| development of the urinary system of the marsupial native cat dasyurus hallucatus. | the development of the mesonephros and metanephros was examined in the marsupial northern native cat, dasyurus hallucatus, from birth through to the end of lactation. the mesonephros was present at birth, reached a maximum volume 11 days after birth and had regressed completely by day 30. the metanephros was present on day 2; glomeruli were first seen on day 8, and nephrogenesis continued until day 89 post partum. the newborn native cat is at a very primitive stage of development compared to oth ... | 1992 | 1414201 |
| development of the vestibular and auditory system of the northern native cat, dasyurus hallucatus. | the developing vestibular and auditory system of the native cat dasyurus hallucatus was examined from birth to day 55 postpartum to determine when the six sensory regions had an adult structure. the utricle, a sensory epithelium with an overlying discrete population of otoliths, was present in the newborn native cat. the saccule, which has a similar structure to the utricle, and the three crista ampullaris of the semicircular canals, were present by day 21 postpartum. the organ of corti was form ... | 1992 | 1416092 |
| neurogenesis in the brain auditory pathway of a marsupial, the northern native cat (dasyurus hallucatus). | neurogenesis in the auditory pathway of the marsupial dasyurus hallucatus was studied. intraperitoneal injections of tritiated thymidine (20-40 microci) were made into pouch-young varying from 1 to 56 days pouch-life. animals were killed as adults and brain sections were prepared for autoradiography and counterstained with a nissl stain. neurons in the ventral cochlear nucleus were generated prior to 3 days pouch-life, in the superior olive at 5-7 days, and in the dorsal cochlear nucleus over a ... | 1991 | 1885788 |
| postnatal development of the skin of the marsupial native cat dasyurus hallucatus. | skin development of the northern native cat was examined from birth to weaning at 150 days post partum. an outer layer of cells, termed the periderm or epitrichium, is present on the epidermis of the newborn. this layer of cells is not discernible at 7 days post partum. skin development of the native cat differs from that of the eutherian mammal. the periderm of the eutherian is no longer discernible when the developing hairs first penetrate the epidermis. in the marsupial, this loss of the peri ... | 1990 | 2213886 |
| auditory forebrain organization of an australian marsupial, the northern native cat (dasyurus hallucatus). | structures and connections of auditory forebrain regions of the northern native cat, a member of one of the most primitive families among australian marsupials, have been examined anatomically by using anterograde and retrograde tracing techniques with wheat germ agglutinin-conjugated horseradish peroxidase (wga-hrp) after defining the acoustically responsive neocortical area physiologically. the structure of the medial geniculate body (mg) was similar to that described in other species. the res ... | 1989 | 2464009 |
| functional organization of cerebral microvasculature in a marsupial, the northern quoll (dasyurus hallucatus). | capillaries within the central nervous system (cns) of eutherian mammals form meshworks with numerous anastomoses, whereas capillaries in the cns of marsupials consist entirely of hairpin-like loops, without anastomotic interconnections. counter-current blood flow in capillary loops may have been important in the evolutionary development of a cerebral vascular supply. however, loops are not found in eutherian mammals, perhaps because of a limited benefit to the diffusive conductance of gases. | 1989 | 2769208 |
| vestibular system of the newborn marsupial cat dasyurus hallucatus. | the ultrastructure of the ear of the newborn native cat was examined to determine whether the vestibular system contained sensory receptors. a sensory region, presumably the utricle, was identified in each ear and consisted of a discrete population of otoliths overlying a sensory epithelium which possessed kinocilia and stereocilia. the remainder of the vestibular system did not appear to be developed anatomically. the newborn cat has rudimentary vestibular, olfactory, and mechanoreceptors (merk ... | 1989 | 2817438 |
| brain stem auditory nuclei and their connections in a carnivorous marsupial, the northern native cat (dasyurus hallucatus). | the cytoarchitecture and connections of the brain stem auditory nuclei in the marsupial native cat (dasyurus hallucatus) were studied using nissl material in conjunction with the retrograde transport of horseradish peroxidase injected into the inferior colliculus. some features different from those of eutheria include the disposition of the cochlear nuclear complex medial to the restiform body, a lack of large spherical cells in the anteroventral cochlear nucleus, a small medial superior olive, ... | 1986 | 3036297 |
| the ultrastructure of the pituitary and the adrenal gland of three newborn marsupials (dasyurus hallucatus, trichosurus vulpecula and isoodon macrourus). | the ultrastructure of the pituitary glands of the newborn northern native cat, brushtail possum and the northern brown bandicoot and the adrenal glands of the former two marsupials were examined to determine whether these endocrine glands were functional at birth. the anterior pituitary of all three species was well vascularised and many cells contained electron-dense, membrane bound granules. the adrenal glands were composed of two distinct cell populations. one group of cells possessed dark st ... | 1988 | 3364743 |
| ultrastructural identification of merkel cells around the mouth of the newborn marsupial. | the ultrastructure of the epidermal cells surrounding the mouth of three newborn marsupial species, the northern native cat dasyurus hallucatus, the brush tail possum trichosurus vulpecula and the northern brown bandicoot isoodon macrourus were examined. the presence of merkel cells, highly sensitive touch receptors, would suggest that the sense of touch aids the relatively underdeveloped newborn marsupial to move from the urinogenital sinus to the pouch and to locate the teat. | 1988 | 3364744 |
| afferent input for target survival in marsupial visual development. | the influence of afferent input on the survival of target neurons in mammals has been examined by the removal of one eye of pouch young of the marsupial native cat (dasyurus hallucatus). the ages at eye removal spanned the period of neurogenesis of the ascending visual pathway, and were earlier than the time of maximal axon number in the optic nerve. autoradiography following the injection of tritiated proline into the intact eye of adult animals shows that the lateral geniculate nucleus contral ... | 1988 | 3368116 |
| the ultrastructure of the lung of two newborn marsupial species, the northern native cat, dasyurus hallucatus, and the brushtail possum, trichosurus vulpecula. | the lungs of newborn northern native cats, dasyurus hallucatus and newborn brushtail possums, trichosurus vulpecula were examined by both light and electron microscopy. the native cat has a birth weight of 18 mg after a gestation of about 21 days, whereas the brushtail possum weights 200 mg at birth and has a gestation period of 17.5 days. the lungs of the native cat are two large respiratory sacs, with a respiratory lining of squamous cells and surfactant-secreting cells. the capillaries are lo ... | 1988 | 3396063 |
| frequency representation in the auditory midbrain and forebrain of a marsupial, the northern native cat (dasyurus hallucatus). | the representation of sound frequency was examined in the auditory cortex and inferior colliculus of anaesthetized marsupial native cats (dasyurus hallucatus) using microelectrode mapping techniques. the tonotopic organizations of these two auditory regions are grossly similar to those described in brush-tailed possums and in eutheria. there appears to exist a biased representation of high frequencies (greater than 10khz) in native cats and a paucity of frequencies below 1 khz. unit threshold au ... | 1986 | 3594197 |
| visual acuity of the northern native cat (dasyurus hallucatus)--behavioural and anatomical estimates. | behavioural estimates of the visual acuity of the northern native cat (or northern quoll)--dasyurus hallucatus--were made using the mitchell jumping stand technique. a value of 2.3-2.8 cycles per degree was obtained. this functional acuity compared well with predictions based on the peak ganglion cell density (2600 cells/mm2) determined from the retinal ganglion cell density map. | 1986 | 3790243 |
| the early development of the eye of the pouch-young of the marsupial dasyurus hallucatus. | the development of the eye of the pouch-young of the marsupial native cat dasyurus hallucatus from birth to day 30 is described. following the staging system used by other authors, the stage of development of the eye at birth is comparable to that of a six-week human embryo, a 33 day rhesus embryo or a 14 day rat embryo. in contrast to eutherian mammals where development progresses from one stage to another at approximately the same rate, in the native cat the rate tends to progressively decreas ... | 1987 | 3826661 |
| [studies on the echinonematinae (nematoda)]. | complementary data on the echinonematinae have been obtained by study of "the australian helminth collection, formerly the univeristy of adelaide, department of zoology helminth collection, currently housed in the south australial museum", and by a morphological and biological study of new material. the echinonematinae actually known are the following: -- seurechina chaneeti n. gen., n. sp., parasite of dasyurus hallucatus (west australia) does not have large cephalic hooks but about 50 rings of ... | 1980 | 7458168 |
| the morphological development of the inferior colliculus in a marsupial, the northern quoll (dasyurus hallucatus). | as a part of a project concerning the development of hearing, some features of the morphological development of the inferior colliculus were studied in a marsupial, the northern quoll or native cat (dasyurus hallucatus). marsupials are of particular interest in developmental studies because much embryonic development occurs outside the uterus, in the pouch. nissl-stained material was prepared from pouch-young at various ages between 11 and 81 days, and for a number of adults. four pouch-young we ... | 1994 | 8034786 |
| linstowinema, smales, 1997 (nematoda : seuratidae) from dasyurids (marsupialia : dasyuridae) from australia. | linstowinema edmondsi (echinonematinae) from dasyurus hallucatus (dasyuridae) is redescribed. it can be differentiated from all species of linstowinema occurring in bandicoots (peramelidae) in having the first row of cephalic hooks as long as or longer than the second row. l. gracile n. sp. is described from phascogale tapoatafa and dasycercus cristicauda, and can be distinguished from all previously described species of linstowinema in not having a cuticular dilation of the oesophageal region o ... | 1999 | 10613528 |
| the development of righting reflexes in the pouch young of the marsupial dasyurus hallucatus. | the development of righting was studied in the young of dasyurus hallucatus, a small marsupial from northern australia. young were tested from birth to weaning. righting began at 40 days, when tactile input on the snout triggered rotation to prone. over the next 15-20 days, asymmetrical tactile input on the body triggered righting movements by the hindlegs (and later by the forelegs). vestibular righting reflexes developed after these tactile righting reflexes. furthermore, asymmetrical vestibul ... | 1985 | 1577202 |
| prevalence, genetic diversity and potential clinical impact of blood-borne and enteric protozoan parasites in native mammals from northern australia. | a molecular survey was conducted to provide baseline information on the prevalence, genetic diversity and potential clinical impacts of blood-borne and enteric protozoans in native wild mammals from the northern territory (nt). a total of 209 blood and 167 faecal samples were collected from four target species; the northern brown bandicoot (isoodon macrourus), common brushtail possum (trichosurus vulpecula), northern quoll (dasyurus hallucatus) and brush-tailed rabbit-rat (conilurus penicillatus ... | 2017 | 28408215 |
| comparative physiology of australian quolls (dasyurus; marsupialia). | quolls (dasyurus) are medium-sized carnivorous dasyurid marsupials. tiger (3,840 g) and eastern quolls (780 g) are mesic zone species, northern quolls (516 g) are tropical zone, and chuditch (1,385 g) were once widespread through the australian arid zone. we found that standard physiological variables of these quolls are consistent with allometric expectations for marsupials. nevertheless, inter-specific patterns amongst the quolls are consistent with their different environments. the lower t (b ... | 2010 | 20217094 |
| organization of somatosensory cortex in three species of marsupials, dasyurus hallucatus, dactylopsila trivirgata, and monodelphis domestica: neural correlates of morphological specializations. | the organization of somatosensory neocortex was investigated in three species of marsupials, the northern quoll (dasyurus hallucatus), the striped possum (dactylopsila trivirgata), and the short-tailed opossum (monodelphis domestica). in these species, multiunit microelectrode mapping techniques were used to determine the detailed organization of the primary somatosensory area (si). in the striped possum and quoll, the topography of somatosensory regions rostral (r), and caudal (c) to si were de ... | 1999 | 10075440 |
| manganese accumulates in the brain of northern quolls (dasyurus hallucatus) living near an active mine. | mining is fundamental to the australian economy, yet little is known about how potential contaminants bioaccumulate and affect wildlife living near active mining sites. here, we show using air sampling that fine manganese dust within the respirable size range is found at levels exceeding international recommendations even 20 km from manganese extraction, processing, and storage facilities on groote eylandt, northern territory. endangered northern quolls (dasyurus hallucatus) living near mining s ... | 2018 | 29096311 |
| running faster causes disaster: trade-offs between speed, manoeuvrability and motor control when running around corners in northern quolls (dasyurus hallucatus). | movement speed is fundamental to all animal behaviour, yet no general framework exists for understanding why animals move at the speeds they do. even during fitness-defining behaviours like running away from predators, an animal should select a speed that balances the benefits of high speed against the increased probability of mistakes. in this study, we explored this idea by quantifying trade-offs between speed, manoeuvrability and motor control in wild northern quolls (dasyurus hallucatus) - a ... | 2015 | 25653423 |
| acrosomal integrity, viability, and dna damage of sperm from dasyurid marsupials after freezing or freeze drying. | dasyurids are a diverse group of australian native carnivores and insectivores that contains several threatened species. despite successful cryopreservation of sperm from several marsupials, only 3% postthaw motility is reported for dasyurid marsupials. this study examined sperm preservation in the fat-tailed dunnart (sminthopsis crassicaudata), an experimental model, with supplementary observations on the eastern quoll (dasyurus viverrinus) and northern quoll (dasyurus hallucatus). in s. crassi ... | 2009 | 19616836 |
| acrosome stability in the spermatozoa of dasyurid marsupials. | the spermatozoa of most marsupials lack nuclear stabilising disulfide-bonded protamines found in eutherian mammals. however, disulfide stabilisation has been observed in the acrosome of macropodid (macropus eugenii) and phalangerid (trichosurus vulpecula) marsupials. as a result this organelle, which is normally fragile in eutherian mammals, is robust and able to withstand physical and chemical challenge in these marsupials. the present study examined acrosomal characteristics of the spermatozoa ... | 2008 | 18255019 |
| combined mitochondrial and nuclear dna sequences resolve the interrelations of the major australasian marsupial radiations. | australasian marsupials include three major radiations, the insectivorous/carnivorous dasyuromorphia, the omnivorous bandicoots (peramelemorphia), and the largely herbivorous diprotodontians. morphologists have generally considered the bandicoots and diprotodontians to be closely related, most prominently because they are both syndactylous (with the 2nd and 3rd pedal digits being fused). molecular studies have been unable to confirm or reject this syndactyla hypothesis. here we present new mitoc ... | 2006 | 16507529 |
| semelparity in a large marsupial. | complete mortality of males after mating is known in several small dasyurid and didelphid species (up to 300g) and has previously been suggested to be a consequence of their small size and their inability to sequester sufficient fat reserves for an intense rut in the winter. males of these species use increased corticosteroid levels to allow protein catabolism, enabling them to support their mating effort with other body reserves. however, increased corticosteroid levels have negative consequenc ... | 2001 | 11270438 |
| organization of visual cortex in the northern quoll, dasyurus hallucatus: evidence for a homologue of the second visual area in marsupials. | two visual areas, v1 and v2 (first and second visual areas), appear to be present in the posterior neocortex of all eutherian mammals investigated so far. however, previous studies have not established whether an area homologous to v2 also exists in metatherian mammals (marsupials). using electrophysiological techniques, we mapped the visual receptive fields of neurons in the striate and peristriate cortices of the northern quoll, an australian marsupial. we found that neurons in a 2-mm-wide str ... | 1999 | 10103084 |
| development of hearing and vocalization in a marsupial, the northern quoll, dasyurus hallucatus. | the development of hearing was studied in the northern quoll, a nocturnal marsupial carnivore whose young are born into a pouch in an immature state after about 21 days in utero. startle responses to noise bursts of 105 db sound pressure level first appeared at 60 days after arrival in the pouch, but only to occasional stimuli; forelimb rather than whole body twitches were evoked. the latter were elicited regularly at 67 days onward. auditory brainstem response (abr) audiograms were measured dur ... | 1996 | 8986045 |
| features of the structural development of the inferior colliculus in relation to the onset of hearing in a marsupial: the northern quoll, dasyurus hallucatus. | the time course of synaptogenesis and the arrival and myelination of afferent connections were studied in the developing inferior colliculus (ic) of a marsupial, the northern quoll, and related to the onset of hearing and patency of peripheral auditory structures in that species. the quoll is born after 3 weeks of intrauterine growth and completes its development in a pouch for a further 80 days before weaning. synaptic terminals in the ic at 9 days after arrival in the pouch were extremely rare ... | 1996 | 8913894 |
| hearing, vocalization and the external ear of a marsupial, the northern quoll, dasyurus hallucatus. | as part of a continuing study of the development of the marsupial auditory system, auditory brainstem responses (abr) were recorded and an abr audiogram was constructed for five female northern quolls (dasyurus hallucatus), which are nocturnal carnivores. the best frequency for hearing lies between 8 and 10 khz, and at 50 db spl there is a range from about 0.5 to 40 khz. vocalizations of adult quolls and pouch-young were recorded with a digital audio tape recorder, and the power spectra of repre ... | 1994 | 7852631 |
| developmental staging in a marsupial dasyurus hallucatus. | in a marsupial, dasyurus hallucatus, pouch-young of various ages from newborn to 55 days were embedded in wax and serially sectioned. on the basis of the relative development of external and internal characteristics, they were placed in the carnegie staging system developed by streeter and elaborated by o'rahilly and associates. birth occurred at stage 15, and the end of embryogenesis (stage 23) was reached about day 33. whereas stage 23 is characterised in all eutherians by the closure of the s ... | 1992 | 1609962 |
| skull shape of a widely distributed, endangered marsupial reveals little evidence of local adaptation between fragmented populations. | the biogeographic distribution of diversity among populations of threatened mammalian species is generally investigated using population genetics. however, intraspecific phenotypic diversity is rarely assessed beyond taxonomy-focused linear measurements or qualitative descriptions. here, we use a technique widely used in the evolutionary sciences-geometric morphometrics-to characterize shape diversity in the skull of an endangered marsupial, the northern quoll, across its 5,000 km distribution r ... | 2020 | 33005341 |
| greater agility increases probability of survival in the endangered northern quoll. | introduced predators combined with habitat loss and modification are threatening biodiversity worldwide, particularly the 'critical weight range' (cwr) mammals of australia. in order to mitigate the impacts of invasive predators on native species in different landscapes, we must understand how the prey's morphology and performance determine their survival. here, we evaluated how phenotypic traits related to escape performance predict the probability of survival for an endangered cwr mammal, the ... | 2020 | 32561634 |
| moving in complex environments: a biomechanical analysis of locomotion on inclined and narrow substrates. | characterisation of an organism's performance in different habitats provides insight into the conditions that allow it to survive and reproduce. in recent years, the northern quoll (dasyurus hallucatus) - a medium-sized semi-arboreal marsupial native to northern australia - has undergone significant population declines within open forest, woodland and riparian habitats, but less so in rocky areas. to help understand this decline, we quantified the biomechanical performance of wild northern quoll ... | 2019 | 30814297 |
| how many and when? optimising targeted gene flow for a step change in the environment. | targeted gene flow is an emerging conservation strategy that involves introducing individuals with particular traits to places where these traits are of benefit. one obvious application is to adapt a recipient population to a known threat, but questions remain as to how best to achieve this. here, we vary timing and size of the introduction to maximise our objective - survival of the recipient population's genome. we explore a generic population model as well as a specific example - the northern ... | 2019 | 30618109 |
| cloacal and ocular microbiota of the endangered australian northern quoll. | 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 sam ... | 2018 | 30002322 |
| targeted gene flow and rapid adaptation in an endangered marsupial. | targeted gene flow is an emerging conservation strategy. it involves translocating individuals with favorable genes to areas where they will have a conservation benefit. the applications for targeted gene flow are wide-ranging but include preadapting native species to the arrival of invasive species. the endangered carnivorous marsupial, the northern quoll (dasyurus hallucatus), has declined rapidly since the introduction of the cane toad (rhinella marina), which fatally poisons quolls that atta ... | 2019 | 29896894 |
| the perils of paradise: an endangered species conserved on an island loses antipredator behaviours within 13 generations. | when imperilled by a threatening process, the choice is often made to conserve threatened species on offshore islands that typically lack the full suite of mainland predators. while keeping the species extant, this releases the conserved population from predator-driven natural selection. antipredator traits are no longer maintained by natural selection and may be lost. it is implicitly assumed that such trait loss will happen slowly, but there are few empirical tests. in australia, northern quol ... | 2018 | 29875211 |
| manganese contamination affects the motor performance of wild northern quolls (dasyurus hallucatus). | neuromotor deficits are an important sign of manganese (mn) toxicity in humans and laboratory animals. however, the impacts of mn exposure on the motor function of wild animals remains largely unknown. here, we assessed the impact of chronic exposure to mn from active mining operations on groote eylandt, australia on the motor function of the semi-arboreal northern quoll (dasyurus hallucatus), an endangered species. the three motor tests conducted-maximum sprint speed on a straight run, manoeuvr ... | 2018 | 29793108 |