ORCID Profile
0000-0003-1739-6593
Current Organisation
University of Adelaide
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Publisher: Australian Museum
Date: 25-11-2020
Publisher: Springer Science and Business Media LLC
Date: 1990
DOI: 10.1007/BF00297226
Publisher: CSIRO Publishing
Date: 2000
DOI: 10.1071/ZO00009
Abstract: The macromorphology of the ductuli efferentes and epididymis of the koala (Phascolarctos cinereus) was investigated and found to differ from that of other marsupial species that have been described as it comprised four macroscopically distinct lobes. Light and electron microscopy of epithelium of the duct within these lobes showed that there were principal and ciliated cells lining the duct of the first lobe, indicating it to be composed of ductuli efferentes. In the other three lobes, the epithelium contained principal, basal, electron-lucent, and mitochondria-rich cells, showing that these three lobes included the epithelium of the epididymis. The height of this epithelium gradually increased along the duct (contrary to the situation in most other species that have been studied, in which a decrease occurs). Preliminary 1D-SDS PAGE observations of flushes from the caput and cauda epididymides suggested that epididymal proteins were secreted along much of the length of the duct the greater height of the cauda epithelium may relate to the greater protein synthetic and secretory activity in this region.
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/RD9960645
Abstract: In the dasyurid marsupial Sminthopsis crassicaudata, the shell membrane of cleaving embryos has a compact granular structure but becomes fibrous around blastocysts. Polyclonal antibodies were raised against the extracellular coats, mucoid and shell membrane, of oocytes and early embryos. Immunogold cytochemistry resulted in labelling of secretory granules in the epithelia of both the ulla and isthmus of the oviduct, although the secretory granules of these two regions differed in their ultrastructural appearance. Those in the ulla were heterogeneous with areas of varying electron density, whereas those in the isthmus were electron dense and homogeneous. Shell membrane precursors were found in secretory granules in the epithelia of the uterotubal junction and endometrial glands and were electron lucent.
Publisher: Wiley
Date: 12-1995
Publisher: Elsevier BV
Date: 12-1976
Publisher: CSIRO Publishing
Date: 1994
DOI: 10.1071/RD9940485
Abstract: Australian marsupials exhibit a wide range of variation in sperm head morphology, and in thickness of the zona pellucida around the oocyte, suggesting interspecfic differences in the processes of sperm-egg interaction. The observations described here are largely based on the dasyurid Sminthopsis crassicaudata. They show that in oestrous females, after mating, a coagulum forms in the lateral vaginae and, within an hour of insemination, numerous spermatozoa congregate in the isthmus of the oviduct in which the vanguard population undergoes transformation with the head rotating on its axis with the tail to form a T-shape. Once oocytes are released, a few spermatozoa migrate to the higher reaches of the oviduct where sperm-zona binding occurs by way of the plasmalemma over the acrosomal region. The acrosome reaction takes place here and, as the egg rotates, the tail of the spermatozoon becomes parallel to the head. A small region of acrosome sometimes appears to remain intact at this time because spermatozoa with partly intact acrosomes have been found within the zona matrix. In some of these, electron-dense bridges between part of the inner and outer acrosomal membranes which may act as stabilizing structures, were also seen. The zona matrix is tightly packed around the penetrating spermatozoon, but that close to the acrosomal region becomes less electron-dense and more filamentous. Once incorporated into the egg, the spermatozoon lacks a cell membrane around the tail but vesicles close to the sperm head may, at least in part, be remnants of an inner acrosomal membrane. How generally applicable these observations are to other Australian marsupials remains to be determined.
Publisher: Wiley
Date: 1983
Publisher: CSIRO Publishing
Date: 2013
DOI: 10.1071/ZO13049
Abstract: Oxalate nephrosis is a leading disease of the Mount Lofty Ranges koala population in South Australia, but the cause is unclear. In other herbivorous species, a common cause is high dietary oxalate therefore this study aimed to determine the oxalate content of eucalypt leaves. Juvenile, semimature and mature leaves were collected during spring from eucalypt species eaten by koalas in the Mount Lofty Ranges and compared with those from Moggill, Queensland, where oxalate nephrosis has lower prevalence. Total oxalate was measured as oxalic acid by high-performance liquid chromatography. The oxalate content of eucalypts was low ( % dry weight), but occasional Mount Lofty leaf s les had oxalate levels of 4.68–7.51% dry weight. Mount Lofty eucalypts were found to be higher in oxalate than those from Queensland (P 0.001). In conclusion, dietary oxalate in eucalypt leaves is unlikely to be the primary cause of oxalate nephrosis in the Mount Lofty koala population. However, occasional higher oxalate levels could cause oxalate nephrosis in in idual koalas or worsen disease in those already affected. Further studies on the seasonal variation of eucalypt leaf oxalate are needed to determine its role in the pathogenesis of oxalate nephrosis in koalas.
Publisher: Wiley
Date: 05-05-2011
DOI: 10.1002/JMOR.10955
Abstract: This study describes the morphology of the spermatozoon from the cauda epididymidis of representative members of two squirrel subfamilies, the Sciurinae and Callosciurinae, as determined by fluorescent, scanning, and transmission electron microscopy. All species examined possess a massive apical segment of the sperm acrosome. It varied markedly in the extent of its caudal flexion but was always much larger, and more complex, than that of the spermatozoon of most other rodents so far documented, although somewhat similar to that of some hystricomorph species. Because this sperm form appears to be present within at least two of the three major living clades of Rodentia, it is possible that it is the ancestral condition within this mammalian order.
Publisher: Elsevier BV
Date: 07-1973
DOI: 10.1016/0002-9378(73)91008-9
Abstract: Mycoplasma bovis is a cause of pneumonia, mastitis, arthritis and otitis media in cattle throughout the world. However, despite its clinical significance, there is a paucity of tools to genetically manipulate it, impeding our capacity to further explore the molecular basis of its virulence. To address this limitation, we developed a series of homologous and heterologous replicable plasmids from M. bovis and M. agalactiae. The shortest replicable oriC plasmid based on the region downstream of dnaA in M. bovis was 247 bp and contained two DnaA boxes, while oriC plasmids based on the region downstream of dnaA in M. agalactiae strains 5632 and PG2 were 219 bp and 217 bp in length, respectively, and contained only a single DnaA box. The efficiency of transformation in M. bovis and M. agalactiae was inversely correlated with the size of the oriC region in the construct, and, in general, homologous oriC plasmids had a higher transformation efficiency than heterologous oriC plasmids. The larger pWholeoriC45 and pMM21-7 plasmids integrated into the genomic oriC region of M. bovis, while the smaller oriC plasmids remained extrachromosomal for up to 20 serial passages in selective media. Although specific gene disruptions were not be achieved in M. bovis in this study, the oriC plasmids developed here could still be useful as tools in complementation studies and for expression of exogenous genes in both M. bovis and M. agalactiae.
Publisher: Bioscientifica
Date: 07-1976
Publisher: Wiley
Date: 08-1986
Publisher: CSIRO Publishing
Date: 1995
DOI: 10.1071/RD9951141
Abstract: The number, distribution, maturation, motility and ultrastructure of spermatozoa from both northern (Isoodon macrourus) and southern (Isoodon obesulus) brown bandicoots were examined. One epididymidis per animal was fixed for light microscopy and transmission electron microscopy, and the contralateral side was used for the determination of sperm number, distribution and motility. Sperm form was similar between the two species. Approximately 56 x 10(6) testicular sperm and 100 x 10(6) epididymal sperm per side were present in I. macrourus, about 60% of which were in the caudal region. Initiation of sperm nuclear rotation and loss of the cytoplasmic droplet was first observed in distal caput or proximal corpus segments along with slow progressive motility. In these sperm, dislocation and anterior movement of the sperm neck from the implantation fossa and the modification of the distal margins of the sperm acrosome were evident. Motility of cauda epididymidal spermatozoa was rapid and coordinated, movement was restricted to one plane, and lateral head displacement was marked. As media viscosity increased, sperm velocity decreased, as did the litude of the tail beat, its frequency, and lateral head displacement but, in viscous mineral oil and mixtures of media and prostatic exudate, extremely rapid sinusoidal motility occurred. This study has detailed unusual morphological changes in bandicoot sperm during epididymal maturation and has shown that, although bandicoot sperm differ morphologically from those of the dasyurids, particularly in relation to head-tail orientation and tail ultrastructure, they exhibit similar motility.
Publisher: Bioscientifica
Date: 05-2000
Abstract: The zona pellucida glycoconjugate content of several marsupial species was investigated using differential lectin histochemistry. Ovaries from fat-tailed dunnarts, a southern brown bandicoot, grey short-tailed opossums, brushtail possums, ringtail possums, koalas and eastern grey kangaroos were fixed, embedded in paraffin wax, sectioned and stained with ten fluorescein isothiocyanate-conjugated lectins. Sections were also incubated with either neuraminidase or saponified, respectively, before incubation with the lectins to identify saccharide residues masked by sialic acids or O-acetyl groups on sialic acids. The zonae pellucidae surrounding the oocytes of the marsupials demonstrated interspecific variation in glycoconjugate content, with mannose-containing glycoconjugates exhibiting the greatest variation. Some of the zona pellucida glycoconjugates of all species, except those of the opossums, were masked by sialic acid with an increase in fluorescence with lectins from Arachis hypogea (PNA), and Glycine max (SBA), after desialylation. The disaccharide beta-galactose(1-4)N-acetyl-D-glucosamine appeared to be conformationally masked by O-acetyl groups of sialic acids in the zonae pellucidae of all species, with an increase in fluorescence with the lectin from Erythrina cristagalli (ECA), after saponification. Similar intensity and localization of beta-(1-4)-N-acetyl-D-glucosamine, as shown by staining of the lectin from Triticum vulgaris (WGA), to the inner and outer regions of the zona pellucida, were found to those reported in eutherian species. WGA fluorescence became uniform throughout the zonae pellucidae after saponification, indicating differential O-acetylation of sialic acids on the internal compartment of the zonae pellucidae.
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/RD13395
Abstract: This study investigated the effects of high temperatures on male germ cell development and epididymal sperm motility of laboratory mice. In Experiment 1, adult males (n = 16) were exposed to whole-body heat of 37–38°C for 8 h day–1 for 3 consecutive days, whereas controls (n = 4) were left at 23–24°C. In Experiment 2, adult mice (n = 6) were exposed to 37–38°C for a single 8-h period with controls (n = 6) left at 23–24°C. Experiment 2 was conducted as a continuation of previous study that showed changes in spermatozoa 16 h after exposure to heat of 37–38°C for 8 h day–1 for 3 consecutive days. In the present study, in Experiment 1, high temperature reduced testes weights 16 h and 14 days after exposure, whereas by Day 21 testes weights were similar to those in the control group (P = 0.18). At 16 h, 7 and 14 days after exposure, an increase in germ cell apoptosis was noticeable in early and late stages (I–VI and XI–XII) of the cycle of the seminiferous epithelium. However, apoptosis in intermediate stages (VII–X) was evident 16 h after heat exposure (P 0.05), without any change at other time periods. By 21 days, there were no significant differences between heat-treated groups and controls. Considerably more caspase-3-positive germ cells occurred in heat-treated mice 16 h after heat exposure compared with the control group (P 0.0001), whereas 8 h after heat in Experiment 2, sperm motility was reduced with a higher percentage of spermatozoa showing membrane damage. In conclusion, the present study shows that whole-body heat of 37–38°C induces stage-specific germ cell apoptosis and membrane changes in spermatozoa this may result in reduced fertility at particular times of exposure after heating.
Publisher: Bioscientifica
Date: 09-1991
Abstract: Hopping mice have extremely small testes and a reduced complement of male accessory sex glands. Nevertheless, greater than 1000 spermatozoa populate the isthmus of the oviduct after each insemination and a range of morphological types is found similar to that in the male tract. When females are primed with gonadotrophins they sometimes lock with more than one of the males within the group and in the present study two inseminations sometimes took place at the one oestrus. There is thus the possibility for intermale sperm competition within the female tract of these animals.
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/ZO9920013
Abstract: This study was carried out as part of a broader investigation into the factors that determine interspecific variation in testis size amongst conilurine rodents. The hypothesis proposed is that the huge differences in absolute and relative testis size between the spinifex hopping mouse (Notomys alexis) and the plains rat (Pseudomys australis) relate to differences in breeding system. One aspect of a species' breeding system, the capacity for multiple paternity, was assessed under laboratory conditions for each species. Allozyme markers were used to set up appropriate trios consisting of one female cohabiting with two mates of different genotypes and to assess the paternity of the resultant pups that were born. Multiple paternity within a single litter was not recorded for hopping mice but was observed occasionally in plains rats, a result consistent with the hypothesis under test.
Publisher: Wiley
Date: 14-12-2013
DOI: 10.1002/JMOR.20236
Abstract: Most species in the three highly speciose families of the mouse-related clade of rodents, the Muridae, Cricetidae, and Nesomyidae (superfamily Muroidea), have a highly complex sperm head in which there is an apical hook but there are few data available for the other related families of these rodents. In the current study, using light and electron microscopies, we investigated the structure of the spermatozoon in representative species of four other families within the mouse-related clade, the Dipodidae, Spalacidae, Pedetidae, and Heteromyidae, that erged at or near the base of the muroid lineage. Our results indicate that a erse array of sperm head shapes and tail lengths occurs but none of the species in the families Spalacidae, Dipodidae, or Pedetidae has a sperm head with an apical hook. By contrast, a rostrally extending apical hook is present in spermatozoa of members of the Family Heteromyidae which also invariably have comparatively long sperm tails. These findings suggest that the hook-shaped sperm head in the murid, cricetid, and nesomyid rodents evolved after ergence of this lineage from its common ancestor with the other families of the mouse-related clade, and that separate, and independent, convergent evolution of a similar sperm head form, and long sperm tail, occurred in the Heteromyidae.
Publisher: CSIRO Publishing
Date: 1979
DOI: 10.1071/ZO9790177
Abstract: In the male hopping-mouse, spermatozoa first appeared in seminiferous tubules on day 60 and were present in the epididymis a few days later ventral prostates markedly increased in weight between days 56 and 60. Some females had large Graafian follicles, stimulated uteri and perforate vaginae on day 40 corpora lutea were first observed on day 44, but most females did not spontaneously ovulate until after day 54. Gestation in post-partum mated, non-suckling females lasted about 32 days, with implantation on day 7 or 8. When four or more young were suckling, gestation increased to 39 days (mean) implantation took place between days 11-13 and 14-17 when there were either three or four, or five, suckling young respectively. From one to three unfertilized oocytes surrounded by cumulus cells were found in the Fallopian tubes between days 7 and 17 in some pregnant females. Post partum, the most common ovulation rate and litter size was 4 72% of these litters fully survived to weaning 10-15% of litters were of five or six young and nearly half of these fully survived to weaning in the natural environment litters were of four or five young. Without post-partum mating and without suckling young, females had ovulated spontaneously by days 9-11. Significantly fewer females suckling from four to six young had oocytes at this time, but the percentage had increased by days 15-18. This indicates a delay, but not prevention, of spontaneous ovulation during lactation. Field-caught females from the southern Northern Territory were reproductively inactive on three out of four occasions. The fourth time, when there had been 50 mm of rain in the preceding few weeks, all adult females caught had corpora lutea and some were pregnant. Greatest ovarian inhibition coincided with high population density. When compared to data for small northern temperate-zone rodents, most of the above reproductive parameters do not indicate a high reproductive rate, but data for closely related, apparently non-cyclic, Australian species appear to be similar except for, possibly, age of puberty and spontaneous ovulation during lactation. The significance of these results to r-strategy in this species is discussed.
Publisher: Elsevier BV
Date: 06-2007
DOI: 10.1016/J.ANIREPROSCI.2006.06.011
Abstract: This study investigates the effect of three exogenous gonadotrophin regimens on ovarian follicular development in southern hairy-nosed wombats during the non-breeding season. Females were given either porcine follicle stimulating hormone (pFSH total of 200 mg at 12 h intervals over 7 (Group 1), or 4 days (Group 2)), or pregnant mares' serum gonadotrophin (PMSG single dose of 150 I.U. (Group 3)). In all treatment groups 25 mg of porcine luteinising hormone (pLH) was used to trigger maturation Groups 1 and 2 received pLH 12 h after the final pFSH injection and Group 3 received pLH 72 h after PMSG. The results showed Group 1 produced significantly more follicles per ovary (5.91+/-1.28) than Group 2 (1.67+/-0.62), or Group 3 (2.17+/-1.16) at p<0.05. Control females received saline injections concurrently with the three treatment groups (n=6 2 control animals for each treatment group). No follicular development occurred in any control female. Analysis of oocyte nuclear status revealed that while oocytes from all three treatment groups had resumed meiosis, only those in Group 1 (7-day pFSH LH treatment) progressed to metaphase II. These results have implications for the development of assisted breeding strategies in this species.
Publisher: Wiley
Date: 19-04-2007
Publisher: Oxford University Press (OUP)
Date: 04-1994
DOI: 10.1095/BIOLREPROD50.4.845
Abstract: The disposition of spermatozoa in the female tract of the dasyurid marsupial, Sminthopsis crassicaudata, was examined before and after ovulation, by transillumination using differential interference optics. At 6-30 h after mating in females with maturing follicles, spermatozoa were restricted to special storage crypts that define the isthmus of the Fallopian tube. These spermatozoa were mostly immotile and were spear shaped, except for 50-200 vanguard spermatozoa within anterior crypts that were T shaped due to a rotation of the head on the tail. After ovulation and arrival of eggs in the narrow upper ovarian segment of the tube, several hundred isthmic spermatozoa migrated to that region, dispersed singly or in small groups of variable motility with some festooned around eggs. Most clearly displayed a T configuration, and subsequently, those remaining in the isthmic crypts also adopted a T shape in situ. The motility of mature epididymal spermatozoa and of those flushed from the isthmus before and after ovulation was similar in vitro, and all were spear shaped except for some T-shaped isthmic spermatozoa recovered after ovulation. However, neither spear- nor T-shaped active isthmic spermatozoa ever adhered to the zona pellucida when incubated with eggs. We conclude that transport to and storage of spermatozoa in the isthmus of the Fallopian tube, and their later migration up to the fertilization site and coincident transformation to a T shape, all are closely regulated by the ovarian follicular cycle in Sminthopsis. Only on reaching the upper ovarian segment of the Fallopian tube do Sminthopsis spermatozoa appear to be able to bind to the egg, when the T shape brings the whole surface area of the acrosome into apposition with the zona pellucida. These observations are discussed with special reference to sperm capacitation, sperm penetration mechanisms, and the different idiosyncratic designs of the sperm head in marsupial and eutherian mammals, respectively.
Publisher: CSIRO Publishing
Date: 1983
DOI: 10.1071/ZO9830313
Abstract: Scanning electron microscopy of the sperm head of the hopping-mouse indicates considerable variability in shape, much of which is probably due to the fragility of the acrosome. However, fluorescence microscopy of the sperm after staining with 4'-6-diamidino-2-phenylindole (DAPI) indicates some nuclear variability as well. Such polymorphism in sperm head morphology is unusual in mammals its functional significance remains to be determined.
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/AM10034
Abstract: This study aimed to determine the home range and movement patterns of Petrogale lateralis in the arid-zone Anangu Pitjantjatjara Yankunytjatjara Lands in the north-west of South Australia. Ten Global Positioning System radio-collars were attached to animals, with collars programmed to function in 2008–09. Catastrophic collar failure resulted in only 28 days of data, from July 2008, being retrieved from one adult female. During this time, the female occupied a 90% kernel range of 57.9 ha and core (50%) range of 9.3 ha. The animal moved a total of 50.8 km and undertook three journeys of over 1 km. The longest of these was 1.2 km, undertaken in 89 min. The high mobility of the study animal has implications for management, particularly predator baiting and fire management strategies. Future research should assess the validity of these results by increasing s le size and conducting similar work for other arid-zone P. lateralis. The lessons learnt from the current GPS collar deployment may also be of interest to other researchers.
Publisher: Elsevier BV
Date: 1982
Publisher: Cambridge University Press (CUP)
Date: 08-1999
DOI: 10.1017/S0967199499000623
Abstract: The zona pellucida (ZP) is an extracellular glycoprotein coat that is deposited around the oocyte during folliculogenesis and performs several functions that relate to fertilisation and preimplantion development. In eutherian mammals it consists of three major glycoproteins – ZPA, ZPB, and ZPC – but little is known about its molecular constitution in marsupials. We have isolated the cDNA encoding the ZPA homologue in two distantly related marsupial series: the possum, Trichosurus vulpecula (a phalangerid) and the dunnart Sminthopsis crassicaudata (a dasyurid). The two cDNA sequences were 86% identical and showed extensive regions of homology to eutherian ZPA proteins, particularly in the central region of the molecule. Many other features of the ZPA protein, except the positioning of the N -linked glycosylation sites, were also conserved between marsupials and eutherians. ZPA expression was shown to occur maximally in the cytoplasm of the oocyte primary follicles with a little, but significant, expression in oocytes of both primordial follicles and in the cytoplasm of the oocyte in follicles with an antral cavity. No expression was seen in surrounding follicle or granulosa cells
Publisher: Wiley
Date: 2007
DOI: 10.1002/JMOR.10544
Abstract: The structural organization of the spermatozoon from the Eurasian beaver, Castor fiber (Family: Castoridae), was determined and compared to that of other sciuromorph rodents. The beaver spermatozoon has a head, which is variable in form but usually paddle-shaped, with a small nucleus and very large acrosome, and a tail that is relatively short compared to that of most other rodents. Transmission electron microscopy indicates that in most testicular spermatozoa the acrosome projects apically, although in a few it becomes partly flexed. During the final stages of maturation, however, the acrosome becomes highly folded so that the apical segment comes to lie alongside part of the acrosome that occurs lateral to the nucleus, with, in some cases, fusion taking place between the outer acrosomal membranes. The sperm nucleus is wedge-shaped, being broader basally and narrowing apically with an occasional large nuclear vacuole occurring. This spermatozoon structure is markedly different from that found in the other species of Geomyoidea, which is the sister group of the Castoridae. The findings thus emphasize the highly ergent nature of the beaver spermatozoon and demonstrate that, within the proposed Infraorder Castorimorpha, very large differences in sperm structure have evolved.
Publisher: Bioscientifica
Date: 07-2001
Abstract: Variation in localization and distribution of saccharides on the sperm surface of a marsupial, the brushtail possum, Trichosurus vulpecula, was compared between spermatozoa from the caput and cauda epididymides. Spermatozoa were subjected to the following treatments: (i) unfixed and fixed spermatozoa were stained with fluorescein-labelled lectins (ii) unfixed spermatozoa were incubated with lectins for determination of agglutination and (iii) spermatozoa were incubated with detergent to remove the plasmalemma, the glycoproteins were separated on SDS-PAGE and western blots were stained with biotinylated lectins. Many of the fluorescein isothiocyanate (FITC)-labelled lectins bound selectively to the sperm surface, and marked differences were found in lectin staining affinity between caput and cauda epididymal spermatozoa. Incubation of spermatozoa from the cauda epididymidis with neuraminidase reversed many of the differences in staining of the cauda epididymal spermatozoa, indicating masking of some terminal saccharides by sialic acid. Agglutination of spermatozoa from the caput epididymidis occurred after incubation with Concanavalin A (ConA) and soybean agglutinin (SBA), but agglutination was less extensive for spermatozoa from the cauda epididymidis. Western blot analysis indicated several ConA-positive bands in caput sperm extracts, but fewer positive bands in the cauda sperm extracts, whereas SBA stained four bands from caput but none from the cauda epididymal spermatozoa. These results demonstrate extensive glycosylation of the surface proteins of spermatozoa from the caput epididymidis and significant differences in spermatozoa from the cauda epididymidis. In general, the findings indicate similar glycosylation of the surface of marsupial spermatozoa to those from eutherian mammals despite marked differences in their morphology and early ergence of marsupials from eutherian mammals. It would appear that this situation differs markedly from that in sub-mammalian vertebrates.
Publisher: Wiley
Date: 11-1997
DOI: 10.1002/(SICI)1098-2795(199711)48:3<367::AID-MRD10>3.0.CO;2-T
Publisher: Bioscientifica
Date: 10-1970
Abstract: Chronic nonhealing venous leg ulcers (VLUs) are widespread and debilitating, with high morbidity and associated costs about $15 billion is spent annually on the care of VLUs in the United States. Despite this, there is a paucity of treatments for VLUs because of the lack of pathophysiologic insight into ulcer development as well as the lack of knowledge regarding biologic actions of existing VLU-targeted therapies. The bioengineered bilayered living cellular construct (BLCC) skin substitute is a U.S. Food and Drug Administration-approved biologic treatment for healing VLUs. To elucidate the mechanisms through which the BLCC promotes healing of chronic VLUs, we conducted a clinical trial (NCT01327937) in which patients with nonhealing VLUs were treated with either standard of care (compression therapy) or the BLCC together with standard of care. Tissue was collected from the VLU edge before and 1 week after treatment, and the s les underwent comprehensive microarray mRNA and protein analyses. Ulcers treated with the BLCC skin substitute displayed three distinct transcriptomic patterns, suggesting that BLCC induced a shift from a nonhealing to a healing tissue response, involving modulation of inflammatory and growth factor signaling, keratinocyte activation, and attenuation of Wnt/β-catenin signaling. In these ways, BLCC application orchestrated a shift from the chronic nonhealing ulcer microenvironment to a distinctive healing milieu resembling that of an acute, healing wound. Our findings provide in vivo evidence in VLU patients of pathways that can be targeted in the design of new therapies to promote healing of chronic VLUs.
Publisher: Informa UK Limited
Date: 1981
DOI: 10.3109/01485018108999331
Abstract: In the hopping mouse, Notomys alexis, there are very small testes and relatively low numbers of spermatozoa in the extragonadal ducts. Large ventral prostates are present, but the seminal vesicles, coagulating glands, ullaries, and dorsal prostates are all extremely small, although their histological structure and secretory activity is similar to that of the laboratory murids. Bulbourethrals are typical, but the preputials are very small and composed of sebaceous secretory units and an associated hair follicle. The possible functional significance of these findings is briefly discussed.
Publisher: Bioscientifica
Date: 05-1987
Abstract: Absolute and relative testis mass of two species of conilurine rodents, the plains rat (Pseudomys australis) and the hopping mouse (Notomys alexis), were markedly different. In plains rats the testis comprised approximately 3% of body mass while in hopping mice they rarely accounted for more than 0.2%. In both species, 8 cellular associations, or cycle stages, were recognized in the seminiferous epithelium. The relative frequencies, and hence durations, of Stages I to VIII were 5.1, 7.0, 12.5, 10.5, 5.4, 25.9, 4.4 and 29.0% of one cycle for plains rats (N = 14), and 20.4, 10.9, 9.6, 8.1, 5.1, 20.4, 14.7 and 10.8% for laboratory-bred hopping mice (N = 35). Generally, the relative durations of the cycle stages were very similar between plains rat in iduals, but were variable between hopping mice. Also, organization of the seminiferous epithelium was less rigid in hopping mouse testes, and several anomalies were observed. These included: the occurrence of 2-4 cellular associations in about 20% (range 11.3-33.9%) of tubular cross-sections, deviations in cellular composition in certain cycle stages from that usually observed, and an increased incidence of degenerating cells, together with the presence of multinucleated "giant' cells, within the seminiferous epithelium.
Publisher: CSIRO Publishing
Date: 2005
DOI: 10.1071/RD05027
Abstract: In most mammals, post-testicular sperm maturation is completed in the caput and corpus epididymides, with storage occurring in the cauda epididymides. However, in the spinifex hopping mouse, Notomys alexis, epididymal sperm transit is rapid and some sperm storage occurs in the distal region of the vas deferens. The aim of the present study was to determine whether the rapid progression of sperm into the vas deferens in the hopping mouse results in late sperm maturation. To determine this, sperm nuclei from the epididymides and vasa deferentia of laboratory and hopping mice were compared for: (1) thiol content after staining with monobromobimane (mBBr) (2) chromatin resistance to acid denaturation following incubation with acetic alcohol and staining with acridine orange and (3) chromatin resistance to in vitro decondensation after incubation with 1% sodium dodecyl sulfate (SDS). It was found that, whereas laboratory mouse sperm completed chromatin condensation by the time they reached the cauda epididymidis, hopping mouse sperm nuclei from the vas deferens showed significantly less mBBr fluorescence and a greater proportion of sperm were resistant to decondensation with SDS than those in the cauda epididymidis. Therefore, the results of the present study indicate that, unlike in the laboratory mouse, hopping mouse chromatin condensation of spermatozoa continues in the vas deferens and this may be due, at least in part, to rapid epididymal transit.
Publisher: Bioscientifica
Date: 07-1972
Abstract: At the same time even laparoscopic adrenalectomy can become the source or the causing factor of a number of complications. In the following report we present the clinic case of diagnostic complications during postsurgical period of "rapid" development and signs of tuberculosis after laparoscopic adrenalectomy. The patient underwent ultrasonography and CT was found out: the tumor of right adrenal gland. Operational treatment: right laparoscopy adrenalectomy. Pathologistological conclusion: clear cell adenoma. On the fourth day there was a high temperature rise noted 38-39°C. On the 10th day the CT, where there were no signs of free liquid abscess formation. Relaparoscopic: small amount of serous-hemorrhagic liquid in small pelvis, hyperemated peritoneum, in both - left and right liver lobes tight knots of white color. After, the patient still had hyperthermia 38°C. Phthisiatrician consulted the patient and diagnosed abdominal tuberculosis. After six-month treatment the patient in satisfactory condition was discharged home. But in case of our patient's case such visual diagnostic methods, such as CT and ultrasonography of abdominal cavity appeared to be non-informative in lymph system diagnostics due to the number of reasons.The described clinical case and literature data prove the fact, that crucial in abdominal tuberculosis form management treatment is a diagnostic laparoscopy with tissue biopsy. Labors, as well as adrenalectomy are possible factors which decrease the immunity and can cause the activation of tuberculosis process. Diagnostic laparoscopy and intraoperative histological tissue study of abdominal cavity are the main points in prescribing diagnosis of abdominal tuberculosis form.
Publisher: Bioscientifica
Date: 02-2003
Abstract: The cauda epididymidis, with its relatively cool temperature (32-35 degrees C), is considered to be the main site of sperm storage in male mammals. However, in the adult male spinifex hopping mouse, Notomys alexis, similar numbers of spermatozoa are found in the vas deferens to those in the cauda epididymidis. The present study shows that, unlike in the laboratory mouse in which spermatozoa of the vas deferens are found mainly in the epididymal region of the duct, spermatozoa in the hopping mouse are localized mainly to the middle and urethral regions of the vas deferens which lies in the inguinal and lower abdominal region of the body cavity. After ligation of the vas deferens close to its connection with the epididymis, many spermatozoa in the vas deferens retain the potential for motility for up to 2 weeks, indicating that the viability of spermatozoa is not compromised by being restricted to core body temperature. This urethral region of the vas deferens, in which spermatozoa reside, has a highly ergent structural organization compared with that of common laboratory rodents in which there is an expanded lumen with a network of epithelial folds. Ultrastructural observations of the cells lining the duct indicate that there are not any marked differences in morphology compared with the cells lining the duct in common laboratory murids, but the infoldings of the vas deferens of the hopping mouse are highly vascular which might facilitate supply of oxygen and nutrients to the spermatozoa residing in the lumen.
Publisher: Cold Spring Harbor Laboratory
Date: 09-2023
Publisher: Bioscientifica
Date: 1990
Abstract: Hopping mice were examined to study two interrelated questions: (1) when groups of adults of both sexes are kept together in one cage in the laboratory is there evidence that the females copulate with only one male, and (2) is a copulatory plug formed in the female tract after ejaculation? The findings indicate that a female will sometimes lock with more than one male in the group during an oestrous period induced by administration of exogenous gonadotrophins, and that a small 'plug' of soft material forms post coitum in the more caudal parts of the female tract. In iduals of this species, therefore, do not appear to be strictly monogamous, at least in this artificial laboratory situation. Although a coagulum is formed, this is quite different from the typical hard copulatory plug that occurs in common laboratory murids it may possibly reduce sperm backflow from the lower region of the female reproductive tract.
Publisher: Wiley
Date: 2001
DOI: 10.1046/J.1469-7580.2001.19810057.X
Abstract: The sperm head structural organisation of the koala and hairy-nosed wombat, and the effects of varying concentrations of the ionic detergent, Triton X-100, on its component parts, were determined by electron microscopy. Although alike in form between the 2 species, the sperm nucleus of the former, but not the latter, had nuclear vacuoles and appeared to be more easily dispersed by the Triton X-100. The structure of the acrosome of the spermatozoon was similar between the 2 species and, in both, previously undescribed thin posterior and lateral segments were found to be present. It is suggested that this thin segment may facilitate sperm-zona and/or sperm-oolemma binding and fusion.
Publisher: Wiley
Date: 09-1994
Abstract: In marsupials implantation occurs about two-thirds the way through the short gestation before which time the embryo is surrounded by the permeable shell membrane which prevents physical contact between the trophoblast and uterine epithelium. Although the trophoblast has been shown to be invasive to varying degrees in several species of marsupials, the ultrastructure of the embryonic-uterine cell interactions at the time of implantation has not been described in this group. Thick plastic sections and transmission electron microscopy were employed to investigate the cellular interactions at implantation in the fat-tailed dunnart (Sminthopsis crassicaudata), a dasyurid Australian marsupial. Our results show that epithelial penetration begins when the embryo is at the late presomite/early somite stage. In the trilaminar region of the yolk sac (TYS), trophoblast cells adjacent to the embryo form desmosomes with uterine epithelial cells and also appear to fuse with them to form hybrid cells, the cytoplasm of which resembles that of trophoblast. Later in the TYS, as the placenta develops, trophoblast microvilli and larger cell processes invaginate, and interdigitate with, the highly folded maternal epithelium but do not invade it. At this time in the bilaminar, or avascular, yolk sac (BYS), multinucleate trophoblast giant cells (TGCs) from an annular region adjacent to the sinus terminalis intrude between, and possibly fuse with, the maternal epithelium. The invading TGCs spread laterally above the residual basal lamina before migrating into the stroma. In this species of marsupial at least, the cell interactions at the time of implantation are similar to those seen in some eutherian species despite the fact that the fetal chorion is of yolk sac rather than allantoic origin.
Publisher: Elsevier BV
Date: 06-2000
DOI: 10.1016/S0031-9384(99)00264-4
Abstract: To determine the effects of photoperiod and ovarian steroids on fat stores in the marsupial S. crassicaudata, animals were ovariectomised (OVX) or sham operated, and maintained under either short-day (SD) or long-day (LD) photoperiods for 104 days. Photoperiod had no effect on body weight in the sham animals. In the LD OVX animals, body weight fell and remained below baseline for about 45 days, whereafter it returned to baseline. In contrast, body weight of SD OVX animals increased over the first 45 days then returned to baseline. Tail width (a reflection of body fat stores) increased in both sham and OVX animals exposed to SD. When exposed to LD, tail width increased only in the OVX animals. There was no effect of either photoperiod or OVX on total cumulative energy intake. Leptin mRNA expression was increased in the LD OVX animals compared to the shams. Photoperiod had no effect on UCP2 mRNA expression in any tissue however, OVX decreased UCP2 mRNA expression in muscle. These data indicate that in S. crassicaudata: (a) fat mass increases in response to both SD photoperiod and OVX and they have additive effects (b) the effects of photoperiod on fat mass are mediated by both gonadal steroid dependent and independent mechanisms (c) alterations in UCP2 mRNA expression may mediate the effect of OVX, but not photoperiod and (d) UCP2 mRNA is differentially regulated in muscle and fat.
Publisher: CSIRO Publishing
Date: 2014
DOI: 10.1071/RD13162
Abstract: Spermatozoa of the plains mouse (Pseudomys australis), like those of most Australian old endemic rodents, contain, in addition to an apical hook, two further processes that extend from the upper concave surface of the head, the ventral processes. This study shows that these processes contain thiol-rich cytoskeletal proteins, which presumably help to maintain their rigidity during sperm transport, together with the overlying cell membrane having abundant intramembranous proteins. To determine the possible functional significance of these processes, an in vitro study of spermatozoon–zona binding was undertaken. The findings suggest that initial sperm binding occurs by way of the cell membrane over the acrosome of the apical hook and that, subsequently, the lateral surfaces of the ventral processes also become tightly bound to the zona matrix. These ventral processes may therefore have evolved to increase sperm adhesion to the outer zona surface and/or to enhance stabilisation of the spermatozoon at the time of zona binding and initial penetration of the egg coat.
Publisher: Springer Science and Business Media LLC
Date: 05-1967
DOI: 10.1038/214826A0
Abstract: Snakebite is considered as a significant public health problem contributing considerably to morbidity and mortality. A neurotoxic snake bite can present from mild ptosis to complete paralysis with external and internal ophthalmoplegia. Three patients presented in emergency intubated outside with deeply comatose, fixed dilated pupil, and absent doll's eye reflex mimicking as brain dead.
Publisher: Wiley
Date: 08-1997
DOI: 10.1002/(SICI)1097-010X(19970801)278:5<322::AID-JEZ6>3.0.CO;2-R
Publisher: Bioscientifica
Date: 02-1972
Publisher: Bioscientifica
Date: 11-1997
Abstract: The structural organization of the chromatin of cauda epididymal spermatozoa of the red veld rat Aethomys chrysophilus type B was investigated by fluorescence microscopy after staining with DNA specific dyes and by transmission electron microscopy after incubation with Triton X100, dithiothreitol, and SDS. Staining with DNA dyes showed variation in intensity of fluorescence of the sperm chromatin, with an anterior spherical region staining far more intensely than the surrounding chromatin. Transmission electron microscopy of these spermatozoa indicated that this region was composed of cords and fibres. This chromatin region dispersed more readily than the surrounding chromatin when spermatozoa were incubated with the detergents, and it is suggested that, unlike the rest of the sperm chromatin, it may be a histone-rich region, with protamine(s) being either scarce or absent.
Publisher: Wiley
Date: 06-1987
Abstract: The sperm head of the plains mouse, Pseudomys australis, has three curved hooks projecting from its anterior margin. The two ventral hooks have previously been shown to consist largely of an extension of the subacrosomal material. To characterize further the structure and composition of the ventral hooks, we have examined their formation during spermiogenesis using transmission electron microscopy, silver staining, and actin localization with NBD-phallacidin. The ventral hooks develop as an extension of the perinuclear space and postacrosomal dense lamina on the anteroventral margin of the sperm head. Bundles of 6-nm-thick filaments appear in the core of each hook these are probably actin filaments based on staining of the hooks with NBD-phallacidin. Just prior to spermiation, electron-dense material condenses in the core of the ventral hooks and concurrently in the perinuclear space in the remainder of the sperm head. The two ventral hooks thus appear to consist of a core of perinuclear material and actin filaments, which is enclosed by a continuation of the postacrosomal dense lamina.
Publisher: Bioscientifica
Date: 10-1970
Publisher: Wiley
Date: 26-07-2005
Publisher: Wiley
Date: 14-05-2014
DOI: 10.1111/AZO.12036
Publisher: Oxford University Press (OUP)
Date: 20-08-1980
DOI: 10.2307/1379849
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/RD08187
Abstract: The Australian murine rodent, the plains mouse (Pseudomys australis), possesses a highly complex sperm head, in which there are, in addition to an apical hook, two ventral processes that extend from its upper concave surface. The present study set out to determine the temporal deposition and distribution of the proteins within these structures during late spermiogenesis by light and electron microscopy using various antibodies to bull and laboratory rat sperm-head cytoskeletal proteins. The findings show that there are two phases of protein deposition. In the first phase, perinuclear theca proteins are deposited at the base of the ventral processes around the acrosomal extensions of the developing spermatids. In the second phase, as the ventral processes expand, actin and then perforatorial proteins are laid down during which time the processes become progressively more bilaterally flattened. These various proteins are moulded together to give rise to the two very large cytoskeletal structures that extend from the upper concave surface of the sperm head. They may be involved in binding the spermatozoon to the outer surface of the zona pellucida and/or in aiding the spermatozoon in zona penetration at the time of fertilisation.
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/RD9960673
Abstract: The effects of long-term cooling and freezing on sperm motility are described for six marsupial species: the fat-tailed dunnart, koala, brushtail possum, long-footed potoroo, northern brown bandicoot and ring-tailed possum. The effects of up to eight days of cooling at 4 degrees C on the motility of dunnart spermatozoa and the effect of cryopreservation on spermatozoa of the other species were determined. The cryoprotectant used was a Tris-citrate-fructose-egg yolk-glycerol diluent. The percentage and rating of sperm motility, and sperm structure, as determined by light microscopy, were investigated. Sperm motility in the fat-tailed dunnart was retained for up to six days when cooled to 4 degrees C, suggesting that sperm from this species have some degree of tolerance to cold shock. After this time, however, the percentage of motile spermatozoa and their motility rating declined. In all species except the fat-tailed dunnart, reinitiation of motility following cryopreservation occurred across a range of glycerol concentrations (4-17%). Cryoprotectant containing 6% and/or 8% glycerol resulted in little change of motility rating or of the percentage of live sperm after thawing, although there was some decline in the percentage of motile sperm. The unusual structural and motility characteristics of dunnart spermatozoa may account for the lack of success of sperm cryopreservation in this species.
Publisher: Medknow
Date: 07-06-2010
DOI: 10.1038/AJA.2010.41
Publisher: Bioscientifica
Date: 03-1985
Abstract: Morphological studies of the vagina and cervix from females of several species of Pseudomys (pseudo-mice) and Notomys (hopping-mice) have shown marked interspecific differences. In females of all four species of Pseudomys and in N. cervinus there was a relatively thin walled, dorsoventrally flattened, vagina with a large lumen, longitudinal epithelial folds, and conspicuous fornices. By contrast, in females of N. alexis and N. mitchelli the vagina had a much smaller lumen, few or no folds, minute fornices, but a well developed muscle coat. The cervix of the Pseudomys females was a conspicuous fibrous structure, rich in collagen, with two canals throughout its length. In N. cervinus females it was smaller and the two canals, although separated by a median septum for much of their lengths, joined just before the external os. In N. alexis and N. mitchelli females the cervix was much less extensive, its boundaries could not be discerned externally, and, histologically, it was more cellular and less fibrous. This variation in morphology of the female reproductive tract appears to complement that of the excurrent ducts, accessory sex glands and external genitalia of males of these species of Australian murid rodents.
Publisher: Cambridge University Press (CUP)
Date: 31-10-2002
DOI: 10.1017/S0967199402004021
Abstract: This comparative study of the cDNA sequence of the zona pellucida C (ZPC) glycoprotein in murid rodents focuses on the nucleotide and amino acid sequence of the putative sperm-combining site. We ask the question: Has ergence evolved in the nucleotide sequence of ZPC in the murid rodents of Australia? Using RT-PCR and (RACE) PCR, the complete cDNA coding region of ZPC in the Australian hydromyine rodents Notomys alexis and Pseudomys australis , and a partial cDNA sequence from a third hydromyine rodent, Hydromys chrysogaster , has been determined. Comparison between the cDNA sequences of the hydromyine rodents reveals that the level of amino acid sequence identity between N. alexis and P. australis is 96%, whereas that between the two species of hydromyine rodents and M. musculus and R. norvegicus is 88% and 87% respectively. Despite being reproductively isolated from each other, the three species of hydromyine rodents have a 100% level of amino acid sequence identity at the putative sperm-combining site. This finding does not support the view that this site is under positive selective pressure. The sequence data obtained in this study may have important conservation implications for the dissemination of immunocontraception directed against M. musculus using ZPC antibodies.
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/RD06045
Abstract: In Australia, there are around 60 species of murid rodents that occur in the subfamily Hydromyinae, most of which produce highly complex, monomorphic, spermatozoa in which the head has an apical hook together with two ventral processes containing filamentous actin and a long tail of species-specific length. One of the few exceptions to this is the spinifex hopping mouse, Notomys alexis, whose spermatozoa have previously been shown to have pleiomorphic heads. In this study, the structural organisation of the sperm head has been investigated in more detail and the variability in length of the midpiece and total length of the sperm tail has been determined for this species. The findings confirm that pleiomorphic sperm heads are invariably present in these animals and that this variability is associated with that of the nucleus, although nuclear vacuoles were not evident. The total length of the sperm tail, as well as that of the midpiece, was also highly variable both within, as well as between, in idual animals. The reason(s) for this high degree of variability in sperm morphology is not known but it may relate to a relaxation of the genetic control of sperm form owing to depressed levels of inter-male sperm competition.
Publisher: Elsevier BV
Date: 04-1996
Publisher: No publisher found
Date: 1989
DOI: 10.1071/ZO9890207
Publisher: Wiley
Date: 04-1989
Publisher: Wiley
Date: 11-01-2012
DOI: 10.1002/JMOR.20011
Publisher: Wiley
Date: 31-05-2018
DOI: 10.1111/JZO.12573
Publisher: Oxford University Press (OUP)
Date: 21-05-1981
DOI: 10.2307/1380714
Publisher: CSIRO Publishing
Date: 1977
DOI: 10.1071/ZO9770401
Abstract: The histological structure of the ovary of the lactating hopping-mouse is described. Two sets of corpora lutea are usually present, one of which appears to degenerate fairly rapidly during lactation and is thus considered to be the corpora lutea of pregnancy. Spontaneous ovulation usually occurs after parturition thus corpora lutea of lactation are formed which appear to remain healthy-looking throughout most of lactation. Oocytes were flushed from Fallopian tubes immediately after parturition, but then not again until at least day 10 of lactation. Vesicular follicles were not present after post-partum ovulation, but had usually developed by day 5. In females suckling three or more young, however, maximum follicular size did appear to be somewhat inhibited, compared to that in females suckling one young, from days 5 to 11 of lactation by day 15 larger vesicular follicles had developed and recently formed corpora lutea were present in one in idual.
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/AM15028
Abstract: The Australian water rat (Hydromys chrysogaster), unlike most murine rodents, has a carnivorous diet. In the present study the morphology of its gastrointestinal tract is described and compared with that of other muroid rodents with more typical diets. It was found that the stomach of the water rat is relatively small and has a greater proportion of glandular epithelium than that of other species so far investigated. Comparisons of relative intestinal lengths showed that in the Australian water rat there is a comparatively long small intestine that constitutes ~90% of the total intestinal length, a short large intestine, and a small caecum. This ergent morphology of the gastrointestinal tract of the Australian water rat probably relates to the animal’s protein-rich diet, with the differences from those of other hydromyine rodents indicating considerable plasticity in the evolution of the gastrointestinal tract in this group of mammals. It suggests that, whilst the morphological adaptations of the water rat’s gastrointestinal tract probably evolved before the colonisation of Australia, its highly derived morphology has enabled this species to exploit the Australian environment as an aquatic carnivore.
Publisher: Bioscientifica
Date: 03-1981
Abstract: Spermatozoa of plains mice were studied by transmission and scanning electron microscopy. The occurrence of a distinct dorsal hook and 2 ventral hooks joined at the base was confirmed. Acrosomal material covered the dorsal hook and appeared to constitute most of the 2 ventral hooks which contained nuclear material only at the base. Incubation in sodium dodecyl sulphate resulted in loss of all the material presumed to be acrosomal.
Publisher: Wiley
Date: 26-08-2004
Publisher: Wiley
Date: 04-01-2008
Publisher: Elsevier BV
Date: 07-1994
Abstract: The marsupials represent a separate evolutionary lineage from eutherians from which they erged over 100 million years ago. In order to explore the origin and mode of centrosome inheritance amongst this group of mammals, this study investigates the microtubule organization during fertilization, parthenogenesis, and polyspermy in the didelphid, Monodelphis domestica. Microtubules and DNA were visualized in maturing ovarian oocytes, parthenogenetically activated oocytes, monospermic and polyspermic zygotes, and early embryos. Ovarian oocytes had a central region of yolky cytoplasm that, after fertilization, became polarized much of the yolk was then extruded into the perivitelline space as an enucleated cytoplasmic mass. Immunofluorescence microscopy, using a monoclonal antibody to beta-tubulin, demonstrated microtubules in the meiotic spindle in unfertilized oocytes, but cytasters were not detected. After fertilization, a cluster of microtubules forming into a sperm aster was evident around the male pronucleus. The sperm aster remained largely restricted to the nonyolky region of the egg cytoplasm, resulting in a cytoplasmic heterogeneity between a microtubule-rich region and one in which microtubules were largely absent. Once the two pronuclei came close together, abundant microtubules were found surrounding both pronuclei. In the early embryo, microtubules were found in the outer cortical region of the blastomeres and, in addition, there was an extensive and elaborate network of microtubules throughout the yolk mass. Disruption of the meiotic spindle microtubules with nocodazole or cold treatment did not result in chromosome dispersion in the cortex and recovery from drug or cold depolymerization demonstrated that microtubules might not be as dynamic as those in eutherian mammals. Taxol stabilization resulted in an increase in cortical microtubules. In this marsupial species, therefore, the centrosome appears to be of paternal origin, and the radiating microtubules that form may well be involved both in bringing the pronuclei together and in the cytoplasmic polarization that results in extrusion of the yolk mass.
Publisher: Elsevier BV
Date: 12-1976
Publisher: Bioscientifica
Date: 1994
Abstract: A light microscope study of the choriovitelline (yolk sac) placenta of the dasyurid marsupial, Sminthopsis crassicaudata, and some comparative observations on that of the didelphid, Monodelphis domestica, were performed. In the former species, the placenta was composed of an invasive bilaminar, avascular, yolk sac and a non-invasive trilaminar, vascular yolk sac. The bilaminar yolk sac placenta had trophoblast giant cells that eroded the maternal epithelium, but there was no evidence of invasion of maternal capillaries thus, an endotheliochorial placenta was present. In the trilaminar yolk sac placenta, the convoluted chorion followed the contours of the highly folded endometrial epithelium but did not erode it and, therefore, an epitheliochorial placenta was formed. In late pregnancy, the choriovitelline placenta of Monodelphis domestica also had two regions, but the fetal trophoblast did not invade the uterine epithelium in either region. Rather, there were discontinuous areas of adhesion between trophoblast giant cells and uterine epithelium in the trilaminar yolk sac placenta and some extensive areas of adhesion in the attenuated bilaminar yolk sac placenta. The yolk sac placenta in M. domestica, unlike that of S. crassicaudata, therefore appears to be epitheliochorial in the vascular and non-vascular regions.
Publisher: SAGE Publications
Date: 08-2013
Abstract: The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level of renal dysfunction in which crystals consistent with calcium oxalate have been observed in the kidneys. This study aimed to describe the pathological features of the renal disease in this population, confirm the composition of renal crystals as calcium oxalate, and determine whether any age or sex predispositions exist for this disease. A total of 51 koalas (28 wild rescues, 23 captive) were examined at necropsy, of which 28 (55%) were found to have gross and/or histological evidence of oxalate nephrosis. Histopathological features included intratubular and interstitial inflammation, tubule dilation, glomerular atrophy, tubule loss, and cortical fibrosis. Calcium oxalate crystals were demonstrated using a combination of polarization microscopy, alizarin red S staining, infrared spectroscopy, and energy-dispersive X-ray analysis with scanning electron microscopy. Uric acid and phosphate deposits were also shown to be present but were associated with minimal histopathological changes. No significant differences were found between the numbers of affected captive and wild rescued koalas also, there were no sex or age predispositions identified, but it was found that oxalate nephrosis may affect koalas years of age. The findings of this study suggest that oxalate nephrosis is a leading disease in this koala population. Possible causes of this disease are currently under investigation.
Publisher: Wiley
Date: 25-03-2011
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/RD9960797
Abstract: Pre- and peri-implantation embryos of the dasyurid marsupial Sminthopsis crassicaudata were examined for morphological differentiation of the trophectoderm. The cells of unilaminar blastocysts were all squamous and stained intensely with toluidine blue. In bilaminar blastocysts and embryos at the early embryonic-disc stage, the trophectoderm was similar in appearance to, but stained more lightly than, the underlying endoderm. Trophoblast differentiation did not appear to occur until the mesoderm had begun to migrate between the trophoblast and endoderm beyond the embryonic disc. At this stage, trophoblasts had three distinct morphologies: (1) vacuolated, tall and columnar cells in the trilaminar region (2) large cuboidal cells in the adjacent bilaminar region and (3) squamous cells in the abembryonic pole of the bilaminar region. These variations in cell structure correlate with differences in subsequent functional activity in these three regions of the yolk sac placenta.
Publisher: Elsevier BV
Date: 02-1974
DOI: 10.1016/0010-7824(74)90029-8
Abstract: African American/Black men who have sex with men (MSM) in the U.S. experience health and social disparities at greater rates than MSM of other races/ethnicities, including HIV infection and substance use. This mixed methods paper presents: 1) a quantitative examination of health and social disparities among a s le of substance-using African American/Black MSM (N=108), compared to Caucasian/White MSM (N=250), and 2) in-depth qualitative data from a subs le of African American/Black MSM (N=21) in order to contextualize the quantitative data. Findings indicate that compared to Caucasian/White MSM, African American/Black MSM experienced a wide range of health and social disparities including: substance use and dependence buying, trading or selling sex educational attainment employment homelessness identifying as gay HIV status arrest history social support and satisfaction with one's living situation. Qualitative data suggests that structural interventions that address homophobia and the social environment would be likely to mitigate many of the health and social disparities experienced by African American/Black MSM.
Publisher: Walter de Gruyter GmbH
Date: 1985
Publisher: Springer Science and Business Media LLC
Date: 23-08-2008
DOI: 10.1007/S00441-008-0668-7
Abstract: Male germ cells of the greater bandicoot rat, Bandicota indica, have recently been categorized into 12 spermiogenic steps based upon the morphological appearance of the acrosome and nucleus and the cell shape. In the present study, we have found that, in the Golgi and cap phases, round spermatid nuclei contain 10-nm to 30-nm chromatin fibers, and that the acrosomal granule forms a huge cap over the anterior pole of nucleus. In the acrosomal phase, many chromatin fibers are approximately 50 nm thick these then thickened to 70-nm fibers and eventually became 90-nm chromatin cords that are tightly packed together into highly condensed chromatin, except where nuclear vacuoles occur. Immunocytochemistry and immunogold localization with anti-histones, anti-transition protein2, and anti-protamine antibodies suggest that histones remain throughout spermiogenesis, that transition proteins are present from step 7 spermatids and remain until the end of spermiogenesis, and that protamines appear at step 8. Spermatozoa from the cauda epididymidis have been analyzed by acid urea Triton X-100 polyacrylamide gel electrophoresis for basic nuclear proteins. The histones, H2A, H3, H2B, and H4, transitional protein2, and protamine are all present in sperm extracts. These findings suggest that, in these sperm of unusual morphology, both transition proteins and some histones are retained, a finding possibly related to the unusual nuclear form of sperm in this species.
Publisher: Bioscientifica
Date: 02-2001
Abstract: The plains rat, Pseudomys australis, and the spinifex hopping mouse, Notomys alexis, show marked differences in the size of their testes and in the number of spermatozoa within the epididymides. In the present study, the dynamics of sperm production and the duration of sperm transit along the male excurrent ducts were compared between these two species. The durations of the cycle of the seminiferous epithelium, spermatogenesis and sperm transit were determined by tracking cells using autoradiography after [(3)H]thymidine incorporation. Daily sperm production was determined from counts of testicular spermatids after homogenization and further estimates of sperm transit were obtained by iding sperm reserves within the various regions of the extratesticular ducts by the daily sperm production of the attached testis. In the plains rat, the mean duration of the cycle of the seminiferous epithelium was 11.2 days, the duration of spermatogenesis was 45 days, daily sperm production was 2.6 x 10(7) spermatozoa per gram of testis and epididymal transit of spermatozoa took approximately 9 days (caput 0.8 days corpus 1.5 days cauda 6.5 days). In contrast, in the hopping mouse, the mean duration of the cycle of the seminiferous epithelium was 14 days, the duration of spermatogenesis was 56 days and daily sperm production per gram of testis was 1.0 x 10(7). Epididymal transit of spermatozoa was completed in about 4 days (caput + corpus 1 day cauda 3 days) however, spermatozoa may be stored for an additional 1.5-2.0 days in the vas deferens. These results indicate that, in addition to small testes, the hopping mouse shows a low efficiency of sperm production, a relatively long duration of spermatogenesis and rapid passage of spermatozoa through the epididymis, all of which contribute to low epididymal sperm counts. These data are considered in relation to interspecific differences in sperm competition.
Publisher: Wildlife Disease Association
Date: 04-2013
DOI: 10.7589/2012-10-256
Abstract: We examined the clinical and cellular effects of sarcoptic mange on southern hairy-nosed wombats (SHNW, Lasiorhinus latifrons) and the effectiveness of a single dose of ivermectin as a treatment for captive and wild animals. Wambats were caught at three sites in South Australia between April and August 2005 and blood and skin s les were collected. Hematology, biochemistry, and protein electrophoresis reference intervals were determined for healthy and diseased SHNW. Diseased SHNW had significantly higher white blood cell counts, neutrophils, lymphocytes, and total protein but lower red blood cell counts, hemoglobin, hematocrit, and creatinine. Microscopic investigation indicated substantial hyperplasia, hyperkeratosis, and fluid infiltration into the dermis and epidermis of diseased animals. Conclusions on the efficacy of a single dose of ivermectin were limited by low s le size (n=5, two captive and three wild SHNW) and are preliminary. However, ivermectin effectively treated mild, but not severe, mange in wild SHNW and severe mange in captive animals. This study has implications for the conservation and management of SHNW and the broader Vombatidae family.
Publisher: Elsevier BV
Date: 10-1973
Publisher: The Royal Society
Date: 24-04-1984
Abstract: Mammals generally ejaculate many more spermatozoa than seem to be needed for fertilization. This apparent profligacy has not been explained, but observations made in marsupials may shed light on it. The Virginia opossum, Didelphis virginiana , inseminates only about three million spermatozoa, a very low number. As a corollary, relatively few ( ca . 13 x 10 6 ) are stored in each cauda epididymidis. However, some 5% of the spermatozoa that the opossum ejaculates populate the oviduct about 12 h later when ovulation can be anticipated - a success rate in the female orders of magnitude greater than in eutherian mammals. I t is not certain what determines the unusually efficient transport to and the high survival rate of spermatozoa in the oviduct of Didelphis , but two unusual features suggest themselves as possible contributors. Didelphis (and all other American marsupial) spermatozoa undergo a head-to-head pairing in the epididymis by the acrosomal face this serves to isolate the acrosome of ejaculated spermatozoa from the female milieu until the pairs separate in the oviduct. Secondly, spermatozoa are housed in special crypts in the isthmus of the oviduct. Australian marsupials, which usually lack such features, store spermatozoa in the epididymis in numbers more close to those in comparably sized eutheriam mammals. Exceptions which store very low sperm numbers there can be seen in one Australian Family, the Dasyuridae. The spermatozoa of dasyurids are not paired, but the species examined possess distinctive sperm storage crypts in the oviducal isthmus similar to those in the opossum. The present findings suggest that where mechanisms exist that could protect the acrosome and, or, the whole spermatozoon in the female tract, a much lower level of sperm production can be maintained without compromising fertility. While the number ejaculated typically by any one species is probably determined ultimately by several interacting factors, it therefore seems likely that a most important one in this respect relates to conditions spermatozoa face in the female tract.
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/RD9961097
Abstract: The Zn(II)-specific fluorophore Zinquin was used to determine the regional distribution of free or loosely-bound Zn(II) in mouse spermatozoa. Spermatozoa from the testes exhibited bright fluorescence over the entire head those from the caput epididymides generally fluoresced more brightly in the post-acrosomal region and spermatozoa from the caudae epididymides fluoresced less brightly, with foci of fluorescence over the sperm head which were lost after extraction with Triton X-100 and hence appeared to be membrane-associated. Treatment of cauda sperm with sodium dodecyl sulfate resulted in a bright uniform Zinquin fluorescence in the heads, similar to that observed in caput sperm, indicating that the two types of sperm have similar amounts of head Zn(II) but that the availability of Zn(II) for binding Zinquin is different. By contrast, the intensity of tail fluorescence was similar in spermatozoa from different regions of the male reproductive tract and was largely unaffected by Triton X-100 extraction, consistent with an intracellular location. Similar differences were observed between caput sperm and cauda sperm in the rat. It is concluded that visualization and measurement of free or loosely-bound Zn(II) in subcellular compartments of spermatozoa should facilitate investigation of the role of this metal in the development and function of spermatozoa and abnormalities that might accompany infertility and Zn(II) deficiency.
Publisher: CSIRO Publishing
Date: 1991
DOI: 10.1071/RD9910303
Abstract: The transillumination-assisted isolation of segments of seminiferous tubules in defined stages of the wave of the seminiferous epithelium was investigated in Pseudomys australis and Notomys alexis. In P. australis, three different transillumination patterns (pale, spotty and dark) of the seminiferous tubules could be isolated. They corresponded to histological stages 1-2, 3-5 and 6-8 of the wave of the seminiferous epithelium. The dark pattern made up about 40% of the wave, the pale pattern about 31%, and the spotty pattern about 24%. In N. alexis, no such isolation of segments with particular cell associations was possible. In a comparison of P. australis with the laboratory rat, the dark, pale and spotty transillumination patterns of seminiferous tubule segments corresponded to the same cell associations in both species, but the length of the spotty segments in the laboratory rat made it possible to sub ide the spotty region into pale spotty and dark spotty areas and thus to isolate four different transillumination patterns. Further separation into other subgroups to isolate additional types of segments could not be performed repeatedly in any of the studied species because of the gradual change of one subgroup of transillumination pattern into another and the short length of some of the subgroups.
Publisher: Wiley
Date: 07-1989
Abstract: The sperm head of many Australian hydromyine rodents has three curved hooks projecting from its anterior margin the structure of the hooks has been characterized, but their function is unknown. In this study, we have investigated whether the hooks might have evolved to assist sperm penetration through more formidable egg vestments, particularly the zona pellucida. Cumulus-oocyte complexes were obtained from two species that possess a three-hooked sperm head (Pseudomys australis and P. nanus) and one species that does not (Notomys alexis) and examined by light and electron microscopy. After fixation in the presence of ruthenium red, the zona pellucida was found to consist of a fibrillar meshwork, but there were no interspecific structural differences. A corona radiata was absent, and the cumulus extracellular matrix was composed of filaments and electron-dense granules in each species. Measurements of the zona thickness in freshly ovulated, unfixed oocytes revealed that it was thinnest (7.8 microns) in P. australis, which has a three-hooked sperm head, and thickest (11.4 microns) in N. alexis, the species in which the ventral hooks are absent. Hence, no correlation was found between the thickness of the zona pellucida or the structure of the cumulus-oocyte complex, and the presence of three hooks on the sperm head. We conclude, therefore, that it is unlikely that the evolution of the three-hooked sperm head is an adaptation for penetration of increased barriers around the oocyte.
Publisher: Elsevier BV
Date: 02-2005
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/RD18278
Abstract: The high ersity of native Philippine murid rodents includes an old endemic group, the chrotomyines, which are the sister group of the Australasian hydromyines. Herein we detail their interspecific ersity of relative testes mass (RTM) and sperm morphology. We find that in chrotomyines, as in the Australasian hydromyines, testes mass relative to body mass differs by an order of magnitude across the species and ranges from a large RTM in Soricomys and Chrotomys species to a small RTM in Apomys. Sperm morphology is associated with these findings, with in iduals in species of Soricomys and Chrotomys producing relatively larger spermatozoa with a prominent apical hook and long tail, whereas, by contrast, the Apomys species have a sperm head that either has a very short or no apical hook and a shorter tail. These findings indicate coevolution of RTM with sperm morphological traits across the species, with the marked interspecific differences in RTM suggesting differences in the intensity of intermale sperm competition and hence breeding system. Thus, we hypothesise that species of Soricomys and Chrotomys that produce more streamlined spermatozoa with longer tails have a polyandrous or promiscuous mating system, whereas the Apomys species, which produce smaller and less streamlined spermatozoa, may exhibit monogamy.
Publisher: Springer Science and Business Media LLC
Date: 22-03-1996
Abstract: In the dasyurid marsupial, Sminthopsis crassicaudata, as the oocytes/embryos travel down the female reproductive tract two extracellular coats, the mucoid and shell membrane, come to surround them. Embryos recovered from the oviduct have a mucoid coat but no shell membrane which is only found surrounding uterine embryos. Initially, the shell membrane has a compact granular consistency but it later thins and becomes fibrous in texture with fibres oriented mainly in the plane of the membrane. Immunogold labelling with polyclonal antibodies raised against the extracellular coats was employed to determine the location and ultrastructural appearance of the secretory granules which contain mucoid and shell membrane precursors. Secretory granules in the luminal epithelium of the ulla of the oviduct are of irregular electron density, while those in the isthmus are electron-dense and homogeneous. Both types give rise to the mucoid coat. Secretory granules in the epithelia of the utero-tubal junction and some endometrial glands are electron-lucent and contain some flocculent material which, after exocytosis, gives rise to the shell membrane.
Publisher: CSIRO Publishing
Date: 25-02-2022
DOI: 10.1071/RD21255
Abstract: Context Sperm morphology varies greatly across mammalian species and this variability is especially evident in murid rodents with both sperm head shape and tail length being sexually selected traits. The Palawan spiny rat, Maxomys panglima has a longer sperm tail than that currently recorded for any other mammalian species. Aims The aim of the current study was to determine the sperm morphology of an in idual Palawan spiny rat, M. panglima. Methods Light and transmission electron microscopy were carried out. Key results We found that the sperm tail of M. panglima has an average length of 380 μm with the midpiece being approximately 185 μm in length with comparatively small mitochondria but very large coarse fibres. Furthermore, the sperm head has a less acutely flexed apical hook than that of most other murid rodents including those of several other Maxomys species. Conclusions The Palawan spiny rat has a highly ergent sperm morphology with an extremely long tail. It may turn out to be an important species for testing various hypotheses of sperm form and function in mammals. Implications These findings suggest markedly different selective pressures may have resulted in this unique sperm morphology, the functional significance of which remains to be determined.
Publisher: Wiley
Date: 19-02-2009
DOI: 10.2164/JANDROL.108.006569
Abstract: The cytokine transforming growth factor beta1 (TGFB1) is implicated in male sexual function. Previous behavioral studies show that Tgfb1 null mutant mice mount and display limited intromission behavior with receptive females but are unable to complete successful copulation. The studies presented here explore the physiologic basis for sexual dysfunction in Tgfb1 null mutant males. Scanning electron microscopy revealed that the surface of the penis in Tgfb1 null mutant males was abnormally coated in superficial keratinized epithelial cells. There was a significant reduction in protrusion of penile spines through the superficial tissue in Tgfb1 null mutant mice in some mice, the spines were almost completely embedded. Histologic analysis revealed reduced skin thickness in the penis of Tgfb1 null mutant males. Nerve fibers, endothelial cells, smooth muscle actin, macrophages, and neuronal and inducible nitric oxide synthase were present in similar abundance and location in Tgfb1 null mutant mice compared with wild-type controls however, an increase in collagen I deposition was detected. Behavioral studies revealed that Tgfb1 null mutant males undergo spontaneous noncontact erections, albeit at a reduced rate compared with control mice, and engage in less frequent genital grooming activity. These studies suggest that Tgfb1 null mutation may adversely influence copulatory behavior through effects on both altered structural integrity of the penile skin and impaired tissue compliance leading to erectile dysfunction.
Publisher: Bioscientifica
Date: 12-1970
Abstract: The aim of this work was to assess the microbiota (fungi and bacteria) and particulate matter in optical shops, contributing to a specific protocol to ensure a proper assessment. Air s les were collected through an impaction method. Surface and equipment swab s les were also collected side-by-side. Measurements of particulate matter were performed using portable direct-reading equipment. A walkthrough survey and checklist was also applied in each shop. Regarding air s ling, eight of the 13 shops analysed were above the legal requirement and 10 from the 26 surfaces s les were overloaded. In three out of the 13 shops fungal contamination in the analysed equipment was not detected. The bacteria air load was above the threshold in one of the 13 analysed shops. However, bacterial counts were detected in all s led equipment. Fungi and bacteria air load suggested to be influencing all of the other surface and equipment s les. These results reinforce the need to improve air quality, not only to comply with the legal requirements, but also to ensure proper hygienic conditions. Public health intervention is needed to assure the quality and safety of the rooms and equipment in optical shops that perform health interventions in patients.
Publisher: Informa UK Limited
Date: 1981
DOI: 10.3109/01485018108987534
Abstract: The plains mouse has large seminal vesicles, coagulating glands, and dorsal and ventral prostates, whereas in the hopping mouse the only large accessory sex gland is the ventral prostate. Fructose concentration was found to be high in the coagulating glands and dorsal prostate of the plains mouse, but low in all other glands of both species low concentrations of glucose were found in all glands. Citric acid concentration was high in the dorsal prostate of the plains mouse and ventral prostate of the hopping mouse. Acid and alkaline phosphatase activities were low in all glands of both species. In castrated hopping mice, enlargement of vestigial glands could not be induced with high doses of exogenous testosterone, although there was increased secretory activity of the seminal vesicle epithelial cells.
Publisher: Wiley
Date: 2005
DOI: 10.1002/JMOR.10357
Abstract: In the rodent superfamily Muroidea, a model for the evolution of sperm form has been proposed in which it is suggested that a hook-shaped sperm head and long tail evolved from a more simple, nonhooked head and short tail in several different subfamilies. To test this model the shape of the sperm head, with particular emphasis on its apical region, and length of sperm tail were matched to a recent phylogeny based on the nucleotide sequence of several protein-coding nuclear genes from 3 families and 10 subfamilies of muroid rodents. Data from the two other myomorph superfamilies, the Dipodoidea and kangaroo rats in the Geomyoidea, were used for an outgroup comparison. In most species in all 10 muroid subfamilies, apart from in the Murinae, the sperm head has a long rostral hook largely composed of acrosomal material, although its length and cross-sectional shape vary across the various subfamilies. Nevertheless, in a few species of various lineages a very different sperm morphology occurs in which an apical hook is lacking. In the outgroups the three species of dipodid rodents have a sperm head that lacks a hook, whereas in the heteromyids an acrosome-containing apical hook is present. It is concluded that, as the hook-shaped sperm head and long sperm tail occur across the muroid subfamilies, as well as in the heteromyid rodents, it is likely to be the ancestral condition within each of the subfamilies with the various forms of nonhooked sperm heads, that are sometimes associated with short tails, being highly derived states. These findings thus argue against a repeated evolution in various muroid lineages of a complex, hook-shaped sperm head and long sperm tail from a more simple, nonhooked sperm head and short tail. An alternative proposal for the evolution of sperm form within the Muroidea is presented in the light of these data.
Publisher: Wiley
Date: 19-04-2007
Publisher: Cambridge University Press (CUP)
Date: 08-1994
DOI: 10.1017/S0967199400001994
Abstract: The 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.
Publisher: Wiley
Date: 05-1990
Publisher: Walter de Gruyter GmbH
Date: 1985
Publisher: Oxford University Press (OUP)
Date: 18-08-1983
DOI: 10.2307/1380380
Publisher: BirdLife Australia, Ltd.
Date: 2020
DOI: 10.20938/AFO37190199
Abstract: The populations of South Australian duck and wader species have recently decreased considerably, but their abundance at Bolivar Wastewater Treatment Plant in metropolitan Adelaide is poorly known. To help assess the importance of this site for ducks and waders, we made 25 trips to Bolivar between December 2018 and July 2020, during most of which time south-eastern Australia was experiencing a long dry period. On each trip, we observed between 11 and 26 species of ducks and waders, with a mean total of 9804 (range 2437–15,653) in iduals per trip. At times, we observed several thousand Pink-eared Ducks Malacorhynchus membranaceus, Grey Teal Anas gracilis, and Australian Shelducks Tadorna tadornoides, with occasionally up to 1200 Blue-billed Ducks Oxyura australis and 2000 Hardheads Aythya australis. Several wader species that largely breed in Australia’s semi-arid and arid zones were also observed, including occasionally Red-necked Avocets Recurvirostra novaehollandiae. Five species of waders that breed in the Northern Hemisphere were also recorded fairly regularly in the summer of both 2018–2019 and 2019–2020, including up to ~2000 Sharp-tailed Sandpipers Calidris acuminata, 2000 Red-necked Stints C. ruficollis and 150 Curlew Sandpipers C. ferruginea. These observations indicate that this wastewater treatment plant is a critically important refuge site for several species of ducks and waders. Every effort should thus be made to maintain this site for the conservation of these species in the future.
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/ZO09010
Abstract: This study examined the history, prevalence and distribution of sarcoptic mange in southern hairy-nosed wombats (Lasiorhinus latifrons) in the Murraylands, South Australia. Results from a survey suggested that there had been a long history of sporadic mange outbreaks, with 43% of 85 respondents indicating that they had seen diseased animals. There was a concentration of positive sightings (59%) in the vicinity of one town, Swan Reach. A total of 67 wombats was also caught on three pastoral properties 0% (n = 21), 4% (n = 21) and 76% (n = 23) were found to have mange at each respective site. Diseased wombats presented with erythema, parakeratosis and alopecia and had lower median condition, subcutaneous fat and higher bone prominence scores than healthy animals. Severely diseased adult wombats had an average bodyweight that was 9.86 kg lower than those without mange. Infected animals suffered higher mortality, with a rate of ~37% in eight months on one property. It is suggested that mange may have a significant effect on southern hairy-nosed wombats and outbreaks could result in the decline and/or possible extinction of small, isolated populations. Population management initiatives, including suspending culling quotas in infected populations, should thus be considered.
Publisher: Cambridge University Press (CUP)
Date: 08-1993
DOI: 10.1017/S0967199400001519
Abstract: The occurrence of in vivo parthenogenesis is documented for laboratory-bred in iduals of the Australian dasyurid marsupial, Sminthopsis crassicaudata . About 30% of females that had been isolated from males for a greater period of time than the length of pregnancy were found, on dissection of their uteri, to have embryos present. The embryos were surrounded by a mucoid coat and shell membrane and at least the first two cleavage isions occurred normally. After this time, however, unequal cleavage isions appeared to result. The parthenogenesis that takes place may be initiated as a result of activation of ageing ovulated oocytes. Its frequent occurrence may prove useful in a study of maternal and paternal contributions to early embryonic development in this species.
Publisher: S. Karger AG
Date: 1988
DOI: 10.1159/000146656
Abstract: The fine structure of epithelial cells of the small ventral prostate of i Pseudomys australis /i males was studied. The cells were sometimes binucleated, exhibited relatively little granular endoplasmic reticulum, generally few secretory granules (probably reflecting a low proteinaceous secretory activity) but had abundant agranular endoplasmic reticulum (AER) similar to that in steroidogenic cells. Some of the mitochondria also showed tubular cristae. Furthermore, most cells had some irregular dense bodies in the cytoplasm which may have developed, by a gradual transformation process, from the membranes of AER, mitochondria and other organelles they could be the product of degenerative changes in these organelles. These findings indicate a significant difference in the structure of these cells from those present in the ventral prostate of the hopping mouse, i Notomys alexis /i . It is speculated that this gland secretes relatively little protein but perhaps more lipid or cholesterol-derived substance.
Publisher: CSIRO Publishing
Date: 2018
DOI: 10.1071/AM16055
Abstract: Most of the Australian ‘old endemic’ rodents have greatly reduced distributions with several species now threatened with extinction. Application of assisted reproductive technology has the potential to assist in their conservation programs in at least a few species. Here we describe an attempt to cryopreserve spermatozoa from two of these species – those of the plains mouse (Pseudomys australis) and spinifex hopping mouse (Notomys alexis), which have dramatic differences in sperm morphology. Slow and rapid freezing and three different cryoprotectant media with either raffinose, glycerol and/or skim milk were used and the results compared with those of house mouse sperm, which were used as controls. Sperm morphology, motility, membrane integrity and DNA damage were determined. Prior to cryopreservation there was a higher percentage of morphologically normal, motile, P. australis sperm than in those from N. alexis. Following cryopreservation, regardless of treatment, the percentage of motile sperm was low but it was higher when raffinose with skim milk was used as a cryoprotectant than in raffinose with glycerol albeit that minimal differences in membrane integrity or DNA damage were evident. Raffinose with skim milk should thus be used as a cryoprotectant for storing sperm of these Australian rodents in the future.
Publisher: Wiley
Date: 07-1992
Abstract: Various morphological aspects of in vivo egg maturation and sperm-egg interaction were investigated in the Australian marsupial Sminthopsis crassicaudata with the transmission and scanning electron microscopes. Cortical granules invariably occurred in primary oocytes, with the number increasing after resumption of the first meiotic ision. They generally occurred close to the oolemma, including the region near the oocyte nucleus. After mating, spermatozoa with intact acrosomes, which had a homogeneous electron-dense matrix, were found on the outer zona surface, but loss of acrosomal contents had occurred by the time of zona penetration. Sperm incorporation into the egg took place at the metaphase II stage of meiosis, and, at this time, cortical granules disappeared from the egg cortex. Sperm heads with condensed chromatin in the egg cytoplasm had an electron-dense layer of subacrosomal material over part of the dorsal nuclear surface, but no membranes were present around these incorporated spermatozoa. Sperm chromatin decondensation resulted in an elevation of egg cytoplasm, and the cell membrane over this area lacked microvilli. The pronuclear envelope was not laid down until after chromatin decondensation had occurred. By this time the fertilized egg had reached the uterus, and a smooth, electron-dense, shell membrane had been deposited. These observations, together with our previous findings, indicate that some of the processes of sperm-egg interaction are similar to those in eutherian mammals, whereas others appear highly ergent.
Publisher: Bioscientifica
Date: 11-1982
Abstract: The relative size and histology of the testes of sexually active adult Pseudomys and Notomys differed markedly between species. Average weight of testes (as % of body wt) ranged from about 3% in P. australis and P. nanus to about 0.15% in most Notomys. In the testes of most species, interstitial tissue was relatively sparse, but in P. apodemoides, P. delicatulus and P. hermannsburgensis it was abundant and consisted of a mass of lipid-rich epithelioid Leydig cells. Seminiferous tubule diameters were similar in all species, but epididymides ranged from about 500 mg in weight (about 1% body wt) in P. australis to about 20 mg (about 0.05% body wt) in most Notomys. Likewise numbers of spermatozoa in the paired cauda epididymidis ranged from about 500 x 10(6) in P. australis and P. nanus to about 2 x 10(6) in 3 of 4 Notomys species.
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/ZO9920057
Abstract: Seven field trips to Curtin Springs Station, in the south of the Northern Territory (two in July and five in December-January), were carried out between July 1984 and January 1991 to investigate the reproductive activity of spinifex hopping mice in the natural environment. Gonadal activity was determined from most s les of animals collected. Pregnant animals were present on only one occasion (December 1988-January 1989), but two females collected in December 1985 had corpora lutea in their ovaries. Most adult males were, by contrast, sexually mature, as indicated by germ-cell associations in the seminiferous tubules, spermatozoa in the excurrent ducts, and secretion in the lumina of the ventral prostates and seminal vesicles. Nevertheless, the testes were invariably very small, 2-4 germ-cell associations were sometimes present in tubule cross-sections, epididymal spermatozoa were highly pleiomorphic and seminal vesicles minute. Such morphological traits are thus invariable features of the reproductive biology of males of this species.
Publisher: Bioscientifica
Date: 05-1971
Abstract: Gonadotropin-releasing hormone agonists (GnRHa) have gained increasing attention in the last decade as an alternative trigger for oocyte maturation in patients at high risk for ovarian hyperstimulation syndrome (OHSS). They provide a short luteinizing hormone (LH) peak that limits the production of vascular endothelial growth factor, which is the key mediator leading to increased vascular permeability, the hallmark of OHSS. Initial studies showed similar oocyte yield and embryo quality compared with conventional human chorionic gonadotropin (hCG) triggering however, lower pregnancy rates and higher miscarriage rates were alarming in GnRHa triggered groups. Therefore, two approaches have been implemented to rescue the luteal phase in fresh transfers. Intensive luteal phase support (iLPS) involves administiration of high doses of progesterone and estrogen and active patient monitoring. iLPS has been shown to provide satisfactory fertilization and clinical pregnancy rates, and to be especially useful in patients with high endogenous LH levels, such as in polycystic ovary syndrome. The other method for luteal phase rescue is low-dose hCG administiration 35 hours after GnRHa trigger. Likewise, this method results in statistically similar ongoing pregnancy rates (although slightly lower than) to those of hCG triggered cycles. GnRHa triggering decreased OHSS rates dramatically, however, none of the rescue methods prevent OHSS totally. Cases were reported even in patients who underwent cryopreservation and did not receive hCG. GnRH triggering induces a follicle stimulating hormone (FSH) surge, similar to natural cycles. Its possible benefits have been investigated and dual triggering, GnRHa trigger accompanied by a simultaneous low-dose hCG injection, has produced promising results that urge further exploration. Last of all, GnRHa triggering is useful in fertility preservation cycles in patients with hormone sensitive tumors. In conclusion, GnRHa triggering accompanied by appropriate luteal phase rescue protocols is a relatively safe option for patients at high risk for OHSS.
Publisher: Wiley
Date: 12-2011
DOI: 10.1111/J.1749-4877.2011.00264.X
Abstract: The Spinifex hopping mouse (Notomys alexis Thomas, 1922) is an arid adapted Australo-Papuan old endemic rodent that undergoes boom and bust population cycles. In this communication, we review our findings on the timing of reproduction and the potential reproductive rate of this species. To investigate the first question, the reproductive condition of adult females, and occurrence of immatures, in a population on a cattle station in central Australia was determined and, for the second, data from a laboratory colony compared to those previously published on closely related species in other environments. The findings show that, at least in the population at the times that monitoring was performed, reproductive activity was only taking place in spring and early summer, whereas the laboratory study indicates that females have a similar gestation length and litter size to those of most close relatives occurring in other environments. Males have extremely small testes and store relatively few sperm. The findings suggest that Notomys alexis might show some seasonality of reproduction at least in this region of central Australia and that this species does not have a higher reproductive rate than that of related species in other, more predictable, environments.
Publisher: Wiley
Date: 03-1983
Abstract: Actin was localized in the sperm head of the plains mouse, Pseudomys australis, using NBD-phallacidin, a fluorescent-labeled phallotoxin. It was found to be present in the two ventral hooks in sperm from the testis, epididymis, and vas deferens. Faint fluorescence was observed in other regions of the sperm head, whereas autofluorescence occurred in the midpiece of the tail in some preparations. The material in the ventral hooks was also found to be birefringent, which is consistent with it showing preferential orientation.
Publisher: Bioscientifica
Date: 09-1998
Abstract: In this study of brushtail possums, proteins present in epididymal fluid and not present in blood plasma and those that become associated with spermatozoa as they pass along the tract were investigated. At least 19 proteins were present in epididymal fluid in the various regions of the tract that were not detected in serum. Some of these may be present on the sperm plasmalemma. Six proteins were extracted from caput spermatozoa (M(r) 117,000, 103,000, 87,500, 85,000, 62,000 and 33,000) that did not appear in the caudal sperm extracts. Eight proteins (M(r) 50,000, 49,000, 32,000, 27,000, 26,500, 25,000, 24,500 and 18,000) were localized to caudal sperm extracts. These findings suggest that some sperm proteins are lost or modified, whereas others are added to the sperm plasma membrane during epididymal transit. In vitro incorporation of [35S]methionine by the epididymal tissue showed that the distal caput and corpus are the most active regions in the synthesis and secretion of proteins. Four caudal epididymal proteins (M(r) 72,000, 31,000, 26,500 and 21,000) were partially sequenced. Those of M(r) 31,000 and 26,500 had the same N-terminal amino acid sequence suggesting post-translational modification of the same protein they showed homology to a retinoic acid-binding protein. The protein of M(r) 72,000 was found to be homologous to alpha-fetoprotein, whereas the protein of M(r) 21,000 showed no significant homology to any protein in the database. These results show that the lumen of the epididymis has many proteins that are not present in the blood, some of which appear to become associated with spermatozoa during epididymal transit.
Publisher: CSIRO Publishing
Date: 1996
DOI: 10.1071/RD9960617
Abstract: This brief review summarizes our knowledge of the morphological events that are associated with oocyte maturation and fertilization in marsupials in which it has been suggested that there are marked differences from eutherians in both the developmental timetable of oocyte maturation and in some of the processes associated with sperm-egg interaction. Most of the data have been obtained from studies on four species: Monodelphis domestica, Sminthopsis crassicaudata, Sminthopsis macroura, and Trichosurus vulpecula. Differences between the species have been described for: (1) the arrangement of 'yolk' in the oocyte cytoplasm (2) the time of formation of cortical granules: (3) the mode of sperm penetration through the zone pellucida: (4) the sperm membrane involved in sperm-egg fusion: (5) the fate of inner acrosomal and sperm plasma membranes: and (6) the rapidity of sperm chromatin decondensation in the ooplasm. Such differences suggest considerable variation in these processes between different marsupial species although some of the variation described may be due to technical differences in the obtaining of the data. Thus, whether there are fundamental differences between the two major extant infraclasses of mammals, marsupials and eutherians, in some of the processes associated with fertilization is conjectural at the present time. The interspecific variation in the results obtained cautions one in extrapolating from observations on one or two 'model' species to the infraclass as a whole: a conclusion that might not, on reflection, be too surprising bearing in mind the long and separate evolutionary history of the major extant marsupial lineages.
Publisher: Wiley
Date: 18-10-2012
Publisher: Oxford University Press (OUP)
Date: 08-2000
Publisher: Wiley
Date: 10-1998
Publisher: Wiley
Date: 07-1999
Publisher: Bioscientifica
Date: 02-1969
Publisher: Wiley
Date: 14-05-2016
DOI: 10.1111/AZO.12129
Publisher: Elsevier
Date: 2006
Publisher: Wiley
Date: 02-1988
Abstract: The morphology of spermatozoa from the red veld rat, Aethomys chrysophilus, of Southern Africa is described two very different types were found, which came from animals from two separate, as-yet-undescribed, species. In in iduals from South Africa the sperm head had a somewhat disc-shaped nucleus and a large acrosome with a huge apical segment that, during epididymal transit, changed in form from initially projecting anteriorly to a highly complex structure that was flexed caudad and lay alongside part of the rest of the sperm head. In addition, the chromatin generally appeared to be not fully condensed. Spermatozoa from animals collected in Malawi were very different in morphology and had a head with a typical apical hook, a perforatorium, fully condensed chromatin, and a 4-micron-long ventral spur. Its sperm tail was also significantly longer. The time of ergence of these two groups of animals from a common ancestor is not known, but the present results show that a considerable morphological change in the sperm nucleus, acrosome, and subacrosomal space can evolve even between two, presumably closely related, species.
Publisher: Springer Science and Business Media LLC
Date: 07-2002
DOI: 10.1038/NATURE00832
Publisher: Wiley
Date: 14-06-2010
Publisher: CSIRO Publishing
Date: 2016
DOI: 10.1071/RD15425
Abstract: Spermatozoa exhibit considerable interspecies morphological variation across mammals, especially among murid rodents. In Australasia, most murids in the tribe Hydromyini have a spermatozoon with a highly complex head exhibiting an apical hook, characteristic of most murids, and two projections that extend from its upper concave surface, the ventral processes. In the present study we performed a phylogenetically controlled comparison of sperm morphology across 45 species of hydromyine rodents to test the hypothesis that the length and angle of both the apical hook and ventral processes, as well as the length of the sperm tail, increase with relative testes mass as a proxy for differences in levels of inter-male sperm competition. Although both sperm head protrusions exhibited considerable variation in their length and angle across species, only the angles increased significantly in relation to relative testes mass. Further, the length of the sperm flagellum was positively associated with relative testes mass. These results suggest that, in hydromyine rodents, the angle of the apical hook and ventral processes of the sperm head, as well as the sperm tail length, are likely to be sexually selected traits. The possible functional significance of these findings is briefly discussed.
Publisher: Oxford University Press (OUP)
Date: 08-2000
DOI: 10.1095/BIOLREPROD63.2.629
Abstract: The sperm head of the plains rat, an Australian hydromyine rodent, is highly complex in structure and contains, in addition to an apical hook, two large ventral processes (VPs) that extend from its upper concave surface and that are largely composed of a huge extension of the sperm head cytoskeleton surrounded by postacrosomal dense lamina. In this study we have attempted to determine their protein composition. For this, the VPs were isolated, the proteins within them separated by SDS-PAGE, and the resultant polypeptide bands Western blotted and probed with antibodies against laboratory rat perforatorial and bull perinuclear theca sperm proteins. Antibodies were also used to determine the perforatorial and perinuclear theca proteins by immunogold labeling of transmission electron microscopic sections. The results indicate that the material within the VPs is largely composed of perforatorial cross-reacting proteins together with F-actin with the dominant protein being PERF 15. The perinuclear theca proteins are, by contrast, restricted to a narrow region adjacent to the acrosomal and nuclear membranes. In conclusion, this study has shown that the VPs of the spermatozoa of Australian rodents are perforatorial-like appendages that contain similar proteins to the perforatorium of the apical hook together with F-actin their functional significance remains unknown.
Publisher: Wiley
Date: 2004
DOI: 10.1002/JMOR.10228
Abstract: The murine rodents are the most speciose subfamily of mammals. Here the morphology of the spermatozoon, as determined by scanning and transmission electron microscopy of representative species from four Eurasian clades, is described. Much interspecific variability in all components of the spermatozoon was found to occur, although most species have a bilaterally flattened sperm head with a single apical hook of variable length and orientation. Ultrastructural observations indicate that this apical hook invariably contains a nuclear projection as well as a large extension of the subacrosomal cytoskeleton, as a perforatorium rostrally, and a complex asymmetrical acrosomal extension. These spermatozoa also have relatively long tails that are attached to the lower concave surface of the sperm head. Uniquely, in species in the Apodemus clade, the apical hook is orientated caudally. In a few species a highly derived sperm head morphotype that does not contain an apical hook is present. These sperm heads vary in morphology from being globular in two species of Bandicota, to bilaterally flattened and paddle-shaped in Tokudaia and Micromys. In spermatozoa of the latter two genera the subacrosomal cytoskeleton, which is less extensive than in species with a hooked sperm head, forms an apical extension, but that is not the case in Bandicota. In all species where the sperm head lacks an apical hook the acrosome is more symmetrical. The sperm tail is much shorter in these species, with attachment to the head occurring on the ventral surface in Tokudaia and basal in Micromys and the two species of Bandicota. As the sperm head morphotype with a complex apical hook is present in all the major clades of murine rodents, it is likely to be a plesiomorphic character within each of these clades, with the nonhooked sperm heads, which vary greatly in structure between species of the different lineages, probably being independently derived. The ultrastructural organization of the sperm head of Bandicota, but not those of Micromys or Tokudaia, suggest ergence in some of the morphological events associated with sperm-egg interaction at the time of fertilization.
Publisher: Wiley
Date: 02-1988
Abstract: The aim of the present study was to determine the morphological changes that take place in the male and female gametes during in vivo fertilization in the Australian marsupial, the fat-tailed dunnart, Sminthopsis crassicaudata. Plastic sections were cut of sperm and eggs recovered from the oviducts of recently mated in iduals, and light microscopy of thick, and transmission EM of thin, sections was carried out. It was found that, before penetration of the zona, the spermatozoon came to lie along the outer surface with its rostral tip forming a depression in the zona substance. During penetration, zona material was packed tightly around the spermatozoon, and no large hole was formed. A spermatozoon within the perivitelline space had made contact with the oolemma by way of its apical tip. In a spermatozoon partly incorporated into the ooplasm, fusion appeared to have taken place between its plasma membrane and that of the oolemma. Mucoid coat material became deposited outside the zona at this time its existence and/or the release of cortical granule content probably prevented polyspermy. Once inside the egg cytoplasm, the sperm head sometimes travelled a considerable distance before chromatin decondensation occurred. In addition, it appeared to rotate somewhat on its axis at this time. Finally, some membranous structures were found around two condensed sperm heads in the ooplasm, which may have been part of the pronuclear envelope. Thus this study on in vivo fertilization in the dunnart documents, for the first time, some aspects of fertilization in an Australian marsupial as seen with the transmission electron microscope it indicates a few differences from those previously found for the American opossum.
Publisher: CSIRO Publishing
Date: 2008
DOI: 10.1071/RD07128
Abstract: β1,4-Galactosyltransferase-I (GalTase-I) is one of the key molecules on the sperm surface of eutherian mammals that is likely to be involved in binding to the egg coat, the zona pellucida, to mediate sperm–egg interaction. In laboratory mice, the species for which most data are available, this protein functions as a receptor for the zona pellucida protein ZP3 of the oocyte and, upon binding, triggers the sperm acrosome reaction. In the present study, we investigated the presence and abundance of GalTase-I in epididymal sperm extracts of a marsupial, the brushtail possum, Trichosurus vulpecula. For this, spermatozoa were collected from cauda epididymides and the amount of β1,4-galactosyltransferase activity in washed sperm extracts was compared with that of porcine spermatozoa. Overall β1,4-galactosyltransferase enzyme activity was found to be more abundant in possum sperm extracts than those from porcine spermatozoa (P 0.05). Immunoblots with an antibody to mouse GalTase-I revealed that the molecular weight of possum spermatozoa GalTase-I was 66 kDa, which is similar to the molecular weight of GalTase-I in spermatozoa from eutherian mammals. The molecular weight of GalTase-I was the same in sperm extracts collected from the caput and cauda epididymides. These results demonstrate that GalTase-I is indeed present in possum spermatozoa and thus it may be a gamete receptor molecule on the sperm surface of marsupials as well as those of eutherian mammals.
Publisher: Bioscientifica
Date: 03-2001
Abstract: The flagellum of a mammalian spermatozoon consists of a central axoneme surrounded by two cytoskeletal structures, the outer dense fibres and the fibrous sheath, which may aid in sperm motility or stability. In this study the outer dense fibres and fibrous sheath were isolated and partially characterized in a marsupial species, the brushtail possum (Trichosurus vulpecula). Spermatozoa from the cauda epididymidis were decapitated by sonication, and the head and tail fractions were separated by centrifugation over a 20, 40 and 60% (w/v) sucrose density gradient. After confirming sperm tail purity by Nomarski microscopy, the tails were incubated in either SDS-dithiothreitol to isolate the outer dense fibres or urea-dithiothreitol to isolate the fibrous sheaths. Purified outer dense fibres and fibrous sheaths were solubilized in SDS and beta-mercaptoethanol and proteins were separated by one-dimensional PAGE. Coomassie blue staining showed that the outer dense fibres were composed of seven major proteins (molecular masses: 73, 58, 55, 54, 52, 41 and 16 kDa), and the fibrous sheath was composed of 12 major proteins (molecular masses: 106, 76, 66, 62, 55, 53, 52, 46, 40, 30, 28 and 16 kDa). A polyclonal antibody to the fibrous sheath proteins showed strong crossreactivity with those of fibrous sheath from spermatozoa of several other marsupial species, as well as those from laboratory rats. Subsequent western blotting identified the immunoreactive 76 and 62 kDa proteins from all species, thus indicating their high conservation between species. No crossreactivity of the fibrous sheath antibody to any other cytoskeletal structures, including the outer dense fibres, mid-piece fibre network or connecting laminae, or to the acrosome or underlying subacrosomal material, was evident, indicating that the fibrous sheath proteins are localized to this structure alone. Further work is in progress to determine the extent of homology of these proteins to those in eutherian mammals.
Publisher: Bioscientifica
Date: 09-1993
Abstract: The morphology and structural organization of unusual spermatozoa from two species of bandicoot rats (Bandicota spp) from Southern Asia were studied with the light and transmission electron microscope. Unlike those described for nearly all other eutherian species the heads of Bandicota savilei and B. indica spermatozoa were bulbous or globular in shape and had no narrow uniformly defined apex nor a clearly delineated perforatorium. The nucleus, which had one or more prominent vacuoles, was capped by a huge, bulky, acrosome with no obvious morphologically recognizable equatorial segment. The postacrosomal dense lamina was extremely short and a posterior ring lay anterior to the caudal pole of the nucleus. In addition, the tail of the spermatozoon was only 28-45 microns in length. The organization of the spermatozoon of these two species of Bandicota is thus quite unlike that described for any other murid rodent or even mammalian species. Its highly ergent features suggest that the processes of zona penetration and incorporation of the fertilizing spermatozoon into the egg may differ markedly from those of all eutherians so far investigated.
Publisher: Wiley
Date: 12-1991
Abstract: The distribution of filamentous actin around the maturing sperm head and in spermatozoa of four species of Australian conilurine rodents was investigated at the light and electron microscopic levels. Similar results were obtained for all the species studied. Mechanically isolated spermatids had NBD-phallacidin-positive longitudinal bands of fluorescence over the dorsolateral surface and, in late spermatids, bands of bright fluorescence passed perpendicularly from the dorsal convex to ventral concave surface. TEM observations indicated that these regions corresponded to filaments of ectoplasmic specializations and granular filamentous material around the tubulobulbar complexes, respectively. In testicular and cauda spermatozoa NBD-phallacidin fluorescent material was present in the two ventral processes that extended from the upper concave surface of the sperm head also fainter material occurred along the concave border and as a dorsocaudal spur. Its distribution was identical for testicular and cauda spermatozoa. TEM of late spermatids showed that in the ventral process closest to the apical hook there were between 170 and 245 filaments, which attached to the inner surface of the postacrosomal dense lamina in the more caudal ventral process about 70 filaments occurred. No filaments were, however, visible in the mature spermatozoon but, after immunocytochemical labelling for actin, deposition of gold particles was evident over ventral processes of both late spermatids and cauda spermatozoa. Within the female tract these ventral processes made contact with the zona matrix and were taken into the egg cytoplasm unchanged in morphology. The possible functional significance of the filamentous actin in these structures is discussed.
Publisher: Springer Science and Business Media LLC
Date: 02-1983
DOI: 10.1007/BF00207701
Abstract: We aimed to evaluate the safety and feasibility of laparoscopic total extraperitoneal (TEP) inguinal hernia repair in patients with the continuation of their antithrombotic agents. This was prospective cohort study. A total of 115 patients who underwent TEP inguinal hernia repair between January 2015 and September 2016 were included in the analysis. Seventeen patients continued their antithrombotics (antithrombotic group) the other 98 had not been on antithrombotics (control group). The analysis was performed by using Mann-Whitney U-test, Chi-square or Fisher's exact test. The antithrombotic group had a greater mean age (65.9 ± 8.0 vs. 57.7 ± 13.6,P= 0.002) and higher prevalence of hypertension (64.7% vs. 33.7%,P= 0.015), cardiovascular diseases (64.7% vs. 7.1%,P < 0.001), atrial fibrillation (23.5% vs. 0,P < 0.001), ischaemic heart disease (35.3% vs. 0,P < 0.001) and the American Society of Anaesthesiologists ≥2 (94.1% vs. 81.6%,P= 0.005). The operation time for the antithrombotic group was longer than that of the control group (92.06 ± 32.81 min vs. 72.33 ± 20.99 min,P= 0.015). None experienced conversion to open surgery in either group. There was no difference in the post-operative complications (29.4% vs. 28.6%) and sero-haematoma formation (23.5% vs. 11.1%). The analgesic requirement, hospital stays (23.72 ± 7.74 vs. 22.35 ± 10.33 h) and the time for return to normal daily activity (3.56 ± 1.74 vs. 3.63 ± 1.90) were not statistically different between the two groups. None in either group experienced major cardiovascular events within 30 days. Laparoscopic TEP inguinal hernia repair can be safely performed in patients with the continuation of their antithrombotic agents in experienced hands.
Publisher: Bioscientifica
Date: 03-1972
Abstract: Saline flushings from the uterine horns of rats with unilateral silk sutures (IUD's) were obtained at pro-oestrus, oestrus and on Day 5 of pseudopregnancy, and examined chemically. Protein and reducing sugar were invariably present and significantly increased in horns containing an IUD. The number of protein bands identified by disc electrophoresis varied between in idual animals, but showed no marked differences between the experimental and control horns at either pro-oestrus or oestrus. Among enzymes, amylase activity was consistently raised on the IUD side compared with the control side it was also significantly higher in the IUD horn during pseudopregnancy than in the control horns at pro-oestrus and oestrus. Lysozyme activity was found at pro-oestrus in IUD horns but not in the control horns at oestrus and during pseudopregnancy little activity was measurable. Proteinase activity, using haemoglobin as substrate, was significantly increased in IUD horns at acid pH, but undetectable at pH 7·7 with casein as substrate at pH 7·7, activity was usually present but did not vary significantly between the two sides. Trypsin activity was also measurable at pH 7·7, but was unchanged in the presence of an IUD. Ribonuclease and phosphatase were usually detectable at pro-oestrus and oestrus, but their activities were not significantly altered by an IUD on Day 5 of pseudopregnancy, however, much lower levels were found in both horns. Neither hyaluronidase nor neuraminidase could be detected in any flushings assayed. The possible biological implications of these findings are discussed.
Publisher: CSIRO Publishing
Date: 1997
DOI: 10.1071/ZO97011
Abstract: The head of the spermatozoon in eutherian mammals contains a nucleus, acrosomal cap and cytoskeleton. It is generally spatulate, paddle-shaped or pear-shaped, but in most murid rodents it is hook-shaped with the anterior region of the nucleus surrounded by an elaborate acrosome and an extension of the subacrosomal cytoskeleton as a perforatorium. This type of spermatozoon is present in Australasian Rattus, together with several other New Guinean genera. However, in most Australasian hydromyine rodents a far greater complexity of structural organisation of the sperm head has evolved in which two further elaborate processes extend from its upper concave surface. These processes contain a huge extension of the cytoskeleton within which filamentous actin is present. By contrast, the form of the sperm head in a few species of Pseudomys, Notomys and Solomys is highly ergent and is either truncated, spatulate or pear- shaped. The evolutionary trends of change in sperm head shape are discussed and it is suggested that the falciform sperm head with the two extra processes in most of the hydromyine rodents is one of the most morphologically complex sperm head types to have evolved in eutherian mammals it contains a far more extensive development of the cytoskeleton than that of any other mammalian spermatozoon.
Publisher: CSIRO Publishing
Date: 1997
DOI: 10.1071/ZO97010
Abstract: When testis mass is plotted against body mass for Australasian rodents, an allometric relationship is found to occur. Nevertheless, considerable interspecific variability in testis mass as a percentage of body mass is evident for the different species, with the smallest relative size of testes in the Australian rodents being present in most Notomys and several Pseudomys species. In other Pseudomys, and nearly all species of the other genera, the relative size of testes is considerably greater. Notomys and Pseudomys with small testes tend to have a lower relative volume of seminiferous tubules to the total testicular mass than species with relatively large testes. These species also generally have small cauda epididymides and a less dense sperm population in this region. The data thus clearly indicate far fewer sperm are produced, and stored, in the male reproductive tract of these animals. The causative reason(s) for the differences in relative testis size are discussed and the possibility that it relates to variation in breeding system, and hence potential intermale sperm competition, is considered. However, the scant data available do not indicate an obvious association among these parameters. It is thus suggested that, in Notomys at least, the relatively small testes may relate to the other ergent features of the reproductive tract one of the consequences of which may be a highly efficient sperm-transport system.
Publisher: Wiley
Date: 24-04-2018
DOI: 10.1111/AVJ.12690
Abstract: This study reports necropsy findings of koalas from the Mount Lofty Ranges region in order to identify health threats to this mainland South Australian population. Koalas from the Mount Lofty Ranges region (n = 85) that had died or been euthanased on welfare grounds were examined at necropsy during 2012-13 at the School of Animal and Veterinary Sciences, University of Adelaide. Disease findings, approximate age, sex and body condition of koalas were recorded. Histopathological examination was undertaken on gross lesions and in suspect cases, skin scrapings taken for microscopy and PCR performed for Chlamydia pecorum detection. Traumatic injury was the most common necropsy finding (48/85 57%), caused by motor vehicle accidents (35/48 73%), canine attacks (11/48 23%) or bushfire burns (2/48 4%). Oxalate nephrosis (27/85 32%) was also more common than other conditions. Infectious diseases included chlamydiosis (10/85 12%) and sarcoptic mange (7/85 8%). Marked testis asymmetry was evident in 11% (6/56) of males, with histopathology suggestive of atrophic change in four animals. Other pathological conditions included gastrointestinal disease (7/85 8%) and respiratory disease (3/85 4%). Almost half of the koalas (38/85 45%) were found to have two or more abnormalities at necropsy. This study found trauma, mainly from motor vehicle accidents, and oxalate nephrosis to be the predominant causes of death and/or disease in koalas from the Mount Lofty Ranges region. Recent emergence of both clinical chlamydiosis and sarcoptic mange has also occurred, providing insight into the health status and causes of disease or injury in this South Australian mainland koala population.
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/AM15055
Abstract: Significant gaps in knowledge currently exist regarding the small mammal fauna of the Northern Kimberley (NOK) bioregion. Theda Station is a previously unsurveyed pastoral lease in the NOK. The aim of the current study was to determine the presence of small mammals (non-volant, kg) on Theda Station and to compare these findings with those recently obtained on the adjacent Doongan Station. Between 2006 and 2014, 226 site surveys were conducted across 69 sites, with over 26 000 trap-nights encompassing a range of habitats. Thirteen of the 27 small mammal species known to occur in the NOK were detected. Four species (Pseudomys nanus, Rattus tunneyi, Zyzomys argurus and Sminthopsis virginiae) were common, five (Pseudomys delicatulus, Pseudantechinus ningbing, Dasyurus hallucatus, Isoodon macrourus and Petropseudes dahli) were detected less frequently, and four (Leggadina lakedownensis, Hydromys chrysogaster, Planigale maculata and Petaurus breviceps) were occasionally recorded. Our study provides important baseline data for small mammals in this region. It highlights the lack of detailed knowledge of both the presence of, and temporal fluctuations in, the region’s small mammal fauna. This study supports a non-uniform distribution of the small mammal fauna across the NOK, with Theda Station lying within a transition zone between the high rainfall rugged coastal and near-coastal areas and the lower rainfall areas of the east.
Publisher: Wiley
Date: 08-1988
Publisher: Wiley
Date: 11-2009
DOI: 10.1111/J.1095-8649.2009.02361.X
Abstract: The spawning biomass of Australian anchovy Engraulis australis in gulf and shelf waters of South Australia was compared using the daily egg production method (DEPM). The total survey area was 128 700 km2 with recorded spawning areas in gulf and shelf waters of 4898 and 44 618 km2, respectively. High egg densities in the warm, shallow gulf waters were produced by small, young (<1 year old) E. australis that spawned relatively small batches of eggs (c. 855) approximately every 3 days. In cooler, deeper shelf waters, where larger, older E. australis are found, lower egg densities occurred despite in iduals producing much larger batches of eggs (c. 15,572) approximately every 7 days. In shelf waters, the highest densities were recorded at inshore s ling stations. Spawning appeared to peak between 0000 and 0100 hours. Females were more abundant than males in s les from both gulf and shelf waters with sex ratios of 0.61 and 0.56, respectively. The spawning biomass of E. australis in shelf waters was 101 522 t, whereas the estimate for gulf waters was 25 374 t. Due to the differences in mean size of the spawning females, however, c. 6x10(9)E. australis were present in each region. The results support the hypothesis that variability in habitat conditions may directly influence E. australis reproduction. A large reserve of young fish in the relatively stable gulf environment may increase the resilience of the E. australis population in South Australia to unfavourable interannual changes in offshore environmental conditions.
Publisher: CSIRO Publishing
Date: 2009
DOI: 10.1071/SRB09ABS115
Abstract: Introduction: The aim of the present study was to determine the immediate effects of whole body heating on sperm numbers, motility and apoptosis. Material and Methods: C57BL/6 mice (n=7) were exposed to 37-38oC (8 hours/day), for three consecutive days while control mice (n=7) were kept at 23-24oC. Caudal epididymal spermatozoa were collected from control and heat treated mice 16 hours after the last heat treatment to determine the sperm number and motility using a Neubauer haemocytometer and sperm apoptotic changes by dual colorflow cytometry using Annexin V/PE (Annexin V conjugated with phycoerythrin) and 7AAD (7-amino-actinomycin D) stains. Results: There were no significant differences (p .05) in sperm numbers between heat treated and control mice, however heating did result in a significant reduction in sperm motility (p .05). Apoptosis staining identified four different subpopulations of spermatozoa: (a) live spermatozoa (Annexin V-/7AAD-), (b) early apoptotic spermatozoa with exteriorized phosphotidylserine (PS) receptor and intact plasmalemma (Annexin V+/7AAD-), (c) late apoptotic spermatozoa with PS receptor translocation and leaky plasmalemma (Annexin V+/7AAD+) and (d) dead spermatozoa with damaged plasmalemma with no detectable PS receptor (Annexin V-/7AAD+). Heating resulted in significant reduction in the percentage of live spermatozoa (p .05), an increase in early apoptotic (p .05), late apoptotic (p .05), and dead spermatozoa (p .05). Conclusion: This study shows that mice exposed to whole body heat exposure of 37-38oC for 8 hours per day for three consecutive days exhibited early and late apoptotic changes to epididymal spermatozoa. These findings suggest possible adverse effects of exposure to high temperature on the viability of human spermatozoa in the epididymides. In addition, these findings reinforce the importance of temperature during sperm preparation procedures in infertility clinics, and research laboratories.
Publisher: Wiley
Date: 02-1999
DOI: 10.1002/(SICI)1097-0185(19990201)254:2<214::AID-AR7>3.0.CO;2-F
Publisher: CSIRO Publishing
Date: 1978
DOI: 10.1071/ZO9780475
Abstract: Ovulation rates, as determined by the number of recently formed corpora lutea, and oestrous cycle lengths have been determined for several species of native Australian rats (Rattus spp.) from erse habitats. Ovulation rates vary significantly between species: R. leucopus cooktownensis had the lowest ovulation rate those for two subspecies of R. fuscipes, R. lutreolus lutreolus, R. tunneyi tunneyi, R. sordidus sordidus and R. sordidus colletti were significantly higher and all similar to each other the highest ovulation rate occurred in R. sordidus villosissimus. However, all species of rats had short, 4- to 6-day, oestrous cycles. The possible ecological and evolutionary significance of these findings is briefly discussed.
Publisher: Bioscientifica
Date: 2002
Abstract: In this review, the biochemical composition and structural organization of the marsupial and eutherian zonae pellucidae are compared. Differences between the zonae from these two groups of mammals are observed in their response to dilute proteases and reducing agents, in their potential glycosylation patterns, and in some of their functions. However, studies on the glycoconjugates and polypeptides of the three zona pellucida genes have not explained these different responses to the proteases and reducing agents. There is high sequence similarity between the zona polypeptides of marsupials and eutherians, as well as a similarity in the oligosaccharides present, as demonstrated by lectin staining. As the marsupial and eutherian lineages erged from a common ancestor over 100 million years ago, these observations indicate that the three-dimensional structure of these glycoproteins is highly conserved throughout all mammals, although the complexity of its molecular organization has yet to be resolved. Phylogenetic analyses indicate that there are at least four groups of paralogous zona pellucida genes in vertebrates. The marsupial ZPA and ZPB genes have been named in accordance with their orthologues but the phylogenetic relationships of the marsupial ZPC gene require further investigation.
Publisher: Wiley
Date: 15-06-1997
DOI: 10.1002/(SICI)1097-010X(19970615)278:3<133::AID-JEZ2>3.0.CO;2-P
Abstract: We are examining the extracellular coats of the brush-tailed possum as a possible target for an immunocontraceptive vaccine for biocontrol of this pest species in New Zealand. In this study we have compared the composition of the extracellular coats of the fat-tailed and stripe-faced dunnarts, brush-tailed possum, domestic rabbit, and laboratory mouse using histochemistry, immunocytochemistry, and immunofluorescence. The histochemistry of the luminal epithelium of the oviduct and mucoid coats of the marsupials and rabbit indicated that they contain acidic glycoproteins. Immunofluorescence showed that polyclonal antiserum raised against the extracellular coats of the oocyte and early embryo of the fat-tailed dunnart, cross-reacted with the extracellular coats of the oocytes of all five species. These results suggest that there are common epitopes on the extracellular coats of oocytes and early embryos of distinctly related therian species. Further work to characterise these proteins is required to determine whether there is close homology between the oviductal glycoproteins of these species.
Publisher: Wiley
Date: 15-02-2005
DOI: 10.1111/J.1365-2605.2005.00529.X
Abstract: In the greater bandicoot rat, Bandicota indica, of south-east Asia, nine cell associations were documented in the testicular seminiferous epithelium. In about 10% of the tubule cross sections two or more cell associations occurred and, furthermore, some of the generations of germ cells within the cell associations were sometimes either out of phase, or missing, in the tubule cross sections. These features, together with the fact that this species has a highly pleiomorphic sperm head shape, are somewhat reminiscent of those of the seminiferous epithelium in humans and some other primates but not of common laboratory rodents. This species could thus be a good model for investigating irregular patterns of spermatogenesis in naturally occurring wild species of rodent.
Publisher: Wiley
Date: 22-07-2020
DOI: 10.1111/JZO.12813
Publisher: Elsevier BV
Date: 07-1973
Publisher: Wiley
Date: 07-04-2020
DOI: 10.1111/JZO.12779
Publisher: Wiley
Date: 14-05-2014
DOI: 10.1002/JMOR.20295
Publisher: Wiley
Date: 1994
Abstract: The organization of sperm chromatin in the dasyurid marsupial, Sminthopsis crassicaudata, was investigated using various morphological techniques. Transmission electron microscopy indicates two quite distinct chromatin regions became evident late in spermiogenesis with an outer globular region containing blocks of very electron-dense chromatin. Fluorescent light microscopical studies after staining with DNA dyes and 7-amino actinomycin D of testicular, caput, and cauda epididymal spermatozoa showed that this region fluoresced less brightly than the rest of the nucleus, indicating the presence of fewer DNA binding sites. Freeze fracture showed that the chromatin in most of the nucleus had randomly arranged particles of various sizes, but that of the outer region was composed entirely of small particles. This outer region was more resistant to low concentrations of the ionic detergent, SDS, whereas both guanidine hydrochloride and urea together with sodium chloride generally dispersed all the chromatin except that in the outer globular region and in a localized area of the nucleus beneath the acrosome. This study has thus revealed that the outer globular chromatin of these spermatozoa responds differently to ionic detergents and protein denaturing agents and has a different chromatin organization than most of the rest of the nucleus. The significance of these differences remains, however, to be determined.
Publisher: Oxford University Press (OUP)
Date: 02-1972
DOI: 10.2307/1378841
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/WR16152
Abstract: Context Boom and bust population cycles are characteristic of many arid-zone rodents, but it is unknown to what extent these dynamics might be influenced by the presence of invasive rodents, such as the house mouse (Mus musculus) in Australia. Aim To determine whether the presence of M. musculus can have negative consequences on the population abundance and reproduction of two old Australian endemic rodents (the spinifex hopping mouse, Notomys alexis, and sandy inland mouse, Pseudomys hermannsburgensis). Methods The study took place on the sand dunes of a cattle station in central Australia. Population abundance was estimated as the number of in iduals caught in small mammal traps, and female reproductive condition by external examination and, in a few cases, euthanasia and inspection of the reproductive tract. Key results Two synchronous periods of high abundance of N. alexis and M. musculus occurred several months after significant rainfall events, whereas the abundance of P. hermannsburgensis was consistently low. No reproduction took place in N. alexis or M. musculus when populations had reached high abundance. During low-rainfall periods, M. musculus was not detected on the sand dunes, and the two endemic species were sparsely distributed, with reproduction occasionally being evident. Conclusions During dry periods, M. musculus contracted back to refuges around the homestead and, after significant rainfall, it expanded onto the sand dunes and became abundant at the same time as did N. alexis. In contrast, and unlike in areas where M. musculus was generally rare, P. hermannsburgensis always remained at a low abundance. These patterns suggest that in areas of the natural environment close to human-modified sites, populations of at least one species of an old endemic rodent are supressed by the presence of M. musculus. Reproduction did not occur in the old endemics at times of high M. musculus abundance, but did take place in spring/early summer, even in some dry years. Implications The spread of M. musculus into the Australian arid zone may have had negative impacts on the population dynamics of P. hermannsburgensis. These findings suggest that the presence of human settlements has resulted in refuges for house mice, which periodically spread out into the natural environment during ‘boom’ times and adversely affect the natural population cycle of ecologically similar species such as P. hermannsburgensis.
Publisher: Wiley
Date: 28-04-2014
DOI: 10.1111/VCP.12145
Abstract: Oxalate nephrosis is a highly prevalent disease in the Mount Lofty Ranges koala population in South Australia, but associated clinicopathologic findings remain undescribed. The aims of this study were to determine plasma biochemical and urinalysis variables, particularly for renal function and urinary crystal morphology and composition, in koalas with oxalate nephrosis. Blood and urine s les from Mount Lofty Ranges koalas with oxalate nephrosis were compared with those unaffected by renal oxalate crystal deposition from Mount Lofty and Kangaroo Island, South Australia and Moggill, Queensland. Plasma and urine biochemistry variables were analyzed using a Cobas Bio analyzer, and urinary oxalate by high-performance liquid chromatography. Urinary crystal composition was determined by infrared spectroscopy and energy dispersive X-ray analysis. Azotemia (urea > 6.6 mmol/L, creatinine > 150 μmol/L) was found in 93% of koalas with oxalate nephrosis (n = 15). All azotemic animals had renal insufficiency (urine specific gravity [USG] < 1.035), and in 83%, USG was < 1.030. Koalas with oxalate nephrosis were hyperoxaluric compared with Queensland koalas (P < .01). Urinary crystals from koalas with oxalate nephrosis had atypical morphology and were composed of calcium oxalate. Mount Lofty Ranges koalas unaffected by renal oxalate crystal deposition had renal insufficiency (43%), although only 14% had USG < 1.030 (n = 7). Unaffected Mount Lofty Ranges and Kangaroo Island koalas were hyperoxaluric compared with Queensland koalas (P < .01). Koalas with oxalate nephrosis from the Mount Lofty Ranges had renal insufficiency, hyperoxaluria, and pathognomonic urinary crystals. The findings of this study will aid veterinary diagnosis of this disease.
Publisher: CSIRO Publishing
Date: 1981
DOI: 10.1071/ZO9810589
Abstract: In the hopping-mouse, following a postpartum mating, embryos enter the uterus on about day 5. Implantation occurs on about day 7 if there are no suckling pups, but zona-free blastocysts may remain up to day 18 if from four to seven suckling pups are present. Implantation is eccentric and initially involves interdigitation of trophectoderm and uterine epithelial cells, followed by epithelial cell displacement. The orientation is antimesometrial and, during further development, the embryo invaginates into the yolk-sac cavity. In the ovary, corpora lutea develop during the first few days of pregnancy and then remain unchanged in size or cellular morphology until implantation, regardless of the length of its delay. Peripheral progesterone levels likewise show little change during the preimplantation period. After implantation, a similar number of corpora lutea are found but they increase progressively in size due to luteal cell hypertrophy. The cells show all the organelles typical of steroid hormone synthetic activity and there is a corresponding increase in blood progesterone levels at this time. Vesicular follicles are present throughout concurrent pregnancy and lactation and are larger after implantation. There is no evidence of spontaneous ovulation except at the time of parturition.
Publisher: CSIRO Publishing
Date: 2019
DOI: 10.1071/RD19034
Abstract: The organisation of the ovarian interstitial tissue in the southern hairy-nosed wombat Lasiorhinus latifrons was investigated. Unlike in most other marsupials, the outer cortical region of the ovary contains abundant luteinised interstitial tissue that largely occurs in discrete lobules, many of which contain a localised area of non-cellular, highly eosinophilic and periodic acid-Schiff-positive material. The findings suggest that the latter arises from the zona pellucida that surrounded the oocyte in growing follicles and that the luteinised interstitial tissue thus developed from transformed theca interna of degenerated atretic follicles. It is hypothesised that this tissue synthesises and secretes progestogens, which may result in the long, and variable, oestrous cycle length that has been found to occur in this species.
Publisher: Wiley
Date: 02-1999
DOI: 10.1002/(SICI)1098-2795(199902)52:2<174::AID-MRD8>3.0.CO;2-7
Publisher: Bioscientifica
Date: 06-1970
Abstract: Reestablishing blood flow and allowing the continuation of root development are some of the objectives of pulp revascularization. This procedure is currently indicated for teeth with incomplete root formation as an alternative to the traditional treatment of apecification, which consists of inserting calcium hydroxide paste into the root canal for a determined time period in order to induce the formation of a calcified barrier. Although it is considered as the most classically employed therapy, the permanence of the paste for long time periods may lead to the weakening of the root due to hygroscopic properties, as well as proteolytic activities of calcium hydroxide. Therefore, there has been a permanent search for alternatives which allow the full development of immature teeth. Revascularization has emerged as such an alternative, and a range of treatment protocols can be found in the scientific literature. The aim of this paper is to accomplish a literature review concerning this issue.
Publisher: CSIRO Publishing
Date: 1995
DOI: 10.1071/RD9951129
Abstract: In order to gain some understanding of the significance of the morphological features of spermatozoa within the Macropodoidea, the motility of spermatozoa from two macropodids (Petrogale xanthopus and Dendrolagus matschiei) and the motility, number and distribution of spermatozoa from three potoroidids (Aepyprymnus rufescens, Bettongia penicillata and Potorous tridactylus) were examined. Sperm were collected by electro-ejaculation or from the cauda epididymides. Epididymides from the potoroidids were ided into 12 regions. One epididymidis per animal was fixed for light and transmission electron microscopy and, on the contralateral side, the number of sperm, their distribution and motility were determined. In general, spermatozoa of all five species differed markedly from one another in head and flagella dimensions. Spermatozoa from B. penicillata and P. tridactylus were significantly longer and broader and had a smaller acrosome relative to head length, and there was a radial displacement of dense fibres. They also progressed more rapidly in standard culture media. Spermatozoa from at least three species were able to alter their motility pattern in vitro as media viscosity increased. Sperm movement in all species appeared to be restricted to one plane and showed no evidence of rotation, whereas lateral head displacement was often pronounced there was no evidence of a sinusoidal mode of progressive motility. Testicular and epididymal sperm numbers in A. rufescens and P. tridactylus were relatively high (approximately 17.5-50 x 10(6)). In A. rufescens, approximately 69% of all epididymal sperm were located in the cauda epididymidis compared with approximately 40% in P. tridactylus. This study demonstrated that marked radial displacement of the dense fibres is probably closely associated with the ability to develop a sinusoidal mode of progressive movement, and that this feature of the sperm tail structure is not just linked with sperm size. Sperm size, however, is associated with sperm velocity.
Publisher: Wiley
Date: 12-1980
DOI: 10.1038/ICB.1980.63
Abstract: Peripheral T-cell lymphoma comprises a heterogeneous group of mature non-Hodgkin lymphomas. Their diagnosis is challenging, with up to 30% of cases remaining unclassifiable and referred to as "not otherwise specified". We developed a reverse transcriptase-multiplex ligation-dependent probe lification gene expression profiling assay to differentiate the main T-cell lymphoma entities and to study the heterogeneity of the "not specified" category. The test evaluates the expression of 20 genes, including 17 markers relevant to T-cell immunology and lymphoma biopathology, one Epstein-Barr virus-related transcript, and variants of
Publisher: CSIRO Publishing
Date: 1982
DOI: 10.1071/ZO9820495
Abstract: In a scanning electron microscopical study of the surface of the glans penis from some Australian rodents, it was found that most species had a long, thick structure with small dorsally projecting spines. In Pseudomys apodemoides, P. delicatulus and P. novaehollandiae the glans was smaller and thinner, with longer spines, and had a prominent bacular mound. The most ergent penes were found in Notomys alexis, N. fuscus and N. mitchelli, in which the glans was small, with very large spines, and tapered to a narrow tip. By contrast, in N. cervinus and N. longicaudatus the glans was more cylindrical and had a prominent bacular mound. The possible significance of these findings is discussed.
Publisher: Wiley
Date: 14-08-2006
Publisher: Wiley
Date: 11-1994
Abstract: Polyclonal antibodies were raised against the extracellular coats (mucoid and shell membrane) of unfertilized oocytes and early embryos of a dasyurid marsupial, the fat-tailed dunnart (Sminthopsis crassicaudata). Indirect immunofluorescence was used to test the specificity of the antibodies to the shell membrane. Streptavidin/biotin immunoperoxidase cytochemistry revealed that precursors of the tertiary egg membranes are secreted by the luminal epithelium of the ulla, isthmus (including the crypts), utero-tubal junction, and adjacent endometrial glands. Histochemistry distinguished between the sites of mucoid and shell membrane precursor secretion. The mucoid coat stained positively with Alcian blue at pH 1.0 and 2.5, with Alcian blue at pH 0.2 after performic acid oxidation, and with PAS which was amylase resistant. Some of the luminal epithelial cells of the ulla and isthmus, as well as its crypts, also stained positively by these histochemical methods but the luminal epithelium of the utero-tubal junction and endometrial glands were negative for all methods. The shell membrane did not stain with any of the above methods nor with dihydroxy-dinapthyl-disulphide (DDD) or ferric ferricyanide but it was eosinophilic and stained positively with the red cytoplasmic stain of Masson's trichrome. Therefore, it is concluded that shell membrane precursors are secreted by the luminal epithelium of the utero-tubal junction, adjacent glands, and by scattered glands in the anterior region of the uterus but not by any cell population of the oviduct.
Publisher: Bioscientifica
Date: 03-1994
Abstract: The effect of different cryopreservation methods on the development and ultrastructure of preimplantation embryos of Sminthopsis crassicaudata, a small carnivorous marsupial and member of the family Dasyuridae, was investigated. Females were primed with 1 iu pregnant mares' serum gonadotrophin to induce oestrus and ovulation. Mating generally ensued and, approximately 6 days after priming, embryos were collected and cultured in 5% CO2 in air at 35 degrees C for 18-22 h in either Dulbecco's modified Eagles medium (DMEM) with high glucose or human tubal fluid medium (HTF), both supplemented with 10% fetal calf serum. Cleavage rates were higher in DMEM than in HTF. One slow and two ultrarapid freezing methods were used. Two out of 12 (17%) embryos cleaved in culture after freezing and thawing using the slow regimen, compared with six of 16 (38%) non-frozen controls. In addition, two of 11 (18%) embryos cleaved in culture following ultrarapid freezing and thawing by one of the two methods, compared to 31 of 41 (76%) non-frozen controls. Most of the embryos appeared morphologically normal under the light microscope after freezing and thawing by the slow regimen, but considerable variation in the degree of ultrastructural damage to the cellular organelles was evident with the transmission electron microscope. The rather low rate of cleavage after freezing and thawing was probably due, at least in part, to ultrastructural damage of the cells.
Publisher: CSIRO Publishing
Date: 1992
DOI: 10.1071/RD9920145
Abstract: Sminthopsis crassicaudata is a small (approximately 16 g) polyovulatory dasyurid marsupial which has the potential to become an important model species. This study examined the use of exogenous hormone treatment to manipulate the breeding of S. crassicaudata and as a means to obtain timed developmental stages for further study. Two thirds (21/32) of the females treated with 1.0 or 5.0 I.U. of pregnant mare serum gonadotrophin (PMSG) had ovulated when the contents of their reproductive tracts were examined 5 or 6 days later. Only one of eight females treated with 0.2 I.U. PMSG had ovulated in the same period. Although a similar proportion of animals treated with 1.0 I.U. and 5.0 I.U. ovulated, the ovulation rate was significantly lower when the higher dose was administered (mean of 10.5 ovulations per female v. 3.8 ovulations per female). In addition, the ovaries of 6/8 of the animals treated with 5.0 I.U. PMSG had luteinized follicles with degenerating oocytes, evidence of over-stimulation. Follicular luteinization also occurred in 4/8 animals treated with 1 I.U. PMSG. Oocyte maturation and ovulation occurred following PMSG stimulation without injection of synthetic gonadotrophin releasing hormone (GnRH). Treatment with a 10-micrograms dose of GnRH following PMSG seemed to have no effect on the outcome. Of the females that had ovulated by Day 6, three quarters had mated and some had fertilized eggs and two-cell embryos in the oviducts and uteri. In a further series of experiments the subsequent development of embryos conceived after PMSG treatment was assessed. Two thirds of treated females mated within 7 days of treatment and 60% of these matings yielded embryos when examined 11 days after PMSG. However, full-term development was only achieved in one animal. Gonadotrophin treatment of S. crassicaudata thus may have application as a means to obtain mature or maturing oocytes, cleavage stage embryos and blastocysts, but at this stage it appears not to offer promise as a method to achieve full-term development.
Publisher: Bioscientifica
Date: 04-2007
DOI: 10.1530/REP-06-0043
Abstract: In mammals, before fertilization can occur, sperm have to bind to, and penetrate, the zona pellucida (ZP). In the laboratory mouse, which has been used as a model system for fertilization studies, sperm–ZP binding has been found to be mediated by a region at the carboxy terminal, encoded by exon 7 of the Zp3 gene. This region shows considerable interspecific sequence ersity with some evidence of adaptive evolution in mammals, suggesting that it may contribute to species-specific sperm–ZP binding. However, in a previous study of sequence ersity of ZP3 of three species of Australian murine rodents, we found an identical protein sequence of the region encoded by exon 7. Here, we expand this earlier study to determine the sequence ersity of this region in 68 out of the 130 species of Australasian murine rodents. Maximum likelihood analyses, using representatives of both New Guinean and Australian taxa, provide evidence of positive selection at three codons adjacent to, or within, the putative combining-site for sperm of ZP3, but this was not evident when the analysis was restricted to the Australian taxa. The latter group showed low levels of both intra- and inter-generic sequence ergences in the region encoded by exon 7 of Zp3, with little evidence that this region contributes to species specificity of sperm–ZP binding. These findings suggest that the selective forces acting on the Zp3 exon 7 region during the evolution of the Australasian murine rodents have been variable, and that positive selection has only occurred in a few lineages.
Publisher: CSIRO Publishing
Date: 1995
DOI: 10.1071/ZO9950017
Abstract: Observations on sperm morphology from most species of murid rodents from New Guinea and the Solomon Islands, based on light microscopy, are presented. Transmission electron microscopy of spermatozoa for three species in two genera are also given. All Rattus species, Melomys lanosus, M. rattoides, Lorentzimys nouhuysi and Coccymys ruemmleri have sickle-shaped sperm heads and long sperm tails. In contrast, most of the other species have sperm with a broader lateral face and three ventral processes. These processes vary somewhat in size and shape, and in two Pogonomys and one Chiruromys species there is an extension of the nucleus into the most caudal of the three processes. Species of Anisomys and Hyomys have a sperm head with a broad lateral face but with only a single apical process. Abeomelomys sevia and Solomys salebrosus each have a distinct sperm head morphology unlike that of any other Australian murid the latter species also has an extremely short sperm tail. Taxonomic and phylogenetic inferences are drawn from these data. Some of the phylogenetic conclusions are markedly ergent from traditional views, which are based on craniodental anatomy.
Publisher: S. Karger AG
Date: 1985
DOI: 10.1159/000145959
Abstract: The large ventral prostate of the hopping mouse has abundant secretory units whose epithelial cells vary in height and which often have nuclei in the apical region of the cell. TEM observations indicated two epithelial cell types in which some unusual features occurred. Type A cells had granular endoplasmetic reticulum (GER) whose membranes often formed intracytoplasmic confronting cisternae. Type B cells had more fragmented and vesiculated GER with sparse ribosomes and less frequently also intracytoplasmic confronting cisternae. In the latter cells, two types of granules were found, one of which was derived from the Golgi and the other possibly directly from the GER. Type A cells only had one type of granule present. A highly convoluted membrane was also found at the basal region in many of the cells. The significance of these unusual ultrastructural features has yet to be ascertained.
Publisher: CSIRO Publishing
Date: 2011
DOI: 10.1071/ZO11051
Abstract: In most mammalian species, the temperature of scrotal testes is several degrees lower than that of core body temperature due to the presence of a counter-current heat exchange between the coiled testicular artery and the p iniform plexus of veins. Here we ask: have hopping mice developed a highly efficient cooling mechanism within their scrotal sac and/or germ cell resistance to high environmental temperatures? To investigate this, adult male sexually mature Notomys alexis were used to determine: (1) the temperature of the testes (2) the extent of coiling of the testicular artery (3) the effect of artificially induced cryptorchidism on spermatogenesis up to three weeks after surgery and (4) the effect of whole body heat exposure of 37−38°C for 8 h per day for three consecutive days on germ cell apoptosis. The results showed that in hopping mice the testicular artery, unlike that in most other mammalian species, is not coiled although the temperature in the scrotum was found to be ~2°C lower than that of the abdomen. In cryptorchid males, 21 days after surgery, testes weights were reduced in three of five in iduals but there was no statistically significant decrease after 16 h exposure to whole body heat (P = 0.07). Nevertheless, some impairment of spermatogenesis was evident in both the cryptorchid testes and in the testes after whole body heating. These results show that in hopping mice developing male germ cells are susceptible to degeneration when testes are exposed to high environmental temperatures. Thus adaptations of Notomys alexis to the arid zone have not involved any special adaptations for male germ cell survival in a hot environment. Behavioural adaptations may play a pivotal role in maintaining maximal male fertility in such extreme environmental conditions.
Publisher: Wiley
Date: 06-10-2010
DOI: 10.1002/JMOR.10889
Abstract: The morphology of the spermatozoon of representative species of the subfamily Nesomyinae (Muroidea: Nesomyidae), a monophyletic group of rodents endemic to Madagascar, was examined by light and electron microscopy to determine the sperm head shape and tail length across the species. Marked interspecific differences were found to occur in both the form of the sperm head and length of the tail. The species that possess a sperm head with an apical hook, which largely contains acrosomal material, generally displayed longer sperm tails, and a species with a spatulate sperm head had the shortest tail. The association between sperm head shape and tail length mirrors that previously found in Eurasian and Australasian murine rodents. Thus, the repeated association between sperm head shape and tail length across these groups of muroid rodents clearly indicates a functional relationship between these two features. A comparison of sperm morphology of the nesomyines to that of related muroid rodents on the mainland of Africa suggests that the possession of an apical hook is the ancestral condition.
Publisher: Informa UK Limited
Date: 1995
DOI: 10.3109/10520299509108335
Abstract: Fluorescence microscopy of caudal epididymal spermatozoa stained with 3, 3' dihexyloxacarbocyanine iodide (DiOC6(3)) showed intense fluorescence along the concave surface of the apical hook of spermatozoa of Rattus species and along the upper concave margin of the sperm head in Mus musculus. In the spermatozoa of Hydromys chrysogaster, Melomys cervinipes, and Pseudomys australis, the two ventral processes also fluoresced brightly. In P. australis, fluorescence in the apical hook of sperm heads was largely localized to its upper and lower surfaces. The sperm of N. alexis did not show consistent positive fluorescence. The localization of fluorescence in these spermatozoa after staining with DiOC6(3) was mainly restricted to regions where a large accumulation of perinuclear theca material lies beneath the plasmalemma. The reason for this remains to be determined, but DiOC6(3) may be useful for quickly demonstrating areas of abundant perinuclear thecal material in sperm heads of eutherian mammals by light microscopy.
Publisher: CSIRO Publishing
Date: 1976
DOI: 10.1071/ZO9760533
Abstract: The effect of age on the female reproductive system of N. alexis was investigated in the following age groups: (1) 2.5-6 months (2) 1-2 years (3) years old. Oestrous cycle length was slightly reduced in group 2 females relative to group 1, but most group 3 females showed either constant dioestrus or constant oestrus. Body, ovarian and uterine weights all tended to increase with age, and Graafian follicles and corpora lutea were present in females in all groups although the latter were significantly fewer in group 3. Cytology of uterine epithelial cells of females in dioestrus indicated that numbers of microvilli in old animals were somewhat variable but generally decreased, some cells appearing almost devoid of them, whereas numbers of secondary lysosomes and multi-vesicular bodies tended to increase. The effect of these differences on possible infertility have, however, yet to be proved.
Publisher: CSIRO Publishing
Date: 2006
DOI: 10.1071/RD05047
Abstract: The effect of the exogenous administration of porcine follicle-stimulating hormone (pFSH) and pregnant mare serum gonadotrophin (PMSG) on ovarian follicular development and oocyte maturation in the southern hairy nosed wombat Lasiorhinus latifrons was investigated. Three experimental groups were administered pFSH at various doses and for different treatment lengths, followed by 25 mg porcine luteinising hormone (pLH) 12 h after the last dose of pFSH. Another group was given PMSG followed 72 h later by 25 mg pLH. Animals were killed 24 h after pLH. The left ovary was fixed for histology and the morphology of the antral follicles was determined, whereas follicular oocytes in the right ovary were aspirated, fixed, stained with 4′,6′-diamidino-2-phenylindole, and viewed for nuclear maturation. There was no significant difference in the mean number of ovarian follicles mm, or in the size class of follicles assessed between control and experimental groups. However, a trend was observed suggesting a possible increase in follicles .0 mm in experimental groups compared with control animals. In all females administered exogenous porcine gonadotrophins, but not controls, some of the mural granulosa cells of large tertiary antral follicles had markedly enlarged nuclei (approximately 14 µm in diameter). All oocytes from the control group remained at the germinal vesicle stage, whereas approximately 40% of oocytes retrieved from the pFSH groups and 82.4% retrieved from the PMSG-primed animals had undergone germinal vesicle break down, with a small number reaching meiosis II. The present study shows that exogenous administration of either pFSH or PMSG to hairy nosed wombats can induce follicular growth and oocyte maturation. Such findings could be useful in the development of reproductive technology in this species.
Publisher: Bioscientifica
Date: 11-1975
Abstract: Australian hopping mice (Notomy alexis) were subjected to short or long photoperiods, different social environments and/or water deprivation. The age at which vaginal opening and first oestrus occurred was delayed by short photoperiods and by the absence of male proximity. Water deprivation prevented normal maturation. The normal 7 to 8 day oestrous cycle was prolonged by short photoperiods or water deprivation. Animals deprived of water had lighter body, ovarian and uterine weights, and follicular growth seemed to be impaired. No differences in organ weights were found between animals in the two photoperiods. The significance of the findings is discussed.
Publisher: CSIRO Publishing
Date: 2017
DOI: 10.1071/RD16455
Abstract: In eutherian mammals, before fertilisation can occur the spermatozoon has to bind to, and penetrate, the egg coat, the zona pellucida (ZP). In the laboratory mouse there is good evidence that the primary sperm-binding site is a protein region encoded by Exon 7 of the ZP3 gene and it has been proposed that binding is species specific and evolves by sexual selection. In the present study we investigate these hypotheses by comparing Exon 6 and 7 sequences of ZP3 in 28 species of murine rodents of eight different isions from Asia, Africa and Australasia, in which a erse array of sperm morphologies occurs. We found considerable nucleotide (and corresponding amino acid) sequence ergence in Exon 7, but not in Exon 6, across these species, with evidence for positive selection at five codon positions. This molecular ergence does not appear to be due to reinforcement to reduce hybridisation, nor does it correlate with ergence in sperm head morphology or tail length, thus it is unlikely to be driven by inter-male sperm competition. Other forms of post-copulatory sexual selection therefore appear to have resulted in the molecular ergence of this region of ZP3 in this highly speciose group of mammals.
Publisher: Wiley
Date: 05-1989
Abstract: A study of spermatozoa in the isthmus of the oviduct and of the surrounding epithelial cells in the dasyurid marsupial, Sminthopsis crassicaudata, was carried out. At least 10% of the ejaculated spermatozoa probably populate the isthmus region, where many come to reside in crypts until around the time of ovulation. Ultrastructural observations of spermatozoa in this region indicated that they had intact acrosomes and were identical in their morphology with those in the cauda epididymidis. After ovulation spermatozoa rapidly disappeared, some of which may be phagocytosed by the cells lining the crypts. These epithelial cells were also found to have many large, electron-dense granules at the time of sperm storage, but the contents did not appear to be released until the zygotes passed along the tract. The secretory activity of these cells may thus relate more to the production of the shell membrane that comes to surround the zygote than to the cells performing a nutritive or protective function for the spermatozoa during their period of storage within the female reproductive tract.
Publisher: Public Library of Science (PLoS)
Date: 24-01-2007
Publisher: Wiley
Date: 1984
Publisher: Wiley
Date: 05-1990
Abstract: This light and transmission electron microscopical study shows that the first polar body is given off before ovulation and that part of its cell membrane and that of the surrounding oocyte have long microvilli at the time of its ejection. Several layers of cumulus cells initially surround the secondary oocyte and first polar body, but the ovulated oocytes in the oviducts in the process of being fertilized do not have cumulus cells around them. Partly expelled second polar bodies occur in the oviduct they are elongated structures that lack organelles and have electron-dense nuclei. A small fertilization cone appears to form around the sperm tail at the time of sperm entry into the egg and an incorporation cone develops around the sperm head in the egg cytoplasm. In three fertilized eggs a small hole was seen in the zona, which was presumably formed by the spermatozoon during penetration. Cortical granules, present in ovarian oocytes, are not seen in fertilized tubal or uterine eggs release of their contents probably reduces the chances of polyspermy, although at least one polyspermic fertilized egg was seen and several other fertilized eggs had spermatozoa within the zona pellucida. In the zygote the pronuclei come to lie close together, but there was no evidence of fusion. A "yolk mass," which becomes eccentric before ovulation, is extruded by the time the two-cell embryos are formed, but many vacuoles remain in the non-yolky pole of the egg. A shell membrane of variable thickness is present around all uterine eggs but its origin remains undetermined.
Location: United Kingdom of Great Britain and Northern Ireland
No related grants have been discovered for William Breed.