by mycobacterium bovis) in new zealand, in which the introduced brushtail possum (trichosurus vulpecula) is the primary wildlife reservoir. using parameters governing home-range size, proba ...201323339965
sustained protection against tuberculosis conferred to a wildlife host by single dose oral vaccination.vaccination of wildlife against bovine tuberculosis (tb) is being considered by several countries to reduce the transmission of mycobacterium bovis infection to livestock. in new zealand, where introduced brushtail possums (trichosurus vulpecula) are the major wildlife hosts, we have previously shown that repeat applications of a lipid-encapsulated oral bacille calmette-guerin (bcg) vaccine reduce the incidence of naturally acquired tb in wild possums. here we extend this conceptual demonstratio ...201323246543
importance and mitigation of the risk of spillback transmission of mycobacterium bovis infection for eradication of bovine tuberculosis from wildlife in new zealand.introduced brushtail possums (trichosurus vulpecula) are wildlife maintenance hosts for mycobacterium bovis in new zealand, often living sympatrically with other potential hosts, including wild red deer (cervus elaphus scoticus). population control of possums has been predicted to eradicate tuberculosis (tb) from new zealand wildlife ; however, there is concern that long-lived m. bovis-infected deer could represent a ‘ spillback’ risk for tb re-establishment (particularly when possum populations ...201323211646
mortality rate and gross pathology due to tuberculosis in wild brushtail possums (trichosurus vulpecula) following low dose subcutaneous injection of mycobacterium bovis.gross pathology due to tuberculosis can be established experimentally in brushtail possums (trichosurus vulpecula) within 7 weeks of injection of virulent mycobacterium bovis into subcutaneous connective tissues of the peripheral limbs. this pathology involves lymphadenomegaly and development of gross lesions in peripheral lymph nodes, with subsequent gross lesions in the lungs and reticuloendothelial organs. using this artificial infection model, we here assessed the mortality rate for possums ...201323063260
percutaneous interdigital injection of mycobacterium bovis as a model for tuberculous lesion development in wild brushtail possums (trichosurus vulpecula).brushtail possums (trichosurus vulpecula) are the major wildlife reservoir of mycobacterium bovis, the causative agent of bovine tuberculosis (btb), in new zealand. primary diagnosis of btb in wild possums is by palpation to detect peripheral lymphadenomegaly followed by necropsy examination, which frequently identifies gross tuberculous lesions in the peripheral lymph nodes and lungs. experimental infection studies were conducted with wild possums in an attempt to emulate field btb, focussing o ...201322749650
clinical, microbiological and pathological findings of mycobacterium ulcerans infection in three australian possum species.buruli ulcer (bu) is a skin disease caused by mycobacterium ulcerans, with endemicity predominantly in sub-saharan africa and south-eastern australia. the mode of transmission and the environmental reservoir(s) of the bacterium and remain elusive. real-time pcr investigations have detected m. ulcerans dna in a variety of australian environmental samples, including the faeces of native possums with and without clinical evidence of infection. this report seeks to expand on previously published fin ...201424498451
validation of various parasite detection tests for use in the australian marsupials quenda ( isoodon obesulus) and brushtail possums ( trichosurus vulpecula).we aimed to validate the use of 1) the modified agglutination test and a polymerase chain reaction (pcr) protocol in detecting toxoplasma gondii infection in quenda ( isoodon obesulus) and brushtail possums ( trichosurus vulpecula); 2) immunofluorescence microscopy of feces and a pcr and sequencing protocol in detecting giardia spp. infection in quenda; and 3) a fecal flotation protocol in detecting gastrointestinal helminth infections of quenda. quenda and brushtail possum carcasses, and sample ...201727927910
hematologic and serum biochemical reference ranges and an assessment of exposure to infectious diseases prior to translocation of the threatened western ringtail possum (pseudocheirus occidentalis).health screening of animals before translocation is important to minimize the risk of pathogen transmission between sites and species. reintroduction has been incorporated into management of the endangered western ringtail possum (pseudocheirus occidentalis) to mitigate for habitat loss within the species' core range in southwestern australia. between november 2005 and march 2008 we screened 47 wild and 24 captive p. occidentalis and 68 sympatric common brushtail possums (trichosurus vulpecula h ...201324502710
marsupial cardiac myosins are similar to those of eutherians in subunit composition and in the correlation of their expression with body size.cardiac myosins and their subunit compositions were studied in ten species of marsupial mammals. using native gel electrophoresis, ventricular myosin in macropodoids showed three isoforms, v(1), v(2) and v(3), and western blots using specific anti-alpha- and anti-beta-cardiac myosin heavy chain (myhc) antibodies showed their myhc compositions to be alphaalpha, alphabeta and betabeta, respectively. atrial myosin showed alphaalpha myhc composition but differed from v(1) in light chain composition. ...200716988832
marsupial cells in long-term culture.cell lines have been developed from several species of australian marsupials and studied during long-term growth. cell lines developed from macropodid skin or heart tissues all had reproducible finite life-spans. however, cell lines developed from dasyurids showed bariable behavior in culture: lines developed from antechinus stuartii and dasyurus viverrinus had finite life-spans, while lines developed from sminthopsis crassicaudata had indefinite life-spans. s. crassicaudata lines usually became ...1977559639
connections of the auditory cortex of the brush-tailed possum, trichosurus vulpecula.the afferent connections of the auditory cortex of the acallosal marsupial trichosurus vulpecula have been studied using the retrograde transport of horseradish peroxidase. the enzyme was applied by electrophoresis from a micropipette previously used to define physiologically the organization of the auditory cortex. three major (lateral, dorsomedial and ventromedial) sectors of the medial geniculate contribute axons to the ipsilateral auditory cortex; the connections from at least the lateral se ...19836303495
relationships of the visual cortex in the marsupial brush-tailed possum, trichosurus vulpecula, a horseradish peroxidase and autoradiographic study.the ascending and descending relationships of visual cortex in trichosurus were determined using hrp and autoradiographic methods. the visual thalamus, lgnd and lp, was found to project to three cytoarchitecturally distinct areas of cortex with each of these regions displaying differing patterns of connectivity with other centres. the striate and peristriate cortices received homotypically organized projections from lgnd as well as projections from both divisions of lp. the posterior parietal co ...19807216909
the organization of neocortical projections from the ventroposterior thalamic complex in the marsupial brush-tailed possum, trichosurus vulpecula: a horseradish peroxidase study.retrograde transport of horseradish peroxidase (hrp) was used to determine the extent and some of the organizational details of the cortical projection of the ventroposterior thalamic complex (vp) in the marsupial brush-tailed possum, trichosurus vulpecula. the cortical projection field of vp is coincident with si as determined by electrophysiological methods, and would appear not to overlap fully the primary motor cortex. thus, in trichosurus it appears that the motor and somatic sensory cortic ...1978689987
the organization of the facial nucleus of the brush-tailed possum (trichosurus vulpecula).the facial nucleus of the brush-tailed possum has been studied using nissl staining and the horseradish peroxidase (hrp) retrograde tracing technique. in nissl stained sections the nucleus is seen to comprise five distinct subnuclei. injections of hrp into individual facial muscle groups have shown that these subnuclei reflect the peripheral innervation pattern of efferents from this nucleus. although in most cases, injection of hrp into a single facial muscle group resulted in the labelling of ...197765363
movements and habitat preferences of pests help to improve population control: the case of common brushtail possums in a new zealand dryland ecosystem.introduced brushtail possums are controlled in new zealand to mitigate their spread of bovine tuberculosis in livestock. given the low rainfall and extreme variation in seasonal temperatures in dryland areas of the south island, the habitats of possums in these areas differ in many respects from those in the rest of new zealand. we investigated the movements and habitat preferences of possums at two dryland sites to identify where they aggregate following population control by using gps collars ...201726853520
assessing movements of brushtail possums (trichosurus vulpecula) in relation to depopulated buffer zones for the management of wildlife tuberculosis in new zealand.in new zealand, managing the threat of bovine tuberculosis (tb) to livestock includes population reduction of potentially infectious wildlife, primarily the brushtail possum (trichosurus vulpecula). population control is often targeted on forested buffer zones adjacent to farmland, in order to limit movements of possums across the buffer and reduce the risk of disease transmission to livestock. to assess the effectiveness of buffers in protecting livestock we analysed gps telemetry data from pos ...201526689918
quantifying short-term foraging movements in a marsupial pest to improve targeted lethal control and disease surveillance.in new zealand, the introduced marsupial brushtail possum (trichosurus vulpecula) is a pest species subject to control measures, primarily to limit its ability to transmit bovine tuberculosis (tb) to livestock and for conservation protection. to better define parameters for targeted possum control and tb surveillance, we here applied a novel approach to analyzing gps data obtained from 44 possums fitted with radio-tracking collars, producing estimates of the animals' short-term nocturnal foragin ...201525811977
a strategic approach to eradication of bovine tb from wildlife in new zealand.a review and amendment of new zealand's national pest management strategy for bovine tuberculosis (tb) has led to adoption of new strategy objectives for localized eradication of disease from the principal wildlife maintenance host and infecting vector for farmed cattle and deer, the brushtail possum trichosurus vulpecula. historic programmes have been based on management of disease within herds and control of wildlife directed towards reducing infected herd prevalence. from july 2011, the tb st ...201324171853
comparison of ranging behaviour in a multi-species complex of free-ranging hosts of bovine tuberculosis in relation to their use as disease sentinels.sentinel species are increasingly used by disease managers to detect and monitor the prevalence of zoonotic diseases in wildlife populations. characterizing home-range movements of sentinel hosts is thus important for developing improved disease surveillance methods, especially in systems where multiple host species co-exist. we studied ranging activity of major hosts of bovine tuberculosis (tb) in an upland habitat of new zealand: we compared home-range coverage by ferrets (mustela furo), wild ...201323433406
in vitro hepatic microsomal metabolism of meloxicam in koalas (phascolarctos cinereus), brushtail possums (trichosurus vulpecula), ringtail possums (pseudocheirus peregrinus), rats (rattus norvegicus) and dogs (canis lupus familiaris).quantitative and qualitative aspects of in vitro metabolism of the non-steroidal anti-inflammatory drug meloxicam, mediated via hepatic microsomes of specialized foliage (eucalyptus) eating marsupials (koalas and ringtail possums), a generalized foliage eating marsupial (brushtail possum), rats, and dogs, are described. using a substrate depletion method, intrinsic hepatic clearance (in vitro clint) was determined. significantly, rates of oxidative transformation of meloxicam, likely mediated vi ...201424345479
contingency discriminability, matching, and bias in the concurrent-schedule responding of possums (trichosurus vulpecula).six possums (trichosuruus vulpecula) responded under dependent concurrent variable-interval variable-interval schedules of reinforcement. over 15 conditions, barley-carob was one reinforcer with the other reinforcer consisting of coco pops, coconut, or a barley-carob mixture with 0%, 2%, 4%, or 6% salt added to the barley. the schedules were both variable-interval 40 s. as has been found with other species, behavior on the concurrent schedules was biased by the type of feed, with the 6% salt and ...200312908759
prevalence, genetic diversity and potential clinical impact of blood-borne and enteric protozoan parasites in native mammals from northern australia.a molecular survey was conducted to provide baseline information on the prevalence, genetic diversity and potential clinical impacts of blood-borne and enteric protozoans in native wild mammals from the northern territory (nt). a total of 209 blood and 167 faecal samples were collected from four target species; the northern brown bandicoot (isoodon macrourus), common brushtail possum (trichosurus vulpecula), northern quoll (dasyurus hallucatus) and brush-tailed rabbit-rat (conilurus penicillatus ...201728408215
mitochondrial genomes of a bandicoot and a brushtail possum confirm the monophyly of australidelphian marsupials.recent molecular analyses suggest that the position of bandicoots is the major difficulty in determining the root of the tree of extant marsupials. to resolve this, we analyse mitochondrial genome sequences of a bandicoot (isoodon macrourus) and a brushtail possum (trichosurus vulpecula) together with the previously available marsupial mitochondrial genomes, the virginia opossum (didelphis virginiana) and the wallaroo (macropus robustus). analyses of mitochondrial protein-coding and rna genes st ...200111454299
a light-microscopic immunocytochemical study of the endocrine pancreas in the australian brush-tailed possum (trichosurus vulpecula).the endocrine pancreas of the australian brush-tailed possum (trichosurus vulpecula) was investigated by means of immunocytochemistry using the avidin-biotin-peroxidase technique. this was a light microscopic study using this established technique. serial paraffin sections were stained individually with primary antibodies for glucagon, insulin, somatostatin, and pancreatic polypeptide (pp), showing the same islet. cells immunoreactive to glucagon, insulin, somatostatin and pp were found in endoc ...19921380858
morphological and molecular description of ixodes woyliei n. sp. (ixodidae) with consideration for co-extinction with its critically endangered marsupial host.taxonomic identification of ticks obtained during a longitudinal survey of the critically endangered marsupial, bettongia penicillata gray, 1837 (woylie, brush-tailed bettong) revealed a new species of ixodes latrielle, 1795. here we provide morphological data for the female and nymphal life stages of this novel species (ixodes woyliei n. sp.), in combination with molecular characterisation using the mitochondrial cytochrome c oxidase subunit 1 gene (cox1). in addition, molecular characterisatio ...201728173840
characterization of the intrinsic and extrinsic innervation of the gall bladder epithelium in the australian brush-tailed possum (trichosurus vulpecula).intrinsic neurones of the gall bladder modulate its function. nitric oxide synthase (nos) and vasoactive intestinal polypeptide (vip) are present in gall bladder neurones and nitric oxide and vip modulate its epithelial functions. as an extensive extrinsic innervation of the gall bladder is also present, the source of the epithelial innervation is unclear. in this study the source of the gall bladder epithelial innervation is defined. immunoreactivity for vip, nos, substance p (sp), calcitonin g ...200312846726
ontogenetic and phylogenetic transformations of the ear ossicles in marsupial mammals.this study is based on the examination of histological sections of specimens of different ages and of adult ossicles from macerated skulls representing a wide range of taxa and aims at addressing several issues concerning the evolution of the ear ossicles in marsupials. three-dimensional reconstructions of the ear ossicles based on histological series were done for one or more stages of monodelphis domestica, caluromys philander, sminthopsis virginiae, trichosurus vulpecula, and macropus rufogri ...200211835361
cyanide induced aversions in the possum (trichosurus vulpecula): effect of route of administration, dose, and formulation.possums (trichosurus vulpecula) are new zealand's main vertebrate pest. control practices using poisons are likely to remain the most cost effective methods for the immediate future but poisons may be avoided in the field. a series of experiments were conducted to determine whether cyanide bait avoidance involved conditioned food aversions (cfa) induced by sublethal cyanide ingestion. food aversions were conditioned in three experiments using intraperitoneal or oral routes of administration with ...19957568429
integrating the costs of plant toxins and predation risk in foraging decisions of a mammalian herbivore.foraging herbivores must satisfy their nutrient requirements in a world of toxic plants while also avoiding predators. plant toxins and perceived predation risk at food patches should both reduce patch residency time, but the relative strengths of these factors on feeding decisions has rarely been quantified. using an arboreal generalist herbivore, the common brushtail possum trichosurus vulpecula, we tested the effects on food intake of the plant toxin, cineole, and regurgitated pellets from on ...201020652597
transmission of chagas' disease to the australian marsupial trichosurus vulpecula. 195114835791
four species of arboreal folivore show differential tolerance to a secondary metabolite.the marsupials that eat eucalyptus in south-eastern australia provide an example of animals with similar niche requirements occurring sympatrically. they certainly differ in size, ranging from about 1 kg in the greater glider (petauroides volans) and the closely related common ringtail possum (pseudocheirus peregrinus), to 4 kg (common brushtail possum, trichosurus vulpecula) and up to 15 kg in the koala (phascolarctos cinereus). all species, however, may eat considerable amounts of eucalypt fol ...201424974269
long-term dynamics of a fragmented rainforest mammal assemblage.habitat fragmentation is a severe threat to tropical biotas, but its long-term effects are poorly understood. we evaluated longer-term changes in the abundance of larger (>1 kg) mammals in fragmented and intact rainforest and in riparian "corridors" in tropical queensland, with data from 190 spotlighting surveys conducted in 1986-1987 and 2006-2007. in 1986-1987 when most fragments were already 20-50 years old, mammal assemblages differed markedly between fragmented and intact forest. most vulne ...200818637907
differential susceptibility to eucalyptus secondary compounds explains feeding by the common ringtail (pseudocheirus peregrinus) and common brushtail possum (trichosurus vulpecula).the effect of two plant secondary metabolites, tannins and formylated phloroglucinol compounds (fpcs), on the intake of eucalyptus foliage by common ringtail (pseudocheirus peregrinus) and common brushtail possums (trichosurus vulpecula) was studied. we manipulated the amount of tannin that was free to bind with protein by coating foliage with polyethylene glycol 4000 (peg) and relied on natural intraspecific variation in fpc concentrations. in contrast to ringtail possums, brushtail possums sho ...200312592445
administration of a 5ht3 receptor antagonist increases the intake of diets containing eucalyptus secondary metabolites by marsupials.the effect of a naturally occurring plant phenolic constituent (the acylphloroglucinol derivative, jensenone, derived from eucalyptus jensenii) on the food intake of two folivorous marsupials, the common ringtail (pseudocheirus peregrinus) and the common brushtail possum (trichosurus vulpecula) was studied. when fed diets containing varying concentrations of jensenone, both species regulated their intake of jensenone so as not to exceed a ceiling intake. this ceiling was about twice as high for ...19989871345
histological and immunohistological investigation of alimentary tract lymphoid tissue in the koala (phascolarctos cinereus), brushtail possum (trichosurus vulpecula) and ringtail possum (pseudocheirus peregrinus).the histological appearance and distribution of t cells, b cells and plasma cells were investigated for oropharyngeal tonsils, small intestinal lymphoid aggregations (peyer's patches), caecocolic lymphoid patches and mesenteric lymph nodes of koalas (phascolarctos cinereus), common brushtail possums (trichosurus vulpecula) and common ringtail possums (pseudocheirus peregrinus). the histological organisation and distribution of lymphoid cell subpopulations of these tissues were similar to those d ...19968621326
the distribution of organised lymphoid tissue in the alimentary tracts of koalas (phascolarctos cinereus) and possums (trichosurus vulpecula and pseudocheirus peregrinus).the anatomical arrangement of organised lymphoid tissues of the alimentary tract for 3 australian marsupials, the koala (phascolarctos cinereus), the common brushtail possum (trichosurus vulpecula and the common ringtail possum (pseudocheirus peregrinus), was determined by gross dissection and acetic acid treatment. oropharyngeal tonsils were consistently found in the dorsolateral wall of the caudal oropharynx in all 3 species and additionally in the ventral soft palate of the koala. aggregated ...19968621325
effect of dietary terpenes on glucuronic acid excretion and ascorbic acid turnover in the brushtail possum (trichosurus vulpecula).1. glucuronic acid was excreted in the urine of the brushtail possum, trichosurus vulpecula, in response to dietary terpenes (essential oils found in eucalyptus foliage). 2. the relationship between urinary glucuronic acid and the estimated terpene content of the diet was not equimolar, but varied from 1-17%, with levels of 5-39% found in animals maintained on terpenes or eucalypt leaves for several weeks. 3. blood levels of ascorbate and the turnover rate of ascorbate were increased in the brus ...19883356132
optimising the application of multiple-capture traps for invasive species management using spatial simulation.internationally, invasive vertebrate species pose a significant threat to biodiversity, agricultural production and human health. to manage these species a wide range of tools, including traps, are used. in new zealand, brushtail possums (trichosurus vulpecula), stoats (mustela ermine), and ship rats (rattus rattus) are invasive and there is an ongoing demand for cost-effective non-toxic methods for controlling these pests. recently, traps with multiple-capture capability have been developed whi ...201525782018
plant secondary metabolites as mammalian feeding deterrents: separating the effects of the taste of salicin from its post-ingestive consequences in the common brushtail possum (trichosurus vulpecula).the effect of the phenolic glycoside, salicin, on food intake of the common brushtail possum (trichosurus vulpecula) was studied in a series of feeding experiments. increasing the concentration of salicin in a diet of fruits and cereals led to significant reductions of food intake in the short term (6 days). after prolonged (20 days) exposure to salicin, food intake (19 g kg(-0.75) day(-1)) was still reduced relative to controls (31 g kg(-0.75) day(-1)) but not reduced to the same extent as in t ...010841258
bird-repellent effects on bait efficacy for control of invasive mammal pests.repellents to reduce crop damage from birds and mammals have been investigated extensively, but their efficacy in reducing risk to non-target birds in aerial poisoning operations for control of mammal pests is less known. we assessed the impact on bait acceptability, palatability and kill efficacy for captive wild rats (rattus rattus l.) and possums (trichosurus vulpecula kerr) of adding bird repellents (anthraquinone and d-pulegone) to baits used for their control in food choice trials.201525143303
bait aggregation to reduce cost and toxin use in aerial 1080 baiting of small mammal pests in new zealand.the metabolic toxin sodium fluoroacetate ('compound 1080') is widely used for controlling introduced mammalian pests in new zealand. for large-scale operations, 1080 is distributed aerially in bait to kill brushtail possums (trichosurus vulpecula kerr) and ship rats (rattus rattus l.). while usually successful in reducing pest populations by > 80%, widespread distribution of toxic bait is relatively expensive and raises concerns from some members of the public. here, trials with spatial aggregat ...201222615267
demography in relation to population density in two herbivorous marsupials: testing for source-sink dynamics versus independent regulation of population size.we compared demography of populations along gradients of population density in two medium-sized herbivorous marsupials, the common brushtail possum trichosurus vulpecula and the rufous bettong aepyprymnus rufescens, to test for net dispersal from high density populations (acting as sources) to low density populations (sinks). in both species, population density was positively related to soil fertility, and variation in soil fertility produced large differences in population density of contiguous ...200515583939
lysine and glutamate transport in the erythrocytes of common brushtail possum, tammar wallaby and eastern grey, kangaroo.it was recently coincidentally discovered, using 1h nmr spectroscopy, that the erythrocytes of two species of australian marsupials, tammar wallaby (macropus eugenii) and bettong (bettongia penicillata), contain relatively high concentrations of the essential amino acid lysine (agar ns, rae cd, chapman be, kuchel pw. comp biochem physiol 1991;99b:575-97). hence, in the present work the rates of transport of lysine into the erythrocytes from the common brushtail possum (dactylopsilia trivirgata) ...19989773487
cytoplasmic maturation of the marsupial oocyte during the periovulatory period.during the period immediately before ovulation, the oocytes of most eutherian and marsupial mammals complete the first meiotic maturation division and extrude the first polar body. in marsupials, this phase of nuclear maturation is accompanied by an increase in size of the egg and maturation of cytoplasmic components. oocytes from at least four marsupial species, trichosurus vulpecula, macropus eugenii, bettongia penicillata and monodelphis domestica, continue to grow after formation of the foll ...19968870076
unexpected oocyte growth after follicular antrum formation in four marsupial species.during examination of maturing preovulatory marsupial oocytes we noted that oocyte diameters were invariably about 50% greater than the figures reported in earlier histological studies. as all previous investigations were limited to small follicles (at most 25% the size of the ovulating follicle), the present study was initiated to examine oocyte growth during the whole period of follicular development. oocyte and follicle diameters were measured for three australian (trichosurus vulpecula, macr ...19921339855
acrosome stability in the spermatozoa of dasyurid marsupials.the spermatozoa of most marsupials lack nuclear stabilising disulfide-bonded protamines found in eutherian mammals. however, disulfide stabilisation has been observed in the acrosome of macropodid (macropus eugenii) and phalangerid (trichosurus vulpecula) marsupials. as a result this organelle, which is normally fragile in eutherian mammals, is robust and able to withstand physical and chemical challenge in these marsupials. the present study examined acrosomal characteristics of the spermatozoa ...200818255019
chemical characterization of milk oligosaccharides of the common wombat (vombatus ursinus).previous structural characterizations of marsupial milk oligosaccharides have been performed in the tammar wallaby, red kangaroo, koala, common brushtail possum and the eastern quoll. to clarify the homology and heterogeneity of milk oligosaccharides among marsupial species, which could provide information on their evolution, the oligosaccharides of wombat milk carbohydrate were characterized in this study. neutral and acidic oligosaccharides were isolated from the carbohydrate fractions of two ...201626608481
chemical characterization of milk oligosaccharides of the eastern quoll (dasyurus viverrinus).structural characterizations of marsupial milk oligosaccharides have been performed in four species to date: the tammar wallaby (macropus eugenii), the red kangaroo (macropus rufus), the koala (phascolarctos cinereus) and the common brushtail possum (trichosurus vulpecula). to clarify the homology and heterogeneity of milk oligosaccharides among marsupials, the oligosaccharides in the carbohydrate fraction of eastern quoll milk were characterized in this study. neutral and acidic oligosaccharide ...201526047593
plasma prolactin concentrations throughout lactation in the eastern quoll, dasyurus viverrinus (marsupialia:dasyuridae).blood samples were collected throughout lactation from eight d. viverrinus, and the concentrations of prolactin in the plasma determined by an heterologous, double-antibody radioimmunoassay. for the first 45-50 days of lactation concentrations fluctuated between 2 and 80 ng/ml but were generally less than 60 ng/ml. they then increased sharply to over 120 ng/ml and greater than 200 ng/ml in some animals. levels began to decline after 120-130 days of lactation and were less than 40 ng/ml in all an ...19863789990
arginine vasopressin- and oxytocin-like peptides in the testis of two australian marsupials.high performance liquid chromatography (hplc) and specific radioimmunoassay (ria) for arginine vasopressin (avp), mesotocin (mt), and oxytocin (ot) were used to identify and quantify these peptides in the testis of the brushtail possum (trichosurus vulpecula) and the northern brown bandicoot (isoodon macrourus). arginine vasopressin (0.092 +/- 0.041 ng/g) and mt (0.198 +/- 0.089 ng/g), but not ot, were found in the possum testis, while the bandicoot testis contained avp (0.061 ng/g), mt (0.108 + ...20168234012
the transfer of thyroxine from the mother to the young of the marsupials, the bandicoot (isoodon macrourus) and the possum (trichosurus vulpecula).1. the young of the bandicoot and possum are of similar weight at birth (200-250 mg) but by day 50 post-partum have weights of 100 and 20 g, respectively. the aim of this study was to determine whether the disparate growth rate was associated with a difference in the transfer of thyroxine from mother to young. 2. radioactive thyroxine was injected intramuscularly into the lactating female and 24 hr later a blood sample was obtained from the mother and the pouch young removed. the amount of radio ...19921358508
seasonal breeding in two marsupials, the bandicoot isoodon macrourus and the possum trichosurus vulpecula. 19902200044
non-invasive placentation in the marsupials macropus eugenii (macropodidae) and trichosurus vulpecula (phalangeridae) involves redistribution of uterine desmoglein-2.in mammalian pregnancy, the uterus is remodeled to become receptive to embryonic implantation. since non-invasive placentation in marsupials is likely derived from invasive placentation, and is underpinned by intra-uterine conflict between mother and embryo, species with non-invasive placentation may employ a variety of molecular mechanisms to maintain an intact uterine epithelium and to prevent embryonic invasion. identifying such modifications to the uterine epithelium of marsupial species wit ...201829243855
uterine molecular changes for non-invasive embryonic attachment in the marsupials macropus eugenii (macropodidae) and trichosurus vulpecula (phalangeridae).pregnancy in mammals requires remodeling of the uterus to become receptive to the implanting embryo. remarkably similar morphological changes to the uterine epithelium occur in both eutherian and marsupial mammals, irrespective of placental type. nevertheless, molecular differences in uterine remodeling indicate that the marsupial uterus employs maternal defences, including molecular reinforcement of the uterine epithelium, to regulate embryonic invasion. non-invasive (epitheliochorial) embryoni ...201728688214
uterine remodelling during pregnancy and pseudopregnancy in the brushtail possum (trichosurus vulpecula; phalangeridae).the formation of a placenta is critical for successful mammalian pregnancy and requires remodelling of the uterine epithelium. in eutherian mammals, remodelling involves specific morphological changes that often correlate with the mode of embryonic attachment. given the differences between marsupial and eutherian placentae, formation of a marsupial placenta may involve patterns of uterine remodelling that are different from those in eutherians. here we present a detailed morphological study of t ...201728397980
chemical characterization of milk oligosaccharides of the common brushtail possum (trichosurus vulpecula).structural characterizations of marsupial milk oligosaccharides have been performed in only three species: the tammar wallaby, the red kangaroo and the koala. to clarify the homology and heterogeneity of milk oligosaccharides among marsupials, 21 oligosaccharides of the milk carbohydrate fraction of the common brushtail possum were characterized in this study. neutral and acidic oligosaccharides were separated from the carbohydrate fraction of mid-lactation milk and characterized by (1)h-nuclear ...201424906475
molecular identification and expression of lyn tyrosine kinase isoforms in marsupials.lyn is a tyrosine kinase molecule required for modulation of signalling cascades in cell populations including b lymphocytes of the mammalian immune system. we have characterised the coding domain of the marsupial lyn gene of two macropod marsupials; the tammar wallaby (macropus eugenii) and the bridled nailtail wallaby (onychogalea fraenata) and show the co-expression of two lyn isoforms in cells and tissues of these and three other marsupials (brush-tail possum, trichosurus vulpecula; american ...201323522727
a quantitative study of the morphological development and bacterial colonisation of the gut of the tammar wallaby macropus eugenii eugenii and brushtail possum trichosurus vulpecula during in-pouch development.we compared the rates of change of various morphological parameters of the stomach, small intestine, caecum and colon of tammar wallabies and brushtail possums with body mass during in-pouch development. these were correlated with changes in the numbers of bacterial species in the various gut segments. in the pouch-young of both species, the wet tissue masses of all gut segments increased with body mass in a positively allometric manner (i.e. with a body mass exponent > 1), suggesting that the m ...200616819652
ontogeny and pathway of formation of 5alpha-androstane-3alpha,17beta-diol in the testes of the immature brushtail possum trichosurus vulpecula.the testicular androgen 5alpha;-androstane-3alpha,17beta-diol (androstanediol) mediates virilisation in pouch young of a marsupial, the tammar wallaby, and is the principal androgen formed in immature rodent testes. to chart the pattern of androstanediol formation in another marsupial species, the testes or fragments of testes from brushtail possums (trichosurus vulpecula) that spanned the age range from early pouch young to mature adults were incubated with (3)h-progesterone and the products we ...200516263065
characterisation of antisera to recombinant iga of the common brushtail possum (trichosurus vulpecula).one of the limiting factors in understanding immune responses in marsupials is the scarcity of marsupial specific immunological reagents. this paper describes the characterisation of an antiserum raised against a recombinant protein of the constant region of the heavy chain of iga (c(alpha)) of the common brushtail possum (trichosurus vulpecula). the availability of a marsupial specific anti-iga provides a useful tool for the characterisation of mucosal immune responses in possums. anti-c(alpha) ...200212088648
role of pgf2alpha and oxytocin in parturition in the brushtail possum (trichosurus vulpecula).maturation of the fetal pituitary and adrenal glands allows the secretion of cortisol, which in turn leads to an increase in prostaglandin and mesotocin production. the production of prostaglandin and mesotocin results in an increase in uterine contractions and initiates birth in marsupials. the major metabolite of pgf(2alpha), 13,14-dihydro-15-keto-prostaglandin f(2alpha) (pgfm), has been found in the plasma of the possum at the time of birth and administration of pgf(2alpha) to female possums ...200211882020
differential expression of the whey acidic protein gene during lactation in the brushtail possum (trichosurus vulpecula).the whey acidic protein (wap) is a whey protein found in the milk of a number of species. we have isolated and characterised a wap cdna clone from the brushtail possum (trichosurus vulpecula) and examined its expression in the mammary gland. the amino acid sequences of wap from the possum and another marsupial, the tammar wallaby, share 69% identity, however, less sequence identity exists between the marsupial and eutherian wap sequences (30-37%). the possum and tammar wap genes consist of three ...200111779633
therapeutics of companion exotic marsupials.exotic marsupials are becoming popular companion pets, yet little pharmacologic information is available to the practitioner. species include sugar gliders (petarus breviceps), south american (brazilian) short-tailed opossums (monodelphis domestica), brushtail possum or "phalanger" (trichosurus vulpecula), and wallabies: bennett's (macropus rufogriseus rufogriseus) and tammar or dama (macropus eugenii). guidelines for logical choices of medications based on allometric scaling, gastrointestinal t ...200011228826
karyotype relationships between four distantly related marsupials revealed by reciprocal chromosome painting.marsupial karyotypes have shown extensive conservation even between distantly related groups with a high diversity of life forms and reproductive biology. banding analysis has been the main test for assessing their homologies and chromosome rearrangements. more recently, cross-species reciprocal chromosome painting has been developed and applied to several mammalian species and has shown homologies and rearrangements not revealed by banding analysis. karyotype relationships between four marsupia ...199910560969
acrosome formation during sperm transit through the epididymis in two marsupials, the tammar wallaby (macropus eugenii) and the brushtail possum (trichosurus vulpecula).in certain australian marsupials including the tammar wallaby (macropus eugenii) and the brushtail possum (trichosurus vulpecula), formation of the acrosome is not completed in the testis but during a complex differentiation process as spermatozoa pass through the epididymis. using transmission and scanning electron microscopy this paper defined the process of acrosome formation in the epididymis, providing temporal and spatial information on the striking reorganisation of the acrosomal membrane ...199910337954
identification, characterisation and cdna cloning of two caseins from the common brushtail possum (trichosurus vulpecula)1.two major caseins have been isolated from the milk of the common brushtailed possum (trichosurus vulpecula). these have been identified as alpha- and beta-casein on the basis of the similarity of their n-terminal sequences to those of the caseins of another marsupial (macropus eugenii). both proteins appear to exist in multiple forms. possum alpha-casein is glycosylated mainly in the form of sialic acid residues and was shown by electrospray mass spectrometry to have multiply phosphorylated form ...199910082990
phylogenetic analysis of three lipocalin-like proteins present in the milk of trichosurus vulpecula (phalangeridae, marsupialia).three proteins have been identified in the milk of the common brush tail possum. trichosurus vulpecula that from sequence analysis are members of the lipocalin family. they include beta-lactoglobulin, which appears to have two forms; a homologue to the late-lactation protein found in tammar, macropus eugenii; milk; and a novel protein termed trichosurin. whereas beta-lactoglobulin and trichosurin are both expressed throughout lactation, the late-lactation protein is not detected in samples taken ...19989493361
posttesticular development of spermatozoa of the tammar wallaby (macropus eugenii).tammar wallaby spermatozoa undergo maturation during transit through the epididymis. this maturation differs from that seen in eutherian mammals because in addition to biochemical and functional maturation there are also major changes in morphology, in particular formation of the condensed acrosome and reorientation of the sperm head and tail. of spermatozoa released from the testes, 83% had a large immature acrosome. by the time spermatozoa reached the proximal cauda epididymis 100% of sperm ha ...19979061449
pellet-freezing spermatozoa of two marsupials: the tammar wallaby, macropus eugenii, and the brushtail possum, trichosurus vulpecula.a protocol was developed for pellet-freezing spermatozoa of the tammar wallaby and the brushtail possum. seren was collected by electro-ejaculation and wallaby spermatozoa were washed by 'swim-up' into phosphate-buffered saline (pbs), whereas possum spermatozoa were not washed. wallaby spermatozoa were screened for toxicity in diluents containing a range of cryoprotectants (0-10%): dimethyl sulfoxide (dmso), ethylene glycol and propanediol. possum spermatozoa were tolerant of diluents containing ...19968870090
fluorescent localization of thiols and disulfides in marsupial spermatozoa by bromobimane labelling.the acrosome of marsupial spermatozoa is a robust structure which, unlike its placental counterpart, resists disruption by detergent or freeze/thawing and does not undergo a calcium ionophore induced acrosome reaction. in this study specific fluorescent thiol labels, bromobimanes, were used to detect reactive thiols in the intact marsupial spermatozoon and examine whether disulfides play a role in the stability of the acrosome. ejaculated brushtail possum (trichosurus vulpecula) and tammar walla ...19948185937
role of diacylglycerols and calcium in the marsupial acrosome reaction.acrosomal loss was induced in marsupial spermatozoa by an intermediate of the phosphoinositide pathway. the diacylglycerol, 1,2-dioctanoyl-sn-glycerol (dic8; 100 mumol l-1) induced acrosomal loss in 70% of brushtail possum (trichosurus vulpecula) spermatozoa and in 80% of tammar wallaby (macropus eugenii) spermatozoa. the dic8-induced acrosomal loss was not enhanced by co-incubation with calcium ionophore a23187 and occurred in ca(2+)-free medium and in the presence of the calcium chelator egta ...19938107018
differentiation of the gonads and initiation of mammary gland and scrotum development in the brushtail possum trichosurus vulpecula (marsupialia).the first appearance of the mammary and scrotal primordia and the sexual differentiation of the gonads of the brushtail possum, trichosurus vulpecula, are described. primordial germ cells were first observed, in fetuses of 7.5 mm crown-rump length, in the gonadal ridges and migrating up the dorsal mesentery. mammary primordia were first observed in fetuses of 11 mm, and scrotal primordia in those of 12 mm crown-rump length. these structures were diagnostic of female and male brushtail possums re ...19938342793
the unique stability of the marsupial sperm acrosomal membranes examined by unprotected freeze-thawing and treatment with the detergent triton x-100.in this study of the unique stability of the marsupial acrosome, experiments were carried out on the acrosomes of spermatozoa of the tammar wallaby (macropus eugenii), common brushtail possum (trichosurus vulpecula) and grey short-tailed opossum (monodelphis domestica). light microscopy showed that 4% of opossum and 15% of possum and wallaby spermatozoa lost their acrosomes after freeze-thawing. electron microscopy revealed that freeze-thawing also induced changes in the acrosomal matrix of some ...19938234885
changes in milk carbohydrates during lactation in the common brushtail possum, trichosurus vulpecula (marsupialia:phalangeridae).milk samples (186) were obtained at various stages of lactation from 27 common brushtail possums (trichosurus vulpecula). qualitative and quantitative changes in the milk carbohydrates during early and mid-lactation were similar to those previously seen in other marsupials; the principal carbohydrate was lactose early in lactation and higher oligosaccharides in mid-lactation, and the hexose concentration reached a peak during mid-lactation. however, the late-lactation milk was unusual in that th ...19892561494
changes in prolactin in peripheral plasma during lactation in the brushtail possum trichosurus vulpecula.a heterologous double-antibody radioimmunoassay has been validated for prolactin in plasma and pituitary preparations of t. vulpecula. serial dilutions of crude pituitary homogenates and plasmas from several marsupials and purified prolactin from the tammar, macropus eugenii, showed parallel dose response curves. in both male and female possums plasma prolactin concentrations increased in response to a single intravenous injection of thyrotrophin releasing hormone. plasma prolactin concentration ...19863098213
[evolution of vasopressins in marsupials: a new hormone, phenypressin (phe2-arg8-vasopressin), present in the macropodidae].a duplication of the pressor hormone has been found in some marsupials, either american species belonging to the family didelphidae or australian species belonging to the family macropodidae. two pressor peptides, lysine vasopressin and phenypressin (phe2-arg8-vasopressin) have been chemically identified in the red kangaroo (macropus rufus) and the tammar (macropus eugenii). in contrast, the brush-tailed possum (trichosurus vulpecula), a species belonging to the family phalangeridae, has a singl ...19806780214
skeletal fluorosis in marsupials: a comparison of bone lesions in six species from an australian industrial site.in this study we explored the prevalence, type, location and severity of skeletal lesions in six species of australian marsupial (macropus giganteus, notamacropus rufogriseus, wallabia bicolor, phascolarctos cinereus, trichosurus vulpecula and pseudocheirus peregrinus) from high and low-fluoride environments. lesions occurred to varying extents in all species, and lesion distribution varied with biomechanical differences in gait and mastication. bone fluoride levels increased with severity of pe ...201728185728
dental fluorosis and skeletal fluoride content as biomarkers of excess fluoride exposure in marsupials.particulate and gaseous fluoride emissions contaminate vegetation near fluoride-emitting industries, potentially impacting herbivorous wildlife in neighboring areas. dental fluorosis has been associated with consumption of fluoride-contaminated foliage by juvenile livestock and wildlife in europe and north america. for the first time, we explored the epidemiology and comparative pathology of dental fluorosis in australian marsupials residing near an aluminium smelter. six species (macropus gigan ...201526188404
cdna cloning of luteinizing hormone subunits from brushtail possum and red kangaroo.luteinizing hormone (lh) plays an important role in the reproductive cycles of all mammals. there is a large amount of both nucleotide and amino acid sequence data available for lh from eutherian mammals, but little is known about the primary structure of lh in marsupials. we have used consensus pcr primers to generate specific probes for screening pituitary cdna libraries and report the cloning of the cdnas encoding the alpha-subunit of lh (also shared by a number of other glycoprotein hormones ...19989680384
an analysis of the gene complement of a marsupial, monodelphis domestica: evolution of lineage-specific genes and giant chromosomes.the newly sequenced genome of monodelphis domestica not only provides the out-group necessary to better understand our own eutherian lineage, but it enables insights into the innovative biology of metatherians. here, we compare monodelphis with homo sequences from alignments of single nucleotides, genes, and whole chromosomes. using phyop, we have established orthologs in homo for 82% (15,250) of monodelphis gene predictions. those with single orthologs in each species exhibited a high median sy ...200717495010
unusually similar patterns of antibody v segment diversity in distantly related marsupials.a pattern of coevolution between the v gene segments of ig h and l chains has been noted previously by several investigators. species with restricted germline v(h) diversity tend to have limited germline v(l) diversity, whereas species with high levels of germline v(h) diversity have more diverse v(l) gene segments. evidence for a limited pool of v(h) but diverse v(l) gene segments in a south american opossum, monodelphis domestica, is consistent with this marsupial being an exception to the pat ...200515843567
further characterization of t cell receptor chains of marsupials.cdna clones encoding t cell receptor alpha (tcralpha) and beta (tcrbeta) from the south american opossum, monodelphis domestica were isolated and characterized. a single clone isolated encoding a tcralpha chain was full length, containing the complete v (variable), j (joining) and c (constant) regions. three partial cdna clones were isolated for tcrbeta which contained complete c sequences. phylogenetic analysis of the tcr valpha revealed that the m. domestica sequence and a sequence from the au ...200611356229
molecular cloning of the brushtail possum (trichosurus vulpecula) immunglobulin e heavy chain constant region.the immunobiology of marsupial ige is poorly understood. as a first step towards the development of immunological reagents for marsupials and to obtain a further understanding of immunoglobulin evolution, a brushtail possum (trichosurus vulpecula) mesenteric lymph node cdna library was screened for the heavy chain constant region of ige (cepsilon), using a partial cepsilon probe from the american marsupial, monodelphis domestica. the cdna sequence for t. vulpecula cepsilon was determined and fou ...199910684965
egg maturation and fertilization in marsupials.this brief review summarizes our knowledge of the morphological events that are associated with oocyte maturation and fertilization in marsupials in which it has been suggested that there are marked differences from eutherians in both the developmental timetable of oocyte maturation and in some of the processes associated with sperm-egg interaction. most of the data have been obtained from studies on four species: monodelphis domestica, sminthopsis crassicaudata, sminthopsis macroura, and tricho ...19968870085
digestion and absorption ofeucalyptus essential oils in greater glider (petauroide svolans) and brushtail possum (trichosurus vulpecula).measurements were made of the quantity and composition of the steam-volatile essential oils in gastrointestinal tract contents of greater gliders fedeucalyptus radiata foliage and brushtail possums fede. melliodora foliage. in both species, there was less oil in the stomach contents than in an equivalent mass of foliage. only minor losses of leaf oils occurred during mastication by greater gliders, and absorption from the stomach appeared to be the major reason for the difference in the oil cont ...198724301544
regional differences in electrolyte, short-chain fatty acid and water absorption in the hindgut of two species of arboreal marsupials.short-chain fatty acid, electrolyte and water absorption from the hindgut of two arboreal marsupial species, the greater glider (petauroides volans) and the brush-tail possum (trichosurus vulpecula) were studied in vivo using a single perfusion technique. qualitative and quantitative differences in the net movement of sodium, potassium and chloride were found between the different hindgut segments and between the two species. all transport processes exhibited active characteristics. net na+ tran ...19836647001
urbanization impacts on mammals across urban-forest edges and a predictive model of edge effects.with accelerating rates of urbanization worldwide, a better understanding of ecological processes at the wildland-urban interface is critical to conserve biodiversity. we explored the effects of high and low-density housing developments on forest-dwelling mammals. based on habitat characteristics, we expected a gradual decline in species abundance across forest-urban edges and an increased decline rate in higher contrast edges. we surveyed arboreal mammals in sites of high and low housing densit ...201424810286
water metabolism of two marsupials--the brush-tailed possum, trichosurus vulpecula and the rock-wallaby, petrogale inornata in the wild. 19744156252
relaxation of risk-sensitive behaviour of prey following disease-induced decline of an apex predator, the tasmanian devil.apex predators structure ecosystems through lethal and non-lethal interactions with prey, and their global decline is causing loss of ecological function. behavioural changes of prey are some of the most rapid responses to predator decline and may act as an early indicator of cascading effects. the tasmanian devil (sarcophilus harrisii), an apex predator, is undergoing progressive and extensive population decline, of more than 90% in long-diseased areas, caused by a novel disease. time since loc ...201526085584
isolation and characterisation of zona pellucida a (zpa) cdnas from two species of marsupial: regulated oocyte-specific expression of zpa transcripts.the zona pellucida (zp) is an extracellular glycoprotein coat that is deposited around the oocyte during folliculogenesis and performs several functions that relate to fertilisation and preimplantion development. in eutherian mammals it consists of three major glycoproteins--zpa, zpb, and zpc--but little is known about its molecular constitution in marsupials. we have isolated the cdna encoding the zpa homologue in two distantly related marsupial series: the possum, trichosurus vulpecula (a phal ...199910533707
atomic force microscopy and cytochemistry of chromatin from marsupial spermatozoa with special reference to sminthopsis crassicaudata.atomic force microscopy (afm) of the nuclear topology of spermatozoa from two marsupial species, smithopsis crassicaudata and trichosurus vulpecula was investigated to determine the structural organisation of the chromatin subunits. that of the former species is of special interest as it has a peripheral nucleohistone region (c2) as well as a nuclease-resistant, nucleoprotamine core region (c1). atomic force microscopy showed that the c2 region contained clusters of 120-160 nm nodules, whereas t ...19979322249
uterine expression of cp4 gene homolog in the stripe-faced dunnart, sminthopsis macroura: relationship with conceptus development and progesterone profile.the marsupial conceptus is surrounded by a uterine-secreted shell coat for 60-80% of gestation. coat protein 4 (cp4) is the only marsupial shell coat protein characterized and it has only been identified in one species, the common brushtail possum. in this possum, uterine transcription and secretion of cp4 during the oestrous cycle is biphasic and associated with the stage of conceptus development. here we cloned cp4 (sm-cp4) from a distantly related species, the stripe-faced dunnart (sminthopsi ...200919455663
how do soil nutrients affect within-plant patterns of herbivory in seedlings of eucalyptus nitens?this study assessed how the palatability of leaves of different age classes (young, intermediate and older) of eucalyptus nitens seedlings varied with plant nutrient status, based on captive feeding trials with two mammalian herbivores, red-bellied pademelons (thylogale billardierii), and common brushtail possums (trichosurus vulpecula). seedlings were grown under three nutrient treatments (low, medium and high), and we determined how palatability was related to chemical and physical characteris ...200617031701
genetic variation in resistance of eucalyptus globulus to marsupial browsers.the evolution of plant defensive traits in response to selection pressures imposed by herbivores is central to co-evolutionary theory. to demonstrate the role of herbivores as selective agents on plant resistance there must be variability in plant resistance to herbivores within a plant population. this variability must be under genetic control, and the variability in plant resistant traits and consequently herbivore damage to plants must reflect variability in plant fitness. we used a common eu ...200228547153
expression of pgk-a in the australian brush-tailed possum, trichosurus vulpecula (kerr), consistent with paternal x inactivation.an extensive survey of erythrocytes of marsupials other than kangaroos for electrophoretic variation if x-linked enzymes revealed two rare pgk-a phenotypes in the phalangerid trichosurus vupecula and one in trichosurus caninus. four putatively heterozygous females expressed only the variant allelic isozyme in some tissues but expressed a trace of the normal isozyme in others. a putatively hemizygous male expressed only the variant isozyme in all tissues. the phenotypic patterns were consistent w ...1979486075
spatial utilization predicts animal social contact networks are not scale-free.while heterogeneity in social behaviour has been described in many human contexts it is often assumed to be less common in the animal kingdom even though scale-free networks are observed. this homogeneity raises the question of whether the patterns of behaviour necessary to account for scale-free social contact networks, where the degree distribution follows a power law, i.e. a few individuals are very highly connected but most have only a few connections, occur in animals, or whether other mech ...201729308252
the response of an arboreal mammal to livestock grazing is habitat dependant.inappropriate livestock grazing is implicated in the decline of vertebrate fauna species globally. faunal responses to grazing can interact with the vegetation community in which they occur. we measured the response of an arboreal marsupial, the common brushtail possum (trichosurus vulpecula vulpecula) to different cattle grazing strategies and vegetation types, and examined whether micro-habitat selection is driving this response. we hypothesised that where arboreal habitat is intact, brushtail ...201729234116
intraspecific variation in nutritional composition affects the leaf age preferences of a mammalian herbivore.ecologists have long been interested in how the nutritional composition of leaves changes as they age, and whether this affects herbivore feeding preferences. as a consequence, the literature abounds with reports that younger leaves contain higher concentrations of nitrogen and plant secondary metabolites (psms) than do older leaves. most of these studies, however, base their conclusions on average values that often mean little to herbivores. we examined this issue in the well-studied marsupial- ...201829209932
livestock as sentinels for an infectious disease in a sympatric or adjacent-living wildlife reservoir host.a central question to address in managing wildlife diseases is how much effort and resources are required to reduce infection prevalence to below a requisite threshold? this requires surveillance for infection in at least one species involved in the infection cycle, a process that is often expensive and time-consuming but one which could be enhanced using additional sources of readily-obtainable surveillance data. we demonstrate how surveillance data from ruminant livestock monitored for bovine ...201729157368
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