Macropus Fuliginosus Research Articles

Dryland Salinity and the Ecology of Ross River Virus: The Ecological Underpinnings of the Potential for Transmission

Alterations in transmission of vector-borne zoonoses are often linked to environmental change. However, ecological processes that determine variability in potential for transmission are generally not well understood. Ross River virus (RRV, Togoviridae: Alphavirus) is a mosquito-borne zoonosis in Australia with a significant human disease burden. The inland southwest (Wheatbelt) of Western Australia (WA) is substantially affected by an anthropogenic salinization of agricultural land (dryland salinity). Aedes camptorhynchus Thomson (Diptera: Culicidae) is the dominant vector of RRV in southwest WA and is halophilic. As such, dryland salinity may influence potential for RRV transmission by influencing interactions between Ae. camptorhynchus and mammalian hosts. We surveyed areas of the Wheatbelt with varying salinity impacts and found Ae. camptorhynchus was more abundant in saline areas, whereas sheep Ovis aries (Linnaeus 1758, Bovidae) declined with increasing salinity. We used a deterministic model to examine interactions between Ae. camptorhynchus and mammals, and we assessed potential for RRV transmission. We found variation in potential for RRV transmission was positively related to increasing salinity and abundance of Ae. camptorhynchus and negatively associated with increasing abundance of Macropus fuliginosus (Desmarest 1817, Macropodidae). Abundance of Ae. camptorhynchus determined more variation in potential for RRV transmission than other variables. Accordingly, dryland salinity increases the zoonotic potential for RRV transmission primarily by facilitating abundance of Ae. camptorhynchus. Human RRV notifications do not currently reflect the salinity-RRV transmission potential in the Wheatbelt but appear to be associated with RRV activity in the enzootic coastal zone. We speculate dryland salinity is a determinant of potential for RRV transmission but not activity. Dryland salinity is predicted to expand two- to four-fold by 2050. Preservation and restoration of freshwater ecosystems may ameliorate the potential for transmission of RRV and possibly incidence of human disease.

Molecular detection of hybridization between sympatric kangaroo species in south-eastern Australia

Introgressive hybridization has traditionally been regarded as rare in many vertebrate groups, including mammals. Despite a propensity to hybridize in captivity, introgression has rarely been reported between wild sympatric macropodid marsupials. Here we investigate sympatric populations of western (Macropus fuliginosus) and eastern (Macropus giganteus) grey kangaroos through 12 autosomal microsatellite loci and 626 bp of the hypervariable mitochondrial DNA (mtDNA) control region. M. fuliginosus and M. giganteus within the region of sympatry corresponded, both genetically and morphologically, to their respective species elsewhere in their distributions. Of the 223 grey kangaroos examined, 7.6% displayed evidence of introgression, although no F1 hybrids were detected. In contrast to captive studies, there was no evidence for unidirectional hybridization in sympatric grey kangaroos. However, a higher portion of M. giganteus backcrosses existed within the sample compared with M. fuliginosus. Hybridization in grey kangaroos is reflective of occasional breakdowns in species boundaries, occurring throughout the region and potentially associated with variable conditions and dramatic reductions in densities. Such rare hybridization events allow populations to incorporate novel diversity while still retaining species integrity.

Landscape discontinuities influence gene flow and genetic structure in a large, vagile Australian mammal,Macropus fuliginosus

Large vagile mammals typically exhibit little genetic structuring across their range, particularly when their habitat is essentially continuous. We investigated the population genetic structure of a large vagile Australian macropodid, Macropus fuliginosus, which is continuously distributed across most of southern Australia, using nine highly polymorphic nuclear microsatellite loci. Five distinct genetic units were identified across the range, four on the mainland and one on Kangaroo Island. In addition to the predicted historic Nullarbor Plain Barrier, two unexpected mainland barriers to gene flow were identified. Both were associated with landscape discontinuities (Swan River, Flinders Ranges), which appear within the dispersal capabilities of M. fuliginosus. Typical of large vagile mammals, M. fuliginosus displays high genetic diversity (with the exception of an insular population) and weak genetic structuring (within genetic units). However, the expansion of M. fuliginosus from southwestern Australia during the Pleistocene has resulted in significantly reduced genetic diversity in eastern populations. No significant sex-biased dispersal was detected, although differences in habitat, densities and climatic conditions between the eastern and western regions of the range appear to influence dispersal with the effects of isolation by distance only evident in the west. These results suggest that the biogeography of southern Australia is more complex than previously thought and reveal that seemingly minor landscape features can significantly impact genetic structuring in large vagile mammals.

Vertical transmission of Toxoplasma gondii in Australian marsupials

To date, little is known about the dynamics of vertical transmission of Toxoplasma gondii in Australian marsupials. Studies in mice demonstrate that vertical transmission of T. gondii is common and that chronically infected mice can transmit T. gondii to successive generations. In this study, PCR and immunohistochemistry were used to detect T. gondii in chronically infected marsupial dams and their offspring. T. gondii was detected in the unfurred pouch young of 2 out of 10 chronically infected western grey kangaroos (Macropus fuliginosus) and in the unfurred pouch young of a brush-tailed bettong (Bettongia penicillata). Results of the study suggest that vertical transmission of T. gondii can occur in chronically infected Australian marsupials.

Morphologic Evidence Suggestive of Hypertension in Western Gray Kangaroos (Macropus fuliginosus)

Marked renal vascular changes, suggestive of hypertension, were present in adult western gray kangaroos (Macropus fuliginosus) from a single facility over a 14-year period. A subset of these kangaroos also had vague clinical nervous system deficits, including blindness. To characterize the vascular lesions, determine prevalence, and document other changes, case histories and archival tissue sections from 21 adult kangaroos (8 male, 13 female) that died or were euthanatized between 1994 and 2008 were reviewed. Relevant lesions included increased thickness of the renal arteriolar tunica media with smooth muscle hypertrophy and/or hyperplasia, accumulation of extracellular matrix within arterioles, increased vascular tortuosity, and varying degrees of juxtaglomerular hyperplasia. Renal tissue from two more severely affected animals was further examined by transmission electron microscopy, highlighting arteriolar endothelial cell hypertrophy and disruption of the medial architecture. Hypertrophy of arteries and arterioles in other organ systems was also present (3/21), including vessels in the brain and spinal cord of one animal with clinical neurologic signs. Four kangaroos had antemortem retinal detachment, a potential sequel of hypertension in humans and domestic mammals. The cause of these vascular lesions in this mob is uncertain. Lesions were not associated with an infectious disease process, age, underlying renal disease, or thyroid abnormalities. In the absence of other causes, hypertension was a differential. Further investigation into clinical significance and predisposing factors, such as genetics and diet, is warranted.

Seroprevalence of Toxoplasma gondii in wild kangaroos using an ELISA

Infection with Toxoplasma gondii is a significant problem in Australian marsupials, and can lead to devastating disease and predispose animals to predation. T. gondii infection in kangaroos is also of public health significance due to the kangaroo meat trade. A moderate seroprevalence of T. gondii was observed in a study of western grey kangaroos located in the Perth metropolitan area in Western Australia. Of 219 kangaroos tested, 15.5% (95%CI: 10.7–20.3) were positive for T. gondii antibodies using an ELISA developed to detect T. gondii IgG in macropod marsupials. When compared with the commercially available MAT (modified agglutination test), the ELISA developed was in absolute agreement and yielded a κ coefficient of 1.00. Of 18 kangaroos tested for the presence of T. gondii DNA by PCR, the 9 ELISA positive kangaroos tested PCR positive and the 9 ELISA negative kangaroos tested PCR negative indicating the ELISA protocol was both highly specific and sensitive and correlated 100% with the more labour intensive PCR assay.

The measurement of luteinising hormone in the western grey kangaroo (Macropus fuliginosus ocydromus) and the black-flanked rock wallaby (Petrogale lateralis lateralis)

An enzyme immunoassay with an anti-bovine-LH antibody (518B7) was applied to female western grey kanagaroos (Macropus fuliginosus ocydromus) and black-flanked rock wallabies (Petrogale lateralis lateralis). Validation showed parallelism to the assay standard curve, and significant increases in plasma LH concentrations after challenging animals with intramuscular GnRH.

Boys will be boys: social affinity among males drives social segregation in western grey kangaroos

AbstractIn many sexually dimorphic and polygynous species, individuals exhibit social segregation by grouping with others of their own sex. Several proximate mechanisms have been proposed to explain social segregation: female avoidance of males, male avoidance of females, avoidance of harassment, male social affinity, female social affinity and activity budget asynchrony. Some of these have been tested in ungulate species, but few previous studies have been able to rigorously test, or distinguish between, these mechanisms because they have failed to examine the fission/fusion dynamics of groups. We tested these proximate mechanisms simultaneously in western grey kangaroos Macropus fuliginosus, by examining whether females, small males or large males instigated segregation by leaving mixed‐sex groups or joining individuals of their own sex or size class. Females, small males and large males left mixed‐sex groups as if leaving were independent of sex–size class. In contrast, large males joined male‐only groups more frequently than expected. These results suggest that the need for males to maintain contact with other males can contribute to the cohesion of male‐only groups and promote segregation. As male–male competition occurs in many polygynous species that sexually segregate, a comparable mechanism might be operating in other taxa, and should be examined further.

Brain thermal inertia, but no evidence for selective brain cooling, in free-ranging western grey kangaroos (Macropus fuliginosus)

Marsupials reportedly can implement selective brain cooling despite lacking a carotid rete. We measured brain (hypothalamic) and carotid arterial blood temperatures every 5 min for 5, 17, and 63 days in spring in three free-living western grey kangaroos. Body temperature was highest during the night, and decreased rapidly early in the morning, reaching a nadir at 10:00. The highest body temperatures recorded occurred sporadically in the afternoon, presumably associated with exercise. Hypothalamic temperature consistently exceeded arterial blood temperature, by an average 0.3 degrees C, except during these afternoon events when hypothalamic temperature lagged behind, and was occasionally lower than, the simultaneous arterial blood temperature. The reversal in temperatures resulted from the thermal inertia of the brain; changes in the brain to arterial blood temperature difference were related to the rate of change of arterial blood temperature on both heating and cooling (P < 0.001 for all three kangaroos). We conclude that these data are not evidence for active selective brain cooling in kangaroos. The effect of thermal inertia on brain temperature is larger than might be expected in the grey kangaroo, a discrepancy that we speculate derives from the unique vascular anatomy of the marsupial brain.

Seroprevalence of Retrovirus in North American Captive Macropodidae

Laboratory records of serology results from captive macropodidae sampled between 1997 and 2005 were reviewed to assess the seroprevalence of retrovirus exposure. Serum samples from 269 individuals (136 males, 133 females) representing 10 species of macropods housed in 31 North American captive collections were analyzed for retrovirus antibody using an indirect immunofluorescent assay. The prevalence of positive antibody titers comparing male versus female, between species, between age groups, and among animals with identified parentage was examined by nonparametric statistical analyses. Median age of animals at time of sample collection was 36 mo (range 2-201 mo). Total percentage seropositive was 20.4%. Serum antibody was detected in 31 of 47 (66.0%) tammar wallaby (Macropus eugenii), nine of 24 (37.5%) yellow-footed rock wallaby (Petrogale xanthopus), four of 11 (36.4%) swamp wallaby (Wallabia bicolor), 10 of 80 (12.5%) red-necked wallaby (Macropus rufogriseus), and one of 54 (1.9%) parma wallaby (Macropus parma). No individuals of western gray kangaroo (n=3) (Macropus fuliginosus), eastern gray kangaroo (n=19) (Macropus giganteus), common wallaroo (n=6) (Macropus robustus), red kangaroo (n=11) (Macropus rufus), or Matschie's tree kangaroo (n=14) (Dendrolagus matschiei) were positive for retrovirus antibody. These results demonstrate that five species of captive macropods have a history of exposure to retrovirus, with the highest percentage seropositive and highest statistical correlation in M. eugenii (pair-wise Fisher's exact test, alpha = 0.05). Additionally, one wild-caught M. eugenii was confirmed seropositive during quarantine period, indicating that retrovirus exposure may exist in wild populations.

Seroepidemiology of Toxoplasma gondii in Zoo Animals in Selected Zoos in the Midwestern United States

Toxoplasma gondii infections in zoo animals are of interest because many captive animals die of clinical toxoplasmosis and because of the potential risk of exposure of children and elderly to T. gondii oocysts excreted by cats in the zoos. Seroprevalence of T. gondii antibodies in wild zoo felids, highly susceptible zoo species, and feral cats from 8 zoos of the midwestern United States was determined by using the modified agglutination test (MAT). A titer of 1:25 was considered indicative of T. gondii exposure. Among wild felids, antibodies to T. gondii were found in 6 (27.3%) of 22 cheetahs (Acynonyx jubatus jubatus), 2 of 4 African lynx (Caracal caracal), 1 of 7 clouded leopards (Neofelis nebulosa), 1 of 5 Pallas cats (Otocolobus manul), 12 (54.5%) of 22 African lions (Panthera leo), 1 of 1 jaguar (Panthera onca), 1 of 1 Amur leopard (Panthera pardus orientalis), 1 of 1 Persian leopard (Panthera pardus saxicolor), 5 (27.8%) of 18 Amur tigers (Panthera tigris altaica), 1 of 4 fishing cats (Prionailurus viverrinus), 3 of 6 pumas (Puma concolor), 2 of 2 Texas pumas (Puma concolor stanleyana), and 5 (35.7%) of 14 snow leopards (Uncia uncia). Antibodies were found in 10 of 34 feral domestic cats (Felis domesticus) trapped in 3 zoos. Toxoplasma gondii oocysts were not found in any of the 78 fecal samples from wild and domestic cats. Among the macropods, antibodies were detected in 1 of 3 Dama wallabies (Macropus eugenii), 1 of 1 western grey kangaroo (Macropus fuliginosus), 1 of 2 wallaroos (Macropus robustus), 6 of 8 Bennett's wallabies (Macropus rufogriseus), 21 (61.8%) of 34 red kangaroos (Macropus rufus), and 1 of 1 dusky pademelon (Thylogale brunii). Among prosimians, antibodies were detected in 1 of 3 blue-eyed black lemurs (Eulemur macaco flavifrons), 1 of 21 ring-tailed lemurs (Lemur catta), 2 of 9 red-ruffed lemurs (Varecia variegata rubra), and 2 of 4 black- and white-ruffed lemurs (Varecia variegata variegata). Among the avian species tested, 2 of 3 bald eagles (Haliaeetus leucocephalus) were seropositive. Among 7 possible risk factors, sex, freezing meat temperature (above -13 C vs. below -13 C), washing vegetables thoroughly, frequency of feral cat sightings on zoo grounds (occasionally vs. frequently), frequency of feral cat control programs, capability of feral cats to enter hay/grain barn, and type of animal exhibit, exhibiting animals in open enclosures was the only factor identified as a significant risk (OR 3.22, P = 0.00).

276. The technical and biological validation of an LH assay for use with the Western Grey Kangaroo (Macropus fuliginosis) and Black-flanked Rock Wallaby (Petrogale lateralis lateralis)

Methods for the measurement of marsupial LH invariably rely upon the similarity of the LH molecule between different species and usually use anti-ovine or anti-bovine LH antibody and an ovine or bovine labelled LH preparation. Initial attempts to measure plasma LH in the Western Grey Kangaroo with assays using antibodies to 4 different isoforms of ovine LH raised in 7 different rabbits were unsuccessful. An enzymeimmunoassay (EIA) developed for the Asian elephant (Zoo Biology 23:45–63) was then applied to the Western Grey Kangaroo and the Black-flanked Rock Wallaby. This EIA has an anti-bovine-LH monoclonal antibody (518B7 provided by Dr Jan Roser, University of California, Davis, USA), biotinylated ovine LH label and bovine LH standard (NIADDK-oLH-26 and NIH-bLH-B10, both provided by Dr Janine Brown and Nicole Abbondanza, Smithsonian Institute, Front Royal, Virginia USA). Technical validation showed that serial dilution down to 1:8 of plasma from 7 individuals of each species showed parallelism to the assay standard curve, and control samples (1.24–5.30 ng/mL) had between-assay coefficients of variation &lt;9%. Biological validation was achieved by challenging animals with intramuscular GnRH (Fertagyl®, 2.5 µg/kg) and measuring LH before and 25 min after the injection. Significant increases in plasma concentrations of LH (mean ± sem; all P &gt; 0.0005) were seen after GnRH for both the Western Grey Kangaroo (from 5.0 ± 0.8 ng/mL to 9.4 ± 1.2 ng/mL; n = 19) and the Black-flanked Rock Wallaby (from 6.0 ± 0.7 ng/mL to 10.6 ± 0.6 ng/mL; n = 28). In conclusion, this assay can be successfully used to measure LH in these two species.

Bothriocroton concolor (Acari: Ixodidae) on the Kangaroo Island Kangaroo: A New Host-Parasite Relationship

In 2006, we examined Kangaroo Island kangaroos, Macropus fuliginosus fuliginosus, for ticks. We collected three tick species: Ixodes hirsti Hassall, Hemaphysalis bancrofti Nuttall & Warburton, and Bothriocroton concolor (Neumann). Surprisingly, the specimens included eight females and one nymph of B. concolor, which had previously been considered strictly host specific to the echidna (Tachyglossus sp.). This is the first record of B. concolor on the Kangaroo Island kangaroo.

Spatial patterns of kangaroo density across the South Australian pastoral zone over 26 years: aggregation during drought and suggestions of long distance movement

Summary Wildlife surveys usually focus on estimating population size, and management actions such as commercial harvesting, culling and poison baiting are referenced commonly to population size alone, without taking into account the way in which those animals are distributed. This paper outlines how point‐based aerial survey data can be converted to continuous density surfaces using spatial analysis techniques. Using this approach, we describe and explore the spatial patterns of density of two species of kangaroos in an area exceeding 200 000 km2 in South Australia over a 26‐year period. Densities of red and western grey kangaroos were estimated in 2 km2 segments along aerial survey transect lines, yielding point density estimates. Universal kriging provided an unbiased interpolation of these data using the spatial autocorrelation structure described by the semi‐variogram. The Getis statistic identified clusters of high and low kangaroo density. Considerable year‐to‐year variation in the spatial patterns of kangaroo density was observed. In many cases, annual rates of increase over large areas were too high to be explained by vital rates alone, implying immigration from surrounding areas. These large shifts in distribution were occasionally to areas that had received better rainfall than the surrounding areas. For both species, there was no obvious local spatial autocorrelation pattern or clustering of kangaroo density beyond that described by average density and the present set of management regions, suggesting the latter are appropriate divisions for harvest management. Data for both species fitted the power law relationship extremely well. During dry times, red kangaroos, but not western grey kangaroos, were more aggregated, supporting past ground observations at a fine spatial scale. Synthesis and applications. Kriged density surfaces enable estimation of kangaroo density on individual properties, which are the management units at which harvest quotas or culling approvals are allocated. These estimates will be marked improvements over systematic sampling estimates when sampling intensity is low. Predictions of shifts in kangaroo distribution using rainfall or satellite imagery will allow more accurate allocation of harvest quotas. Similarly, predictions of more even kangaroo dispersion following high rainfall will allow managers to anticipate downturns in harvest rate.

Sexual segregation in western grey kangaroos: testing alternative evolutionary hypotheses

AbstractIn sexually dimorphic ungulates, sexual segregation is hypothesized to have evolved because of sex‐specific differences in body size and/or reproductive strategies. We tested these alternative hypotheses in kangaroos, which are ecological analogues of ungulates. Kangaroos exhibit a wide range of body sizes, particularly among mature males, and so the effects of body size and sex can be distinguished. We tested predictions derived from these hypotheses by comparing the distribution of three sex–sex size classes of western grey kangaroos Macropus fuliginosus, in different habitats, and the composition of groups of kangaroos, across seasons. In accordance with the predation risk‐reproductive strategy hypothesis, during the non‐breeding season, females, which were more susceptible to predation than larger males, and were accompanied by vulnerable young‐at‐foot, were over‐represented in secure habitats. Large males, which were essentially immune to predation, occurred more often than expected in nutrient‐rich habitat, and small males, which faced competing demands of predator avoidance and feeding, were intermediate between females and large males in their distribution across habitats. During the breeding season, females continued to be over‐represented in secure habitats when their newly emerged pouch young were most vulnerable to predation. All males occupied these same habitats to maximize their chances of securing mates. Consistent with the social hypotheses, groups composed of individuals of the same sex, irrespective of body size, were over‐represented in the population during the non‐breeding season, while during the breeding season all males sought females so that mixed‐sex groups predominated. These results indicate that body size and reproductive strategies are both important, yet independent, factors influencing segregation in western grey kangaroos.

Hosts of the exotic ornate kangaroo tick, Amblyomma triguttatum triguttatum Koch, on southern Yorke Peninsula, South Australia

Amblyomma triguttatum triguttatum is assumed to be endemic to south-western Western Australia (including Barrow Island), Queensland (excluding Cape York Peninsula), and New South Wales, south to Dubbo and Barham. The species has been recorded on a range of mammalian hosts including macropods and domestic animals. In Queensland, A. triguttatum triguttatum is implicated in the epidemiology of Q fever. In 2000, the species was detected on southern Yorke Peninsula in South Australia. We aimed to identify A. triguttatum triguttatum's hosts through trapping, sampling of carcasses, and opportunistic capture of vertebrates on Yorke Peninsula. A. triguttatum triguttatum was removed from black rats (Rattus rattus), wild rabbits (Oryctolagus cuniculus), western grey kangaroos (Macropus fuliginosus), Tammar wallabies (M. eugenii eugenii), domesticated cats and dogs, and humans. Before this study, A. triguttatum triguttatum had not been found on black rats or rabbits in the wild. This research has implications for the management of wildlife, livestock, and visitors on Yorke Peninsula. The potential for A. triguttatum triguttatum to spread to other areas of Yorke Peninsula and South Australia is considerable, as visitors (tourists) to southern Yorke Peninsula report the presence of ticks both on themselves and among camping equipment on arriving home.

Effects of Novel and Historic Predator Urines on Semi‐Wild Western Grey Kangaroos

Abstract: Classic studies in fear ecology have been inconclusive regarding whether predator waste products repel herbivores and whether the deterrent effect, if any, is based on repulsion or fear. Other studies imply that the predator must have co‐evolved with prey to maximize the efficacy of response. We used chemosensory cues from the urine of native and nonnative canines to manipulate the behavior of the western grey kangaroo (Macropus fuliginosus). One‐choice feeding trials were located along a distance gradient, and administered to 28 free‐ranging, semi‐wild, western grey kangaroos. Foods closer to the chemical source (within 12 m) were less likely to be eaten than those further from the source when the urine came from a native predator, the dingo (Canis dingo). Flight behavior was more likely to be observed on occasions when the dingo urine had been presented. A lesser effect occurred (to within 6 m) when urine was presented from the nonnative canid (coyote [Canis latrans]), while the flight behavior occurred once. Neither human urine, nor tap‐water control, had any effect. We offer the first evidence that native predator‐based chemical cues affect patch selection, while increasing fear, for this herbivore.

The distribution and dispersion of Amblyomma triguttatum triguttatum on Yorke Peninsula, South Australia

The kangaroo tick, Amblyomma triguttatum triguttatum, is a major enzootic vector of Coxiella burnetti, the agent causing Q fever, in Australia. This is a widespread tick species previously reported from Queensland, New South Wales and Western Australia. There is also a small population, probably introduced, at the foot of Yorke Peninsula in South Australia. Our aim was to determine both the broad distribution of this tick on Yorke Peninsula and the pattern of dispersion between habitats. No free living A. t. triguttatum were found outside of Innes and Warrenben national parks, although records from humans are available from up to 180 km away. Within the parks, the tick is patchily spread in at least 8 of the 15 habitats searched but is most common in the disturbed areas in and around camping sites. We suggest that the behaviour of the tick’s main host, the western grey kangaroo, Macropus fuliginosus, is responsible for its dispersion pattern.

Description of Three New Species of Theileria Bettencourt, Franca & Borges, 1907 From Macropodoidea in Western Australia

SummaryWe describe three novel species of piroplasms, each from a distinct host species within the Macropodoidea, in Western Australia; namely, Setonix brachyurus (Quoy & Gaimard, 1830), Macropus fuliginosus (Desmarest, 1817) (Macropodidae) and Bettongia penicillata (Gray, 1837) (Potoroidae). The light-microscopic appearance of organisms in blood films was typical of the Piroplasmida. Phylogenetic analyses of partial 18S rRNA gene sequences revealed that isolates from three marsupial species form reciprocally monophyletic clades within the Theileriidae, and each have a relatively high level of divergence (3.6 to 7.4%) from each other. The distinct molecular differences indicate these organisms should be regarded as separate, novel species which we designate Theileria brachyuri sp. nov., Theileria fuliginosa sp. nov., and Theileria penicillata sp. nov.

Effects of temperature and duration of sample storage on the haematological characteristics of western grey kangaroos (Macropus fuliginosus)

To investigate the effects of storage duration and temperature on haematological analyses performed on blood from the western grey kangaroo (Macropus fuliginosis). Blood samples from five western grey kangaroos were stored at 4 degrees C, 24 degrees C and 36 degrees C. Each sample was analysed haematologically over a 5-day period. The blood samples maintained optimal stability at 4 degrees C. At this temperature the haematological values remained essentially unchanged for the duration of the study, while samples stored at 36 degrees C and 24 degrees C showed significant changes in some haematological measures by 12 h and 48 h, respectively. Disturbances in leukocyte morphology were evident, to varying degrees, in all samples. Blood samples from macropodids should be tested within 48 h of collection if stored at a room temperature of about 24 degrees C. Where testing is to be delayed for more than 48 h, samples should be refrigerated as soon as possible. Exposure of samples to heat in excess of 24 degrees C should be avoided at all times.