mixed function oxidase activity in a marsupial. the quokka (seton;x brachyurus).components of the cytochrome p-450 pathway and rates of oxidative hepatic metabolism of the substrates, ethylmorphine, 3,4-benzpyrene, and aniline, have been investigated in a marsupial (the quokka, setonix brachyurus) and compared with those of the rat. in general the quokka had lower rates of drug metabolism and higher km values than those found in the rat. sex differences in vmax and km were also found for the quokka. these species and sex differences in oxidative drug metabolism did not corr ...19766222
marsupial immunoglobulins: the distribution and evolution of macropod igg2, igg1, igm and light chain antigenic markers within the sub-class metatheria.the distribution within australian and american marsupials of the heavy and light chain antigenic markers identified by antisera to purified quokka (setonix brachyurus) immunoglobulins is described. markers for igm and igg2 constant region determinants as well as for light chains were widely distributed in australian species and were also detected in didelphis, the american opossum, thus indicating a long-term structural conservatism of some immunoglobulins within the marsupials. more detailed a ...197773503
histamine in the tissues of the marsupial setonix brachyurus (the quokka).passive cutaneous anaphylactic (pca) reactions in the marsupial setonix brachyurus (the quokka) were completely inhibited by the histamine antagonist mepyramine maleate, but were unaffected by disodium cromoglycate or the serotonin antagonist, methysergide. histological examination of quokka skin indicated that mast cell degranulation occurred during the pca reaction in this marsupial and animals whose skin was relatively deficient in mast cells were poor pca recipients. in contrast to many euth ...1975234921
induction of long-term tolerance in the quokka (setonix brachyurus) by thymus and skin allografts into early pouch young.intact quokkas (setonix brachyurus) were grafted with thymus and skin as neonates. fifty seven percent of primary thymus grafts persisted when donors were less than 32 days of age, compared with only 20% when the dornors were juveniles. this suggested that neonatal tissue was more readily accepted than tissue from adult animals. when the recipients had left the pouch, induced tolerance was tested by grafting thymus and skin from the original donors. second thymus grafts were generally unsuccessf ...1978375905
the in vitro response to phytomitogens of marsupial leukocytes.leukocytes from two macropod marsupials, the quokka (setonix brachyuras) and the tammar (macropus eugenii) were separated from whole blood by dextran sedimentation and established in culture with either phytohemagglutinin-p, concanavalin a, or pokeweed mitogen. the leukocyte response to each mitogen, as measured by the incorporation of tritiated thymidine into dna, was similar to that described in other experimental systems. these results suggest that the functional elements of the cellular immu ...1976979144
nipple reattachment by disloged pouch young of the quokka, setonix brachyurus. 19751110470
the effect of thymectomy on the lymphoid tissues of the quokka (setonix brachyurus). 19751164260
gravity as the sole navigational aid to the newborn quokka. 19761250337
quokka bites. the first report of bites from an australian describe the incidence and natural history of bites from the quokka, a small wallaby.19921453997
early development of retinal ganglion cell dendrites in the marsupial setonix brachyurus, quokka.the dendritic morphology of retinal ganglion cells was studied in flat-mounted retinae of the marsupial setonix brachyurus, quokka. in the adults, horseradish peroxidase (hrp) was applied to the vitread surface of flattened retinae. wide-, large-, medium-, and small-field classes appeared to correspond to gamma, alpha, delta, and beta cells, respectively, in the cat (boycott and wässle, j. physiol. 249:397-419, 1974). to reveal the early stages of dendritic development, hrp was placed on the opt ...19902324323
expanded retinofugal projections to the dorsal lateral geniculate nucleus and superior colliculus after unilateral enucleation in the wallaby setonix brachyurus, quokka.we removed one eye of quokkas either neonatally, before retinal innervation of visual centres, or at 35-40 days postnatal, when projections overlap bilaterally and are more widespread than in the adult. retinal projections to the dorsal lateral geniculate nucleus and superior colliculus at postnatal day 100 were demonstrated following anterograde transport of horseradish peroxidase. there were significant reductions in the size of the dorsal lateral geniculate nucleus and superior colliculus ips ...19892776298
retinal ganglion cell number is unchanged in the remaining eye following early unilateral eye removal in the wallaby setonix brachyurus, quokka.the expanded visual projections which develop after unilateral eye removal have been associated in some studies, but not in others, with the survival of more ganglion cells than normal in the remaining eye. we have addressed this issue using the small wallaby setonix brachyurus, quokka. moreover to determine whether more ganglion cells survive when the eye is removed at a very early stage, we have compared the effect of enucleations at two ages. these were within 3 days of birth, before optic fi ...19892776299
cell death in the inner and outer nuclear layers of the developing retina in the wallaby setonix brachyurus (quokka).we have examined the number and distribution of dying cells in the developing inner (inl) and outer (onl) nuclear layers of sectioned quokka retinae (n = 31) from embryonic day (e)24 to postnatal day (p)192. before birth, dying cells were seen in the optic fissure. thereafter two major phases of cell death took place in the inl. the first phase was more pronounced within the vitread part with peak numbers of dying cells at p50. by contrast, during the second phase, cell death was more extensive ...19892808756
displaced retinal ganglion cells in the wallaby setonix brachyurus.displaced ganglion cells have been examined in wholemounted and sectioned retinae following bilateral injection of horseradish peroxidase into optic tracts of the wallaby, setonix brachyurus, "quokka". such cells, which lie in the vitread part of the inner nuclear layer, are located mainly in superior retina as a streak-like band dorsal to the area centralis and visual streak of orthotopic ganglion cells. only between 1 and 2% of the total ganglion cell population were displaced, but an analysis ...19873424674
patterns of cytogenesis in the developing retina of the wallaby setonix brachyurus.patterns of mitosis were examined during development from embryonic day (e) 19, 9 days before birth, for retinae of the wallaby setonix brachyurus, using cresyl violet stained material. for neural retina, mitosis took place at the ventricular surface from the earliest stage of eye formation until postnatal day (p) 100. numbers of mitotic figures reached a peak of approximately 12,000 by p43. average densities ranged between 300/mm2 and 600/mm2 up to p12 and then fell to below 50/mm2 by p25 befor ...19873434843
in vitro antibody-mediated macrophage activity on breinlia macropi microfilariae. i. adherence and cytotoxicity.intense adherence accompanied by cytotoxicity, which initially occurred at 4 h of interaction was observed when the microfilariae of breinlia macropi were introduced to cultures of quokka peritoneal macrophages previously sensitized in 20% immune serum. no significant difference in the adherence or cytotoxic effects was observed among macrophages from normal, microfilaraemic and amicrofilaraemic quokkas. however, the serum component mediating these effects was found only in microfilaraemic and s ...19863703569
estradiol-17 beta secretion by the newly formed corpus luteum of a macropodid marsupial, the quokka (setonix brachyurus).the production of significant amounts of estradiol-17 beta from the 2-day-old corpus luteum of the macropodid marsupial, setonix brachyurus (quokka), was shown using an in vitro perifusion system. sliced corpora lutea and finely chopped extra-luteal ovarian tissue (cortex plus interstitial tissue) were perifused separately for 2 hr, in tandem for the next hour (with the perifusate from the ovarian tissue directed into the chamber containing the corpora lutea), and separately again for a further ...19921426945
temperature regulation and oxygen consumption in the developing macropod marsupial setonix brachyurus.1. when kept at ambient temperatures of 17-5 and 24 degrees c the colonic temperatures of joeys younger than 166 days declined to near ambient temperature. pouch joeys of 166 days and older were however able to maintain their colonic temperatures at about 35 degrees c. 2. joeys first developed the ability to sustain high o2 consumption rates in response to cooling, when aged between 144 and 169 days. only when this latter facility was fully developed in ontogeny could body temperature be maintai ...1977894610
blood corticosteroids in australian marsupial and placental mammals and one monotreme.peripheral blood corticosteroid levels were determined in nine species of australian marsupial (eastern grey kangaroo, black-tailed, bennett's and pademelon wallabies, quokka, wombat, koala and western native and tiger cats), one species of monotreme (echidna) and one placental australian mammal (dingo). animals were obtained or bled with minimal disturbance and came from areas considered to have adequate sodium content of the vegetation. aldosterone, corticosterone, cortisol, 11-deoxycorticoste ...1976181514
metabolic effects of cortisol, acth, adrenalin and insulin in the marsupial sugar glider, petaurus breviceps.the effects of cortisol, acth, adrenalin and insulin on indices of carbohydrate, fat and protein metabolism were investigated in the conscious marsupial sugar glider petaurus breviceps. short-term i.v. infusion of cortisol at dose rates of 0.02, 0.2 and 1.0 mg/kg per h caused the plasma glucose concentration to rise sharply from the normal range of 3.3-4.4 to 8.1-8.7 mmol/l at the end of the infusion period without significant alteration in plasma free fatty acid (ffa), amino acid or urea concen ...19902174452
immunoglobulin classes carrying homocytotropic and passive hemagglutinating antibody activities in the marsupial setonix brachyurus (the quokka).on the basis of their physicochemical and antigenic properties, and by analogy with guinea pig immunoglobulins, two antibody classes in the serum of the marsupial setonix brachyurus have been classified as igg1 and igg2 isotypes. the analogy between these marsupial immunoglobulins and those of eutherian (placental) species was extended by an investigation of their biological activities. the electrophoretically slow antibody (igg2) fixed hemolytic complement, precipitated soluble antigen and pred ...1975803934
the immune response of the quokka (setonix brachyurus). the production of a low molecular weight antibody. 19724112736
biphasic retinal neurogenesis in the brush-tailed possum, trichosurus vulpecula: further evidence for the mechanisms involved in formation of ganglion cell density gradients.we investigated cell generation in the retina of the brush-tailed possum (trichosurus vulpecula) by using tritiated (3h)-thymidine labelling of newly generated cells. animals aged between postnatal day (p) 5 and 85 each received a single injection of 3h-thymidine. following autoradiographic processing, maps of labelled cells were constructed from retinal sections. retinal cell generation takes place in two phases, the first is concluding in the retinal periphery at p53 as the second is seen to c ...19921469115
immediate hypersensitivity responses in the marsupial setonix brachyurus (the quokka). characterization of the homocytotropic antibody. 19744141246
immunoglobulins of the marsupial setonix brachyurus (quokka). characterization of three major serum classes, igg2, igg1 and igm. 19744141695
iron-binding properties and amino acid composition of marsupial transferrins: comparison with eutherian mammals and other vertebrates.1. some physicochemical properties of transferrin from three marsupials, viz a possum (trachosurus vulpecula), a kangaroo (macropus fuliginosus) and the quokka (setonix brachyurus) were studied and compared with those of transferrins from mammalian and non-mammalian vertebrate species. 2. the molecular weight of the marsupial transferrins fell within the range of 76,000-79,000 daltons. 3. the marsupial transferrins were similar to the transferrins of eutherian mammals with respect to optical spe ...19882899476
the changes in the serum and milk whey proteins during lactation and suckling in the quokka (setonix brachyurus). 19684173032
time course of homocytotropic and passive haemagglutinating antibody synthesis in the marsupial setonix brachyurus (the quokka). 19744372186
proceedings: development of the innervation in the heart of the quokka joey setonix brachyurus. 19744448782
immediate hypersensitivity responses in the marsupial setonix brachyurus (the quokka). biological properties of the homocytotropic antibody. 19744472609
salmonella javiana infection in an infant associated with a marsupial, the quokka, setonix brachyurus, in western australia.salmonella javiana, a serotype rarely isolated in australia, has been recovered from the faeces of a 14-month-old infant with symptoms of enteritis.the child had been closely associated with a marsupial species, the quokka, during a vacation on rottnest island in western australia, and s. javiana was isolated from faecal pellets from adult quokkas, and also from a snake collected on the island.sampling revealed a high incidence of salmonella infection in the quokkas. in all, 62 out of 87 animals ...19734518341
effect of thymectomy on skin allograft survival in a macropod marsupial, setonix brachyurus. 19744588155
the microbial flora of the gut of the pouch-young and the pouch of a marsupial, setonix brachyurus. 19724624672
the effect of neurohypophysial hormones on the uterus of a marsupial species, the quokka (setonix brachyurus). 19724636381
role of transferrin in iron uptake by the brain: a comparative study.the role of specific transferrin (tf) and tf receptor interaction on brain capillary endothelial cells in iron transport from the plasma to the brain was investigated by using tf from several species of animals labeled with 59fe and 125i, and 15-day and adult rats. the rate of iron transfer was much greater in the 15-day rats. it was greatest with tf from the mammals, rat, rabbit and human, but much lower with chicken ovotransferrin and quokka (a marsupial), toad, lizard, crocodile, and fish tf. ...19911744249
distinctive pattern of organisation in the retinofugal pathway of a marsupial: ii. optic the mammalian optic chiasm retinal axons from each eye divide into two populations, those that decussate and those that remain uncrossed. in eutherian (placental) mammals, the separation of these pathways is not reflected in the structure of the chiasm. the two populations from each eye are mixed through each hemichiasm, segregating only at the midline, where the uncrossed projection turns back. in this study the optic chiasm of a marsupial, the wallaby, setonix brachyurus (quokka) has been i ...19921484119
the effect of thymectomy on response to various antigens of a marsupial setonix brachyurus (quokka). 19724656785
distinctive pattern of organisation in the retinofugal pathway of a marsupial: i. retina and optic nerve.the nasotemporal division in the retina and the pattern of crossed and uncrossed axons in the optic nerve were determined in an australian marsupial, a wallaby, setonix brachyurus (the quokka), following unilateral horseradish peroxidase injections into primary visual centres. the gross morphology of the nerve was also examined. ipsilaterally projecting ganglion cells were restricted to the temporal retina, whereas those that project contralaterally were located in all retinal regions. the morph ...19921484118
generation of retinal cells in the wallaby, setonix brachyurus (quokka).we have examined the generation of retinal cells in the wallaby, setonix brachyurus (quokka). animals received a single injection of tritiated thymidine between postnatal days 1-85 and retinae were examined at postnatal day 100. retinae were sectioned, processed for autoradiography and stained with cresyl violet. ganglion cells were labelled by injection of horseradish peroxidase into the optic tracts and primary visual centres. other cells were classified according to their morphology and locat ...19892761691
the accessory optic system of the wallaby, setonix brachyurus: anatomy in normal animals and after early unilateral eye removal.we have traced primary visual projections to nuclei of the accessory optic system in the mature wallaby, setonix brachyurus, the "quokka," following unilateral intraocular injections of horseradish peroxidase. the organization of pathways and nuclei is similar to that of other marsupials and to that of eutherian mammals. the dorsal, lateral and medial terminal nuclei receive bilateral input, though nuclei ipsilateral to the injected eye are weakly labelled in comparison with their contralateral ...19882463278
effect of available surface water on levels of antidiuretic hormone (lysine vasopressin) and water and electrolyte metabolism of the rottnest island quokka (setonix brachyurus).a sensitive radioimmunoassay was developed to measure circulating levels of the neurohypophysial peptide lysine vasopressin (lvp) in the marsupial quokka (setonix brachyurus), which is abundant on rottnest island off the coast of western australia. animals from locations on the island where free water is completely absent were compared in midsummer with animals from sites where brackish water is available and utilized by the quokkas. in the animals from west end, where free water is absent, circ ...19902295426
generation and death of cells in the dorsal lateral geniculate nucleus and superior colliculus of the wallaby, setonix brachyurus (quokka).to study postnatal cell generation in primary visual centres of the quokka, tritiated thymidine was injected into pouch-young aged postnatal day (p)1-p85. brains were examined at p100, just before eye-opening, when primary visual projections are essentially mature. neurons in the dorsal lateral geniculate nucleus (dlgn) and superior colliculus (sc) were generated at p1-p10 and p1-p18 respectively. peak numbers of labelled cells were seen at p3 and p5 in the dlgn and sc. cell death was assessed i ...19911770170
delayed hypersensitivity in the marsupial setonix brachyurus (quokka). 19725031325
the organization of dense projections in synapses of the brain of a marsupial, setonix brachyurus. 19725073213
the homology of the premolar teeth in setonix brachyurus (macropodidae: marsupialia). 19665226519
an account of the enamel cord in setonix brachyurus (marsupialia) and on the presence of an enamel knot in trichosurus vulpecula. 19675227473
principles of myopathology as illustrated in the nutritional myopathy of the rottnest quokka (setonix brachyurus). 19665230219
the vascularity of the enamel organ in the developing teeth of setonix brachyurus and trichosurus vulpecula (marsupialia). 19675237930
development of lymphoid tissue in a marsupial, setonix brachyurus (quokka).the development of the lymphoid tissues in a macropod marsupial is described. the liver is the only functional haemopoietic tissue at birth. large lymphocytes first appear in the cervical thymus at 2 days, and in the thoracic thymus at 4 days after birth. small lymphocytes appear 1-2 days later. the histological development of the two glands is similar, but the thoracic thymus develops much more slowly than the cervical. the appearance of hassall's corpuscles in both thymus glands correlates wit ...19751154997
electrophysiological studies in the rottnest quokka with nutritional myopathy. 19695373689
the ultrastructure of the neonatal thymus of a marsupial, setonix brachyurus. 19695377806
numbers of axons in the optic nerve and of retinal ganglion cells during development in the marsupial setonix brachyurus.numbers of axons during postnatal development in the optic nerve of the marsupial setonix brachyurus were estimated from electron micrographs. between 14 and 45 days axon totals rose 10-fold from 95,000 to 961,000. thereafter, counts decreased gradually by almost 5-fold stabilising at the adult level of 180,000-224,000 between 130-150 days. myelinated axons were first seen at 85 days and constituted 76% of all axons by 150 days, compared to almost 100% in the adult. at comparable stages of devel ...19863948024
the corticospinal tract of the wallaby (setonix brachyurus). 19705413634
growth of striated muscle in an australian marsupial (setonix brachyurus). 19705442226
the corticospinal tract of the quokka wallaby (setonix brachyurus). 19715556667
estimation of michaelis--menten constants in microsomal enzyme systems by the direct linear plot and least squares regression.1. data from in vitro liver microsomal metabolism of ethylmorphine aniline and benzpyrene in male rats and male and female quokkas (setonix brachyurus) were fitted to the michaelis--menten equation by wilkinson's non-linear regression procedure and eisenthal and cornish-bowden's direct linear plot. 2. ethylmorphine and aniline metabolism in the male quokka were non-ideal, but in all other instances there were no differences in the performance of the two methods.1978685293
observations on the behavior of the marsupial setonix brachyurus (quoy and gaimard) in an enclosure. 19695813259
environmental influences on daily and seasonal activity in setonix brachyurus (quoy and gaimard) (marsupialia). 19655835844
oxygen consumption during pouch development of the macropod marsupial setonix brachyurus.1. measurements of o(2) consumption at 9 or 10 temperatures in the 20-40 degrees c ambient temperature range were made on joeys with ages selected to cover the 180-day period of pouch occupancy.2. the rate of o(2) consumption of joeys younger than 100 days increased directly with ambient temperature.3. after 100 days of age the o(2) consumption rate at low temperatures rose and at about 140 days of age a constant rate was maintained over the full ambient temperature range.4. heat transfer from j ...19665972171
regeneration of skeletal muscle in the rottnest quokka. 19665973145
toxoplasmosis in the rottnest quokka (setonix brachyurus). 19666008521
mortalities associated with herpesvirus infection in captive macropods.fatal cases of herpesvirus infection in a quokka (setonix brachyurus), eight grey dorcopsis wallabies (dorcopsis muelleri luctuosa) in two separate outbreaks, as well as presumptive fatal herpesvirus infection in a western grey kangaroo (macropus fuliginosus) are described. all were captive animals and deaths were preceded by a period of stress. lesions occurred most often in alimentary tract epithelium, respiratory tract, skin, genital epithelium, conjunctivae, liver and adrenal cortex. herpesv ...19816264169
marsupial neurohypophysial hormones: identification of mesotocin, lysine vasopressin, and phenypressin in the quokka wallaby (setonix brachyurus).the neurohypophysial hormones of the quokka wallaby (setonix brachyurus) have been isolated through preparative high pressure liquid chromatography (hplc). one oxytocin-like and two vasopressin-like peptides have been found. these peptides have been characterized by their amino acid composition and by their retention time in hplc. mesotocin ([i1e8]-oxytocin) has been identified by amino acid composition, polar partition chromatography, high pressure liquid chromatography with a reversed phase co ...19836618161
a study of isolation procedures for multiple infections of salmonella and arizona in a wild marsupial, the quokka (setonix brachyurus). 19826763026
comparison of rate of hepatic metabolism in vitro and half-life for antipyrine in vivo in three species.1. a radiometric assay for the total metabolism of antipyrine in vitro by hepatic microsomal preparations has been developed. 2. apparent km and v values for the process were determined in rats, rabbits and in a marsupial (the quokka; setomix brachyurus). km values were similar in rats and rabbits (3.5 and 5 mm respectively) but were somewhat lower in quokkas (1.4--1.5 mm). estimates of v ranged from 49--64 nmol/mg microsomal protein/10 min and were similar in all three species. pretreatment of ...1979433309
resistance to the nitrogen-mobilizing, diabetogenic action of cortisol in a small wallaby (setonix brachyurus). 19817011896
uterine factors and delayed implantation in macropodid marsupials.local factors controlling uterine functions in macropodids are reviewed and the components of uterine fluids are examined. activation of the diapausing blastocyst and subsequent development of the expanding vesicle are associated with a changing uterine environment. concentrations of proteins, calcium and zinc in uterine exudates alter during gestation; the changes appear to be related both to the stage of development of the conceptus and to the hormonal milieu. in addition the endometrium itsel ...19817014865
quantitative alterations of the aerobic bacterial flora of the pouch of setonix brachyurus (quokka) during oestrus, anoestrus, pregnancy and lactating anoestrus (pouch young). 19817041871
adrenocortical function and a field population of a macropodid marsupial (setonix brachyurus, quoy and gaimard).concentrations of corticosteroids and aldosterone have been measured in the plasma and related to the maximum cortisol binding capacity, to the concentration of sodium and potassium of the plasma and to the condition of the animals, in a natural population of the quokka (setonix brachyurus, quoy & gaimard) on rottnest island, western australia. a marked population in one area has been repetitively sampled at approximately 6 week intervals over a period of 2 years. animals were found to be in sig ...1979225402
characterization and properties of a progesterone receptor in the uterus of the quokka (setonix brachyurus).a progesterone receptor system, with a high specificity for progestins, was detected in the uterine tissue of the marsupial, setonix brachyurus (quokka), using the synthetic progestin 17 alpha, 21-dimethyl-19-nor-4,9-pregnadiene-3,20-dione (r5020). the apparent equilibrium dissociation constant of the ligand binding to the cytosolic component was 2.2 nmol/l, and to the nuclear component 4.8 nmol/l. significant loss of binding ability of the receptor occurred when cytosol was pretreated with dext ...19827200116
development of the hepatic mixed function oxidase system in a marsupial, the quokka (setonix brachyurus). 1978103246
cell death in the developing retinal ganglion cell layer of the wallaby setonix brachyurus.the distribution and number of dying cells in the developing retinal ganglion cell layer of the wallaby setonix brachyurus were assessed by using cresyl violet stained tissue. the density of dying cells has been expressed per 100 live cells for the entire retinal surface, data being presented as a grid of 500 micron squares. for statistical analysis, retinae were divided into 8 regions; dorsal, ventral, nasal, and temporal quadrants, each further divided into center and periphery. this method al ...19873680622
the thymus glands of a marsupial, setonix brachyurus (quokka), and their role in immune responses. structure and growth of the thymus glands. 19724654391
iron metabolism during lactation and suckling in a marsupial, the quokka (setonix brachyurus).the iron status and transfer of iron through the milk during lactation were determined in a marsupial, the quokka, setonix brachyurus. lactating animals were not anaemic and had similar liver and spleen non-haem iron values to non-lactating female adult animals but about 40% less non-haem iron than male adults. the milk iron concentration was very high during the period of lactation when the young is confined to the pouch, averaging about 20 micrograms/ml (eight times the plasma iron concentrati ...19862875836
the complete primary structure of late lactation protein from quokka (setonix brachyurus).the complete primary structure of the late lactation protein from the milk of quokka (setonix brachyurus) is presented. the amino acid sequence was established by n-terminal sequence analysis of high-performance liquid chromatography purified intact protein and peptides isolated from chemical and enzymatic digests of the protein. the protein contains 158 residues including four cysteines. the sequence comparison with the tamar wallaby (macropus eugenii) late lactation protein shows only five dif ...19947832979
horizontal cells in the retina of the brush-tailed possum.most species of eutherian (placental) mammals examined have two types of horizontal cell, one is axonless and the other has a short axon. we have recently shown that a marsupial, the quokka wallaby, also has two types of horizontal cell and that the axonless cell in this species has unusual stubby processes that pass through the inner nuclear layer to reach the inner plexiform layer. in order to discover whether these descending processes are a feature of marsupials in general, i examined the mo ...19948013586
changing distribution of retinal ganglion cells during area centralis and visual streak formation in the marsupial setonix brachyurus.injections of the axonal marker horseradish peroxidase (hrp) were made into optic tracts and/or visual centres of setonix brachyurus, a small wallaby (quokka) during development and in adults. distributions of hrp-labelled and unlabelled cells in the retinal ganglion cell layer were estimated from sections or wholemounts counterstained with cresyl violet. between 20 and 40 days postnatal we did not observe an area centralis or visual streak in either the labelled or unlabelled cell populations. ...19854075108
the thymus glands of a marsupial, setonix brachyurus (quokka), and their role in immune responses. effect of thymectomy on somatic growth and blood leucocytes. 19724654392
development of visual projections in the marsupial, setonix brachyurus.retinal projections to the primary visual centres were studied following injection of tritiated proline into one eye in the marsupial, setonix brachyurus between 10 and 100 days postnatal and in adults. initially, projections from the two eyes overlapped extensively, particularly between 20 and 50 days. there was a gradual refinement thereafter, including a segregation of inputs from the two eyes within both the lateral geniculate nucleus (lgn) and superior colliculus (sc) by 70 days. such refin ...19863826648
marsupial immunoglobulins: an immunoglobulin molecule resembling eutherian iga in serum and secretions of setonix brachyurus (quokka). 19744134066
the effect of neonatal thymectomy on the ontogeny of mitogen responses in the quokka (setonix brachyurus). 1977611019
plasma corticosteroids and the effect of adrenocorticotrophin in a macropodid marsupial (setonix brachyurus, quoy & gaimard). 1977201720
a histochemical study of denervated marsupial hemidiaphragm.the marsupial (quokka) hemidiaphragm showed postdenervation hypertrophy and subsequent atrophy. the type ii muscle fibres hypertrophied up to 20 days postoperation and then regressed. however, the type i fibres hypertrophied throughout the experimental period (100 days) studied. unlike denervated eutherian hemidiaphragm, fibre-splitting was absent in the denervated marsupial muscle. an enhancement of the atpase reaction in the denervated type i fibres may be due to dedifferentiation. presumably ...1979156124
in vitro antibody-mediated macrophage activity on breinlia macropi microfilariae. ii. ultrastructural and video recording investigations of adherence and recordings and ultrastructural studies have revealed an intricate sequence of antibody-mediated cytotoxic activity by quokka peritoneal macrophages on breinlia macropi microfilariae. the microfilaricidal activity was effected by at least two types of macrophages measuring 17 micrometers and 8 micrometers in diameter respectively. the relatively large macrophages were responsible for trapping, encircling and eventually degrading the highly motile microfilariae in a sequence of events in whi ...19863725416
fine structure of the retinal pigment epithelium and photoreceptor cells of an australian marsupial setonix brachyurus. 19734791801
transient axonal side branches in the developing mammalian optic nerve.optic axons were labelled with horseradish peroxidase to establish the presence of side branches and examine their distribution and morphology in the developing optic nerve of the quokka wallaby, setonix brachyurus, the cat and rat at stages when axon numbers are at their peak. in each species, three quarters of the axons were essentially straight and lacked side branches. the remaining axons took significantly longer paths and bore side branches, mostly at points where axons undulated or change ...19989394042
the early development of the incisor teeth of setonix brachyurus (macropodidae: marsupialia) with special reference to the prelacteal teeth. 19685238886
iron in milk and milk fractions of lactating rats, rabbits and quokkas. 19734736231
dopaminergic amacrine cells in the retina of the possum, trichosurus vulpecula.the common brush-tailed possum trichosurus vulpecula is a small diprotodont marsupial common to both urban and natural environments. this is the first analysis of the neurotransmitter content of its retinal cells and, as the possum is a nocturnal forager, it was appropriate to begin with the dopaminergic amacrine cells that form an essential link in the modulation of the rod pathways subserving nocturnal vision. these results were compared with those from another diprotodont, the marsupial walla ...19989682872
effects of cabergoline on reproduction in three families of australian marsupials.the effects of the prolactin inhibiting drug, cabergoline, on pregnant and lactating marsupials were investigated in four species from three diverse families: the tammar wallaby, macropus eugenii, the quokka, setonix brachyurus, the brushtail possum, trichosurus vulpecula, and the fat-tailed dunnart, sminthopsis crassicaudata. in tammar wallabies, 20 micrograms cabergoline kg-1 injected intramuscularly 1 day before expected birth did not alter the timing of parturition but neonates died within a ...19989713388
the effect of oestrus and the presence of pouch young on aerobic bacteria isolated from the pouch of the tammar wallaby, macropus eugenii.qualitative changes in the culturable, aerobic bacterial flora isolated from the tammar pouch have been documented over the period leading up to oestrus, at the time of anticipated birth and in absence and presence of pouch young of varying ages. in a group of 12 animals studied thirty species of aerobic bacteria were isolated. twenty five species were found in pouches with no pouch young, 9 in pouches with young less than 3 weeks of age and 9 in pouches containing older animals. gram positive o ...19989775355
corticosteroids in the adrenal venous and heart blood of the quokka, setonix brachyurus (marsupialia: macropodidae). 19695403616
the evolution of an area centralis and visual streak in the marsupial setonix brachyurus.the distribution, morphology, size, and number of cells in the retinal ganglion layer of the marsupial setonix brachyurus, "quokka," was studied from 25 days postnatal to adulthood using nissl-stained wholemounts. the total cell population was evenly distributed up to 50 days, but by 75 days highest densities were generally observed in a broad band extending across the nasotemporal axis. at 87 days, a temporally situated area centralis was seen for the first time. this was embedded in a horizont ...19836863603
salmonella infections in a marsupial, the quokka (setonix brachyurus), in relation to seasonal changes in condition and environmental unusual abundance of salmonella infections was studied in an island population of a wild marsupial, the quokka (setonix brachyurus), which experiences starvation in summer associated with significant mortality. the frequency of infections was found to vary seasonally over most parts of the island, with high infection rates (70 to 100%) in summer and low infection rates (0 to 30%) in winter. in some samples, there was an average of as many as two isolations per animal, and up to five isolation ...19854004242
the myocardial lesions in the rottnest quokka with nutritional myopathy. 19685709985
a quantitative comparison of the parts of the brains of two australian marsupials and some eutherian mammals.the size and composition of the brains of the quokka wallaby (setonix brachyurus) and the brush-tailed possum (trichosurus vulpecula) were compared with those of the rat, rabbit, cat, sheep, and human. separate structures were taken from the brains by standardized dissection and their weights compared. particular attention was paid to the relationships between the size of the amygdala and other brain structures. marsupials were within the eutherian range in the ratio of whole brain weight to bod ...19817237105
quokkas (setonix brachyurus) demonstrate tactile discrimination learning and serial-reversal learning.two male quokkas (setonix brachyurus: a herbivorous macropod marsupial) were trained to discriminate pairs of stimuli in the laboratory. quokkas indicated their choice by pulling on 1 of 2 simultaneously presented cords. the quokkas' discrimination abilities were tested on 6 tactile and 6 visual discrimination tasks. correct responses were rewarded with food. for both quokkas, all tactile tasks were learned to a criterion of 75% correct in up to 4 20-trial sessions. no visual task maintained cri ...200211930935
development of the lymphoid tissues of the tammar wallaby macropus eugenii.a study has been made of the development of four lymphoid tissues from birth to maturity in the tammar wallaby macropus eugenii--the cervical and thoracic thymus, lymph nodes and gut-associated lymphoid tissue (galt). the development of these tissues in the tammar wallaby is similar to that in two other marsupials, the quokka setonix brachyurus and the virginian opossum didelphis virginiana. lymphocytes were first detected in the cervical thymus of the tammar at day 2 post partum and in the thor ...19979208435
development of the visual cortex in a wallaby--phylogenetic implications.the visual cortex of one of the smallest macropod marsupials, a wallaby, the quokka setonix brachyurus, was examined at maturity and during development from postnatal day 1 to 150 in nissl-stained or golgi-stained sections. injections of horseradish peroxidase into the primary visual centres in adults identified cortical neurons projecting to these regions. the pattern of cell generation was determined by tritiated thymidine/autoradiography. the adult visual cortex was composed of the usual six ...19957796093
configural learning in two species of marsupial (setonix brachyurus and sminthopsis crassicaudata).four experiments examined the ability of quokkas (setonix brachyurus) and fat-tailed dunnarts (sminthopsis crassicaudata) to solve 2 configural tasks: transverse and negative patterning. transverse patterning requires the simultaneous solution of 3 overlapping discrimination problems (a+ b-, b+ c-, c+ a-). both species could solve the nonoverlapping (elemental) version of this task (u+ v-, w+ x-, y+ z-), but only dunnarts solved the transverse patterning task. negative patterning requires condit ...200312856789
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