Sperm design varies enormously across species and sperm competition is thought to be a major factor influencing this variation. However, the functional significance of many traits still poorly understood. The most murid rodents are characterised by an apical hook head that markedly in extent species. In European woodmouse Apodemus sylvaticus (Muridae), highly reflected used form groups, or "trains," which exhibited increased swimming velocity thrusting force compared individual sperm.Here we...

Phylogeographic studies of continental clades, especially when combined with palaeoclimate modelling, provide powerful insight into how environment drives speciation across climatic contexts. Australia, a continent characterized by disparate modern biomes and dynamic climate change, provides diverse opportunity to reconstruct the impact past present environments on diversification. Here, we use genomic-scale data (1310 exons whole mitogenomes from 111 samples) investigate Pleistocene...

The relationships among testes mass, sperm size (as indicated by tail length), and body mass of Old World rats mice were investigated. A near isometric relationship between was found but not size. In a few lineages, deviated considerably from the regression line with relatively very small occurring in Bunomys fratrorum, Bandicota indica, B. savilei Asia, Aethomys ineptus Africa, some Pseudomys, all Notomys Australia. By contrast, large occurred Apodemus, Berylmys, Maxomys bartelsii Pogonomys...

Abstract The murine rodents are the most speciose subfamily of mammals. Here morphology spermatozoon, as determined by scanning and transmission electron microscopy representative species from four Eurasian clades, is described. Much interspecific variability in all components spermatozoon was found to occur, although have a bilaterally flattened sperm head with single apical hook variable length orientation. Ultrastructural observations indicate that this invariably contains nuclear...

It has been shown that photoperiod affects the reproductive development of vole, Microtus agrestis, ovaries and uteri weighing more in laboratory-simulated summer than winter (Clarke & Kennedy, 1967). Photoperiod a similar effect on ovarian function M. arvalis (Lecyk, 1962; Thibault, Courot, Martinet, Mauléon, du Mesnil Buisson, Ortavant, Pelletier Signoret, 1966). In order to define accurately influence light sexual six different photoperiods onset puberty activity virgin voles after 8...

Context This paper explores the morphology of spermatozoa in Australian hydromyine rodents, specifically focusing on plains mouse (Pseudomys australis), and examines interactions between sperm eggs at time fertilisation. Aims The aim this study is to provide an overview comparing its across different species investigate gametes fertilisation mouse. Methods We summarise head rodents six divisions, with emphasis structure zona pellucida during Key results Most including mouse, exhibit a highly...

The fat-tailed dunnart, Sminthopsis crassicaudata, is a small insectivorous dasyurid (adult weight about 16 g) widely distributed in Australia. A laboratory colony of this marsupial, which has been built up over many years, providing material for studies reproductive biology and genetics. In the area biology, we have found marked disparity age maturation between two sexes, are currently studying certain aspects spermatogenesis, sperm transport, fertilisation early embryonic development....

Actin was localized in the sperm head of plains mouse, Pseudomys australis, using NBD-phallacidin, a fluorescent-labeled phallotoxin. It found to be present two ventral hooks from testis, epididymis, and vas deferens. Faint fluorescence observed other regions head, whereas autofluorescence occurred midpiece tail some preparations. The material also birefringent, which is consistent with it showing preferential orientation.

The disposition of spermatozoa in the female tract dasyurid marsupial, Sminthopsis crassicaudata, was examined before and after ovulation, by transillumination using differential interference optics. At 6–30 h mating females with maturing follicles, were restricted to special storage crypts that define isthmus Fallopian tube. These mostly immotile spear shaped, except for 50–200 vanguard within anterior T shaped due a rotation head on tail. After ovulation arrival eggs narrow upper ovarian...

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 testes exhibited bright fluorescence over entire head; those caput epididymides generally fluoresced more brightly post-acrosomal region; and spermatozoa caudae less brightly, with foci sperm head which were lost after extraction Triton X-100 hence appeared be membrane-associated. Treatment cauda sodium dodecyl sulfate resulted a...

Abstract A study of spermatozoa in the isthmus oviduct and surrounding epithelial cells dasyurid marsupial, Sminthopsis crassicaudata , was carried out. At least 10% ejaculated probably populate region, where many come to reside crypts until around time ovulation. Ultrastructural observations this region indicated that they had intact acrosomes were identical their morphology with those cauda epididymidis. After ovulation rapidly disappeared, some which may be phagocytosed by lining crypts....

Abstract In the rodent superfamily Muroidea, a model for evolution of sperm form has been proposed in which it is suggested that hook‐shaped head and long tail evolved from more simple, nonhooked short several different subfamilies. To test this shape head, with particular emphasis on its apical region, length were matched to recent phylogeny based nucleotide sequence protein‐coding nuclear genes 3 families 10 subfamilies muroid rodents. Data two other myomorph superfamilies, Dipodoidea...

The wild and captive koala population of the Mt Lofty Ranges in South Australia has a high level renal dysfunction which crystals consistent with calcium oxalate have been observed kidneys. This study aimed to describe pathological features disease this population, confirm composition as oxalate, determine whether any age or sex predispositions exist for disease. A total 51 koalas (28 rescues, 23 captive) were examined at necropsy, 28 (55%) found gross and/or histological evidence nephrosis....

Lactation lasts for about 14 days in the field vole.Early lactation corpora lutea were large although some signs of degeneration present; by Day 13 none could be recognized.Graafian follicles present throughout period but slightly reduced size during mid-lactation.Vaginal smear patterns varied considerably between individuals nucleated epithelial cells usually predominated.Mating tests carried out Days 2 and lactation.81% proved successful; coitus occurred on all days.59% matings resulted...

Abstract This light and transmission electron microscopical study shows that the first polar body is given off before ovulation part of its cell membrane surrounding oocyte have long microvilli at time ejection. Several layers cumulus cells initially surround secondary body, but ovulated oocytes in oviducts process being fertilized do not around them. Partly expelled second bodies occur oviduct; they are elongated structures lack organelles electron‐dense nuclei. A small fertilization cone...

Abstract This scanning and transmission electron microscopical study has been performed to determine the extent of development subacrosomal space in sperm head various members subfamily, Hydromyinae, which is a diverse group murid rodents occurring habitats Australia. Sperm all species from three tribes Hydromyini, Uromyini, Conilurini investigated this had with hooks although their absolute relative lengths varied markedly. The top hook was similar structure that present many other typical...