Articoli di riviste: "Australian marsupials"

1

J. Foley, William. "Marsupial Nutrition". Pacific Conservation Biology 5, n. 3 (1999): 240. http://dx.doi.org/10.1071/pc99240a.

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In the early 1980s advances in marsupial biology could no longer be encapsulated in a single volume such as Hugh Tyndale-Biscoe's "Life of Marsupials" and Cambridge University Press commissioned a series of monographs covering a range of different topics in marsupial biology. As it was, only three of that series were realized and among them was the ptedecessor to this book "Digestive Physiology and Nutrition of Marsupials" published in 1982. "Marsupial Nutrition" is a considerably expanded and comprehensive review of studies of nutrition and digestive physiology of Australasian and South American marsupials. In Australia, many ecologists view the limited nutrient status of our soils and vegetation as a fundamental limit to animal populations. This book explains firstly how Australian marsupials have responded to those limitations and secondly asks whether these responses are common amongst marsupials living in New Guinea and South America.

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Kirsch, John A. W., Mark S. Springer e François-Joseph Lapointe. "DNA-hybridisation Studies of Marsupials and their Implications for Metatherian Classification". Australian Journal of Zoology 45, n. 3 (1997): 211. http://dx.doi.org/10.1071/zo96030.

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We review past DNA-hybridisation studies of marsupials and present a reanalysis of the data, utilising results from our and additional studies to formulate and rationalise a new classification of Marsupialia. In the reanalysis, 13 individual DNA-hybridisation matrices, many lacking some pairwise comparisons, were sutured in stages to provide the basis for generating a tree of 101 marsupials plus an outgroup eutherian; a fourteenth matrix provided data for a tree including eight additional eutherians and a monotreme. Validation was achieved by jackknifing on taxa for each matrix as well as on tables combining two or more matrices generated during assembly of the 102-taxon data set. The results are consistent with most conclusions from the individual studies and dramatise the unevenness of hierarchical levels in current classifications of marsupials. In particular, the affinities of the American marsupial Dromiciops gliroides with, and the distinctness of marsupial bandicoots from, Australasian metatherians are reaffirmed, while opossums are shown to be as internally divergent as are most members of the order Diprotodontia. Calibration of the 102-taxon tree and dating of the major dichotomies suggest that no extant marsupial lineage originated before the latest Cretaceous, and that all of them together with most South American and all Australasian fossils should be recognised as a monophyletic group contrasting with a largely Laurasian (if possibly paraphyletic) taxon. These inferences, together with the details of the phylogeny, mandate that the misleading ‘Australian’ v. ‘American’ distinction be abandoned, even as a geographic convenience.

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Burke, Catherine, Delaney Burnard, Adam Polkinghorne, Jonathan Webb e Wilhelmina Huston. "Cloacal and Ocular Microbiota of the Endangered Australian Northern Quoll". Microorganisms 6, n. 3 (12 luglio 2018): 68. http://dx.doi.org/10.3390/microorganisms6030068.

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The Australian northern quoll is an important predatory marsupial carnivore that is currently endangered due to inappropriate fire regimes, predation, and the spread of invasive cane toads. The microbiota of Australian marsupials has not been extensively studied, but is thought to play a role in their health. This study provides an initial characterization of the cloacal microbiota of the northern quoll, as well as other marsupials including possums and kangaroos which were opportunistically sampled. The northern quoll cloaca microbiota was dominated by Enterococcus and Lactobacillus and had a relatively high proportion of members of the Proteobacteria phylum, which has been observed in other carnivorous marsupials. The diversity and structure of the microbiota was not influenced by presence of Chlamydiales which are intracellular bacteria and potential pathogens. The microbiota of the other marsupials was quite varied, which may be related to their health status. Characterization of the northern quoll microbiota will help to better understand the biology of this endangered animal.

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4

PARAMESWARAN, N., R. M. O'HANDLEY, M. E. GRIGG, A. WAYNE e R. C. A. THOMPSON. "Vertical transmission of Toxoplasma gondii in Australian marsupials". Parasitology 136, n. 9 (24 giugno 2009): 939–44. http://dx.doi.org/10.1017/s0031182009006453.

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SUMMARYTo 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.

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Snipes, RL, H. Snipes e FN Carrick. "Morphometric data on the intestines of five Australian marsupials (Marsupialia)." Australian Mammalogy 25, n. 2 (2003): 193. http://dx.doi.org/10.1071/am03193.

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THE nutritional biology of marsupials has been a subject of numerous studies, culminating in valuable compilations covering a wide range of aspects (Osman Hill and Rewell 1954; Walton and Richardson 1989; Hume 1982, 1999; Kerle 2001). Despite this thorough coverage, there remains a scarcity of morphometric data on the intestines of monotremes and marsupials. In an attempt to approach this need, an effort was initiated to provide morphometric data on monotremes (Snipes et al. 2002) and marsupials (Snipes et al. 1993, 2003).

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6

Harman, AM. "The Optic Chiasm of Australian Marsupials". Australian Journal of Zoology 43, n. 5 (1995): 467. http://dx.doi.org/10.1071/zo9950467.

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The optic chiasm of mammals is the region of the nervous system in which optic axons have a choice of route, either they enter the optic tract on the same side of the brain or they cross the chiasm and enter the opposite optic tract. in eutherian (placental) mammals, axons approach the midline of the chiasm and then either continue across the chiasm or turn back to enter the tract on the same side of the brain. The midline of the chiasm provides guidance cues that repel uncrossed but not crossed axons. However, it has recently been shown that in a marsupial, the quokka wallaby, axons destined to stay on the same side of the brain remain in the lateral part of the optic nerve and chiasm and never approach the midline. The structure of the chiasm reflects this partitioning of axons with different routes by having a tripartite structure. The two lateral regions contain only uncrossed axons in rostral chiasmatic regions and the central region contains only crossed axons. Therefore, axons passing through the chiasm of this species must use guidance cues that differ from those of eutherian mammals. Here I show that the chiasms of species of both diprotodont and polyprotodont Australian marsupials have a similar tripartite structure and that uncrossed axons are confined to lateral regions. It seems likely, therefore, that the chiasm of marsupials has fundamental differences in structure and optic axon trajectory compared with that of eutherian mammals studied to date.

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7

Riley, J., DM Spratt e PJA Presidente. "Pentastomids (Arthropoda) Parasitic in Australian Reptiles and Mammals." Australian Journal of Zoology 33, n. 1 (1985): 39. http://dx.doi.org/10.1071/zo9850039.

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Records of pentastomid arthropods parasitic in Australian reptiles and mammals are reviewed, with particular reference to material collected recently. Specimens representative of six genera are described. Sebekia sp. from the estuarine crocodile, Crocodylusporosus, is the first record of the genus in Australia and probably represents a new species. A nymph with double hooks, from the dasyurid marsupial Satanellus hallucatus, is determined as Waddycephalus sp. This represents the first evidence of double hooks in nymphal forms of the genus and of the role of marsupials as intermediate hosts of Waddycephalus. Nymphs from the peramelid marsupial, Isoodon macrourus, and from S, hallucatus are determined as Armillifer australis Riley & Self, 1981; those from Perameles nasuta are identified as A. arborealis Riley & Self, 1981. These represent the first records of marsupials as intermediate hosts of Armillifer. Adults of the genus Elenia Heymons, 1932 are confirmed as parasites of varanid lizards. E. australis Heymons, 1932 is recognized and it is suggested that specimens described by Heymons (1939), allegedly from Varanus varius at Townsville, Qld, may represent a new species. The cosmopolitan porocephalid Linguatula serrata Frolich, 1789 is recorded from the nasopharynx of the dingo or wild dog and the validity of the indigenous species, L. dingophila Johnson, 1910 is discussed. The cephalobaenid Raillietiella amphiboluri Mahon, 1954 is reported from Amphibolurus barbatus.

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8

Beveridge, Ian. "Parasites of Australian marsupials". British Veterinary Journal 144, n. 3 (maggio 1988): 211–12. http://dx.doi.org/10.1016/0007-1935(88)90103-0.

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9

Arrese, Catherine A., Nathan S. Hart, Nicole Thomas, Lyn D. Beazley e Julia Shand. "Trichromacy in Australian Marsupials". Current Biology 12, n. 8 (aprile 2002): 657–60. http://dx.doi.org/10.1016/s0960-9822(02)00772-8.

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10

SPRATT, DAVID M. "Description of capillariid nematodes (Trichinelloidea: Capillariidae) parasitic in Australian marsupials and rodents". Zootaxa 1348, n. 1 (30 ottobre 2006): 1. http://dx.doi.org/10.11646/zootaxa.1348.1.1.

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Capillariid nematodes (Trichinelloidea: Capillariidae) parasitic in Australian dasyurid, peramelid and potoroid marsupials and murid rodents are described. Diagnosis of the genus Eucoleus and a key to species are given. Two species are redescribed: E. gastricus (Baylis) and E. rickardi (Beveridge and Barker), comb. nov. Nine species are described as new: E. breviductus sp. nov., E. buckenbourensis sp. nov., E. fluvidus sp. nov., E. longiductus sp. nov., E. parvulus sp. nov., E. perplexus sp. nov., E. plumosus sp. nov., E. posterus sp. nov. and E. pseudoplumosus sp. nov. Three additional species are recognized but not named. Species of Eucoleus occur in a diverse range of epithelial tissue habitats in Australian hosts throughout eastern Australia; one species is known from peramelids in Western Australia. Members of the genus have not been found in any other families of Australian marsupials. Three species are parasites of dasyurids, eight species are parasites of peramelids, two species occur in both dasyurid and peramelid hosts and two species are parasites of murid rodents. Morphologically, species of Eucoleus appear to be reasonably host specific at the family level. Molecular evidence indicates that sibling species of Eucoleus occur in distinct but closely related host species. Baruscapillaria conspecta sp. nov. is described from murid rodents and the potoroid marsupial rufous rat kangaroo, Aepyprymnus rufescens, primarily in north Queensland. Capillaria ornamentata sp. nov. is described from the distal nasal sinus behind the orbit of the eye of species of dasyurids of the genus Antechinus in southeastern Australia. Aonchotheca praeputialis (Obendorf, 1979) comb. nov. is redescribed and appears to occur exclusively in the native Rattus fuscipes. New host and geographic records, and tissue localities of the trichurid nematode, Anatrichosoma haycocki (Trichinelloidea: Trichuridae, Trichosomoidinae) are given.

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11

Rodger, JC. "Prefertilization gamete maturation events in marsupials". Reproduction, Fertility and Development 6, n. 4 (1994): 473. http://dx.doi.org/10.1071/rd9940473.

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Despite many fundamental similarities between the gametes of marsupials and placental mammals, the regulation and timing of prefertilization gamete maturation are quite different. The marsupial acrosome is remarkably stable and an acrosome reaction (AR) is not induced by reagent effective for the sperm of placental mammals. The ultrastructure of the marsupial sperm AR is essentially similar to that of placental mammals, however, whether an equatorial segment (ES) persists to serve as the site of sperm-egg membrane fusion is unclear. Diacylglycerol induction of the AR suggests that the sperm of Australian species lack an ES, yet an ES-like region appears to be involved in fertilization in the opossum Monodelphis. The marsupial oocyte, unlike those of placentals, continues to grow throughout follicular life and major cytoplasmic maturation events occur late in oocyte development. Cortical granules only become evident shortly before ovulation and mature dark granules may only appear after ovulation. Further, the zona pellucida (ZP) changes in character and function during the peri-ovulatory period. In vitro fertilization has been achieved for an opossum but not for any Australian marsupial, owing to failure of sperm-ZP binding. Requirement for a sperm maturation process is likely, but capacitation treatments used for placental sperm in vitro have been ineffective. Since it is now feasible to experimentally manipulate marsupial gametes in vitro major advances in our understanding of their function can be expected.

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12

Tyndale-Biscoe, Hugh, e Jennifer A. Marshall Graves. "Geoffrey Bruce Sharman 1925–2015". Historical Records of Australian Science 28, n. 2 (2017): 183. http://dx.doi.org/10.1071/hr17011.

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Geoff Sharman was one of the most important figures in the post-war renaissance of research into the indigenous mammals of Australia. He discovered the remarkable phenomenon of delayed development, or embryonic diapause, in kangaroos. He pioneered marsupial cytogenetics, making seminal contributions to chromosome evolution, sex determination, and X chromosome dosage compensation in female marsupials. He inspired a whole generation of younger biologists to make the investigation of Australian mammals the primary objective of their professional careers. Fifty years before he began there had been a brief but highly fruitful period of investigation into the native fauna based at the University of Sydney Medical School.1 When the four pioneers departed to Chairs in Britain and Fellowship of the Royal Society, further research in the field languished until the 1950s. Sharman's research built on that pioneering work, particularly of J. P. Hill and his associates on the reproductive anatomy and development of marsupials, and then extended it into the new field of cytogenetics.

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13

Robinson, ES, MB Renfree, RV Short e JL VandeBerg. "Mammary glands in male marsupials. 2. Development of teat primordia in Didelphis virginiana and Monodelphis domestica". Reproduction, Fertility and Development 3, n. 3 (1991): 295. http://dx.doi.org/10.1071/rd9910295.

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Young and adults of both sexes of two didelphid marsupials, Didelphis virginiana and Monodelphis domestica, were examined externally for evidence of mammary gland development. Female young possessed teat numbers typical of adult females (13-15 in D. virginiana; 11-13 in M. domestica). Male young showed variable teat numbers which were always low compared with females, with the majority possessing 2-4 in anterior positions. Teats were also present in adult males of both species, in similar numbers and locations to those of young males. There are no previous reports of the presence of teats in any adult male marsupials. No mammary primordia in males have been recorded at any stage of development in the most thoroughly studied Australian marsupials. Our findings strengthen the view that there is a dichotomy between the two marsupial lineages in the regulation of male mammary gland expression.

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Stupans, I., B. Jones e R. A. McKinnon. "Xenobiotic metabolism in Australian marsupials". Comparative Biochemistry and Physiology Part C: Toxicology & Pharmacology 128, n. 3 (marzo 2001): 367–76. http://dx.doi.org/10.1016/s1532-0456(00)00211-8.

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15

George, GG. "Monotreme and Marsupial Breeding Programs in Australian Zoos". Australian Journal of Zoology 37, n. 3 (1989): 181. http://dx.doi.org/10.1071/zo9890181.

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Cooperative breeding programs for selected species in Australian zoos have developed rather rapidly in response to growing concerns for the status of wildlife world-wide. The need to enlarge captive populations and to manage them for genetic and demographic stability led in 1983 to the establishment of a regional Species Management Scheme among the major publicly funded zoos of Australia and New Zealand. Several Australian marsupials are being successfully managed under this scheme, and management plans for others are being developed. Managed species are designated on the basis of their restricted availability to zoos, and the desirability of having a self-sustaining captive population for conservation purposes. Captive breeding histories of most Australian and some New Guinea monotremes and marsupials are reviewed, and details of zoo breeding programs discussed for managed species.

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Irlbeck, NA, e ID Hume. "The role of Acacia in the diets of Australian marsupials ? A review." Australian Mammalogy 25, n. 2 (2003): 121. http://dx.doi.org/10.1071/am03121.

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Many of the 600 species of Acacia found in Australia form part of the diet of several groups of marsupials. Acacia foliage is generally high in tannins but is consumed by several folivorous possums and by some macropods (kangaroos and wallabies), but the macropods eat it mainly as dry leaf litter during times of food shortage (in dry seasons and drought). Acacia gum is an important diet component of two omnivorous possums (Petaurus breviceps, Gymnobelidius leadbeateri) and, to a lesser extent, two rat-kangaroos (Bettongia sp.). Acacia seeds are consumed by marsupials to a limited extent, but are an important seasonal component of the diet of the mountain brushtail possum (Trichosurus cunninghami), and possibly the tammar wallaby (Macropus eugenii) on Kangaroo Island. Likewise, Acacia arils (lipid-rich appendages to the seeds of some species) are an important seasonal component of the diet of the mahogany glider (Petaurus gracilis). Acacia pollen and nectar are consumed by several omnivorous possums (e.g., Petaurus norfolcensis) as well as by at least one species of rock-wallaby (Petrogale sp.), but the quantitative contributions made by these floral products to the protein and energy budgets of the consumers have been difficult to determine. Thus several parts of the Acacia plant are food resources for one or more groups of marsupials, but the contribution of the genus to marsupial nutrition is often overlooked.

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Young, Lauren J., Jessica Gurr, Katrina Morris, Sabine Flenady e Katherine Belov. "Molecular characterisation of Interleukin-2 in two Australian marsupials (the tammar wallaby, Notamacropus eugenii, and the Tasmanian devil, Sarcophilus harrisii) facilitates the development of marsupial-specific immunological reagents". Australian Mammalogy 41, n. 1 (2019): 39. http://dx.doi.org/10.1071/am17027.

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Interleukin-2 (IL-2) is an important regulator of cellular immunity in mammals. For many years, our inability to identify the expression of this cytokine in marsupials hindered our capacity to progress studies in metatherian immunology. Here, we report the use of molecular techniques to characterise the IL-2 gene for the tammar wallaby (Notamacropus eugenii) and the Tasmanian devil (Sarcophilus harrisii), which allowed the prediction of the structure and probable functions of the IL-2 proteins of these species. Deduced marsupial IL-2 proteins show considerable sequence identity to each other and to common brushtail possum (Trichosurus vulpecula) IL-2 (≥65%) but shared only 35% (tammar wallaby) and 32% (Tasmanian devil) identity with human IL-2. This difference means that reagents used to study IL-2 in human and other eutherians are unlikely to cross-react with marsupials. As a key step in furthering our ability to study cellular immune responses in marsupials and, more specifically, the susceptibility of macropodoid marsupials to intracellular pathogens, a polyclonal antibody was designed for the detection and future investigation of tammar wallaby IL-2 protein expression. The molecular data and polyclonal antibody described herein will support our development of gene probes and immunological reagents that will aid studies of infection and disease in marsupials.

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18

Jastroch, M., K. W. Withers, S. Taudien, P. B. Frappell, M. Helwig, T. Fromme, V. Hirschberg et al. "Marsupial uncoupling protein 1 sheds light on the evolution of mammalian nonshivering thermogenesis". Physiological Genomics 32, n. 2 (gennaio 2008): 161–69. http://dx.doi.org/10.1152/physiolgenomics.00183.2007.

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Brown adipose tissue expressing uncoupling protein 1 (UCP1) is responsible for adaptive nonshivering thermogenesis giving eutherian mammals crucial advantage to survive the cold. The emergence of this thermogenic organ during mammalian evolution remained unknown as the identification of UCP1 in marsupials failed so far. Here, we unequivocally identify the marsupial UCP1 ortholog in a genomic library of Monodelphis domestica. In South American and Australian marsupials, UCP1 is exclusively expressed in distinct adipose tissue sites and appears to be recruited by cold exposure in the smallest species under investigation ( Sminthopsis crassicaudata). Our data suggest that an archetypal brown adipose tissue was present at least 150 million yr ago allowing early mammals to produce endogenous heat in the cold, without dependence on shivering and locomotor activity.

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Baverstock, PR, M. Krieg e J. Birrell. "Evolutionary Relationships of Australian Marsupials as Assessed by Albumin Immunology". Australian Journal of Zoology 37, n. 3 (1989): 273. http://dx.doi.org/10.1071/zo9890273.

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Current phylogenetic hypotheses of the relationships of Australian marsupials were tested by microcomplement fixation of albumin. The study involved antisera to albumins of 56 species, and cross- reactions to albumins of 199 species. The most notable and controversial features of the study were as follows. (1) Two major lineages are evident among the Australian marsupials- bandicoots-dasyuroids and diprotodontids; the marsupial mole represents a third lineage. (2) The honey possum Tarsipes is clearly a diprotodontid. (3) Acrobates and Distoechurus are monophyletic, but they are not burramyids; they are closely related to Tarsipes; moreover the Acrobates-Distoechurus-Tarsipes clade may be close to petaurids. (4) The New Guinean species of Antechinus are more closely related to the New Guinean Murexia than to Australian species of Antechinus. (5) The bandicoots fall into two groups-the New Guinean genera and the Australian genera; the bilby, Macrotis lagotis, is not clearly distinct from the bandicoots, and may be monophyletic with the New Guinean genera. (6) The banded hare-wallaby Lagostrophus is clearly the sister-group to all other extant macropodines, and may be monophyletic with potoroines rather than macropodines. (7) The genus Macropus may be paraphyletic. (8) The tree-kangaroos Dendrolagus may be closely related to the rock-wallabies and their allies (Petrogale, Peradorcas and Thylogale). (9) The genus Pseudocheirus (ringtail possums) is paraphyletic and its species are highly divergent at the molecular level. (10) The cuscuses (genus Phalanger) are probably a monophyletic assemblage.

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Westerman, M., e D. Edwards. "The Relationship of Dromiciops-Australis to Other Marsupials - Data From Dna Dna Hybridization Studies". Australian Journal of Zoology 39, n. 1 (1991): 123. http://dx.doi.org/10.1071/zo9910123.

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DNA-DNA hybridisations have been used to assess the relationship between the microbiothere, Dromiciops australis, and some South American and Australian marsupials. Although there is support for inclusion of D. australis in a separate superfamily and a slightly closer relationship with the two Australian species used, the data are perhaps best interpreted as showing a trichotomy of divergence between microbiotheres, didelphids and Australian marsupials (dasyurids and macropodids) in the early to mid-Cretaceous.

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Canfield, P. J., W. J. Hartley e J. P. Dubey. "Lesions of toxoplasmosis in Australian marsupials". Journal of Comparative Pathology 103, n. 2 (agosto 1990): 159–67. http://dx.doi.org/10.1016/s0021-9975(08)80172-7.

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Cedillo, C., I. C. Rangel, D. Espinosa, G. Salas, C. P. Rico, O. López, M. Díaz e D. Correa. "Toxoplasmosis in Australian Marsupials in Captivity". Journal of Comparative Pathology 148, n. 1 (gennaio 2013): 87. http://dx.doi.org/10.1016/j.jcpa.2012.11.167.

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Anderson, S., e LF Marcus. "Aerography of Australian Tetrapods". Australian Journal of Zoology 40, n. 6 (1992): 627. http://dx.doi.org/10.1071/zo9920627.

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The sizes of geographic ranges of species of Australian tetrapod groups form 'hollow curve' frequency distributions, with most species having small ranges. Geometric means for range size (in 10(5) km2 units) are 1.2 for frogs and toads, 1.7 for turtles, 2.2 for lizards, 3.2 for snakes, 6.6 for birds, 2.6 for marsupials, 5.1 for bats and 2.1 for rodents. Species' densities are compared for different groups. A map of superimposed species boundaries for mammals demonstrates some relatively homogeneous faunal areas separated by distinct and narrow faunal boundaries but this is not the general pattern. The principal axes of species ranges for many groups are oriented parallel to and near coasts. Species centred on the interior tend to have larger ranges. Estimates or measurements of range size tend to be better if there are more published records, specimens, known localities of occurrence, and ecological data. Australia, in proportion to its area, has more anurans, lizards (and other reptiles), and marsupials, and it has fewer rodents and bats than North America. The ranking of groups for mean range size is the same in both continents except that Anura have smaller ranges than lizards in Australia.

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Moros-Nicolás, Carla, Pascale Chevret, María José Izquierdo-Rico, William V. Holt, Daniela Esteban-Díaz, Manel López-Béjar, Eva Martínez-Nevado, Maria A. Nilsson, José Ballesta e Manuel Avilés. "Composition of marsupial zona pellucida: a molecular and phylogenetic approach". Reproduction, Fertility and Development 30, n. 5 (2018): 721. http://dx.doi.org/10.1071/rd16519.

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The zona pellucida (ZP) is an extracellular matrix that surrounds mammalian oocytes. In eutherians it is formed from three or four proteins (ZP1, ZP2, ZP3, ZP4). In the few marsupials that have been studied, however, only three of these have been characterised (ZP2, ZP3, ZP4). Nevertheless, the composition in marsupials may be more complex, since a duplication of the ZP3 gene was recently described in one species. The aim of this work was to elucidate the ZP composition in marsupials and relate it to the evolution of the ZP gene family. For that, an in silico and molecular analysis was undertaken, focusing on two South American species (gray short-tailed opossum and common opossum) and five Australian species (brushtail possum, koala, Bennett’s wallaby, Tammar wallaby and Tasmanian devil). This analysis identified the presence of ZP1 mRNA and mRNA from two or three paralogues of ZP3 in marsupials. Furthermore, evidence for ZP1 and ZP4 pseudogenes in the South American subfamily Didelphinae and for ZP3 pseudogenes in two marsupials is provided. In conclusion, two different composition models are proposed for marsupials: a model with four proteins (ZP1, ZP2 and ZP3 (two copies)) for the South American species and a model with six proteins (ZP1, ZP2, ZP3 (three copies) and ZP4) for the Australasian species.

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Krige, Anna-Sheree, R. C. Andrew Thompson, Anke Seidlitz, Sarah Keatley, Julia Wayne e Peta L. Clode. "Molecular Detection of Trypanosoma spp. in Questing and Feeding Ticks (Ixodidae) Collected from an Endemic Region of South-West Australia". Pathogens 10, n. 8 (16 agosto 2021): 1037. http://dx.doi.org/10.3390/pathogens10081037.

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A growing number of indigenous trypanosomes have been reported to naturally infect a variety of Australian wildlife with some species of Trypanosoma implicated in the population decline of critically endangered marsupials. However, the mode of transmission of Australian trypanosomes is unknown since their vectors remain unidentified. Here we aimed to fill this current knowledge gap about the occurrence and identity of indigenous trypanosomes in Australian invertebrates by conducting molecular screening for the presence of Trypanosoma spp. in native ticks collected from south-west Australia. A total of 231 ticks (148 collected from vegetation and 83 retrieved directly from 76 marsupial hosts) were screened for Trypanosoma using a High-Resolution Melt (HRM) qPCR assay. An overall Trypanosoma qPCR positivity of 37% (46/125) and 34% (26/76) was detected in questing ticks and host-collected (i.e., feeding) ticks, respectively. Of these, sequencing revealed 28% (35/125) of questing and 28% (21/76) of feeding ticks were infected with one or more of the five species of trypanosome previously reported in this region (T. copemani, T. noyesi, T. vegrandis, T. gilletti, Trypanosoma sp. ANU2). This work has confirmed that Australian ticks are capable of harbouring several species of indigenous trypanosome and likely serve as their vectors.

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Johnson, Christopher N., Joanne L. Isaac e Diana O. Fisher. "Rarity of a top predator triggers continent-wide collapse of mammal prey: dingoes and marsupials in Australia". Proceedings of the Royal Society B: Biological Sciences 274, n. 1608 (31 ottobre 2006): 341–46. http://dx.doi.org/10.1098/rspb.2006.3711.

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Top predators in terrestrial ecosystems may limit populations of smaller predators that could otherwise become over abundant and cause declines and extinctions of some prey. It is therefore possible that top predators indirectly protect many species of prey from excessive predation. This effect has been demonstrated in some small-scale studies, but it is not known how general or important it is in maintaining prey biodiversity. During the last 150 years, Australia has suffered the world's highest rate of mammal decline and extinction, and most evidence points to introduced mid-sized predators (the red fox and the feral cat) as the cause. Here, we test the idea that the decline of Australia's largest native predator, the dingo, played a role in these extinctions. Dingoes were persecuted from the beginning of European settlement in Australia and have been eliminated or made rare over large parts of the continent. We show a strong positive relationship between the survival of marsupials and the geographical overlap with high-density dingo populations. Our results suggest that the rarity of dingoes was a critical factor which allowed smaller predators to overwhelm marsupial prey, triggering extinction over much of the continent. This is evidence of a crucial role of top predators in maintaining prey biodiversity at large scales in terrestrial ecosystems and suggests that many remaining Australian mammals would benefit from the positive management of dingoes.

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27

Klieve, A. V. "Bacteriophages from the forestomachs of Australian marsupials." Applied and Environmental Microbiology 57, n. 12 (1991): 3660–63. http://dx.doi.org/10.1128/aem.57.12.3660-3663.1991.

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28

Ashwell, K. W. S. "Encephalization of Australian and New Guinean Marsupials". Brain, Behavior and Evolution 71, n. 3 (2008): 181–99. http://dx.doi.org/10.1159/000114406.

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29

Canfield, P. J., e W. J. Hartley. "Tyzzer's disease (Bacillus piliformis) in Australian marsupials". Journal of Comparative Pathology 105, n. 2 (agosto 1991): 167–73. http://dx.doi.org/10.1016/s0021-9975(08)80072-2.

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30

Bennett, MB. "Hopping and bounding locomotion of Australian marsupials". Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 124 (agosto 1999): S9. http://dx.doi.org/10.1016/s1095-6433(99)90034-x.

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31

Ngo, S. N. T., I. Stupans e R. A. McKinnon. "Xenobiotic detoxification in Australian marsupials – An overview". Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 154, n. 1 (settembre 2009): S5. http://dx.doi.org/10.1016/j.cbpa.2009.05.029.

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32

Renfree, Marilyn B. "Diapause, pregnancy, and parturition in Australian marsupials". Journal of Experimental Zoology 266, n. 5 (1 agosto 1993): 450–62. http://dx.doi.org/10.1002/jez.1402660510.

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33

Renfree, M. B., E. S. Robinson, R. V. Short e J. L. Vandeberg. "Mammary glands in male marsupials: I. Primordia in neonatal opossums Didelphis virginiana and Monodelphis domestica". Development 110, n. 2 (1 ottobre 1990): 385–90. http://dx.doi.org/10.1242/dev.110.2.385.

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Abstract (sommario):

Neonates of the American didelphid marsupials Didelphis virginiana and Monodelphis domestica were sexed by karyotype and histologically examined on the day of birth. Mammary anlagen were found in both sexes of both species, but the neonatal males had less than one-third of the full female complement of mammary glands. Male neonates of both species also had paired scrotal bulges anterior to the genital tubercle but these were never present in females, once again raising the question of whether the pouch and scrotum are homologous structures. Mammary anlagen are not found in male neonates of the Australian marsupial species so far studied, which suggests a dichotomy in the control of some aspects of sexual differentiation in the two marsupial lineages.

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34

AUSTEN, JILL M., SIMON A. REID, DERRICK R. ROBINSON, JAMES A. FRIEND, WILLIAM G. F. DITCHAM, PETER J. IRWIN e UNA RYAN. "Investigation of the morphological diversity of the potentially zoonoticTrypanosoma copemaniin quokkas and Gilbert's potoroos". Parasitology 142, n. 11 (10 luglio 2015): 1443–52. http://dx.doi.org/10.1017/s0031182015000785.

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SUMMARYTrypanosomes are blood-borne parasites that can cause severe disease in both humans and animals, yet little is known of the pathogenicity and life-cycles of trypanosomes in native Australian mammals.Trypanosoma copemaniis known to be infective to a variety of Australian marsupials and has recently been shown to be potentially zoonotic as it is resistant to normal human serum. In the present study,in vivoandin vitroexamination of blood and cultures from Australian marsupials was conducted using light microscopy, immunofluorescence, scanning electron microscopy and fluorescencein situhybridization. Promastigote, sphaeromastigote and amastigote life-cycle stages were detectedin vivoandin vitro. Novel trypanosome-like stages were also detected bothin vivoandin vitrorepresenting an oval stage, an extremely thin stage, an adherent stage and a tiny round stage. The tiny round and adherent stages appeared to adhere to erythrocytes causing potential haematological damage with clinical effects similar to haemolytic anaemia. The present study shows for the first time that trypomastigotes are not the only life-cycle stages circulating within the blood stream of trypanosome infected Australian native marsupials and provides insights into possible pathogenic mechanisms of this potentially zoonotic trypanosome species.

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35

Sankovic, Natasha, Wayne Bawden, John Martyn, Jennifer A. M. Graves e Kurt Zuelke. "Construction of a marsupial bacterial artificial chromosome library from the model Australian marsupial, the tammar wallaby (Macropus eugenii)". Australian Journal of Zoology 53, n. 6 (2005): 389. http://dx.doi.org/10.1071/zo05033.

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With the accelerating recognition of the power of comparative genomics, there is now enormous interest in sequencing the genomes of a broad range of species. Marsupials diverged at an important evolutionary time. The model Australian marsupial, the tammar wallaby (Macropus eugenii), has long been a resource for biological and genetic studies of marsupials, and the availability of a bacterial artificial chromosome (BAC) library will be a valuable resource in these studies. A tammar wallaby BAC library was constructed using pRazorBAC vector. It contains 55 296 clones with an average insert size of 108 kb, representing 2.2 times coverage of the wallaby genome (based on an estimated 2.7 × 109 bp haploid genome size). The library was arrayed in 384-well plates, and spotted in duplicate onto nylon membranes. Screening these membranes has yielded clones containing 34 single-copy genes distributed over the genome, while it failed for only one gene. Each probe isolated 1–12 BAC clones and, to date, no chimeric clones have been found. This BAC library will constitute an invaluable resource for creating physical maps, positional cloning of genes and other sequences in the tammar wallaby, as well as comparative mapping studies in mammals.

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36

Breed, W. G. "Sperm-egg interaction in an Australian dasyurid marsupial with special refernce to changes in acrosomal morphology". Zygote 2, n. 3 (agosto 1994): 201–11. http://dx.doi.org/10.1017/s0967199400001994.

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SummaryThe morphology of the acrosome of spermatozoa an Australian daysyurid marsupial during in vivo fertilisation, as seen with the tranamission electron microscope, is described. In some spermatozoa close to the outer zona surface with largely intact acrosomes, eletron-demse struts between the inner and outer acrosomal membranes could be seen; in addition fusion between the outer acrosomal and overlying plasma membranes was sometimes evident. The zona matrix close to the acrosomal region of spermatozoa with heads party embedded within the zona pellucida was less electron-dense and more filamentous than elsewhere; perhaps indicative of local lytic activety. Nevertheless some of these spermatozoa at least had partly intact acrosomes with local regions of electron-dense bridges between the two acrosomal membranes. Spermatozoa with condensed chomatin were also observed within the egg cytoplsam some of which had membranes, vacuoles or close to the dorsal nuclear surface which could, in part, be acrosomal in orgin. These observations lend some support to the recent view, based on findings from an American species, that acrosomal changes of spermatozoa of some marsupials at the of fertillsation may be somewhat similar to those of eutherian mamals in spite of the considerable differences in gamete structure and design. How generally applicable these findings are to all marsupials remains, however, to be determined.

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37

Beyer, Georgia L., e Ross L. Goldingay. "The value of nest boxes in the research and management of Australian hollow-using arboreal marsupials". Wildlife Research 33, n. 3 (2006): 161. http://dx.doi.org/10.1071/wr04109.

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Nest boxes have been recognised as research and management tools for arboreal marsupials in Australia for over 20 years. We review the published literature with the aim of describing the scope of studies conducted in Australia thus far and providing guidance to future research. We recognise three types of application in research: (1) detection of species, (2) study of a species’ ecology, and (3) investigation of box designs preferred by different species. Several species of arboreal marsupial may be detected more readily in nest boxes than by conventional survey techniques, allowing description of key aspects of their ecology; e.g. feathertail glider (Acrobates pygmaeus), eastern pygmy possum (Cercartetus nanus) and brush-tailed phascogale (Phascogale tapoatafa). Identifying the most favoured nest-box design for any species has implications for detection and management uses of nest boxes. More research is needed but preliminary findings suggest that species prefer narrow entrance holes, while height of the nest box above 3 m may be inconsequential. We recognise three types of management application: (1) species introduction, (2) support of populations of endangered species, and (3) strategic placement such as to enhance habitat connectivity. Currently there have been few attempts to use nest boxes to manage arboreal marsupials but further research is needed to realise their potential as a management tool.

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38

Simmonds, Michael J., Oguz K. Baskurt, Herbert J. Meiselman, Michael Pyne, Michael Kakanis, Ekua Brenu, James Keane, Rhys Christy e Sonya M. Marshall-Gradisnik. "Haemorheology of the eastern grey kangaroo and the Tasmanian devil". Australian Journal of Zoology 59, n. 1 (2011): 26. http://dx.doi.org/10.1071/zo10083.

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The blood of two Australian marsupials, the eastern grey kangaroo (Macropus giganteus) and the Tasmanian devil (Sarcophilus harrisii), has been reported to have greater oxygen-carrying capacity (i.e. haemoglobin content) when compared with that of placental mammals. We investigated whether alterations of blood rheological properties are associated with the increased oxygen-carrying capacity of these marsupials. Eastern grey kangaroos (n = 6) and Tasmanian devils (n = 4) were anaesthetised for blood sampling; human blood (n = 6) was also sampled for comparison. Laboratory measurements included blood and plasma viscosity, red blood cell (RBC) deformability, RBC aggregation and the intrinsic tendency of RBC to aggregate, RBC surface charge and haematological parameters. Scanning electron micrographs of RBC from each species provided morphological information. High-shear blood viscosity at native haematocrit was highest for the Tasmanian devil. When haematocrit was adjusted to 0.4 L L–1, lower-shear blood viscosity was highest for the eastern grey kangaroo. RBC deformability was greatly reduced for the Tasmanian devil. Eastern grey kangaroo blood had the highest RBC aggregation, whereas Tasmanian devil RBC did not aggregate. The surface charge of RBC for marsupials was ~15% lower than that of humans. The dependence of oxygen-delivery effectiveness on haemoglobin concentration (i.e. oxygen content) and blood viscosity was quantitated by calculating the haematocrit to blood viscosity ratio and was 15–25% lower for marsupials compared with humans. Our results suggest that environmental pressures since the marsupial–monotreme divergence have influenced the development of vastly different strategies to maintain a match between oxygen demand and delivery.

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39

Antonsson, Annika, e Nigel A. J. McMillan. "Papillomavirus in healthy skin of Australian animals". Journal of General Virology 87, n. 11 (1 novembre 2006): 3195–200. http://dx.doi.org/10.1099/vir.0.82195-0.

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Papillomaviruses are a group of ubiquitous viruses that are often found in normal skin of humans, as well as a range of different vertebrates. In this study, swab samples collected from the healthy skin of 225 Australian animals from 54 species were analysed for the presence of papillomavirus DNA with the general skin papillomavirus primer pair FAP59/FAP64. A total of five putative and potential new animal papillomavirus types were identified from three different animal species. The papillomaviruses were detected in one monotreme and two marsupial species: three from koalas, and one each from an Eastern grey kangaroo and an echidna. The papillomavirus prevalence in the three species was 14 % (10/72) in koalas, 20 % (1/5) in echidnas and 4 % (1/23) in Eastern grey kangaroos. Phylogenetic analysis was performed on the putative koala papillomavirus type that could be cloned and it appears in the phylogenetic tree as a novel putative papillomavirus genus. The data extend the range of species infected by papillomaviruses to the most primitive mammals: the monotremes and the marsupials.

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40

Fulton, Graham R. "Native marsupials as egg predators of artificial ground-nests in Australian woodland". Australian Journal of Zoology 65, n. 3 (2017): 196. http://dx.doi.org/10.1071/zo17038.

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Reviews of nest predation call for the identification of nest predators. The identity of nest predators is perhaps most poorly known for ground-nesting birds. Marsupials are not generally regarded as potential nest-predators of these birds, partly because the biology of rare Australian marsupials is not fully understood due to their rarity. This study identified three marsupials – boodie (Bettongia lesueur), woylie (Bettongia penicillata) and brushtail possum (Trichosurus vulpecula) – taking eggs from artificial nests modelled on that of the threatened painted button-quail (Turnix varius). Approximately one-third of the eggs were taken by the two bettongs and another third by the brushtail possum. I present dietary evidence of bettongs consuming vertebrate items including taking live prey to provide external validation for the notion that they may depredate natural nests. I suggest that more research is required on the impacts of reintroductions to avoid deleterious effects on resident species.

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41

Byers, John A. "The distribution of play behaviour among Australian marsupials". Journal of Zoology 247, n. 3 (marzo 1999): 349–56. http://dx.doi.org/10.1111/j.1469-7998.1999.tb00997.x.

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42

Stefen, Clara. "Tooth enamel structure of some Australian carnivorous marsupials". Alcheringa: An Australasian Journal of Palaeontology 23, n. 2 (gennaio 1999): 111–32. http://dx.doi.org/10.1080/03115519908619325.

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43

Cameron, S. L., P. J. O'Donoghue e R. D. Adlard. "Novel isotrichid ciliates endosymbiotic in Australian macropodid marsupials". Systematic Parasitology 46, n. 1 (maggio 2000): 45–57. http://dx.doi.org/10.1023/a:1006208802110.

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44

Fan, Z. W., J. Eng, G. Shaw e R. S. Yalow. "Cholecystokinin octapeptide purified from brains of Australian marsupials". Peptides 9, n. 2 (marzo 1988): 429–31. http://dx.doi.org/10.1016/0196-9781(88)90280-x.

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45

Ngo, S. N. T., I. Stupans e R. A. McKinnon. "Xenobiotic metabolism in Australian marsupials: A molecular perspective". Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology 154, n. 1 (settembre 2009): S2. http://dx.doi.org/10.1016/j.cbpa.2009.05.018.

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46

Fidler, Andrew E., Andrea H. Western, Nicole Griffith, Lynne Selwood, Vicki Stent e Kenneth P. McNatty. "Production of a biologically active recombinant marsupial growth factor using the methylotrophic yeast Pichia pastoris". Reproduction, Fertility and Development 14, n. 6 (2002): 327. http://dx.doi.org/10.1071/rd02040.

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The cytokine stem cell factor (SCF) and its interaction with its receptor c-kit plays an important role in the development of germ cells in eutherians. To investigate the putative roles of the SCF/c-kit system in marsupials, recombinant Australian brushtail possum (Trichosurus vulpecula) SCF was purified after secretion by the methylotrophic yeast Pichia pastoris. The purification procedure utilized Ni2+ affinity chromatography with a poly-histidine tag engineered onto the C-terminus of the recombinant SCF. The recombinant possum SCF had a molecular weight of 48 kDa, as determined by sodium dodecyl sulphate–polyacrylamide gel electrophoresis, and was biologically active with respect to its ability to maintain and induce proliferation of marsupial primordial germ cells in vitro. Furthermore, the recombinant possum SCF stimulated proliferation of the cell line TF1 and this bioactivity could be inhibited using an antibody directed against recombinant mouse SCF. This source of biologically active marsupial SCF may prove useful in future studies of marsupial development.

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47

Isaac, JL. "Possums: The Brushtails, Ringtails and Greater Glider. Anne Kerle. A Review by Joanne L Isaac." Australian Mammalogy 24, n. 2 (2002): 249. http://dx.doi.org/10.1071/am02249.

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DESPITE their almost ubiquitous presence across Australia, contemporary research on the biology, ecology and conservation status of the so-called 'common' possums is scant and inadequate. The majority of possum studies have been a result of the huge research effort in New Zealand to control and eradicate the common brushtail possum, a notorious introduced pest, and have concentrated primarily upon reproductive physiology. The conspicuous lack of ecological data on the larger possums across their native Australian range is particularly disturbing since evidence suggests that a number of these species are disappearing from large tracts of Australia. However, Possums: the brushtails, ringtails and greater glider, part of the Australian Natural History Series, provides a long overdue summary of up-to-date research on these familiar and intriguing marsupials.

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48

Jones, Menna, e Chris Dickman. "Introduction: Carnivorous marsupials". Wildlife Research 28, n. 5 (2001): I. http://dx.doi.org/10.1071/wrv28n5_in.

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Population dynamics and movements were investigated in a population of Pseudantechinus macdonnellensis, a dasyurid marsupial occupying rocky habitats in the Australian arid zone. Intra-annual cycling in abundance, activity and numbers of resident and transient individuals was not regular from year to year, although the number of residents was high compared with the number of transients. Juvenile recruitment varied between years and was as low as 18%. Densities were low (0.05–0.2 ha–1 for females and 0.05–0.3 ha–1 for males), and individuals exhibited large stable long-term ranges – mean Minimum Convex Polygon (MCP) area for males was 427 m2 and for females 171 m2. The constraints of the monoestrous, synchronised reproductive strategy of P. macdonnellensis, together with the ameliorating effect of its rocky habitat, which may decrease food limitation and increase survival, seem to have produced a different pattern of population dynamics to that seen in arid-zone dasyurids that are polyoestrous plains-dwellers. The patterns of movement in P. macdonnellensis also differ from plains-dwelling species, in which individuals display high life-time mobility. The existence of large but non-drifting ranges in P. macdonnellensis may be seen as a consequence of a low but relatively predictable food supply, which precludes the necessity for individuals to shift their activity to temporary patches of high food supply, but requires them to occupy a large range to obtain enough food to meet energy requirements.

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Valentine, Leonie E., Hannah Anderson, Giles E. StJ Hardy e Patricia A. Fleming. "Foraging activity by the southern brown bandicoot (Isoodon obesulus) as a mechanism for soil turnover". Australian Journal of Zoology 60, n. 6 (2012): 419. http://dx.doi.org/10.1071/zo13030.

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Mammals that forage for food by biopedturbation can alter the biotic and abiotic characteristics of their habitat, influencing ecosystem structure and function. Bandicoots, bilbies, bettongs and potoroos are the primary digging marsupials in Australia, although most of these species have declined throughout their range. This study used a snapshot approach to estimate the soil turnover capacity of the southern brown bandicoot (Isoodon obesulus, Shaw 1797), a persisting digging Australian marsupial, at Yalgorup National Park, Western Australia. The number of southern brown bandicoots was estimated using mark–recapture techniques. To provide an index of digging activity per animal, we quantified the number of new foraging pits and bandicoot nose pokes across 18 plots within the same area. The amount of soil displaced and physical structure of foraging pits were examined from moulds of 47 fresh foraging pits. We estimated that an individual southern brown bandicoot could create ~45 foraging pits per day, displacing ~10.74 kg of soil, which extrapolates to ~3.9 tonnes of soil each year. The digging activities of the southern brown bandicoots are likely to be a critical component of soil ecosystem processes.

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Cruz, Y. P., H. Morton, A. C. Cavanagh, L. Selwood, S. D. Wilson e M. Sasaki. "Early pregnancy factor in marsupials". Australian Journal of Zoology 54, n. 3 (2006): 211. http://dx.doi.org/10.1071/zo05050.

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Maternal recognition of pregnancy in marsupials occurs in more subtle ways than it does in eutherians. For instance, unlike in eutherians, the plasma progesterone profiles of pregnant and non-pregnant animals are similar during the luteal phase. It is typically during the brief luteal phase that both gestation and parturition occur in marsupials. Yet histological and physiological changes have been documented between gravid and non-gravid uteri in certain monovular marsupials and between pregnant and non-pregnant animals in polyovular marsupials. Early pregnancy factor (EPF), a 10.8-kDa serum protein known to be homologous to chaperonin 10, is associated with maternal immunosuppression, embryonic development and pregnancy in eutherian mammals. It has been reported in two Australian marsupials: the dasyurid Sminthopsis macroura and the phalangerid Trichosurus vulpecula. This paper documents its occurrence in the New World didelphid Monodelphis domestica. EPF is detectable by rosette inhibition assay in the peripheral circulation of pregnant but not of non-pregnant or pseudopregnant animals. Our work focuses on the embryo–maternal signalling role of EPF during pregnancy. Because progesterone-driven changes are similar in pregnant and non-pregnant marsupials, these animals are an excellent laboratory model in which to investigate the role of EPF in orchestrating the physiological changes necessary to sustain pregnancy.

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