Sample records for voles arborimus longicaudus

  1. Field guide to red tree vole nests (United States)

    Damon B. Lesmeister; James K. Swingle


    Surveys for red tree vole (Arborimus longicaudus) nests require tree climbing because the species is a highly specialized arboreal rodent that live in the tree canopy of coniferous forests in western Oregon and northwestern California. Tree voles are associated with old coniferous forest (≥80 years old) that are structurally complex, but are often...

  2. Taxonomic relationships among Phenacomys voles as inferred by cytochrome b (United States)

    Bellinger, M.R.; Haig, S.M.; Forsman, E.D.; Mullins, T.D.


    Taxonomic relationships among red tree voles (Phenacomys longicaudus longicaudus, P. l. silvicola), the Sonoma tree vole (P. pomo), the white-footed vole (P. albipes), and the heather vole (P. intermedius) were examined using 664 base pairs of the mitochondrial cytochrome b gene. Results indicate specific differences among red tree voles, Sonoma tree voles, white-footed voles, and heather voles, but no clear difference between the 2 Oregon subspecies of red tree voles (P. l. longicaudus and P. l. silvicola). Our data further indicated a close relationship between tree voles and albipes, validating inclusion of albipes in the subgenus Arborimus. These 3 congeners shared a closer relationship to P. intermedius than to other arvicolids. A moderate association between porno and albipes was indicated by maximum parsimony and neighbor-joining phylogenetic analyses. Molecular clock estimates suggest a Pleistocene radiation of the Arborimus clade, which is concordant with pulses of diversification observed in other murid rodents. The generic rank of Arborimus is subject to interpretation of data.

  3. Bank voles (Myodes glareolus) and house mice (Mus musculus musculus; M. m. domesticus) in Europe are each parasitized by their own distinct species of Aspiculuris (Nematoda, Oxyurida). (United States)

    Behnke, J M; Stewart, A; Bajer, A; Grzybek, M; Harris, P D; Lowe, A; Ribas, A; Smales, L; Vandegrift, K J


    The molecular phylogeny and morphology of the oxyuroid nematode genus Aspiculuris from voles and house mice has been examined. Worms collected from Myodes glareolus in Poland, Eire and the UK are identified as Aspiculuris tianjinensis, previously known only from China, while worms from Mus musculus from a range of locations in Europe and from laboratory mice, all conformed to the description of Aspiculuris tetraptera. Worms from voles and house mice are not closely related and are not derived from each other, with A. tianjinensis being most closely related to Aspiculuris dinniki from snow voles and to an isolate from Microtus longicaudus in the Nearctic. Both A. tianjinensis and A. tetraptera appear to represent recent radiations within their host groups; in voles, this radiation cannot be more than 2 million years old, while in commensal house mice it is likely to be less than 10,000 years old. The potential of Aspiculuris spp. as markers of host evolution is highlighted.

  4. Amplified Fragment Length Polymorphism (AFLP) data obtained for 34 Microtus longicaudus individuals at 91 loci (United States)

    U.S. Geological Survey, Department of the Interior — Prior to removal of pest species from an area, resource managers must determine if re-immigration from another population is possible. Voles inhabiting Saddle Rock...

  5. How expensive is vole damage?


    Walther, B; Fülling, O.; Malevez, J.; Pelz, H.-J.


    Vole species, especially Arvicola terrestris and Microtus arvalis cause significant economical damage in organic pomiculture by gnawing the root system of trees. The importance of voles as pest organisms is well known. Nevertheless, the estimation of financial loss caused by voles is difficult for German fruit growers. We conducted a survey among organic fruit growers to get data on kind and amount of annual damage. Using the available publications and official statistics we calculated econom...

  6. Genetics of Aggression in Voles


    Gobrogge, Kyle L.; Wang, Zuoxin


    Prairie voles (Microtus ochrogaster) are socially monogamous rodents that form pair bonds—a behavior composed of several social interactions including attachment with a familiar mate and aggression toward conspecific strangers. Therefore, this species has provided an excellent opportunity for the study of pair bonding behavior and its underlying neural mechanisms. In this chapter, we discuss the utility of this unique animal model in the study of aggression and review recent findings illustra...

  7. Parasite diversity at the Holarctic nexus: species of Arostrilepis (Eucestoda: Hymenolepididae) in voles and lemmings (Cricetidae: Arvicolinae) from greater Beringia. (United States)

    Makarikov, Arseny A; Galbreath, Kurt E; Hoberg, Eric P


    Previously unrecognized species of hymenolepidid cestodes attributable to Arostrilepis Mas-Coma & Tenora, 1997 in arvicoline rodents from the greater Beringian region and western North America are described. Discovery and characterization of these tapeworms contributes to the recognition of a complex of cryptic species distributed across the Holarctic region. Three species are proposed: Arostrilepis gulyaevi sp. n. is named for cestodes in Myodes rufocanus from the Republic of Buryatia, southeastern Siberia and from the Khabarovskiy Kray, Chukotka Autonomous Okrug, and Magadanskaya Oblast', Russian Far East (western Beringia); A. cooki sp. n. is named for cestodes in Myodes gapperi from British Columbia, Canada and Montana, USA; and A. rauschorum sp. n. is named for cestodes in Microtus oeconomus, M. longicaudus, M. pennsylvanicus and M. xanthognathus from the Brooks Range, Seward Peninsula, north-central interior, and Arctic coastal plains of Alaska (eastern Beringia) and Montana, USA. Consistent with recent studies defining diversity in the genus, the form, size, and spination (pattern, shape and size) of the cirrus are diagnostic; species are further distinguished by the relative position and length of the cirrus sac, and arrangement of the testes. Assessment of genetic data from the cytochrome b gene of mitochondrial DNA complements differentiation of this complex based on morphological attributes and confirms known species diversity within the genus. New data for geographical distribution and host specificity of known Arostrilepis spp. indicate that 3 of 12 recognized species have Holarctic distributions extending across Beringia. These include Arostrilepis beringiensis (Kontrimavichus & Smirnova, 1991) in lemmings (species of Lemmus and Synaptomys), A. cf. janickii Makarikov & Kontrimavichus, 2011 in root voles (M. oeconomus) MAKARIKOV ET AL. 402 · Zootaxa 3608 (6) © 2013 Magnolia Press and A. macrocirrosa Makarikov, Gulyaev & Kontrimavichus, 2011 in red

  8. Diabetes in Danish Bank Voles (M. glareolus)

    DEFF Research Database (Denmark)

    Schønecker, Bryan; Freimanis, Tonny; Sørensen, Irene Vejgaard


    , specificity, positive predictive value, and negative predictive value, equalled 69%, 97%, 89%, and 89%, respectively. The relatively long survival of Danish PD bank voles suggests potentials for this model in future studies of the long-term complications of diabetes, of which some observations are mentioned......Previous studies have concluded that the development of polydipsia (PD, a daily water intake ≥21 ml) among captive Danish bank voles, is associated with the development of a type 1 diabetes (T1D), based on findings of hyperglycaemia, glucosuria, ketonuria/-emia, lipemia, destroyed beta cells...... as a practical and non-invasive tool to screen for voles with a high probability of hypeglycaemia. In addition, we discuss regional differences related to the development of diabetes in Scandinavian bank voles and the relevance of the Ljungan virus as proposed etiological agent. We found that median survival...

  9. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie (United States)

    Carlson, CM; Schneider, Jay R.; Pedersen, Janice C.; Heisey, Dennis M.; Johnson, Christopher J.


    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  10. Experimental infection of meadow voles (Microtus pennsylvanicus) with sheep scrapie. (United States)

    Carlson, Christina M; Schneider, Jay R; Pedersen, Joel A; Heisey, Dennis M; Johnson, Christopher J


    Meadow voles (Microtus pennsylvanicus) are permissive to chronic wasting disease (CWD) infection, but their susceptibility to other transmissible spongiform encephalopathies (TSEs) is poorly characterized. In this initial study, we intracerebrally challenged 6 meadow voles with 2 isolates of sheep scrapie. Three meadow voles acquired a TSE after the scrapie challenge and an extended incubation period. The glycoform profile of proteinase K-resistant prion protein (PrP(res)) in scrapie-sick voles remained similar to the sheep inocula, but differed from that of voles clinically affected by CWD. Vacuolization patterns and disease-associated prion protein (PrP(Sc)) deposition were generally similar in all scrapie-affected voles, except in the hippocampus, where PrP(Sc) staining varied markedly among the animals. Our results demonstrate that meadow voles can acquire a TSE after intracerebral scrapie challenge and that this species could therefore prove useful for characterizing scrapie isolates.

  11. Puumala Virus in Bank Voles, Lithuania (United States)

    Straková, Petra; Jagdmann, Sandra; Balčiauskas, Linas; Balčiauskienė, Laima; Drewes, Stephan


    Little is known about the presence of human pathogenic Puumala virus (PUUV) in Lithuania. We detected this virus in bank voles (Myodes glareolus) in a region of this country in which previously PUUV-seropositive humans were identified. Our results are consistent with heterogeneous distributions of PUUV in other countries in Europe. PMID:27983939

  12. Vole and lemming activity observed from space (United States)

    Olofsson, Johan; Tømmervik, Hans; Callaghan, Terry V.


    Predicting the impacts of present global warming requires an understanding of the factors controlling plant biomass and production. The extent to which they are controlled by bottom-up drivers such as climate, nutrient and water availability, and by top-down drivers such as herbivory and diseases in terrestrial systems is still under debate. By annually recording plant biomass and community composition in grazed control plots and in herbivore-free exclosures, at 12 sites in a subArctic ecosystem, we were able to show that the regular interannual density fluctuations of voles and lemmings drive synchronous interannual fluctuations in the biomass of field-layer vegetation. Plant biomass in the field layer was between 12 and 24% lower the year after a vole peak than the year before, and the combined vole and lemming peaks are visible as a reduced normalized difference vegetation index in satellite images over a 770km2 area in the following year, despite the wide range of abiotic, biotic and anthropogenic forces that influence the vegetation. This strongly suggests that the cascading effect of rodents for the function and diversity of tundra plant communities needs to be included in our scenarios of how these ecosystems will respond to environmental changes.

  13. Are water vole resistant to anticoagulant rodenticides following field treatments? (United States)

    Vein, Julie; Grandemange, Agnès; Cosson, Jean-François; Benoit, Etienne; Berny, Philippe J


    The anti-vitamin Ks (AVKs) are widely used to control rodent populations. They inhibit Vitamin K regeneration by the Vitamin K Epoxide Reductase (VKOR) and cause a fatal hemorrhagic syndrome. Because of repeated use, some populations of commensal rodents have expressed resistance to these compounds. In Franche-Comté (France), the water vole exhibits cyclic population outbreaks. A second generation AVK, bromadiolone, has been used for the last 20 years to control vole populations. The aim of this study is to determine whether these repeated treatments could have led to the development of resistance to AVKs in water vole populations. We conducted enzymatic and genetic studies on water voles trapped in treated and non treated plot. The results indicate that voles from the most heavily treated area exhibit enzymatic changes in VKOR activity hence arguing for resistance to AVKs and that an intronic haplotype on the vkorc1 gene seems to be associated with these enzymatic changes.

  14. Identifying shared genetic structure patterns among Pacific Northwest forest taxa: insights from use of visualization tools and computer simulations.

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    Mark P Miller

    Full Text Available BACKGROUND: Identifying causal relationships in phylogeographic and landscape genetic investigations is notoriously difficult, but can be facilitated by use of multispecies comparisons. METHODOLOGY/PRINCIPAL FINDINGS: We used data visualizations to identify common spatial patterns within single lineages of four taxa inhabiting Pacific Northwest forests (northern spotted owl: Strix occidentalis caurina; red tree vole: Arborimus longicaudus; southern torrent salamander: Rhyacotriton variegatus; and western white pine: Pinus monticola. Visualizations suggested that, despite occupying the same geographical region and habitats, species responded differently to prevailing historical processes. S. o. caurina and P. monticola demonstrated directional patterns of spatial genetic structure where genetic distances and diversity were greater in southern versus northern locales. A. longicaudus and R. variegatus displayed opposite patterns where genetic distances were greater in northern versus southern regions. Statistical analyses of directional patterns subsequently confirmed observations from visualizations. Based upon regional climatological history, we hypothesized that observed latitudinal patterns may have been produced by range expansions. Subsequent computer simulations confirmed that directional patterns can be produced by expansion events. CONCLUSIONS/SIGNIFICANCE: We discuss phylogeographic hypotheses regarding historical processes that may have produced observed patterns. Inferential methods used here may become increasingly powerful as detailed simulations of organisms and historical scenarios become plausible. We further suggest that inter-specific comparisons of historical patterns take place prior to drawing conclusions regarding effects of current anthropogenic change within landscapes.

  15. Chromosomal evolution of Arvicolinae (Cricetidae, Rodentia). I. The genome homology of tundra vole, field vole, mouse and golden hamster revealed by comparative chromosome painting. (United States)

    Sitnikova, Natalia A; Romanenko, Svetlana A; O'Brien, Patricia C M; Perelman, Polina L; Fu, Beiyuan; Rubtsova, Nadezhda V; Serdukova, Natalya A; Golenishchev, Feodor N; Trifonov, Vladimir A; Ferguson-Smith, Malcolm A; Yang, Fengtang; Graphodatsky, Alexander S


    Cross-species chromosome painting has become the mainstay of comparative cytogenetic and chromosome evolution studies. Here we have made a set of chromosomal painting probes for the field vole (Microtus agrestis) by DOP-PCR amplification of flow-sorted chromosomes. Together with painting probes of golden hamster (Mesocricetus auratus) and mouse (Mus musculus), the field vole probes have been hybridized onto the metaphases of the tundra vole (Microtus oeconomus). A comparative chromosome map between these two voles, golden hamster and mouse has been established based on the results of cross-species chromosome painting and G-banding comparisons. The sets of paints from the field vole, golden hamster and mouse identified a total of 27, 40 and 47 homologous autosomal regions, respectively, in the genome of tundra vole; 16, 41 and 51 fusion/fission rearrangements differentiate the karyotype of the tundra vole from the karyotypes of the field vole, golden hamster and mouse, respectively.

  16. Prairie forb response to timing of vole herbivory. (United States)

    Sullivan, Amy T; Howe, Henry F


    The timing of herbivory can be an important factor in the strength and direction of plant response to herbivore damage. To determine the effect of vole herbivory timing within a growing season on tallgrass prairie forbs, we used individual plant enclosures to limit vole access to three species, Desmanthus illinoensis, Echinacea purpurea, and Heliopsis helianthoides, in an experimental restoration in northern Illinois, USA. As part of a long-term experiment, we implemented five vole access treatments in 2003: (1) vole access for the entire growing season, (2) early-season access, (3) mid-season access, (4) late-season access, and (5) no vole access. We protected all plants from herbivory in the following growing season (2004) to test whether the effects of herbivory in one growing season carried over to the next. We also tested how restoration planting design, including seeding time (June or December) and density (35 or 350 seeds/m2 of each species) affected patterns of herbivory and plant recovery. Vole access for the entire growing season was most detrimental for the growth and reproduction of all three species. In contrast, vole access for a portion of the growing season had different effects on the three species: Desmanthus growth and reproduction was negatively affected by early-season access, Echinacea reproductive output was reduced by late-season access, and Heliopsis was not affected by early-, mid-, or late-season vole access. Negative effects of continual vole access carried over to the following growing season for Desmanthus and Heliopsis, but not for Echinacea. Effects of herbivory did not carry over to the next season for Echinacea and Heliopsis when plants were accessible to voles for only part of the growing season. In contrast, Desmanthus plants exposed to early-season herbivory in one year continued to produce fewer seeds per plant after being protected from vole herbivory for a growing season. Planting density and planting season had mixed effects

  17. Stimulation of serotonin (5-HT) activity reduces spontaneous stereotypies in female but not in male bank voles (Clethrionomys glareolus) Stereotyping female voles as a new animal model for human anxiety and mood disorders?

    DEFF Research Database (Denmark)

    Schønecker, Bryan; Heller, Knud Erik


    Bank voles, Stereotypies, Sex differences, Clozapine, Citalopram, Animal model, Anxiety, Mood disorders......Bank voles, Stereotypies, Sex differences, Clozapine, Citalopram, Animal model, Anxiety, Mood disorders...

  18. Silicon-based plant defences, tooth wear and voles. (United States)

    Calandra, Ivan; Zub, Karol; Szafrańska, Paulina A; Zalewski, Andrzej; Merceron, Gildas


    Plant-herbivore interactions are hypothesized to drive vole population cycles through the grazing-induced production of phytoliths in leaves. Phytoliths act as mechanical defences because they deter herbivory and lower growth rates in mammals. However, how phytoliths impair herbivore performance is still unknown. Here, we tested whether the amount of phytoliths changes tooth wear patterns. If confirmed, abrasion from phytoliths could play a role in population crashes. We applied dental microwear texture analysis (DMTA) to laboratory and wild voles. Lab voles were fed two pelleted diets with differing amounts of silicon, which produced similar dental textures. This was most probably due to the loss of food mechanical properties through pelletization and/or the small difference in silicon concentration between diets. Wild voles were trapped in Poland during spring and summer, and every year across a population cycle. In spring, voles feed on silica-rich monocotyledons, while in the summer they also include silica-depleted dicotyledons. This was reflected in the results; the amount of silica therefore leaves a traceable record in the dental microwear texture of voles. Furthermore, voles from different phases of population cycles have different microwear textures. We tentatively propose that these differences result from grazing-induced phytolith concentrations. We hypothesize that the high amount of phytoliths in response to intense grazing in peak years may result in malocclusion and other dental abnormalities, which would explain how these silicon-based plant defences help provoke population crashes. DMTA could then be used to reconstruct vole population dynamics using teeth from pellets or palaeontological material. © 2016. Published by The Company of Biologists Ltd.

  19. Lichen compounds restrain lichen feeding by bank voles (Myodes glareolus). (United States)

    Nybakken, Line; Helmersen, Anne-Marit; Gauslaa, Yngvar; Selås, Vidar


    Some lichen compounds are known to deter feeding by invertebrate herbivores. We attempted to quantify the deterring efficiency of lichen compounds against a generalist vertebrate, the bank vole (Myodes glareolus). In two separate experiments, caged bank voles had the choice to feed on lichens with natural or reduced concentrations of secondary compounds. We rinsed air-dry intact lichens in 100% acetone to remove extracellular compounds non-destructively. In the first experiment, pairs of control and rinsed lichen thalli were hydrated and offered to the bank voles. Because the lichens desiccated fast, we ran a second experiment with pairs of ground control and compound-deficient thalli, each mixed with water to porridge. Eight and six lichen species were tested in the first and second experiment, respectively. In the first, bank voles preferred compound-deficient thalli of Cladonia stellaris and Lobaria pulmonaria, but did not discriminate between the other thallus pairs. This was likely a result of deterring levels of usnic and stictic acid in the control thalli. When lichens were served as porridge, significant preference was found for acetone-rinsed pieces of Cladonia arbuscula, C. rangiferina, Platismatia glauca, and Evernia prunastri. The increased preference was caused mainly by lower consumption of control thalli. Grinding and mixing of thallus structures prevented bank voles from selecting thallus parts with lower concentration of secondary compounds and/or strengthened their deterring capacity. We conclude that some lichen secondary compounds deter feeding by bank voles.

  20. Kinship, dispersal and hantavirus transmission in bank and common voles. (United States)

    Deter, J; Chaval, Y; Galan, M; Gauffre, B; Morand, S; Henttonen, H; Laakkonen, J; Voutilainen, L; Charbonnel, N; Cosson, J-F


    Hantaviruses are among the main emerging infectious agents in Europe. Their mode of transmission in natura is still not well known. In particular, social features and behaviours could be crucial for understanding the persistence and the spread of hantaviruses in rodent populations. Here, we investigated the importance of kinclustering and dispersal in hantavirus transmission by combining a fine-scale spatiotemporal survey (4 km2) and a population genetics approach. Two specific host-hantavirus systems were identified and monitored: the bank vole Myodes, earlier Clethrionomys glareolus--Puumala virus and the common vole Microtus arvalis--Tula virus. Sex, age and landscape characteristics significantly influenced the spatial distribution of infections in voles. The absence of temporal stability in the spatial distributions of viruses suggested that dispersal is likely to play a role in virus propagation. Analysing vole kinship from microsatellite markers, we found that infected voles were more closely related to each other than non-infected ones. Winter kin-clustering, shared colonies within matrilineages or delayed dispersal could explain this pattern. These two last results hold, whatever the host-hantavirus system considered. This supports the roles of relatedness and dispersal as general features for hantavirus transmission.

  1. Response of two prairie forbs to repeated vole herbivory. (United States)

    Sullivan, Amy T; Howe, Henry F


    Vertebrate herbivores as diverse as ungulates, geese, and rabbits preferentially feed on plants that have previously experienced herbivory. Here, we ask whether smaller grassland "cryptic consumers" such as voles (Microtus ochrogaster and M. pennsylvanicus) preferentially clip (cut stems for access to leaves or seeds) or avoid previously clipped individuals of two tallgrass prairie species (Desmanthus illinoensis and Echinacea purpurea) within a growing season. Further, we ask how these plants respond to repeated clipping within a growing season, and whether the effects of this herbivory last into the subsequent growing season. Voles preferentially clipped stems of D. illinoensis and E. purpurea plants that had been previously clipped. The exception was indiscriminant clipping of stems of E. purpurea late in the growing season when its achenes, a favorite vole food, ripened. For D. illinoensis, repeated clipping resulted in a 59% reduction in biomass, 42% lower ratio of reproductive to vegetative biomass, and 57% fewer seeds produced per plant compared with unclipped plants. These effects lasted into the following growing season in which plants were protected from voles. In contrast, the only effect of repeated clipping for E. purpurea was that the number of achenes per plant was substantially reduced by three episodes of clipping. This effect did not carry over to the next growing season. Such differences in D. illinoensis and E. purpurea response to repeated stem clipping by voles offer insights into how these small rodents can effect major changes in composition and dominance in grassland communities.

  2. Description of Paranoplocephala yoccozi n. sp. (Cestoda: Anoplocephalidae from the snow vole Chionomys nivalis in France, with a review of anoplocephalid cestodes of snow voles in Europe

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    Haukisalmi V.


    Full Text Available We describe Paranoplocephala yoccozi n. sp. (Cestoda: Anoplocephalidae from the snow vole Chionomys nivalis in Bourg-Saint-Maurice, French Alps, compare it with several related species from rodents, and review the anoplocephalid cestodes of snow voles in Europe. Paranoplocephala yoccozi n. sp. is primarily distinguished from the related species by its large scolex of characteristic shape, robust neck region, and the structure of the cirrus sac, vitellarium and vagina. We show that the anoplocephalid cestodes of snow voles in Europe, representing the genera Anoplocephaloides and Paranoplocephala, include at least seven species. This fauna consists primarily of species that snow voles share with other voles inhabiting the high-mountain areas. Some of the species, including P. yoccozi n. sp., appear to have a very localized distribution, which is assumed to be a consequence of the historical fragmentation of snow vole populations.

  3. Fungal-mediated multitrophic interactions--do grass endophytes in diet protect voles from predators?

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    Susanna Saari

    Full Text Available Plant-associated micro-organisms such as mycotoxin-producing endophytes commonly have direct negative effects on herbivores. These effects may be carried over to natural enemies of the herbivores, but this has been rarely explored. We examined how feeding on Neotyphodium endophyte infected (E+ and endophyte free (E- meadow ryegrass (Scherodonus pratensis affects body mass, population size and mobility of sibling voles (Microtus levis, and whether the diet mediates the vulnerability of voles to least weasel (Mustela nivalis nivalis predation. Because least weasels are known to be olfactory hunters, we also examined whether they are able to distinguish olfactory cues of voles fed on E+ and E- diets. Neither body mass of voles nor population size differed between diets. However, contrary to our prediction, least weasels preyed more often on voles fed with E- grass than on voles fed with E+ grass. The mobility of voles fed on E+ grass was reduced compared to voles fed on E- grass, but this effect was unrelated to risk of predation. Least weasels appeared unable to distinguish between excrement odours of voles between the two treatments. Our results suggest that consumption of endophytic grass is not directly deleterious to sibling voles. What's more, consumption of endophytes appears to be advantageous to voles by reducing risk of mammalian predation. Our study is thus the first to demonstrate an effect of plant-associated microbial symbionts on herbivore-predator interactions in vertebrate communities.

  4. Fungal-mediated multitrophic interactions--do grass endophytes in diet protect voles from predators? (United States)

    Saari, Susanna; Sundell, Janne; Huitu, Otso; Helander, Marjo; Ketoja, Elise; Ylönen, Hannu; Saikkonen, Kari


    Plant-associated micro-organisms such as mycotoxin-producing endophytes commonly have direct negative effects on herbivores. These effects may be carried over to natural enemies of the herbivores, but this has been rarely explored. We examined how feeding on Neotyphodium endophyte infected (E+) and endophyte free (E-) meadow ryegrass (Scherodonus pratensis) affects body mass, population size and mobility of sibling voles (Microtus levis), and whether the diet mediates the vulnerability of voles to least weasel (Mustela nivalis nivalis) predation. Because least weasels are known to be olfactory hunters, we also examined whether they are able to distinguish olfactory cues of voles fed on E+ and E- diets. Neither body mass of voles nor population size differed between diets. However, contrary to our prediction, least weasels preyed more often on voles fed with E- grass than on voles fed with E+ grass. The mobility of voles fed on E+ grass was reduced compared to voles fed on E- grass, but this effect was unrelated to risk of predation. Least weasels appeared unable to distinguish between excrement odours of voles between the two treatments. Our results suggest that consumption of endophytic grass is not directly deleterious to sibling voles. What's more, consumption of endophytes appears to be advantageous to voles by reducing risk of mammalian predation. Our study is thus the first to demonstrate an effect of plant-associated microbial symbionts on herbivore-predator interactions in vertebrate communities.

  5. Ecological Niche Modelling of Bank Voles in Western Europe

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    Sara Amirpour Haredasht


    Full Text Available The bank vole (Myodes glareolus is the natural host of Puumala virus (PUUV in vast areas of Europe. PUUV is one of the hantaviruses which are transmitted to humans by infected rodents. PUUV causes a general mild form of hemorrhagic fever with renal syndrome (HFRS called nephropathia epidemica (NE. Vector-borne and zoonotic diseases generally display clear spatial patterns due to different space-dependent factors. Land cover influences disease transmission by controlling both the spatial distribution of vectors or hosts, as well as by facilitating the human contact with them. In this study the use of ecological niche modelling (ENM for predicting the geographical distribution of bank vole population on the basis of spatial climate information is tested. The Genetic Algorithm for Rule-set Prediction (GARP is used to model the ecological niche of bank voles in Western Europe. The meteorological data, land cover types and geo-referenced points representing the locations of the bank voles (latitude/longitude in the study area are used as the primary model input value. The predictive accuracy of the bank vole ecologic niche model was significant (training accuracy of 86%. The output of the GARP models based on the 50% subsets of points used for testing the model showed an accuracy of 75%. Compared with random models, the probability of such high predictivity was low (χ2 tests, p < 10−6. As such, the GARP models were predictive and the used ecologic niche model indeed indicates the ecologic requirements of bank voles. This approach successfully identified the areas of infection risk across the study area. The result suggests that the niche modelling approach can be implemented in a next step towards the development of new tools for monitoring the bank vole’s population.

  6. Empathy in prairie voles: Is this the consolation prize? (United States)

    Demas, Gregory E; Jasnow, Aaron M


    Although it is well known that humans and great apes are capable of engaging in consolation, an affiliative behavior directed toward distressed individuals, it has largely been assumed that this form of empathy was restricted to species possessing more complex cognitive functions. Recently, however, Burkett and colleagues (Science, 351, 375-378, 2016) have provided intriguing evidence that consolation behavior may be present in a socially monogamous rodent, the prairie vole. They also provide data to implicate the neuropeptide oxytocin in the regulation of this behavior, which suggests conserved neuroendocrine mechanisms between prairie voles and humans.

  7. Bot fly parasitism of the red-backed vole: host survival, infection risk, and population growth. (United States)

    Lemaître, Jérôme; Fortin, Daniel; Montiglio, Pierre-Olivier; Darveau, Marcel


    Parasites can play an important role in the dynamics of host populations, but empirical evidence remains sparse. We investigated the role of bot fly (Cuterebra spp.) parasitism in red-backed voles (Myodes gapperi) by first assessing the impacts of the parasite on the probability of vole survival under stressful conditions as well as on the reproductive activity of females. We then identified the main factors driving both the individual risk of infection and the abundance of bot flies inside red-backed voles. Finally, we evaluated the impacts of bot fly prevalence on the growth rate of vole populations between mid-July and mid-August. Thirty-six populations of red-backed voles were sampled in the boreal forest of Québec, Canada. The presence and the abundance of parasites in voles, two host life history traits (sex and body condition), three indices of habitat complexity (tree basal area, sapling basal area, coarse woody debris volume), and vole abundance were considered in models evaluating the effects of bot flies on host populations. We found that the probability of survival of red-backed voles in live traps decreased with bot fly infection. Both the individual risk of infection and the abundance of bot flies in red-backed voles were driven mainly by vole abundance rather than by the two host life history traits or the three variables of habitat complexity. Parasitism had population consequences: bot fly prevalence was linked to a decrease in short-term growth rate of vole populations over the summer. We found that bot flies have the potential to reduce survival of red-backed voles, an effect that may apply to large portions of populations.

  8. Development of genomic resources for the prairie vole (Microtus ochrogaster: construction of a BAC library and vole-mouse comparative cytogenetic map

    Directory of Open Access Journals (Sweden)

    Young Larry J


    Full Text Available Abstract Background The prairie vole (Microtus ochrogaster is a premier animal model for understanding the genetic and neurological basis of social behaviors. Unlike other biomedical models, prairie voles display a rich repertoire of social behaviors including the formation of long-term pair bonds and biparental care. However, due to a lack of genomic resources for this species, studies have been limited to a handful of candidate genes. To provide a substrate for future development of genomic resources for this unique model organism, we report the construction and characterization of a bacterial artificial chromosome (BAC library from a single male prairie vole and a prairie vole-mouse (Mus musculus comparative cytogenetic map. Results We constructed a prairie vole BAC library (CHORI-232 consisting of 194,267 recombinant clones with an average insert size of 139 kb. Hybridization-based screening of the gridded library at 19 loci established that the library has an average depth of coverage of ~10×. To obtain a small-scale sampling of the prairie vole genome, we generated 3884 BAC end-sequences totaling ~2.8 Mb. One-third of these BAC-end sequences could be mapped to unique locations in the mouse genome, thereby anchoring 1003 prairie vole BAC clones to an orthologous position in the mouse genome. Fluorescence in situ hybridization (FISH mapping of 62 prairie vole clones with BAC-end sequences mapping to orthologous positions in the mouse genome was used to develop a first-generation genome-wide prairie vole-mouse comparative cytogenetic map. While conserved synteny was observed between this pair of rodent genomes, rearrangements between the prairie vole and mouse genomes were detected, including a minimum of five inversions and 16 inter-chromosomal rearrangements. Conclusions The construction of the prairie vole BAC library and the vole-mouse comparative cytogenetic map represent the first genome-wide modern genomic resources developed for this

  9. Dioxin exposure in contaminated sawmill area: the use of molar teeth and bone of bank vole (Clethrionomys glareolus) and field vole (Microtus agrestis) as biomarkers. (United States)

    Murtomaa, Mari; Tervaniemi, Olli-Matti; Parviainen, Juha; Ruokojärvi, Päivi; Tuukkanen, Juha; Viluksela, Matti


    Developmental disorders of teeth are among the most sensitive targets of polychlorinated dibenzo-p-dioxin and -furan (PCDD/F) exposure. In rats, 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) reduces dose-dependently the size of molars, most severely the third lower molars. Dioxins also have effects on developing bone, including altered bone mineral density as well as reduced bending breaking force and stiffness. The aim of this study was to evaluate the use of the third lower molar and long bones as biomarkers of PCDD/F exposure in two wild vole species, the bank vole (Clethrionomys glareolus) and the field vole (Microtus agrestis) collected from a PCDD/F contaminated former sawmill area. Survey of soil and biota of the sawmill area indicated a PCDD/F contamination with a congener profile characteristic for the chlorophenol wood preservative Ky-5. The PCDD/F concentration in the bank vole was notably higher than in the field vole. The third molar of the bank vole was significantly smaller in dioxin-exposed animals compared to control group, while there was no difference between these two groups in the field vole. No significant alterations were observed in bone density and strength in either species except for reduced bending strength of the femur neck in bank vole males exposed to dioxins. Even though the bone changes are among the sensitive endpoints of dioxin-exposure, high variability due to age, size and gender limits their use as biomarkers of wildlife exposure. In conclusion, the size of molar teeth seems to be a sensitive and robust biomarker for PCDD/F exposure in wild bank vole populations and thus worth of further studies.

  10. Vole preference of bilberry along gradients of simulated moose density and site productivity. (United States)

    Pedersen, Simen; Andreassen, Harry P; Persson, Inga-Lill; Julkunen-Tiitto, Riitta; Danell, Kjell; Skarpe, Christina


    Browsing by large herbivores might either increase or decrease preference for the plant by other herbivores, depending on the plant response. Using a cafeteria test, we studied the preference by root voles (Microtus oeconomus [Pallas, 1776]) for bilberry (Vaccinium myrtillus L.) previously subjected to 4 levels of simulated moose (Alces alces [Linnaeus, 1758]) density. The different levels of moose density were simulated at population densities relevant for Fennoscandian conditions, in exclosures situated along a site productivity gradient. We expected: (i) voles to prefer bilberry from high productivity sites over low productivity sites; (ii) voles to prefer browsed bilberry, if plants allocate resources to compensatory growth or to avoid browsed bilberry if plants allocate resources to defense; (iii) these effects to increase with increasing simulated moose density; and (iv) the concentration of plant chemicals and the plant morphology to explain vole preference. Specifically, we predicted that voles would prefer: (i) plants with high nitrogen content; (ii) plants with low content of defensive substances; and (iii) tall plants with long shoots. Voles preferred bilberry from the high productivity sites compared to the low productivity sites. We also found an interaction between site productivity and simulated moose density, where voles preferred unbrowsed plants at low productivity sites and intermediate levels of browsing at high productivity sites. There was no effect of plant chemistry or morphology on vole preference. We conclude that moose browsing impacts the food preference of voles. With the current high densities of moose in Fennoscandia, this could potentially influence vole food selection and population dynamics over large geographical areas.

  11. Establishment of superovulation procedure in Japanese field vole, Microtus montebelli. (United States)

    Kageyama, Atsuko; Tanaka, Minako; Morita, Mami; Ushijima, Hitoshi; Tomogane, Hiroshi; Okada, Konosuke


    Japanese field vole (Microtus montebelli) is a wild-derived rodent and have unique characteristic. Thus, these species have been expected as model animal. This study was performed to develop novel superovulation procedure for Japanese field vole. First, when 30 IU pregnant mare's serum gonadotropin (PMSG) and 30 IU human chorionic gonadotropin (hCG) were administrated 48 hours apart, females showed higher response to hCG compared with three concentrations of PMSG. Second, to effectively induce ovulation on females after vaginal opening, they were mated with vasectomized male instead of hCG administration. Average number of ovulated oocytes using PMSG mating (13.9 ± 1.9 oocytes) was higher than PMSG-hCG (control; 6.9 ± 2.3 oocytes) or PMSG-hCG mating (6.8 ± 0.8 oocytes). Finally, we attempted superovulation using GnRH agonist (GnRHa). With this treatment, we speculated that GnRHa might induce endogenous luteinizing hormone releasing to cause ovulation. Such superovulation was performed with 30 IU PMSG and different concentration of 20% polyvinylpyrrolidone-GnRHa (15, 30, 45, and 60 μg/kg). As results, average number of ovulated oocytes was highest with 30 μg/kg GnRHa (14.5 ± 4.1 oocytes). The numbers of ovulated oocytes of other concentrations were 5.0 ± 1.4 (15 μg/kg), 12.8 ± 2.7 (45 μg/kg), and 8.8 ± 3.7 oocytes (60 μg/kg). Nuclear status of most collected oocytes was the second meiotic division (range, 94.3%-100%). These superovulation procedures will be useful for development of in vitro culture systems and assisted reproductive technologies for not only Japanese field vole but also other voles. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. How predation and landscape fragmentation affect vole population dynamics

    DEFF Research Database (Denmark)

    Dalkvist, Trine; Sibly, Richard; Topping, Christopher John


    on vole population dynamics of making predators more specialised, of altering the breeding season, and increasing the level of habitat fragmentation. We found that fragmentation as well as the presence of specialist predators are necessary for the occurrence of population cycles. Habitat fragmentation...... to unravel in field experiments. We hope our results will help understand the reasons for cycle gradients observed in other areas. Our results clearly demonstrate the importance of landscape fragmentation for population cycling and we recommend that the degree of fragmentation be more fully considered...

  13. How Predation and Landscape Fragmentation Affect Vole Population Dynamics

    DEFF Research Database (Denmark)

    Dalkvist, Trine; Sibly, Richard M.; Topping, Chris J.


    on vole population dynamics of making predators more specialised, of altering the breeding season, and increasing the level of habitat fragmentation. We found that fragmentation as well as the presence of specialist predators are necessary for the occurrence of population cycles. Habitat fragmentation...... to unravel in field experiments. We hope our results will help understand the reasons for cycle gradients observed in other areas. Our results clearly demonstrate the importance of landscape fragmentation for population cycling and we recommend that the degree of fragmentation be more fully considered...

  14. Efficient transmission and characterization of Creutzfeldt-Jakob disease strains in bank voles.

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    Romolo Nonno


    Full Text Available Transmission of prions between species is limited by the "species barrier," which hampers a full characterization of human prion strains in the mouse model. We report that the efficiency of primary transmission of prions from Creutzfeldt-Jakob disease patients to a wild rodent species, the bank vole (Clethrionomys glareolus, is comparable to that reported in transgenic mice carrying human prion protein, in spite of a low prion protein-sequence homology between man and vole. Voles infected with sporadic and genetic Creutzfeldt-Jakob disease isolates show strain-specific patterns of spongiform degeneration and pathological prion protein-deposition, and accumulate protease-resistant prion protein with biochemical properties similar to the human counterpart. Adaptation of genetic Creutzfeldt-Jakob disease isolates to voles shows little or no evidence of a transmission barrier, in contrast to the striking barriers observed during transmission of mouse, hamster, and sheep prions to voles. Our results imply that in voles there is no clear relationship between the degree of homology of the prion protein of the donor and recipient species and susceptibility, consistent with the view that the prion strain gives a major contribution to the species barrier. The vole is therefore a valuable model to study human prion diversity and, being susceptible to a range of animal prions, represents a unique tool for comparing isolates from different species.

  15. Efficient transmission and characterization of creutzfeldt-jakob disease strains in bank voles.

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    Full Text Available Transmission of prions between species is limited by the "species barrier," which hampers a full characterization of human prion strains in the mouse model. We report that the efficiency of primary transmission of prions from Creutzfeldt-Jakob disease patients to a wild rodent species, the bank vole (Clethrionomys glareolus, is comparable to that reported in transgenic mice carrying human prion protein, in spite of a low prion protein-sequence homology between man and vole. Voles infected with sporadic and genetic Creutzfeldt-Jakob disease isolates show strain-specific patterns of spongiform degeneration and pathological prion protein-deposition, and accumulate protease-resistant prion protein with biochemical properties similar to the human counterpart. Adaptation of genetic Creutzfeldt-Jakob disease isolates to voles shows little or no evidence of a transmission barrier, in contrast to the striking barriers observed during transmission of mouse, hamster, and sheep prions to voles. Our results imply that in voles there is no clear relationship between the degree of homology of the prion protein of the donor and recipient species and susceptibility, consistent with the view that the prion strain gives a major contribution to the species barrier. The vole is therefore a valuable model to study human prion diversity and, being susceptible to a range of animal prions, represents a unique tool for comparing isolates from different species.

  16. Effects of short term bioturbation by common voles on biogeochemical soil variables.

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    Burkhard Wilske

    Full Text Available Bioturbation contributes to soil formation and ecosystem functioning. With respect to the active transport of matter by voles, bioturbation may be considered as a very dynamic process among those shaping soil formation and biogeochemistry. The present study aimed at characterizing and quantifying the effects of bioturbation by voles on soil water relations and carbon and nitrogen stocks. Bioturbation effects were examined based on a field set up in a luvic arenosol comprising of eight 50 × 50 m enclosures with greatly different numbers of common vole (Microtus arvalis L., ca. 35-150 individuals ha-1 mth-1. Eleven key soil variables were analyzed: bulk density, infiltration rate, saturated hydraulic conductivity, water holding capacity, contents of soil organic carbon (SOC and total nitrogen (N, CO2 emission potential, C/N ratio, the stable isotopic signatures of 13C and 15N, and pH. The highest vole densities were hypothesized to cause significant changes in some variables within 21 months. Results showed that land history had still a major influence, as eight key variables displayed an additional or sole influence of topography. However, the δ15N at depths of 10-20 and 20-30 cm decreased and increased with increasing vole numbers, respectively. Also the CO2 emission potential from soil collected at a depth of 15-30 cm decreased and the C/N ratio at 5-10 cm depth narrowed with increasing vole numbers. These variables indicated the first influence of voles on the respective mineralization processes in some soil layers. Tendencies of vole activity homogenizing SOC and N contents across layers were not significant. The results of the other seven key variables did not confirm significant effects of voles. Thus overall, we found mainly a first response of variables that are indicative for changes in biogeochemical dynamics but not yet of those representing changes in pools.

  17. Co-infection of Borrelia afzelii and Bartonella spp. in bank voles from a suburban forest. (United States)

    Buffet, Jean-Philippe; Marsot, Maud; Vaumourin, Elise; Gasqui, Patrick; Masséglia, Sébastien; Marcheteau, Elie; Huet, Dominique; Chapuis, Jean-Louis; Pisanu, Benoit; Ferquel, Elisabeth; Halos, Lénaïg; Vourc'h, Gwenaël; Vayssier-Taussat, Muriel


    We report the molecular detection of Borrelia afzelii (11%) and Bartonella spp. (56%) in 447 bank voles trapped in a suburban forest in France. Adult voles were infected by significantly more Borrelia afzelii than juveniles (pBartonella spp. between young and adult individuals (p=0.914). Six percent of the animals were co-infected by both bacteria. Analysis of the bank vole carrier status for either pathogen indicated that co-infections occur randomly (p=0.94, CI(95)=[0.53; 1.47]). Sequence analysis revealed that bank voles were infected by a single genotype of Borrelia afzelii and by 32 different Bartonella spp. genotypes, related to three known species specific to rodents (B. taylorii, B. grahamii and B. doshiae) and also two as yet unidentified Bartonella species. Our findings confirm that rodents harbor high levels of potential human pathogens; therefore, widespread surveillance should be undertaken in areas where humans may encounter rodents.

  18. Spontaneous emergence of overgrown molar teeth in a colony of Prairie voles (Microtus ochrogaster)

    Institute of Scientific and Technical Information of China (English)

    Andrew H Jheon; Michaela Prochazkova; Michael Sherman; Devanand S Manoli; Nirao M Shah; Lawrence Carbone; Ophir Klein


    Continuously growing incisors are common to all rodents, which include the Microtus genus of voles. However, unlike many rodents, voles also possess continuously growing molars. Here, we report spontaneous molar defects in a population of Prairie voles (Microtus ochrogaster). We identified bilateral protuberances on the ventral surface of the mandible in several voles in our colony. In some cases, the protuberances broke through the cortical bone. The mandibular molars became exposed and infected, and the maxillary molars entered the cranial vault. Visualisation upon soft tissue removal and microcomputed tomography (microCT) analyses confirmed that the protuberances were caused by the overgrowth of the apical ends of the molar teeth. We speculate that the unrestricted growth of the molars was due to the misregulation of the molar dental stem cell niche. Further study of this molar phenotype may yield additional insight into stem cell regulation and the evolution and development of continuously growing teeth.

  19. Amak Island trip report - notes on the Amak song sparrow and Amak vole (United States)

    US Fish and Wildlife Service, Department of the Interior — Both the Amak Island song sparrow (Melospiza melodia amaka) and Amak vole (Microtus oeconomus amakensis) are currently category 2 candidate species under the...

  20. Landscape structure mediates the effects of a stressor on field vole populations

    DEFF Research Database (Denmark)

    Dalkvist, Trine; Sibly, Richard M.; Topping, Christopher John


    Spatio-temporal landscape heterogeneity has rarely been considered in population-level impact assessments. Here we test whether landscape heterogeneity is important by examining the case of a pesticide applied seasonally to orchards which may affect non-target vole populations, using a validated...... ecologically realistic and spatially explicit agent-based model. Voles thrive in unmanaged grasslands and untreated orchards but are particularly exposed to applied pesticide treatments during dispersal between optimal habitats. We therefore hypothesised that vole populations do better (1) in landscapes...... containing more grassland and (2) where areas of grassland are closer to orchards, but (3) do worse if larger areas of orchards are treated with pesticide. To test these hyposeses we made appropriate manipulations to a model landscape occupied by field voles. Pesticide application reduced model population...

  1. Experimental Infection of voles with Francisella tularensis indicates their amplification role in tularemia outbreaks.

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    Heidi Rossow

    Full Text Available Tularemia outbreaks in humans have been linked to fluctuations in rodent population density, but the mode of bacterial maintenance in nature is unclear. Here we report on an experiment to investigate the pathogenesis of Francisella tularensis infection in wild rodents, and thereby assess their potential to spread the bacterium. We infected 20 field voles (Microtus agrestis and 12 bank voles (Myodes glareolus with a strain of F. tularensis ssp. holarctica isolated from a human patient. Upon euthanasia or death, voles were necropsied and specimens collected for histological assessment and identification of bacteria by immunohistology and PCR. Bacterial excretion and a rapid lethal clinical course with pathological changes consistent with bacteremia and tissue necrosis were observed in infected animals. The results support a role for voles as an amplification host of F. tularensis, as excreta and, in particular, carcasses with high bacterial burden could serve as a source for environmental contamination.

  2. A genetic linkage map and comparative mapping of the prairie vole (Microtus ochrogaster genome

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    Young Larry J


    Full Text Available Abstract Background The prairie vole (Microtus ochrogaster is an emerging rodent model for investigating the genetics, evolution and molecular mechanisms of social behavior. Though a karyotype for the prairie vole has been reported and low-resolution comparative cytogenetic analyses have been done in this species, other basic genetic resources for this species, such as a genetic linkage map, are lacking. Results Here we report the construction of a genome-wide linkage map of the prairie vole. The linkage map consists of 406 markers that are spaced on average every 7 Mb and span an estimated ~90% of the genome. The sex average length of the linkage map is 1707 cM, which, like other Muroid rodent linkage maps, is on the lower end of the length distribution of linkage maps reported to date for placental mammals. Linkage groups were assigned to 19 out of the 26 prairie vole autosomes as well as the X chromosome. Comparative analyses of the prairie vole linkage map based on the location of 387 Type I markers identified 61 large blocks of synteny with the mouse genome. In addition, the results of the comparative analyses revealed a potential elevated rate of inversions in the prairie vole lineage compared to the laboratory mouse and rat. Conclusions A genetic linkage map of the prairie vole has been constructed and represents the fourth genome-wide high-resolution linkage map reported for Muroid rodents and the first for a member of the Arvicolinae sub-family. This resource will advance studies designed to dissect the genetic basis of a variety of social behaviors and other traits in the prairie vole as well as our understanding of genome evolution in the genus Microtus.

  3. Revisiting the “visible burrow system”: The impact of the group, social rank, and gender on voles under owl attack. (United States)

    Bodek, Sivan; Eilam, David


    In the present study, corticosterone levels and behavior were compared between voles (Microtus socialis) that were attacked by a barn owl (Tyto alba) and voles that did not experience such attack. Both female and male voles were exposed to the owl either together with their group mates or when socially isolated. As hypothesized, corticosterone levels were higher in voles after the owl attack, and were higher in females than in males. However, blood corticosterone was higher in voles that experienced the attack in groups compared with the socially-isolated voles. The latter result seems enigmatic, since group members usually benefit from the “social buffering” conferred by their group-mates. It is suggested that contagious vigilance among group members accounts for the higher mean corticosterone level in grouped compared to socially-isolated voles, overshadowing the possible impact of social buffering. We also found a negative correlation between body mass and corticosterone level, with more high-mass voles showing low corticosterone levels compared with low mass voles. This finding accords with a previous study in which the behavior of high-mass voles was less affected by owl attack compared to low-mass voles. The novelty of the present results therefore lies in supporting, at the hormonal level, past behavioral findings in rats and voles, and in demonstrating that high-mass voles, by virtue of their physical strength and perhaps also their life experience, are less stressed by the owl attack and become the leaders and stabilizers of their groups.

  4. Prairie voles as a novel model of socially facilitated excessive drinking. (United States)

    Anacker, Allison M J; Loftis, Jennifer M; Kaur, Simranjit; Ryabinin, Andrey E


    Social relationships strongly affect alcohol drinking in humans. Traditional laboratory rodents do not exhibit social affiliations with specific peers, and cannot adequately model how such relationships impact drinking. The prairie vole is a socially monogamous rodent used to study social bonds. The present study tested the prairie vole as a potential model for the effects of social affiliations on alcohol drinking. Same-sex adult sibling prairie voles were paired for five days, and then either separated into individual cages, or housed in pairs. Starting at the time of separation, the voles received unlimited access to alcohol in a two-bottle choice test versus water. Pair-housed siblings exhibited higher preference for alcohol, but not saccharin, than singly housed voles. There was a significant correlation between the amount of alcohol consumed by each member of a pair when they were housed together (r = 0.79), but not when housed apart (r = 0.20). Following automated analysis of circadian patterns of fluid consumption indicating peak fluid intake before and after the dark phase, a limited access two-hour two-bottle choice procedure was established. Drinking in this procedure resulted in physiologically relevant blood ethanol concentrations and increased Fos immunoreactivity in perioculomotor urocortin containing neurons (but not in nucleus accumbens or central nucleus of the amygdala). The high ethanol preference and sensitivity to social manipulation indicate that prairie voles can serve to model social influences on excessive drinking.

  5. BAC-based sequencing of behaviorally-relevant genes in the prairie vole.

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    Lisa A McGraw

    Full Text Available The prairie vole (Microtus ochrogaster is an important model organism for the study of social behavior, yet our ability to correlate genes and behavior in this species has been limited due to a lack of genetic and genomic resources. Here we report the BAC-based targeted sequencing of behaviorally-relevant genes and flanking regions in the prairie vole. A total of 6.4 Mb of non-redundant or haplotype-specific sequence assemblies were generated that span the partial or complete sequence of 21 behaviorally-relevant genes as well as an additional 55 flanking genes. Estimates of nucleotide diversity from 13 loci based on alignments of 1.7 Mb of haplotype-specific assemblies revealed an average pair-wise heterozygosity (8.4×10(-3. Comparative analyses of the prairie vole proteins encoded by the behaviorally-relevant genes identified >100 substitutions specific to the prairie vole lineage. Finally, our sequencing data indicate that a duplication of the prairie vole AVPR1A locus likely originated from a recent segmental duplication spanning a minimum of 105 kb. In summary, the results of our study provide the genomic resources necessary for the molecular and genetic characterization of a high-priority set of candidate genes for regulating social behavior in the prairie vole.

  6. Who are the bosses? Group influence on the behavior of voles following owl attack. (United States)

    Kleiman, Michal; Bodek, Sivan; Eilam, David


    Individual members of a group must conform to the group norms, as they may otherwise become isolated from the group or the group may split. On the other hand, social groups usually comprise various social ranks and display a differential division of labor and consequently different behaviors. The present study was aimed at examining how the above factors are manifested in social voles that had experienced owl attack. Here, we reconfirm the findings of past studies: that grouped voles converge to display similar behavior after owl attack. In addition, we found that high-mass voles were more active in the open sectors of the experimental set-ups both before and after the owl attack, whereas low-mass voles dichotomized to those that increased and those that decreased their activity in the open following owl attack. Taking body mass as a proxy for social rank, it is suggested that as a consequence of their larger size and of their experience and physical strength, high-mass voles both presented an exemplary model for the low-mass voles and, accordingly, assumed leadership and stabilized their group's behavior. We also suggest a hypothetical model for the propagation of behavior in hierarchical groups.

  7. Phenomenon in the Evolution of Voles (Mammalia, Rodentia, Arvicolidae

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    Rekovets L. I.


    Full Text Available This paper presents analytical results of the study of adaptatiogenesis within the family Arvicolidae (Mammalia, Rodentia based of morphological changes of the most functional characters of their masticatory apparatus — dental system — through time. The main directions of the morphological differentiation in parallel evolution of the arvicolid tooth type within the Cricetidae and Arvicolidae during late Miocene and Pliocene were identified and substantiated. It is shown that such unique morphological structure as the arvicolid tooth type has provided a relatively high rate of evolution of voles and a wide range of their adaptive radiation, as well as has determined their taxonomic and ecological diversity. The optimality of the current state of this group and evaluation of evolutionary prospects of Arvicolidae were presented and substantiated here as a phenomenon in their evolution.

  8. In vitro culture and in vitro fertilization techniques for prairie voles (Microtus ochrogaster). (United States)

    Horie, Kengo; Hidema, Shizu; Hirayama, Takashi; Nishimori, Katsuhiko


    Prairie vole (Microtus ochrogaster) is a highly social animal and is a commonly used animal model for neuropsychopharmacological and psychiatric studies. To date, only a few reports on the development of transgenic prairie voles which was primarily due to the suboptimal development of assisted reproductive technology (ART) in prairie voles. Limitations in ART further hinder the development of genetically modified prairie voles such as the application of conventional gene targeting technologies using embryonic stem (ES) or induced pluripotent stem (iPS) cells to generate chimeric prairie voles. Moreover, recent advancement in genome-editing tools such as transcription activator-like effector nuclease (TALEN) and clustered regulatory interspaced short palindromic repeat (CRISPR)/Cas technology provide an unprecedented opportunity to create gene targeting animal model and the development of ART in prairie voles is necessary for future development of novel transgenic prairie vole model. We have established efficient method for in vitro embryo culture and sperm cryopreservation with high fertilization rate. In G-1 PLUS and G-2 PLUS sequential culture condition, 81.0% (# of Blastocysts/total n) of one-cell embryos developed to blastocysts. In contrary, no embryos were developed to blastocyst stage in KSOM medium (0/total # of embryos in culture). In vitro fertilization rate using fresh and frozen-thawed sperm was 32.6% and 29.3%, respectively. This is the first report of IVF using cryopreserved prairie vole sperm. We employed mouse IVF methods in prairie voles and optimize culture conditions using human G-1/G-2 PLUS sequential culture method that resulted in high embryonic development rate. The development in vole reproductive technology will facilitate the generation of transgenic voles in the future.

  9. Comparative distribution of central neuropeptide Y (NPY) in the prairie (Microtus ochrogaster) and meadow (M. pennsylvanicus) vole. (United States)

    Hostetler, Caroline M; Hitchcock, Leah N; Anacker, Allison M J; Young, Larry J; Ryabinin, Andrey E


    Neuropeptide Y (NPY) has been implicated as a modulator of social behavior, often in a species-specific manner. Comparative studies of closely related vole species are particularly useful for identifying neural systems involved in social behaviors in both voles and humans. In the present study, immunohistochemistry was performed to compare NPY-like immunoreactivity (-ir) in brain tissue of the socially monogamous prairie vole and non-monogamous meadow vole. Species differences in NPY-ir were observed in a number of regions including the cortex, extended amygdala, septal area, suprachiasmatic nucleus, and intergeniculate leaf. Meadow voles had higher NPY-ir in all these regions as compared to prairie voles. No differences were observed in the striatum or hippocampus. The extended amygdala and lateral septum are regions that play a key role in regulation of monogamous behaviors such as pair bonding and paternal care. The present study suggests NPY in these regions may be an additional modulator of these species-specific social behaviors. Meadow voles had moderately higher NPY-ir in a number of hypothalamic regions, especially in the suprachiasmatic nucleus. Meadow voles also had much higher levels of NPY-ir in the intergeniculate leaflet, another key region in the regulation of circadian rhythms. Overall, species differences in NPY-ir were observed in a number of brain regions implicated in emotion, stress, circadian, and social behaviors. These findings provide additional support for a role for the NPY system in species-typical social behaviors.

  10. Revision of bank vole Clethrionomys glareolus (Schreber, 1780 (Mammalia, Rodentia distribution in Serbia and Montenegro

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    Paunović M.


    Full Text Available The present article represents a complete review of all published data (with corrections on bank vole Clethrionomys glareolus distribution in Serbia and Montenegro. On the other hand, data of 63 unpublished records stored in the period from 1956 to 1983 in the Mammal Study Collection of the Natural History Museum, Belgrade had not been processed until now. In the period from 1992 to 2004, 29 new findings were recorded, 12 of them outside the currently known area of distribution. New data reveal a wider distribution of bank vole than was known until now, completing and partly modifying previous knowledge about this rodent's bionomy and ecology in Serbia and Montenegro. The occurrence of bank vole in the Prokletije Mountains, Kosovo and Metohija represents its highest known altitude in Europe (2500 m. On the basis of these new data and observations, we can conclude that bank vole is continuously present in small and linear fragments of autochthonous woodlands on plains and hills, and that there are no large discontinuities in its distribution in Serbia and Montenegro, as was assumed earlier. In efforts to preserve overall biological diversity, the example of the bank vole underlines the need to intensify protection and management of woodlands especially remaining fragments of forests on plains and in hills.

  11. Autolabelling of gamasid mites and fleas in nests of red voles in winter (according to radioisotope labelling data)

    Energy Technology Data Exchange (ETDEWEB)

    Al' bov, S.A.; Lavrenchenko, L.A.; Nikolaeva, G.A.

    Data concerning trophic associations between gamasid mites and fleas in cohabitation with red voles in nests in winter were presented and discussed. Red voles (Cl. glareolus) were trapped, labelled with radioactive cobalt and radioactive glycine, released and traced with the aid of radiometers. H. nidi and C. penicilliger were found to be the most numerous among the mites and fleas in the winter nests of the voles and were the most actively feeding species. H. nidi and C. penicilliger numbers increased with the increase of time of use of the nests by the voles and had little relationship to the abundance of these species in the nests. Other species assumed that the connection between the gamasid mites, fleas and voles was topical rather than trophic. 11 references, 4 figures.

  12. Morphotype analysis of the sibling vole (Microtus rossiaemeridionalis) casually introduced to the Russian Far East. (United States)

    Tiunov, Mikhail Petrovich; Kartavtseva, Irina Vasiljevna; Lapin, Alexander Sergeevich


    Here, we present the morphotypic variety of the m1 and M3 teeth diagnostics for the recently formed isolated population of the sibling vole in Far Eastern Russia. In the Far Eastern population, the prevalence of the individuals with m1 with a complicated crown of the forward unpaired loop of the paraconid is characteristic. Namely, m1 in these individuals shows well-expressed sixth exterior and fifth interior salient angles. The structure of the M3 morphotypes is also unique in the sibling voles in Far Eastern Russia. The dominant morphotypes were typica (47 %) and simplex (45 %), whereas the abundance of the duplicata morphotype was 0.08 %. The frequencies of various m1 and M3 morphotypes found in casually introduced sibling voles in the Far East are not typical of any previously studied Microtus rossiaemeridionalis population.

  13. Infection of SARS-CoV on juvenile and adult Brandt's vole Microtus brandtii

    Institute of Scientific and Technical Information of China (English)

    GAO Hong; PENG Jingpian; DENG Wei; SHI Dazhao; BAO Linlin; WANG Dehua; ZHANG Binglin; QIN Chuan; ZHANG Zhibin


    We studied the infectious effect of SARS-CoV virus on juvenile and adult Brandt's Vole (Microtus brandtii) by nasal cavity spraying method (CCID50 is 105.7). SARS virus caused serious deaths in adults. The death adults demonstrated hemorrhage from mouth, nasal cavity and intestine, hemorrhageious interstitial pneumonia and gore in liver, spleen and kidney. The survival adults demonstrated local hemorrhagic spot in lung and emphysema, but the other organs showed no pathological abnormality. SARS virus caused no deaths in juveniles, but locomotion of infected juveniles became slower. In the early stage, there was local pneumonia in lung and SARS viruses were isolated from the pathological tissue. Only one control juvenile lived and the infected juvenile showed local pneumonia in lung. The results demonstrated that SARS-CoV infected Brandt's vole seriously and adults were more susceptive to SARS-CoV than juveniles. The Brandt's vole may be a potential animal model for SARS research.

  14. Intraspecific variation in the energetics of the Cabrera vole. (United States)

    Castellanos-Frías, Elena; García-Perea, Rosa; Gisbert, Julio; Bozinovic, Francisco; Virgós, Emilio


    Basal metabolic rate (BMR) is an intensively topic studied in ecophysiology for the purpose of understanding energy budgets of the species, variations of energy expenditure during their diary activities and physiological acclimatization to the environment. Establishing how the metabolism is assembled to the environment can provide valuable data to improve conservation strategies of endangered species. In this sense, metabolic differences associated to habitats have been widely reported in the interspecific level, however little is known about the intraspecific view of BMR under an environmental gradient. In this study, we researched the effect of the habitat on metabolic rate of an Iberian endemic species: Iberomys cabrerae. Animals were captured in different subpopulations of its altitudinal range and their MR was studied over a thermal gradient. MR was analyzed through a Linear Mixed Model (LMM) in which, in addition to thermal effects, the bioclimatic zone and sex also influenced the metabolism of the species. The beginning of thermoneutrality zone was set on 26.5°C and RMR was 2.3ml O2g(-1)h(-1), intermediate between both bioclimatic zones. Supramediterranean subpopulations started the Tlc earlier (24.9°C) and had higher RMR than the mesomediterranean ones (26.9°C). The thermal environment together with primary productivity conditions could explain this difference in the metabolic behaviour of the Cabrera voles.

  15. Late Pleistocene voles (Arvicolinae, Rodentia) from the Baranica Cave (Serbia) (United States)

    Bogićević, Katarina; Nenadić, Draženko; Mihailović, Dušan


    Baranica is a cave system situated in the south-eastern part of Serbia, four kilometers south to Knjaževac, on the right bank of the Trgovi\\vski Timok. The investigations in Baranica were conducted from 1994 to 1997 by the Faculty of Philosophy from Belgrade and the National Museum of Knjaževac. Four geological layers of Quaternary age were recovered. The abundance of remains of both large and small mammals was noticed in the early phase of the research. In this paper, the remains of eight vole species are described: Arvicola terrestris (Linnaeus, 1758), Chionomys nivalis (Martins, 1842), Microtus (Microtus) arvalis (Pallas, 1778) and Microtus (Microtus) agrestis (Linnaeus, 1761), Microtus (Stenocranius) gregalis (Pallas, 1779), Microtus (Terricola) subterraneus (de Sélys-Longchamps, 1836), Clethrionomys glareolus (Schreber, 1780) and Lagurus lagurus (Pallas, 1773). Among them, steppe and open area inhabitants prevail. Based on the evolutionary level and dimensions of the Arvicola terrestris molars, as well as the overall characteristics of the fauna, it was concluded that the deposits were formed in the last glacial period of the Late Pleistocene. These conclusions are rather consistent with the absolute dating of large mammal bones (23.520 ± 110 B.P. for Layer 2 and 35.780 ± 320 B.P. for Layer 4).

  16. [Ecology of indigenious arbovirus in Alsace. Tick Central European Encephalitis. I.--Complex Ixodes ricinus--bank voles. II.--Study of bank voles population immunity. III.--Virologic results in bank voles population (author's transl)]. (United States)

    Chatelain, J; Hannoun, C; Rodhain, F; Chatelain, J; Hannoun, C; Salmon, A M; Ardoin, P; Chatelain, J; Hannoun, C; Sureau, P


    I.--After showing that bank voles are parasited only by Ixodes ricinus larvae, the authors attempt to found different factors (demographic, biometric, and sexual) who favor individual parasitism. The authors conclude to absent of anti tick immunity for this rodent specie. II.--The search for anti-central european encephalitis antibodies (I.H.A.) are shown that 2 p. cent animals were immuns. Yearly and monthly chronologies of antibodies apparition are shown, factors favoring the growth of specific Central european encephalitis antibodies are discussed. III.--The Central european encephalitis tick viral infection of bank vole is studied according to the number of viral strains isolated from different viscera. The monthly chronology of this infection is shown.

  17. Cholinesterase inhibition in meadow voles Microtus pennsylvanicus following field applications of Orthene (United States)

    Jett, D.A.


    Brain acetylcholinesterase activity in field-caught meadow voles (Microtus pennsylvanicus) was depressed after a field-spray of Orthene (acephate: acetylphosphoramidothioic acid O,S-dimethyl ester) by as much as 32% in 1982 and 38% in 1983. Short-term recovery was demonstrated and occurred in a time-dependent fashion in 1982. Plasma cholinesterase levels were move variable but also were depressed. Residues were detected in vegetation samples and in the gastrointestinal tracts of exposed voles. Residues in vegetation were diluted or absent 7 to 8 d following the treatment.

  18. Developmental expression of estrogen receptor beta in the brain of prairie voles (Microtus ochrogaster). (United States)

    Ploskonka, Stephanie D; Eaton, Jennifer L; Carr, Michael S; Schmidt, Jennifer V; Cushing, Bruce S


    Here, for the first time, the expression of estrogen receptor beta (ERβ) is characterized in the brains of the highly prosocial prairie vole (Microtus ochrogaster). ERβ immunoreactivity was compared in weanlings (postnatal Day 21) and adult males and females. The results indicate several major findings. First, unlike ERα, ERβ expression is not sexually dimorphic. Second, the adult pattern of ERβ-IR is established at the time of weaning, as there were no age-dependent effects on distribution. Finally, ERβ does not appear to be as widely distributed in voles compared with rats and mice. High levels of ERβ-IR were observed in several regions/nuclei within the medial pre-optic area, ventrolateral pre-optic nuclei, and in the hypothalamus, especially in the paraventricular and supraoptic nuclei. The visualization of ERβ in prairie voles is important as the socially monogamous prairie vole functions as a human relevant model system for studying the expression of social behavior and social deficit disorders. Future studies will now be able to determine the effect of treatments on the expression and/or development of ERβ in this highly social species.

  19. Sperm investment in male meadow voles is affected by the condition of the nearby male conspecifics. (United States)

    Vaughn, Ashlee A; Delbarco-Trillo, Javier; Ferkin, Michael H


    Sperm competition occurs when 2 or more males copulate with a particular female during the same reproductive cycle, and their sperm compete to fertilize the female's available eggs. One strategy that male voles use to assess the risk and intensity of sperm competition involves responding to the presence of scent marks of conspecific males found near a sexually receptive female. Previously, we have shown that if a male vole copulated with a female while he was in the presence of the odors of another male he increased his sperm investment relative to his investment if another male's odors were not present. The aim of the present study was to test the hypothesis that males assess differences in the relative quality of competing males and adjust their sperm investment accordingly. We did so by allowing males to copulate when they were exposed to the scent mark of a 24-h food-deprived male (low-quality male) or the scent mark of a male that was not food deprived (high-quality male). The data indicate that male meadow voles did not increase their sperm investment during copulation when exposed to the scent mark of a food-deprived male but did so when they were exposed to the scent mark of a male that was not food deprived. The results support the hypothesis that male voles are able to adjust sperm investment when they encounter the scent marks of males that differ in quality.

  20. Trace metals in soil vegetation, and voles from mine land treated with sewage sludge

    Energy Technology Data Exchange (ETDEWEB)

    Alberici, T.M.; Sopper, W.E.; Storm, G.L.; Yahner, R.H.

    Trace-metal concentrations in soil, vegetation, and tissues of meadow voles (Microtus pennsylvanicus) were compared on a stripmined site reclaimed conventionally (control site) and with municipal sludge (treated site) in Somerset County, Pennsylvania, in March and April 1983. With the exception of Zn concentrations in birdsfoot trefoil (Lotus corniculatus L.), reclamation with municipal sludge did not increase trace metal concentrations in soil, vegetation, or meadow voles in comparison to the site reclaimed conventionally. Zinc concentration in birdsfoot trefoil from the site reclaimed with sludge was higher than that from the site reclaimed conventionally but was below phytotoxic levels. Concentrations of Cu, Zn, Co, Cd, and Ni in vole tissues were not significantly different between control and treated sites. However, Cr concentrations in kidney and bone and Pb concentrations in liver and bone were higher on the control site than on the treated site. Stomach analyses indicated that meadow voles preferred tall fescue (Festuca arundinaceae L.) and quackgrass (Agropyron repens L.) to birdsfoot trefoil and orchardgrass (Dactylis glomerata L.) 27 refs., 1 fig., 8 tabs.

  1. Laboratory model of adaptive radiation: a selection experiment in the bank vole. (United States)

    Sadowska, Edyta T; Baliga-Klimczyk, Katarzyna; Chrzaścik, Katarzyna M; Koteja, Paweł


    In a laboratory colony of a wild rodent, the bank vole Myodes (=Clethrionomys) glareolus, a multiway artificial selection experiment was applied to mimic evolution toward high aerobic metabolism achieved during locomotor activity, predatory behavior, and ability to cope with herbivorous diet. Four lines for each of the selection directions and four unselected control lines have been maintained. After three generations of within-family selection, the maximum rate of oxygen consumption achieved during swimming was 15% higher in the selected than in the control lines (least square means, adjusted for body mass: 252.0 vs. 218.6 mL O(2)/h, P = 0.0001). When fed a low-quality diet made of dried grass, voles from the lines selected for ability to cope with herbivorous diet lost about 0.7 g less mass than voles from the control lines (-2.44 vs. -3.16 g/4 d, P = 0.008). In lines selected for predatory behavior toward crickets, proportion of "predatory" individuals was higher than in the control lines (43.6% vs. 24.9%; P = 0.045), but "time to capture" calculated for the successful trials did not differ between the lines. The experiment continues, and the selected lines of voles will provide a unique model for testing hypotheses concerning correlated evolution of complex traits.

  2. Reproductive responses of male Brandt's voles ( Lasiopodomys brandtii) to 6-methoxybenzoxazolinone (6-MBOA) under short photoperiod (United States)

    Dai, Xin; Jiang, Lian Yu; Han, Mei; Ye, Man Hong; Wang, Ai Qin; Wei, Wan Hong; Yang, Sheng Mei


    The plant secondary metabolite 6-methoxybenzoxazolinone (6-MBOA) can stimulate and enhance animal reproduction. This compound has been successfully detected in Leymus chinensis, which is the main diet of Brandt's voles. The aim of this study was to investigate the effect of different 6-MBOA doses on the reproductive physiology of male Brandt's voles under a short photoperiod. The results showed that 6-MBOA administration increased relative testis weight, regardless of the dose, but it had little effect on the body mass. Low and middle doses of 6-MBOA increased the concentrations of luteinizing hormone and testosterone in the serum and the mRNA levels of StAR and CYP11a1 in the testes. However, 6-MBOA did not cause any significant increase in the mRNA levels of KiSS-1, GPR54, and GnRH compared to those in the control group. The mRNA level of KiSS-1 in the arcuate nucleus (ARC) was higher than that in the anteroventral periventricular nucleus (AVPV). Collectively, our results demonstrated that the number of KiSS-1-expressing neurons located in the ARC was the highest, and that 6-MBOA, which might modulate the reproductive activity along the hypothalamic-pituitary-gonadal axis, had a dose-dependent stimulatory effect on the reproductive activity of Brandt's voles under a short photoperiod. Our study provided insights into the mechanism of 6-MBOA action and the factors influencing the onset of reproduction in Brandt's voles.

  3. Spontaneous expression of magnetic compass orientation in an epigeic rodent: the bank vole, Clethrionomys glareolus (United States)

    Oliveriusová, Ludmila; Němec, Pavel; Pavelková, Zuzana; Sedláček, František


    Magnetoreception has been convincingly demonstrated in only a few mammalian species. Among rodents, magnetic compass orientation has been documented in four species of subterranean mole rats and two epigeic (i.e. active above ground) species—the Siberian hamster and the C57BL/6J mouse. The mole rats use the magnetic field azimuth to determine compass heading; their directional preference is spontaneous and unimodal, and their magnetic compass is magnetite-mediated. By contrast, the primary component of orientation response is learned in the hamster and the mouse, but both species also exhibit a weak spontaneous bimodal preference in the natural magnetic field. To determine whether the magnetic compass of wild epigeic rodents features the same functional properties as that of laboratory rodents, we investigated magnetic compass orientation in the bank vole Clethrionomys glareolus (Cricetidae, Rodentia). The voles exhibited a robust spontaneous bimodal directional preference, i.e. built nests and slept preferentially along the north-south axis, and deflected their directional preference according to a shift in the direction of magnetic north, clearly indicating that they were deriving directional information from the magnetic field. Thus, bimodal, axially symmetrical directional choice seems to be a common feature shared by epigeic rodents. However, spontaneous directional preference in the bank vole appeared to be more pronounced than that reported in the hamster and the mouse. These findings suggest that bank voles are well suited for future studies investigating the adaptive significance and mechanisms of magnetic orientation in epigeic rodents.

  4. FGF4 independent derivation of trophoblast stem cells from the common vole.

    Directory of Open Access Journals (Sweden)

    Elena V Grigor'eva

    Full Text Available The derivation of stable multipotent trophoblast stem (TS cell lines from preimplantation, and early postimplantation mouse embryos has been reported previously. FGF4, and its receptor FGFR2, have been identified as embryonic signaling factors responsible for the maintenance of the undifferentiated state of multipotent TS cells. Here we report the derivation of stable TS-like cell lines from the vole M. rossiaemeridionalis, in the absence of FGF4 and heparin. Vole TS-like cells are similar to murine TS cells with respect to their morphology, transcription factor gene expression and differentiation in vitro into derivatives of the trophectoderm lineage, and with respect to their ability to invade and erode host tissues, forming haemorrhagic tumours after subcutaneous injection into nude mice. Moreover, vole TS-like cells carry an inactive paternal X chromosome, indicating that they have undergone imprinted X inactivation, which is characteristic of the trophoblast lineage. Our results indicate that an alternative signaling pathway may be responsible for the establishment and stable proliferation of vole TS-like cells.

  5. Effects of vole fluctuations on the population dynamics of the barn owl Tyto alba

    NARCIS (Netherlands)

    Klok, T.C.; Roos, A.M.


    Many predator species feed on prey that fluctuates in abundance from year to year. Birds of prey can face large fluctuations in food abundance i.e. small mammals, especially voles. These annual changes in prey abundance strongly affect the reproductive success and mortality of the individual predato

  6. Puumala hantavirus infections in bank vole populations: host and virus dynamics in Central Europe. (United States)

    Reil, Daniela; Rosenfeld, Ulrike M; Imholt, Christian; Schmidt, Sabrina; Ulrich, Rainer G; Eccard, Jana A; Jacob, Jens


    In Europe, bank voles (Myodes glareolus) are widely distributed and can transmit Puumala virus (PUUV) to humans, which causes a mild to moderate form of haemorrhagic fever with renal syndrome, called nephropathia epidemica. Uncovering the link between host and virus dynamics can help to prevent human PUUV infections in the future. Bank voles were live trapped three times a year in 2010-2013 in three woodland plots in each of four regions in Germany. Bank vole population density was estimated and blood samples collected to detect PUUV specific antibodies. We demonstrated that fluctuation of PUUV seroprevalence is dependent not only on multi-annual but also on seasonal dynamics of rodent host abundance. Moreover, PUUV infection might affect host fitness, because seropositive individuals survived better from spring to summer than uninfected bank voles. Individual space use was independent of PUUV infections. Our study provides robust estimations of relevant patterns and processes of the dynamics of PUUV and its rodent host in Central Europe, which are highly important for the future development of predictive models for human hantavirus infection risk.

  7. Introgression of mitochondrial DNA among Myodes voles: consequences for energetics?

    Directory of Open Access Journals (Sweden)

    Boratyński Zbyszek


    Full Text Available Abstract Background Introgression of mitochondrial DNA (mtDNA is among the most frequently described cases of reticulate evolution. The tendency of mtDNA to cross interspecific barriers is somewhat counter-intuitive considering the key function of enzymes that it encodes in the oxidative-phosphorylation process, which could give rise to hybrid dysfunction. How mtDNA reticulation affects the evolution of metabolic functions is, however, uncertain. Here we investigated how morpho-physiological traits vary in natural populations of a common rodent (the bank vole, Myodes glareolus and whether this variation could be associated with mtDNA introgression. First, we confirmed that M. glareolus harbour mtDNA introgressed from M. rutilus by analyzing mtDNA (cytochrome b, 954 bp and nuclear DNA (four markers; 2333 bp in total sequence variation and reconstructing loci phylogenies among six natural populations in Finland. We then studied geographic variation in body size and basal metabolic rate (BMR among the populations of M. glareolus and tested its relationship with mtDNA type. Results Myodes glareolus and its arctic neighbour, M. rutilus, are reciprocally monophyletic at the analyzed nuclear DNA loci. In contrast, the two northernmost populations of M. glareolus have a fixed mitotype that is shared with M. rutilus, likely due to introgressive hybridization. The analyses of phenotypic traits revealed that the body mass and whole-body, but not mass corrected, BMR are significantly reduced in M. glareolus females from northern Finland that also have the introgressed mitotype. Restricting the analysis to the single population where the mitotypes coexist, the association of mtDNA type with whole-body BMR remained but those with mass corrected BMR and body mass did not. Mitochondrial sequence variation in the introgressed haplotypes is compatible with demographic growth of the populations, but may also be a result of positive selection. Conclusion Our

  8. Analysis of internal doses to Mole voles inhabiting the East-Ural radioactive trace

    Energy Technology Data Exchange (ETDEWEB)

    Malinovsky, G.; Yarmoshenko, I. [Institute of Industrial Ecology UB RAS (Russian Federation); Chibiryak, M.; Vasil' ev, A. [Institute of Plant and Animal Ecology UB RAS (Russian Federation)


    Substantial task of development of approaches to radiation protection of non-human biota is investigation of relationships of exposure to dose, and dose to effects. Small mammals inhabiting territory of the East-Ural Radioactive Trace (EURT) are affected to ionizing radiation for many generations after accident at Mayak plutonium production in 1957. According to results of numerous studies a number of effects of exposure are observed. It is remarkable that the revealed effects are both negative and adaptive. In particular, the analysis of the variability of morphological structures of the axial skull and lower jaw in the population of northern mole vole (Ellobius talpinus Pall.), the burrowing rodent inhabiting the EURT, is of great interest. At the same time there is no reliable assessment of the radiation doses to these animals. Earlier we developed the approach to assess internal doses to mouse-like rodents (mice and voles) caused by incorporated {sup 90}Sr, which is the main dose contributing radionuclide at the EURT. Dose assessments are based on the results of beta-radiometry of intact bone. Routine methods for measuring the activity concentration of {sup 90}Sr in skeleton require ashing of samples, however in morphometric studies the destruction of material should be avoided: the skulls of mole voles are stored in the environmental samples depository of IPAE. Coefficients linking results of beta-radiometry of intact bone and activity concentration of {sup 90}Sr in skull of mouse was obtained basing on comparison of results of beta-radiometry of intact bone and bone ash. Obtained coefficients cannot be directly applied for calculating activity concentration of {sup 90}Sr in mole vole skulls because they are significantly larger. Therefore the additional study is required to assess proper coefficient of conversion from beta-radiometry to activity concentration of {sup 90}Sr. Developed dose assessment procedure includes application of the published values of

  9. Landscape features and helminth co-infection shape bank vole immunoheterogeneity, with consequences for Puumala virus epidemiology. (United States)

    Guivier, E; Galan, M; Henttonen, H; Cosson, J-F; Charbonnel, N


    Heterogeneity in environmental conditions helps to maintain genetic and phenotypic diversity in ecosystems. As such, it may explain why the capacity of animals to mount immune responses is highly variable. The quality of habitat patches, in terms of resources, parasitism, predation and habitat fragmentation may, for example, trigger trade-offs ultimately affecting the investment of individuals in various immunological pathways. We described spatial immunoheterogeneity in bank vole populations with respect to landscape features and co-infection. We focused on the consequences of this heterogeneity for the risk of Puumala hantavirus (PUUV) infection. We assessed the expression of the Tnf-α and Mx2 genes and demonstrated a negative correlation between PUUV load and the expression of these immune genes in bank voles. Habitat heterogeneity was partly associated with differences in the expression of these genes. Levels of Mx2 were lower in large forests than in fragmented forests, possibly due to differences in parasite communities. We previously highlighted the positive association between infection with Heligmosomum mixtum and infection with PUUV. We found that Tnf-α was more strongly expressed in voles infected with PUUV than in uninfected voles or in voles co-infected with the nematode H. mixtum and PUUV. H. mixtum may limit the capacity of the vole to develop proinflammatory responses. This effect may increase the risk of PUUV infection and replication in host cells. Overall, our results suggest that close interactions between landscape features, co-infection and immune gene expression may shape PUUV epidemiology.

  10. Hierarchical Bayesian spatial models for multispecies conservation planning and monitoring. (United States)

    Carroll, Carlos; Johnson, Devin S; Dunk, Jeffrey R; Zielinski, William J


    Biologists who develop and apply habitat models are often familiar with the statistical challenges posed by their data's spatial structure but are unsure of whether the use of complex spatial models will increase the utility of model results in planning. We compared the relative performance of nonspatial and hierarchical Bayesian spatial models for three vertebrate and invertebrate taxa of conservation concern (Church's sideband snails [Monadenia churchi], red tree voles [Arborimus longicaudus], and Pacific fishers [Martes pennanti pacifica]) that provide examples of a range of distributional extents and dispersal abilities. We used presence-absence data derived from regional monitoring programs to develop models with both landscape and site-level environmental covariates. We used Markov chain Monte Carlo algorithms and a conditional autoregressive or intrinsic conditional autoregressive model framework to fit spatial models. The fit of Bayesian spatial models was between 35 and 55% better than the fit of nonspatial analogue models. Bayesian spatial models outperformed analogous models developed with maximum entropy (Maxent) methods. Although the best spatial and nonspatial models included similar environmental variables, spatial models provided estimates of residual spatial effects that suggested how ecological processes might structure distribution patterns. Spatial models built from presence-absence data improved fit most for localized endemic species with ranges constrained by poorly known biogeographic factors and for widely distributed species suspected to be strongly affected by unmeasured environmental variables or population processes. By treating spatial effects as a variable of interest rather than a nuisance, hierarchical Bayesian spatial models, especially when they are based on a common broad-scale spatial lattice (here the national Forest Inventory and Analysis grid of 24 km(2) hexagons), can increase the relevance of habitat models to multispecies

  11. Implantation and early postimplantation development of the bank vole Clethrionomys glareolus, Schreber. (United States)

    Ozdzeński, W; Mystkowska, E T


    The development of the bank vole Clethrionomys glareolus is described from implantation to the formation of the foetal membranes. The embryonic development of this species combines features of primitive rodent species, for example Geomys bursarius and highly specialized ones, for examples Mus musculus. The egg-cylinder is formed by invagination into the blastocoelic cavity of the inner cell mass and polar trophoblast overlying it; this resembles in many respects the early stages of development of primitive species. The fully formed egg-cylinder, however, resembles that of the mouse and the formation of foetal membranes is also similar to that in Muridae. It is concluded that in the bank vole and also in other rodents, the extra-embryonic ectoderm of the egg-cylinder is derived from the polar trophoblast rather than from the inner cell mass.

  12. [Blood system peculiarities in the bank vole (Clethrionomys glareolus) under chronic environmental pollution]. (United States)

    Tarakhtiĭ, É A; Mukhacheva, S V


    The parameters of peripheral blood and hemopoietic organs in mature and immature bank voles inhabiting a chemically polluted area were studied. Variability of the blood system parameters depending on the level of toxic load and the animals' reproductive status was determined. Alteration of the cell composition of erythrocytes and leucocytes, the structure of erythrocytes, and the hemoglobin fractions and leucocyte functions describe the adaptive response to the factors of a changed environment more than the concentration of leucocytes, erythrocytes, and blood hemoglobin.

  13. Female prairie vole mate-choice is affected by the males' birth litter composition. (United States)

    Curtis, J Thomas


    Experimental testing and retrospective examination of breeding records were used to examine the influence of sex composition and/or size of males' birth litters on female mate-choice. Sexually naïve female prairie voles (Microtus ochrogaster) avoided males derived from all-male litters, but showed no preference for, or aversion to, males from single-male litters or from more typical mixed-sex litters. Examination of the pregnancy status of females after two weeks of pairing with a male allowed us to estimate the probabilites of a pups' intrauterine position relative to siblings for various litter sizes. The typical prairie vole pup derived from a mixed-sex litter comprised of 4.4 pups, and had a 13% chance of being isolated from siblings in utero and a 22% chance of being between siblings in utero. Pups from single-sex litters tended to be larger at weaning than did pups from mixed-sex litters; however, male size did not influence female choice behavior. These results suggest that some aspect of the perinatal experience of prairie vole pups from single sex litters can influence social interactions later in life.

  14. [Helminth fauna of the bank vole myodes glareolus (Schreber, 1780) in the Kizhi Archipelago]. (United States)

    Bugmyrin, S V; Korosov, A V; Bespyatova, L A; Ieshko, E P


    The present study was aimed to examine the specific features of the helminth fauna in insular populations of the bank vole (Myodes glareolus) in the north of the species range. The material was collected in and nearby the Kizhi Archipelago (Lake Onega, 62°1' N 35°12' E) during August 1997, 2005-2007, 2012 and 2013. Small mammals were trapped on 23 islands (varying from 2 to 15,000 ha) and on the mainland. Helminthological met- hods were applied to examine 301 specimens of M glareolus. Fourteen helminth species were found: trematodes--Skrjabinoplagiorchis vigisi; cestodes--Paranoplocephala omphalodes, P. gracilis, Catenotaenia henttoneni, Taenia mustelae, Cladotaenia globife- ra, Spirometra erinacei; nematodes--Trichocephalus muris, Aonchotheca murissylvatici, Hepaticola hepatica, Heligmosomum mixtum, Heligmosomoides glareoli, Longistriata minuta, Syphacia petrusewiczi. The parasites S. vigisi, S. erinaci, H. hepatica and T. muris were identified in the bank vole in Karelia for the first time. Significant differences were detected between the helminth faunas of local insular populations of the bank vole. A distinctive feature of all small islands was that samples from them lacked the widespread pa- rasitic nematode Heligmosomum mixtum. The studies have confirmed the general trends observed in the parasite fauna of most isolated populations of small mammals: a poorer species diversity and high infestation rates with certain species of parasites. The Kizhi Archipelago is characterized by the specific high abundance of regionally rare parasite species (H hepatica, A. murissylvatici), and by the absence of common parasites (H. mixtum, H. glareoli).

  15. Adaptive evolution during an ongoing range expansion: the invasive bank vole (Myodes glareolus) in Ireland. (United States)

    White, Thomas A; Perkins, Sarah E; Heckel, Gerald; Searle, Jeremy B


    Range expansions are extremely common, but have only recently begun to attract attention in terms of their genetic consequences. As populations expand, demes at the wave front experience strong genetic drift, which is expected to reduce genetic diversity and potentially cause 'allele surfing', where alleles may become fixed over a wide geographical area even if their effects are deleterious. Previous simulation models show that range expansions can generate very strong selective gradients on dispersal, reproduction, competition and immunity. To investigate the effects of range expansion on genetic diversity and adaptation, we studied the population genomics of the bank vole (Myodes glareolus) in Ireland. The bank vole was likely introduced in the late 1920s and is expanding its range at a rate of ~2.5 km/year. Using genotyping-by-sequencing, we genotyped 281 bank voles at 5979 SNP loci. Fourteen sample sites were arranged in three transects running from the introduction site to the wave front of the expansion. We found significant declines in genetic diversity along all three transects. However, there was no evidence that sites at the wave front had accumulated more deleterious mutations. We looked for outlier loci with strong correlations between allele frequency and distance from the introduction site, where the direction of correlation was the same in all three transects. Amongst these outliers, we found significant enrichment for genic SNPs, suggesting the action of selection. Candidates for selection included several genes with immunological functions and several genes that could influence behaviour.

  16. Validation of the Puumala virus rapid field test for bank voles in Germany. (United States)

    Reil, D; Imholt, C; Rosenfeld, U M; Drewes, S; Fischer, S; Heuser, E; Petraityte-Burneikiene, R; Ulrich, R G; Jacob, J


    Puumala virus (PUUV) causes many human infections in large parts of Europe and can lead to mild to moderate disease. The bank vole (Myodes glareolus) is the only reservoir of PUUV in Central Europe. A commercial PUUV rapid field test for rodents was validated for bank-vole blood samples collected in two PUUV-endemic regions in Germany (North Rhine-Westphalia and Baden-Württemberg). A comparison of the results of the rapid field test and standard ELISAs indicated a test efficacy of 93-95%, largely independent of the origin of the antigens used in the ELISA. In ELISAs, reactivity for the German PUUV strain was higher compared to the Swedish strain but not compared to the Finnish strain, which was used for the rapid field test. In conclusion, the use of the rapid field test can facilitate short-term estimation of PUUV seroprevalence in bank-vole populations in Germany and can aid in assessing human PUUV infection risk.

  17. Reproductive potential of a vole pest (Arvicola scherman in Spanish apple orchards

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    Aitor Somoano


    Full Text Available Fossorial water voles, Arvicola scherman, feed on tree roots causing important damages in European apple orchards. Since the intensity of crop damage produced by rodents ultimately depends on their inherent capacity to increase their population, the main goal of this study was to determine the reproductive potential of the subspecies A. scherman cantabriae in apple orchards from Asturias (NW Spain, where voles breed over the whole year. Our results were compared with those reported for the subspecies A. scherman monticola from the Spanish Pyrenees (where reproduction ceases in winter. Sexual characteristics, body condition, relative age class and number of embryos were recorded from 422 females caught in apple orchards along two years. We found pregnant females all along the year, which were able to produce a high number of litters per year (7.30 although litter size was relatively moderate (first year: 3.87 embryos/female; second year: 3.63 embryos/females. The potential number of pups per female and year (first year: 28.25; second year: 26.50 was substantially higher than that reported for Pyrenean voles, what is probably related with differences in the length of the breeding season and in life histories between subspecies. In our population, the number of implanted embryos correlated positively with the body condition of the mother. Our results reveal that management efforts should not be seasonal as they used to be so far and invite to explore the physiological consequences of management practices.

  18. A Study of Changes in Uterine Leucocytes During Early Pregnancy in the Mouse-vole Interspesific Pregnancies

    Institute of Scientific and Technical Information of China (English)

    Diah Tri Widayati; Tatsuya Tada; Naoko Inoue


    Mouse and vole embryos were allogeneically and xenogeneically transferred into pseudopregnant CD.1 and immunodeficient (seid)female mice,and we investigated the distribution of uterine leucocytes cells in the implantation sites on days 5,6,and 7 of pregnancy. Maerophages were evenly distributed in the endometrium on days 5-7.Neutrophils were rarely seen on days 5-7,but lymphocytes were found throughout the endometrium,often in groups associated with glands or the luminal epithelium.The number of uNK cells increased markedly at the mesometrial uriangle and the outer decidual area in the CD-1 uteri containing vole embryos;by contrast,seid uteri having vole embryos showed almost the same number as those having mouse embryos.Mast cells were present in large numbers at the myometrium,but rarely in the decidua in all types of pregnant uteri.Cells at the myometrium were more numerous in xenogeneic than in allogeneic transfer.Maay mast cells appeared in the inner decidua where xenogeneically transferred vole embryos were dead and aborted.These results suggest the possibility that uterine leucocytes mediate various immunological events in the mouse-vole interspesific pregnancies.

  19. Dopamine D2 receptors in the nucleus accumbens are important for social attachment in female prairie voles (Microtus ochrogaster). (United States)

    Gingrich, B; Liu, Y; Cascio, C; Wang, Z; Insel, T R


    The prairie vole (Microtus ochrogaster), a monogamous rodent that forms long-lasting pair bonds, has proven useful for the neurobiological study of social attachment. In the laboratory, pair bonds can be assessed by testing for a partner preference, a choice test in which pair-bonded voles regularly prefer their partner to a conspecific stranger. Studies reported here investigate the role of dopamine D2-like receptors (i.e., D2, D3, and D4 receptors) in the nucleus accumbens (NAcc) for the formation of a partner preference in female voles. Mating facilitated partner preference formation and associated with an approximately 50% increase in extracellular dopamine in the NAcc. Microinjection of the D2 antagonist eticlopride into the NAcc (but not the prelimbic cortex) blocked the formation of a partner preference in mating voles, whereas the D2 agonist quinpirole facilitated formation of a partner preference in the absence of mating. Taken together, these results suggest that D2-like receptors in the NAcc are important for the mediation of social attachments in female voles.

  20. Explaining bank vole cycles in southern Norway 1980-2004 from bilberry reports 1932-1977 and climate. (United States)

    Selås, Vidar


    Correlations between mast fruiting of bilberry Vaccinium myrtillus and peak levels of Clethrionomys-voles have been reported from both Norway and Finland, but there has been a discussion whether this is a bottom-up or a top-down relationship. In a multiple regression model, 65% of the variation in a bilberry production index calculated from game reports from southern Norway 1932-1977 could be explained by the berry index of the two preceding years and climate factors acting during key stages of the flowering cycle. High vole populations in previous years did not contribute to explain the fluctuation in berry production. I used the selected model and climate data to predict bilberry production for the period 1978-2004. Predicted berry indices of the current and previous year explained 38% and the total amount of precipitation in May-June explained 16% of the variation in a log-transformed snap-trapping index of bank vole Clethrionomys glareolus 1980-2004. The vole index was not related to any of the climate variables used to predict berry production. This pattern supports the hypothesis that vole cycles are generated by changes in plant chemistry due to climate-synchronized mast fruiting.

  1. [Ecological aspects of infection of bank vole Clethrionomys glareolus (Schreber, 1780) with Trypanosoma (Herpetosoma) evotomys Hadwen, 1912]. (United States)

    Karbowiak, G; Wita, I


    The studies were carried out in Kosewo Górne in the Mazurian District (North-East region of Poland), in September 1995, September 1996 and between May 1997 and June 1998 each month. The animals were trapped in live traps, and after study they were marked and released. The infection of trypanosomes was detected using microhaematocrit centrifugation technique and in blood smears. The intensity of infection had the range from 50 to 150 000 individuals in 1 ml of blood. The maximal prevalence of infection was in August and September and there were 45% and 38% of infected voles respectively. The infection was detected also in May 1998, in other months the prevalence had low level. There were no individuals of bank vole infected in succeeding months. The females of bank vole are more often infected with trypanosomes than males.

  2. Induced Pluripotent Stem Cells With Six Reprogramming Factors From Prairie Vole, Which Is an Animal Model for Social Behaviors. (United States)

    Katayama, Masafumi; Hirayama, Takashi; Horie, Kengo; Kiyono, Tohru; Donai, Kenichiro; Takeda, Satoru; Nishimori, Katsuhiko; Fukuda, Tomokazu


    Prairie voles show strong pair bonding with their mating partners, and they demonstrate parental behavior toward their infants, indicating that the prairie vole is a unique animal model for analysis of molecular mechanisms of social behavior. Until a recent study, the signaling pathway of oxytocin was thought to be critical for the social behavior of prairie voles, but neuron-specific functional research may be necessary to identify the molecular mechanisms of social behavior. Prairie vole pluripotent stem cells of high quality are essential to elucidate the molecular mechanisms of social behaviors. Generation of high-quality induced pluripotent stem cells (iPSCs) would help to establish a genetically modified prairie vole, including knockout and knock-in models, based on the pluripotency of iPSCs. Thus, we attempted to establish high-quality prairie vole-derived iPSCs (pv-iPSCs) in this study. We constructed a polycistronic reprogramming vector, which included six reprograming factors (Oct3/4, Sox2, Klf4, c-myc, Lin28, and Nanog). Furthermore, we evaluated the effect of six reprogramming factors, which included Oct3/4 with the transactivation domain (TAD) of MyoD. Implantation of the pv-iPSCs into immunodeficient mice caused a teratoma with three germ layers. Furthermore, the established pv-iPSCs tested positive for stem cell markers, including alkaline phosphatase activity (ALP), stage-specific embryonic antigen (SSEA)-1, and dependence on leukemia inhibitory factor (LIF). Our data indicate that our newly established pv-iPSCs may be a useful tool for genetic analysis of social behavior.

  3. Molecular characterization of hypoxia and hypoxia-inducible factor 1 alpha (HIF-1α) from Taiwan voles (Microtus kikuchii). (United States)

    Jiang, Yi-Fan; Chou, Chung-Hsi; Lin, En-Chung; Chiu, Chih-Hsien


    Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that senses and adapts cells to hypoxic environmental conditions. HIF-1 is composed of an oxygen-regulated α subunit (HIF-1α) and a constitutively expressed β subunit (HIF-1β). Taiwan voles (Microtus kikuchii) are an endemic species in Taiwan, found only in mountainous areas greater than 2000m above sea level. In this study, the full-length HIF-1α cDNA was cloned and sequenced from liver tissues of Taiwan voles. We found that HIF-1α of Taiwan voles had high sequence similarity to HIF-1α of other species. Sequence alignment of HIF-1α functional domains indicated basic helix-loop-helix (bHLH), PER-ARNT-SIM (PAS) and C-terminal transactivation (TAD-C) domains were conserved among species, but sequence variations were found between the oxygen-dependent degradation domains (ODDD). To measure Taiwan vole HIF-1α responses to hypoxia, animals were challenged with cobalt chloride, and HIF-1α mRNA and protein expression in brain, lung, heart, liver, kidney, and muscle was assessed by quantitative RT-PCR and Western blot analysis. Upon induction of hypoxic stress with cobalt chloride, an increase in HIF-1α mRNA levels was detected in lung, heart, kidney, and muscle tissue. In contrast, protein expression levels showed greater variation between individual animals. These results suggest that the regulation of HIF-1α may be important to the Taiwan vole under cobalt chloride treatments. But more details regarding the evolutionary effect of environmental pressure on HIF-1α primary sequence, HIF-1α function and regulation in Taiwan voles remain to be identified.

  4. The importance of bank vole density and rainy winters in predicting nephropathia epidemica incidence in Northern Sweden.

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    Hussein Khalil

    Full Text Available Pathogenic hantaviruses (family Bunyaviridae, genus Hantavirus are rodent-borne viruses causing hemorrhagic fever with renal syndrome (HFRS in Eurasia. In Europe, there are more than 10,000 yearly cases of nephropathia epidemica (NE, a mild form of HFRS caused by Puumala virus (PUUV. The common and widely distributed bank vole (Myodes glareolus is the host of PUUV. In this study, we aim to explain and predict NE incidence in boreal Sweden using bank vole densities. We tested whether the number of rainy days in winter contributed to variation in NE incidence. We forecast NE incidence in July 2013-June 2014 using projected autumn vole density, and then considering two climatic scenarios: 1 rain-free winter and 2 winter with many rainy days. Autumn vole density was a strong explanatory variable of NE incidence in boreal Sweden in 1990-2012 (R2 = 79%, p<0.001. Adding the number of rainy winter days improved the model (R2 = 84%, p<0.05. We report for the first time that risk of NE is higher in winters with many rainy days. Rain on snow and ground icing may block vole access to subnivean space. Seeking refuge from adverse conditions and shelter from predators, voles may infest buildings, increasing infection risk. In a rainy winter scenario, we predicted 812 NE cases in boreal Sweden, triple the number of cases predicted in a rain-free winter in 2013/2014. Our model enables identification of high risk years when preparedness in the public health sector is crucial, as a rainy winter would accentuate risk.

  5. Successive sheep grazing reduces population density of Brandt's voles in steppe grassland by altering food resources: a large manipulative experiment. (United States)

    Li, Guoliang; Yin, Baofa; Wan, Xinrong; Wei, Wanhong; Wang, Guiming; Krebs, Charles J; Zhang, Zhibin


    Livestock grazing has shaped grassland ecosystems around the world. Previous studies indicated grazing showed various impacts on small rodents; however, most studies were conducted over 1-2 years without controlling for confounding factors such as immigration/emigration and predation in rodents. Brandt's voles (Lasiopodomys brandtii) are generally recognized as pests because of food overlap with domestic herbivores, but are also important for biodiversity conservation because they provide nests or food to many birds. Fully understanding the ecological relationship between domestic herbivores and small mammals is essential to making ecosystem management decisions. To address these needs, we carried out a field experiment during the period 2010-2013 to assess the effects of sheep grazing on vegetation and the population density of Brandt's voles along a gradient of three grazing intensities by using 12 large-scale enclosures. Responses of Brandt's voles to livestock grazing varied with grazing intensity and year. As compared to the control group, sheep grazing had no effect on vole abundance in the first year but an overall negative effect on vole abundance in the following 3 years. Successive grazing caused decreases in survival and male body mass of voles, but had no significant effect on fecundity. Negative effects of grazing were associated with a grazing-induced deterioration in both food quantity (reflected by biomass and cover of less-preferred plants), and food quality (measured by tannin and total phenol content). Our findings highlight the urgent need for more flexible management of yearly rotational grazing to optimize livestock production while maintaining species diversity and ecosystem health.

  6. Intracerebral Borna disease virus infection of bank voles leading to peripheral spread and reverse transcription of viral RNA.

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    Paula Maria Kinnunen

    Full Text Available Bornaviruses, which chronically infect many species, can cause severe neurological diseases in some animal species; their association with human neuropsychiatric disorders is, however, debatable. The epidemiology of Borna disease virus (BDV, as for other members of the family Bornaviridae, is largely unknown, although evidence exists for a reservoir in small mammals, for example bank voles (Myodes glareolus. In addition to the current exogenous infections and despite the fact that bornaviruses have an RNA genome, bornavirus sequences integrated into the genomes of several vertebrates millions of years ago. Our hypothesis is that the bank vole, a common wild rodent species in traditional BDV-endemic areas, can serve as a viral host; we therefore explored whether this species can be infected with BDV, and if so, how the virus spreads and whether viral RNA is transcribed into DNA in vivo.We infected neonate bank voles intracerebrally with BDV and euthanized them 2 to 8 weeks post-infection. Specific Ig antibodies were detectable in 41%. Histological evaluation revealed no significant pathological alterations, but BDV RNA and antigen were detectable in all infected brains. Immunohistology demonstrated centrifugal spread throughout the nervous tissue, because viral antigen was widespread in peripheral nerves and ganglia, including the mediastinum, esophagus, and urinary bladder. This was associated with viral shedding in feces, of which 54% were BDV RNA-positive, and urine at 17%. BDV nucleocapsid gene DNA occurred in 66% of the infected voles, and, surprisingly, occasionally also phosphoprotein DNA. Thus, intracerebral BDV infection of bank vole led to systemic infection of the nervous tissue and viral excretion, as well as frequent reverse transcription of the BDV genome, enabling genomic integration. This first experimental bornavirus infection in wild mammals confirms the recent findings regarding bornavirus DNA, and suggests that bank voles are

  7. Intracerebral Borna disease virus infection of bank voles leading to peripheral spread and reverse transcription of viral RNA. (United States)

    Kinnunen, Paula Maria; Inkeroinen, Hanna; Ilander, Mette; Kallio, Eva Riikka; Heikkilä, Henna Pauliina; Koskela, Esa; Mappes, Tapio; Palva, Airi; Vaheri, Antti; Kipar, Anja; Vapalahti, Olli


    Bornaviruses, which chronically infect many species, can cause severe neurological diseases in some animal species; their association with human neuropsychiatric disorders is, however, debatable. The epidemiology of Borna disease virus (BDV), as for other members of the family Bornaviridae, is largely unknown, although evidence exists for a reservoir in small mammals, for example bank voles (Myodes glareolus). In addition to the current exogenous infections and despite the fact that bornaviruses have an RNA genome, bornavirus sequences integrated into the genomes of several vertebrates millions of years ago. Our hypothesis is that the bank vole, a common wild rodent species in traditional BDV-endemic areas, can serve as a viral host; we therefore explored whether this species can be infected with BDV, and if so, how the virus spreads and whether viral RNA is transcribed into DNA in vivo.We infected neonate bank voles intracerebrally with BDV and euthanized them 2 to 8 weeks post-infection. Specific Ig antibodies were detectable in 41%. Histological evaluation revealed no significant pathological alterations, but BDV RNA and antigen were detectable in all infected brains. Immunohistology demonstrated centrifugal spread throughout the nervous tissue, because viral antigen was widespread in peripheral nerves and ganglia, including the mediastinum, esophagus, and urinary bladder. This was associated with viral shedding in feces, of which 54% were BDV RNA-positive, and urine at 17%. BDV nucleocapsid gene DNA occurred in 66% of the infected voles, and, surprisingly, occasionally also phosphoprotein DNA. Thus, intracerebral BDV infection of bank vole led to systemic infection of the nervous tissue and viral excretion, as well as frequent reverse transcription of the BDV genome, enabling genomic integration. This first experimental bornavirus infection in wild mammals confirms the recent findings regarding bornavirus DNA, and suggests that bank voles are capable of

  8. Effects of neonatal paternal deprivation or early deprivation on anxiety and social behaviors of the adults in mandarin voles. (United States)

    Jia, Rui; Tai, Fadao; An, Shucheng; Zhang, Xia; Broders, Hugh


    This study examined whether neonatal paternal deprivation (PD: father was removed and pups were raised just by mother) or early deprivation (ED: pups were raised by both parents except separated from not only the dam but also the peers for three hours a day from PND 0 to 13) has long-term effects on anxiety and social behaviors of adult mandarin voles. Newborn mandarin voles of F2 generation were randomly assigned to one of three groups: bi-parental care (PC: pups were raised by both parents), PD and ED. The parental care behaviors of F1 generation were observed at the age of 0, 13 and 21 days (PND 0, 13, 21) of F2 generation of PC and PD groups. Moreover, each mandarin vole of F2 generation received an open field test and a social interaction test on PND 70 and PND 75, respectively. No significant differences of parental behavior were observed between mothers and fathers from PC families, showing typical parental behavior of socially monogamous rodents. In addition, no significant differences of maternal behaviors were found between mothers from PC and PD families, indicating no maternal compensation towards pups for the absence of the paternal care. In the open field test, mandarin voles from both PD and ED families displayed higher levels of anxiety and lower locomotor activity, relative to offspring of PC family. In the social interaction test, both PD and ED mandarin voles also showed lower levels of social behavior and higher levels of anxiety. Thus, both PD and ED significantly increase anxiety and reduce social behavior of adult mandarin voles, suggesting that variation in parental investment may lead to variation in anxiety and social behaviors in rodents with different mating systems.

  9. The importance of bank vole density and rainy winters in predicting nephropathia epidemica incidence in Northern Sweden. (United States)

    Khalil, Hussein; Olsson, Gert; Ecke, Frauke; Evander, Magnus; Hjertqvist, Marika; Magnusson, Magnus; Löfvenius, Mikaell Ottosson; Hörnfeldt, Birger


    Pathogenic hantaviruses (family Bunyaviridae, genus Hantavirus) are rodent-borne viruses causing hemorrhagic fever with renal syndrome (HFRS) in Eurasia. In Europe, there are more than 10,000 yearly cases of nephropathia epidemica (NE), a mild form of HFRS caused by Puumala virus (PUUV). The common and widely distributed bank vole (Myodes glareolus) is the host of PUUV. In this study, we aim to explain and predict NE incidence in boreal Sweden using bank vole densities. We tested whether the number of rainy days in winter contributed to variation in NE incidence. We forecast NE incidence in July 2013-June 2014 using projected autumn vole density, and then considering two climatic scenarios: 1) rain-free winter and 2) winter with many rainy days. Autumn vole density was a strong explanatory variable of NE incidence in boreal Sweden in 1990-2012 (R2 = 79%, p<0.001). Adding the number of rainy winter days improved the model (R2 = 84%, p<0.05). We report for the first time that risk of NE is higher in winters with many rainy days. Rain on snow and ground icing may block vole access to subnivean space. Seeking refuge from adverse conditions and shelter from predators, voles may infest buildings, increasing infection risk. In a rainy winter scenario, we predicted 812 NE cases in boreal Sweden, triple the number of cases predicted in a rain-free winter in 2013/2014. Our model enables identification of high risk years when preparedness in the public health sector is crucial, as a rainy winter would accentuate risk.

  10. Self-grooming induced by sexual chemical signals in male root voles (Microtus oeconomus Pallas). (United States)

    Yu, Honghao; Yue, Pengpeng; Sun, Ping; Zhao, Xinquan


    Sniffing is one-way animals collect chemical signals, and many males self-groom when they encounter the odor of opposite-sex conspecifics. We tested the hypothesis that sexual chemical signals from females can induce self-grooming behavior in male root voles (Microtus oeconomus Pallas). Specifically, we investigated the sniffing pattern of male root voles in response to odors from the head, trunk, and tail areas of lactating and non-lactating females. The self-grooming behavior of males in response to female individual odorant stimuli was documented, and the relationship between self-grooming and sniffing of odors from the head, trunk, and tails areas were analyzed. Sniffing pattern results showed that males are most interested in odors from the head area, and more interested in odors from the tail as compared to the trunk area. Males displayed different sniffing and self-grooming behaviors when they were exposed to odors from lactating females as compared to non-lactating females. Males also spent more time sniffing and engaged in more sniffing behaviors in response to odors from the lactating females' tail area as compared to the same odors from non-lactating females. Similarly, males spent more time self-grooming and engaged in more self-grooming behaviors in the presence of individual odors from lactating females as compared to individual odors from non-lactating females. Partial correlation analyses revealed that the frequency of self-grooming was significantly correlated with the frequency of tail area sniffs. Results from this experiment suggest that sexual attractiveness of lactating females is stronger than that of non-lactating females. Furthermore, the partial correlation analysis demonstrated that self-grooming in males is induced by odors from the tail area of females. Collectively, these results support the hypothesis that sexual chemical signals from females can induce self-grooming behavior in male root voles. Self-grooming may also reflect the

  11. Is reproduction costly? No increase of oxidative damage in breeding bank voles. (United States)

    Ołdakowski, Łukasz; Piotrowska, Zaneta; Chrzaácik, Katarzyna M; Sadowska, Edyta T; Koteja, Paweł; Taylor, Jan R E


    According to life-history theory, investment in reproduction is associated with costs, which should appear as decreased survival to the next reproduction or lower future reproductive success. It has been suggested that oxidative stress may be the proximate mechanism of these trade-offs. Despite numerous studies of the defense against reactive oxygen species (ROS) during reproduction, very little is known about the damage caused by ROS to the tissues of wild breeding animals. We measured oxidative damage to lipids and proteins in breeding bank vole (Myodes glareolus) females after rearing one and two litters, and in non-breeding females. We used bank voles from lines selected for high maximum aerobic metabolic rates (which also had high resting metabolic rates and food intake) and non-selected control lines. The oxidative damage was determined in heart, kidneys and skeletal muscles by measuring the concentration of thiobarbituric acid-reactive substances, as markers of lipid peroxidation, and carbonyl groups in proteins, as markers of protein oxidation. Surprisingly, we found that the oxidative damage to lipids in kidneys and muscles was actually lower in breeding than in non-breeding voles, and it did not differ between animals from the selected and control lines. Thus, contrary to our predictions, females that bred suffered lower levels of oxidative stress than those that did not reproduce. Elevated production of antioxidant enzymes and the protective role of sex hormones may explain the results. The results of the present study do not support the hypothesis that oxidative damage to tissues is the proximate mechanism of reproduction costs.

  12. Social isolation impairs adult neurogenesis in the limbic system and alters behaviors in female prairie voles. (United States)

    Lieberwirth, Claudia; Liu, Yan; Jia, Xixi; Wang, Zuoxin


    Disruptions in the social environment, such as social isolation, are distressing and can induce various behavioral and neural changes in the distressed animal. We conducted a series of experiments to test the hypothesis that long-term social isolation affects brain plasticity and alters behavior in the highly social prairie vole (Microtus ochrogaster). In Experiment 1, adult female prairie voles were injected with a cell division marker, 5-bromo-2'-deoxyuridine (BrdU), and then same-sex pair-housed (control) or single-housed (isolation) for 6 weeks. Social isolation reduced cell proliferation, survival, and neuronal differentiation and altered cell death in the dentate gyrus of the hippocampus and the amygdala. In addition, social isolation reduced cell proliferation in the medial preoptic area and cell survival in the ventromedial hypothalamus. These data suggest that long-term social isolation affects distinct stages of adult neurogenesis in specific limbic brain regions. In Experiment 2, isolated females displayed higher levels of anxiety-like behaviors in both the open field and elevated plus maze tests and higher levels of depression-like behavior in the forced swim test than controls. Further, isolated females showed a higher level of affiliative behavior than controls, but the two groups did not differ in social recognition memory. Together, our data suggest that social isolation not only impairs cell proliferation, survival, and neuronal differentiation in limbic brain areas, but also alters anxiety-like, depression-like, and affiliative behaviors in adult female prairie voles. These data warrant further investigation of a possible link between altered neurogenesis within the limbic system and behavioral changes.

  13. Autonomic substrates of the response to pups in male prairie voles.

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    William M Kenkel

    Full Text Available Caregiving by nonparents (alloparenting and fathers is a defining aspect of human social behavior, yet this phenomenon is rare among mammals. Male prairie voles (Microtus ochrogaster spontaneously exhibit high levels of alloparental care, even in the absence of reproductive experience. In previous studies, exposure to a pup was selectively associated with increased activity in oxytocin and vasopressin neurons along with decreased plasma corticosterone. In the present study, physiological, pharmacological and neuroanatomical methods were used to explore the autonomic and behavioral consequences of exposing male prairie voles to a pup. Reproductively naïve, adult male prairie voles were implanted with radiotransmitters used for recording ECG, temperature and activity. Males responded with a sustained increase in heart-rate during pup exposure. This prolonged increase in heart rate was not explained by novelty, locomotion or thermoregulation. Although heart rate was elevated during pup exposure, respiratory sinus arrhythmia (RSA did not differ between these males and males exposed to control stimuli indicating that vagal inhibition of the heart was maintained. Blockade of beta-adrenergic receptors with atenolol abolished the pup-induced heart rate increase, implicating sympathetic activity in the pup-induced increase in heart rate. Blockade of vagal input to the heart delayed the males' approach to the pup. Increased activity in brainstem autonomic regulatory nuclei was also observed in males exposed to pups. Together, these findings suggest that exposure to a pup activates both vagal and sympathetic systems. This unique physiological state (i.e. increased sympathetic excitation of the heart, while maintaining some vagal cardiac tone associated with male caregiving behavior may allow males to both nurture and protect infants.

  14. Comparative toxicity of acephate in laboratory mice, white-footed mice, and meadow voles (United States)

    Rattner, B.A.; Hoffman, D.J.


    The LD50 (95% confidence limits) of the organophosphorus insecticide acephate was estimated to be 351, 380, and 321 mg/kg (295?416, 280?516, and 266?388 mg/kg) for CD-1 laboratory mice (Mus musculus), white-footed mice (Peromyscus leucopus noveboracensis), and meadow voles (Microtus pennsylvanicus), respectively. In a second study, these species were provided mash containing 0, 25, 100, and 400 ppm acephate for five days. Brain and plasma cholinesterase activities were reduced in a dose-dependent manner to a similar extent in the three species (inhibition of brain acetyl-cholinesterase averaged for each species ranged from 13 to 22% at 25 ppm, 33 to 42% at 100 ppm, and 56 to 57% at 400 ppm). Mash intake, body or liver weight, plasma enzyme activities (alkaline phosphatase, alanine and aspartate aminotransferase), hepatic enzyme activities (aniline hydroxylase, 7-ethoxycoumarin O-deethylase, and glutathione S-transferase), and cytochrome content (P-450 and b5) were not affected by acephate ingestion, although values differed among species. In a third experiment, mice and voles received 400 ppm acephate for 5 days followed by untreated food for up to 2 weeks. Mean inhibition of brain acetylcholin-esterase for the three species ranged from 47 to 58% on day 5, but by days 12 and 19, activity had recovered to 66 to 76% and 81 to 88% of concurrent control values. These findings indicate that CD-1 laboratory mice, white-footed mice, and meadow voles are equally sensitive to acephate when maintained under uniform laboratory conditions. Several factors (e.g., behavior, food preference, habitat) could affect routes and degree of exposure in the field, thereby rendering some species of wild rodents ecologically more vulnerable to organophosphorus insecticides.

  15. Estimation of thyroid gland state of voles natural populations from increased radioactive background territories

    Energy Technology Data Exchange (ETDEWEB)

    Raskosha, O.; Ermakova, O.; Kaneva, A. [Institute of Biology of Komi Scientific Center, Ural Division of Russian Academy of Science (Russian Federation)


    Investigation of effects caused in biological objects by chronic low-intensity radiation in their natural habitats is one of the most important problems of modern radioecology. The aim of our work - complex estimation of state of thyroid gland of voles inhabiting increased radioactive background territories. We investigated tundra voles (Microtus oeconomus Pall.) that were sampled at different stages of population cycle from the experimental and the control sites in the Uhta region of the Komi Republic, Russia. Experimental site contamination resulted from commercial extraction od radium between the 1930's and 1950's. Irradiation exposure dose at the site was 50-2000 mR/h (at the control site 10-15 mR/h). Complex estimation of thyroid was made by histological, morpho-metrical, radioimmunological and cytogenetic methods. Results showed high sensitivity of thyroid gland of tundra voles from chronically irradiated natural populations. We found reliable changes in morphological features of thyroid, in the level of thyroidal hormones and increased frequency of cells with micro-nucleuses in animals sampled from the experimental site as compared with the control ones. It was also showed, that chronic exposure of ionizing irradiation at the same range of absorbed doses can cause different effects in animals depending on sex, age and the stage of population cycle. This confirms the need of including these biological factors to analysis of low doses effects in the natural populations during radioecological studies. Investigations were supported by RFBR grants No. 13-04-01750? and No. 13-04-90351-RBUa. Document available in abstract form only. (authors)

  16. Early Intranasal Vasopressin Administration Impairs Partner Preference in Adult Male Prairie Voles (Microtus ochrogaster

    Directory of Open Access Journals (Sweden)

    Trenton C. Simmons


    Full Text Available Research supports a modulatory role for arginine vasopressin (AVP in the expression of socially motivated behaviors in mammals. The acute effects of AVP administration are demonstrably pro-social across species, providing the justification for an ever-increasing measure of clinical interest over the last decade. Combining these results with non-invasive intranasal delivery results in an attractive system for offering intranasal AVP (IN-AVP as a therapeutic for the social impairments of children with autism spectrum disorder. But, very little is known about the long-term effects of IN-AVP during early development. In this experiment, we explored whether a single week of early juvenile administration of IN-AVP (low = 0.05 IU/kg, medium = 0.5 IU/kg, high = 5.0 IU/kg could impact behavior across life in prairie voles. We found increases in fecal boli production during open field and novel object recognition testing for the medium dose in both males and females. Medium-dose females also had significantly more play bouts than control when exposed to novel conspecifics during the juvenile period. Following sexual maturity, the medium and high doses of IN-AVP blocked partner preference formation in males, while no such impairment was found for any of the experimental groups in females. Finally, the high-dose selectively increased adult male aggression with novel conspecifics, but only after extended cohabitation with a mate. Our findings confirm that a single week of early IN-AVP treatment can have organizational effects on behavior across life in prairie voles. Specifically, the impairments in pair-bonding behavior experienced by male prairie voles should raise caution when the prosocial effects of acute IN-AVP demonstrated in other studies are extrapolated to long-term treatment.

  17. Evidence that bank vole PrP is a universal acceptor for prions.

    Directory of Open Access Journals (Sweden)

    Joel C Watts


    Full Text Available Bank voles are uniquely susceptible to a wide range of prion strains isolated from many different species. To determine if this enhanced susceptibility to interspecies prion transmission is encoded within the sequence of the bank vole prion protein (BVPrP, we inoculated Tg(M109 and Tg(I109 mice, which express BVPrP containing either methionine or isoleucine at polymorphic codon 109, with 16 prion isolates from 8 different species: humans, cattle, elk, sheep, guinea pigs, hamsters, mice, and meadow voles. Efficient disease transmission was observed in both Tg(M109 and Tg(I109 mice. For instance, inoculation of the most common human prion strain, sporadic Creutzfeldt-Jakob disease (sCJD subtype MM1, into Tg(M109 mice gave incubation periods of ∼200 days that were shortened slightly on second passage. Chronic wasting disease prions exhibited an incubation time of ∼250 days, which shortened to ∼150 days upon second passage in Tg(M109 mice. Unexpectedly, bovine spongiform encephalopathy and variant CJD prions caused rapid neurological dysfunction in Tg(M109 mice upon second passage, with incubation periods of 64 and 40 days, respectively. Despite the rapid incubation periods, other strain-specified properties of many prion isolates--including the size of proteinase K-resistant PrPSc, the pattern of cerebral PrPSc deposition, and the conformational stability--were remarkably conserved upon serial passage in Tg(M109 mice. Our results demonstrate that expression of BVPrP is sufficient to engender enhanced susceptibility to a diverse range of prion isolates, suggesting that BVPrP may be a universal acceptor for prions.

  18. Habitat fragmentation, vole population fluctuations, and the ROMPA hypothesis: An experimental test using model landscapes. (United States)

    Batzli, George O


    Increased habitat fragmentation leads to smaller size of habitat patches and to greater distance between patches. The ROMPA hypothesis (ratio of optimal to marginal patch area) uniquely links vole population fluctuations to the composition of the landscape. It states that as ROMPA decreases (fragmentation increases), vole population fluctuations will increase (including the tendency to display multi-annual cycles in abundance) because decreased proportions of optimal habitat result in greater population declines and longer recovery time after a harsh season. To date, only comparative observations in the field have supported the hypothesis. This paper reports the results of the first experimental test. I used prairie voles, Microtus ochrogaster, and mowed grassland to create model landscapes with 3 levels of ROMPA (high with 25% mowed, medium with 50% mowed and low with 75% mowed). As ROMPA decreased, distances between patches of favorable habitat (high cover) increased owing to a greater proportion of unfavorable (mowed) habitat. Results from the first year with intensive live trapping indicated that the preconditions for operation of the hypothesis existed (inversely density dependent emigration and, as ROMPA decreased, increased per capita mortality and decreased per capita movement between optimal patches). Nevertheless, contrary to the prediction of the hypothesis that populations in landscapes with high ROMPA should have the lowest variability, 5 years of trapping indicated that variability was lowest with medium ROMPA. The design of field experiments may never be perfect, but these results indicate that the ROMPA hypothesis needs further rigorous testing. © 2016 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and John Wiley & Sons Australia, Ltd.

  19. Taphonomic alterations by the rodent species woodland vole (Microtus pinetorum) upon human skeletal remains. (United States)

    Pokines, James T


    This forensic case report describes the taphonomic effects of woodland vole (Microtus pinetorum) upon a set of skeletonized human remains recovered in Massachusetts, USA. Remains of an individual of this rodent species were discovered where it had been nesting inside the human cranium. Fine, parallel grooves indicative of small rodent gnawing were noted on multiple postcranial elements, and all isolated grooves were consistent in size with the incisors of this species. Other taphonomic alterations to these remains include some gnawing damage and dispersal by large carnivores. This case represents the first report of this rodent species affecting human remains. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  20. Beyond the Mediterranean peninsulas: evidence of central European glacial refugia for a temperate forest mammal species, the bank vole (Clethrionomys glareolus). (United States)

    Deffontaine, V; Libois, R; Kotlík, P; Sommer, R; Nieberding, C; Paradis, E; Searle, J B; Michaux, J R


    This study details the phylogeographic pattern of the bank vole, Clethrionomys glareolus, a European rodent species strongly associated with forest habitat. We used sequences of 1011 base pairs of the mitochondrial DNA cytochrome b gene from 207 bank voles collected in 62 localities spread throughout its distribution area. Our results reveal the presence of three Mediterranean (Spanish, Italian and Balkan) and three continental (western, eastern and 'Ural') phylogroups. The endemic Mediterranean phylogroups did not contribute to the post-glacial recolonization of much of the Palaearctic range of species. Instead, the major part of this region was apparently recolonized by bank voles that survived in glacial refugia in central Europe. Moreover, our phylogeographic analyses also reveal differentiated populations of bank voles in the Ural mountains and elsewhere, which carry the mitochondrial DNA of another related vole species, the ruddy vole (Clethrionomys rutilus). In conclusion, this study demonstrates a complex phylogeographic history for a forest species in Europe which is sufficiently adaptable that, facing climate change, survives in relict southern and northern habitats. The high level of genetic diversity characterizing vole populations from parts of central Europe also highlights the importance of such regions as a source of intraspecific genetic biodiversity.

  1. Influence of photoperiod and sex on locomotor behavior of meadow voles (Microtus pennsylvanicus) in an automated light-dark 'anxiety' test. (United States)

    Ossenkopp, Klaus-Peter; van Anders, Sari M; Engeland, Christopher G; Kavaliers, Martin


    This study examined the influence of photoperiod on affective behavior (anxiety) of adult male and female meadow voles (Microtus pennsylvanicus), maintained in either a long or short day photoperiod, when tested in an automated (VersaMax) light-dark test. The light-dark test is based on an innate aversion of rodents to novel, brightly illuminated spaces and has been used with laboratory raised species, such as mice, to assess anxiety and/or fear related behaviors. Male and female meadow voles, housed either in a long day (LD: 16 h light) or short day (SD: 8 h light) photoperiod, were tested in the light-dark apparatus for 30 min on 3 consecutive days. All animals spent significantly (p dark chamber. LD voles, especially females, spent significantly less time in the brightly lit area than did SD voles. Both horizontal and vertical movements occurred less frequently per unit time in the dark area relative to the light, but only in the LD voles. LD female voles were the least active group in the dark area on the first test day but the most active group in the light area, despite spending the least amount of time in this area on the second and third test days. The present results show that LD voles exhibit more anxiety related behaviors in this test situation than do SD voles. LD females avoided the brightly lit area the most, particularly when the apparatus was novel. Thus, both photoperiod and sex influence situation-based anxiety in this species. These findings suggest that meadow voles are an excellent animal model in which to examine the role of gonadal hormones, and their modulation of defence related neural systems, in the induction of anxiety.

  2. Chronic metals ingestion by prairie voles produces sex-specific deficits in social behavior: an animal model of autism. (United States)

    Curtis, J Thomas; Hood, Amber N; Chen, Yue; Cobb, George P; Wallace, David R


    We examined the effects of chronic metals ingestion on social behavior in the normally highly social prairie vole to test the hypothesis that metals may interact with central dopamine systems to produce the social withdrawal characteristic of autism. Relative to water-treated controls, 10 weeks of chronic ingestion of either Hg(++) or Cd(++) via drinking water significantly reduced social contact by male voles when they were given a choice between isolation or contact with an unfamiliar same-sex conspecific. The effects of metals ingestion were specific to males: no effects of metals exposure were seen in females. Metals ingestion did not alter behavior of males allowed to choose between isolation or their familiar cage-mates, rather than strangers. We also examined the possibility that metals ingestion affects central dopamine functioning by testing the voles' locomotor responses to peripheral administration of amphetamine. As with the social behavior, we found a sex-specific effect of metals on amphetamine responses. Males that consumed Hg(++) did not increase their locomotor activity in response to amphetamine, whereas similarly treated females and males that ingested only water significantly increased their locomotor activities. Thus, an ecologically relevant stimulus, metals ingestion, produced two of the hallmark characteristics of autism - social avoidance and a male-oriented bias. These results suggest that metals exposure may contribute to the development of autism, possibly by interacting with central dopamine function, and support the use of prairie voles as a model organism in which to study autism.

  3. Flooding ecology of voles, mice and shrews: the importance of geomorphological and vegetational heterogeneity in river floodplains

    NARCIS (Netherlands)

    Wijnhoven, S.; Velde, G. van der; Leuven, R.S.E.W.; Smits, A.J.M.


    Since voles, mice and shrews are important animals in food chains of river floodplains, there is a need for data on their spatial and temporal distribution in periodically flooded areas. During a live trapping study between two successive floods in an embanked river floodplain, the ’Afferdensche en

  4. Post-Hoc Pattern-Oriented Testing and Tuning of an Existing Large Model: Lessons from the Field Vole

    DEFF Research Database (Denmark)

    Topping, Christopher John; Dalkvist, Trine; Grimm, Volker


    develop an existing agent-based model of the field vole (Microtus agrestis), which was developed and tested within the ALMaSS framework. This framework is complex because it includes a high-resolution representation of the landscape and its dynamics, of the individual’s behavior, and of the interaction...

  5. Novel, species-typical esters from preputial glands of sympatric voles,Microtus montanus andM. pennsylvanicus. (United States)

    Welsh, C J; Moore, R E; Bartelt, R J; Jackson, L L


    Olfactory signals may facilitate species recognition between the sympatric voles,Microtus montanus andM. pennsylvanicus. In an effort to isolate and identify compounds that might contribute to such a chemical communication system, the preputial glands of those voles have been examined. Morphological examinations show both vole species possess preputial glands; however, the glands ofM. montanus are much larger than those ofM. pennsylvanicus. Gas Chromatographie analysis revealed that the preputial glands ofM. montanus contain a series of species-typical lipids that are not found inM. pennsylvanicus. Using gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometry, the species-typical lipids were identified as esters of branched, saturated, and unsaturated C5 and C4 alcohols and straight-chain C16, and "iso" branched C17 fatty acids. This is the first description of such esters from mammalian tissues. The results are discussed relative to the possibility that the species-typical esters act as species recognition cues for the sympatric voles.

  6. Female host sex-biased parasitism with the rodent stomach nematode Mastophorus muris in wild bank voles (Myodes glareolus). (United States)

    Grzybek, Maciej; Bajer, Anna; Behnke-Borowczyk, Jolanta; Al-Sarraf, Mohammed; Behnke, Jerzy M


    Abundance and prevalence of helminth infections often differ between host sexes, and are usually biased in favor of males. Relatively few cases of female-biased parasitism have been reported. We sampled bank voles in three woodland sites in N.E. Poland over 11 years at 3-4-year intervals, and assessed their parasite burdens. Prevalence and abundance of the stomach nematode Mastophorus muris were consistently higher among females. Among adult female bank voles from the two sites that showed the highest prevalence with M. muris, both prevalence and abundance were significantly higher in lactating bank voles, but not pregnant animals, and the effect of lactation was evident in both sites, in all four surveys, and in both age classes. Although the magnitude of the effect of lactation varied between years, it was not confounded by any significant interactions with other factors. We hypothesize that mature and reproductively active female bank voles are subject to higher exposure compared with males of similar age, as a consequence of the increased content of invertebrates in their diet, including the intermediate hosts of M. muris, required to meet the higher increased energy and protein demands of nursing litters throughout the summer months.

  7. Temporal niche switching and reduced nest attendance in response to heat dissipation limits in lactating common voles (Microtus arvalis)

    NARCIS (Netherlands)

    van der Vinne, Vincent; Simons, Mirre J.P.; Reimert, Inonge; Gerkema, Menno P.


    According to the heat dissipation limit theory, maximum metabolic turnover is limited by the capacity of the body to dissipate excess heat. Small mammals, including common voles (Microtus arvalis), face a heat dissipation limitation during lactation. Pup growth and milk production are reduced under

  8. Ongoing ultradian activity rhythms in the common vole, Microtus arvalis, during deprivations of food, water and rest

    NARCIS (Netherlands)

    Gerkema, Menno P.; Leest, Floris van der


    The timing mechanism underlying ultradian (2-3 h) activity patterns in the common vole, Microtus arvalis, was studied using behavioural deprivation experiments. These were aimed at distinguishing between a homeostatic control mechanism, in which the rhythmic behaviour itself is part of the causal lo

  9. Phase Control of Ultradian Feeding Rhythms in the Common Vole (Microtus arvalis) : The Roles of Light and the Circadian System

    NARCIS (Netherlands)

    Gerkema, Menno P.; Daan, Serge; Wilbrink, Marieke; Hop, Martina W.; Leest, Floris van der


    In their ultradian (2- to 3-hr) feeding rhythm, common voles show intraindividual synchrony from day to day, as well as interindividual synchrony between members of the population, even at remote distances. This study addresses the question of how resetting of the ultradian rhythm, a prerequisite fo

  10. Chronic social isolation enhances reproduction in the monogamous prairie vole (Microtus ochrogaster). (United States)

    Perry, Adam N; Carter, C Sue; Cushing, Bruce S


    Chronic stressors are generally considered to disrupt reproduction and inhibit mating. Here we test the hypothesis that a chronic stressor, specifically social isolation, can facilitate adaptive changes that enhance/accelerate reproductive effort. In general, monogamous species display high levels of prosociality, delayed sexual maturation, and greater parental investment in fewer, higher quality offspring compared with closely related polygynous species. We predicted that chronic social isolation would promote behavioral and neurochemical patterns in prairie voles associated with polygyny. Male and female prairie voles were isolated for four weeks and changes in mating behavior, alloparental care, estrogen receptor (ER) α expression and tyrosine hydroxylase (TH) expression in brain regions regulating sociosexual behavior were examined. In males, isolation accelerated copulation, increased ERα in the medial amygdala (MEApd) and bed nucleus of the stria terminalis (BSTpm), and reduced TH expression in the MEApd and BSTpm, but had no effect on alloparental behavior. In females, isolation resulted in more rapid estrus induction and reduced TH expression in the MEApd and BSTpm, but had no effect on estradiol sensitivity or ERα expression. The results support the hypothesis that ERα expression in the MEApd and BSTpm is a critical determinant of male copulatory behavior and/or mating system. The lack of change in alloparental behavior suggests that changes in prosocial behavior are selective and regulated by different mechanisms. The results also suggest that TH in the MEApd and BSTpm may play a critical role in determining mating behavior in both sexes.

  11. Male prairie voles with different avpr1a microsatellite lengths do not differ in courtship behaviour. (United States)

    Graham, Brittney M; Solomon, Nancy G; Noe, Douglas A; Keane, Brian


    Females are generally expected to be selective when choosing their social and sexual partners. In a previous laboratory study, female prairie voles (Microtus ochrogaster) showed significant social and sexual preferences for males with longer microsatellite DNA within the avpr1a gene encoding the vasopressin 1a receptor, as predicted if females select mates whose parental behaviour should increase female reproductive success. We tested the hypothesis that males with short versus long avpr1a microsatellite alleles exhibit differences in courtship behaviour, which could act as cues for female mate preference. The only behavioural difference we detected between males with short versus long avpr1a microsatellite alleles in mate preference trials was that males with short avpr1a microsatellite alleles sniffed the anogenital region of females more frequently during the first two days of the trials. Our results did not strongly support the hypothesis that a male's avpr1a genotype predicts the courtship behaviours we measured and suggests that other courtship behaviours or traits, such as odour and vocalizations, may be more important to female prairie voles when choosing mates. Additional studies using a wider array of species are needed to assess the degree to which male mammal courtship behaviour provides information on mate quality to females.

  12. Accumulation of lead and organochlorine residues in captive American kestrels fed pine voles from apple orchards (United States)

    Stendell, R.C.; Beyer, W.N.; Stehn, R.A.


    Pine voles (Microtus pinetorum) were collected from pesticide-treated orchards in New York and fed to 3 captive American kestrels (Falco sparverius) for 60 days to evaluate potential hazards from soil-borne persistent insecticides. Three control kestrels were fed uncontaminated laboratory mice (Mus musculus). The pine voles contained an average of 38 ppm lead, 48 ppm DDE and 1.2 ppm dieldrin (dry weight). The kestrels accumulated sublethal amounts of lead (1 ppm lead wet weight) in their livers. In contrast, DDE and dieldrin accumulated in the tissues and brains of kestrels to toxicologically significant concentrations. Control kestrels remained healthy and accumulated insignificant concentrations of the contaminants. The results indicated raptors may not be significantly at risk from lead residues in soil and biota following field applications of lead arsenate. However, sublethal effects may be expected from the level of contamination by organochlorine pesticides. raptors may not be significantly at risk from lead residues in soil and biota following field applications of lead arsenate. However, sublethal effects may be expected from the level of contamination byorganochlorine pesticides. lead wet weight) in their livers.

  13. Alloparenting experience affects future parental behavior and reproductive success in prairie voles (Microtus ochrogaster). (United States)

    Stone, Anita Iyengar; Mathieu, Denise; Griffin, Luana; Bales, Karen Lisa


    Various hypotheses have been proposed to explain the function of alloparental behavior in cooperatively breeding species. We examined whether alloparental experience as juveniles enhanced later parental care and reproductive success in the prairie vole (Microtus ochrogaster), a cooperatively breeding rodent. Juveniles cared for one litter of siblings (1EX), two litters of siblings (2EX) or no siblings (0EX). As adults, these individuals were mated to other 0EX, 1EX or 2EX voles, yielding seven different pair combinations, and we recorded measures of parental behaviors, reproductive success, and pup development. As juveniles, individuals caring for siblings for the first time were more alloparental; and as adults, 0EX females paired with 0EX males spent more time in the nest with their pups. Taken together, these results suggest that inexperienced animals spend more time in infant care. As parents, 1EX males spent more time licking their pups than 2EX and 0EX males. Pups with either a 1EX or 2EX parent gained weight faster than pups with 0EX parents during certain developmental periods. While inexperienced animals may spend more time in pup care, long-term benefits of alloparenting may become apparent in the display of certain, particularly important parental behaviors such as licking pups, and in faster weight gain of offspring.

  14. Genetic variation and population dispersal of Yangtze voles Microtus fortis calamorum in the Dongting Lake region

    Institute of Scientific and Technical Information of China (English)

    Zongming GUO; Pengfei SONG; Cong GUO; Zhaobin SONG; Yong WANG; Bo LI; Meiwen ZHANG; Jianghong RAN


    To understand genetic variation and population dispersal in the Yangtze vole Microtusfortis calamorum distributed in the Dongting Lake region,144 individuals were collected from six habitat patches.The mitochondrial DNA control region was sequenced and 17 haplotypes were observed.Of the six investigated populations,haplotype and nucleotide diversities of those from larger patches were higher than those from smaller patches.Nonparametric correlation analysis showed that patch size had a positive correlation with haplotype diversity (r =0.943,P < 0.01).A neighbour-joining tree of the 17 hapiotypes showed no geographic genetic structure among the six populations.Analysis of isolation by distance showed that genetic differentiation among the six populations was not positively related to geographic distance.Analysis of mismatch distribution indicated that the voles had passed through a population expansion.The pattern of haplotype distribution in the Changsha population suggests that the population was established by a founder effect [Current Zoology 58 (2):211-220,2012].

  15. Interspecific relations of parasites of bank vole Myodes glareolus (Schreber, 1780

    Directory of Open Access Journals (Sweden)

    Bugmyrin Sergey


    Adaptation to coexistence had a tendency to the balancing of a pathogenic action of a parasite complex with an immunophysiological status of the host. The observed frequency distribution of the number of parasites in the bank vole complies with a lognormal distribution (Fig. 1. The analysis of co-occurrence of bank vole parasites showed that the presence or absence of one parasite in the host does not affect the presence of another. The results on the co-occurrence of parasites indicate that they don’t influence each other negatively (Table 1. Correlation of abundance in the concurrent infections were statistically reliable (p<0.05 for 6 of 55 examined parasite pairs. There were H. glareoly – I. trianguliceps (Pearson's correlation coefficient: 0.21, I. persulcatus - Hi. isabellinus (0.12, I. persulcatus – Ct. uncinatus (0.35, Hg. nidi - E. stabularis (0.13, E. stabularis - M. rectangulatus (0.25, M. rectangulatus - P. silvatici (0.52. All significant associations were positive (Table 2–4. It might be explained by the similar requirements of the parasites to the conditions of their habitat.

  16. Application of grain baits to control common vole Microtus arvalis (Pallas, 1778 in alfalfa crops, Serbia

    Directory of Open Access Journals (Sweden)

    Jokić G.


    Full Text Available In order to compare the efficacies of conventional (cholecalciferol and bromadiolone and new (sodium selenite rodenticides, applied in the grain bait formulation on the whole-grain of wheat (Triticum aestivum and triticale (Triticasecale in alfalfa crops, experiments were conducted at two sites near Belgrade, Serbia, in the spring of 2009, using a standard EPPO method. The presence of rodent populations, their spatial distribution and density indices were evaluated by pretreatment census and rodenticide efficacy by counting active holes, 14 and 28 days after treatment. The average Microtus arvalis numbers of 158/ha and 184/ha were found to cause 7.4% and 9.6% alfalfa green biomass yield decreases, respectively. Twenty-eight days after treatment, the average efficacy of grain bait formulation (on wheat and triticale grains of sodium selenite and cholecalciferol was 81%, while bromadiolone which had a higher efficiency, 85%, in the control of the common vole in alfalfa crops. The analysis of variance (ANOVA showed that the origin of active substances, bases and associated interactions a.s x based on the efficacy-investigated grain baits did not have a statistically significant impact on the expression efficiency of the tested baits. Triticale grains can be used as carriers of active substances, sodium selenite, cholecalciferol or bromadiolone in preparation baits. Control of M. arvalis with the new rodenticide, sodium selenite, gave efficacy results about equal to that of cholecalciferol and bromadiolone and, therefore, provided a possible alternative rodenticide for vole control in alfalfa.

  17. Emotional attachment of pre-weaning pups to mothers and fathers in mandarin voles. (United States)

    He, Zhixiong; Zhang, Shuwei; Yu, Chengjun; Li, Yani; Jia, Rui; Tai, Fadao


    Studies into the effects of maternal and paternal deprivation on the brain and behavior are traditionally done on animals from postnatal day 0 to 14 when parents display high levels of licking and grooming. Deprivation experiments that reveal attachment conducted during this period are confounded because physiological and emotional deprivation occur simultaneously. Whether rodent pups of greater physiological independence from postnatal 14 to 21days show emotional attachment towards mothers and fathers remains unclear. Here we establish a new animal model for attachment experiments in animals 14-21days old using monogamous mandarin voles (Microtus mandarinus). Levels of emotional attachment of pups from postnatal 14 to 21days were measured using preference tests. Pups spent more time in contact with their mothers, more time approaching, sniffing, climbing and walking near their mothers, and emitted more calls on their mother's side compared to an unknown female. They also showed a preference for their fathers over an unknown male. While pups displayed attachment to both their mothers and fathers, levels directed towards mothers were higher in tests when mothers and fathers were presented simultaneously. These results indicate that mandarin voles can be used as an animal model to investigate the effects of early emotional attachment disruption on the adult brain and behavior.

  18. Effect of copper exposure on reproductive ability in the bank vole (Myodes glareolus). (United States)

    Miska-Schramm, Agata; Kruczek, Małgorzata; Kapusta, Joanna


    The amount of copper in natural ecosystems is steadily increasing, due to human activities. It accumulates in plants, posing a threat to herbivores. In polluted areas the population density of small rodents is observed to be lower. The decline in rodent numbers may be caused by increased mortality or diminished fertility. This study examined the effect of copper on the reproductive activity of the bank vole (Myodes glareolus), a small rodent which during foraging often wanders into fields where it might be exposed to pollution. The animals were treated with solutions of 0, 150 or 600 ppm Cu. After 12 weeks of exposure the quality and quantity of the male's sperm was tested. To assess morphological development we compared the experimental groups for body weight, the weight of the male's testes and accessory sex glands, the female's uterus, and the number of matured ovary follicles in tested females. At both doses, copper administration led to lower sperm count and caused sperm head anomalies. The higher dose compromised sperm tail membrane integrity, viability and motility. No effect of copper on morphological development was observed in males, and only the lower dose increased testes weight. In females the higher dose had a negative effect on morphological development, and the lower dose increased uterus weight. No effect of copper on ovarian follicle number was found. For the first time, the morphology of the most typical ovarian follicles of the bank vole is presented.

  19. Proliferation and apoptosis in early molar morphogenesis-- voles as models in odontogenesis. (United States)

    Setkova, Jana; Lesot, Herve; Matalova, Eva; Witter, Kirsti; Matulova, Petra; Misek, Ivan


    Proliferation and apoptosis play crucial roles in the development of multicellular organisms. Their precise balance is necessary for tissue homeostasis throughout life. The developing dentition is a suitable model to study proliferation and apoptosis during embryogenesis, but the corresponding studies have been carried out principally in the mouse. The present study aimed to examine proliferation and apoptosis in the vole (Microtus sp., Rodentia) during the early morphogenesis of the first upper molar and compare it to what is known from the mouse. To this end, apoptosis and proliferation were investigated using histology and computer-aided 3D reconstruction. Mitoses accumulated predominantly in the developing cervical loop. Apoptosis during early odontogenesis showed highly specific spatio-temporal patterns in the dental epithelium. Apoptotic bodies were localised in non-dividing cell populations. They accumulated in the same places as described in the mouse: antemolar vestiges (ED 12.5 15.5), enamel knot (ED 14.5 15.5), stalk and palatally along the whole first molar tooth germ longitudinal axis (ED 15 - 15.5). Early tooth development in the field vole, including the distribution of apoptosis and mitosis, is very similar to that reported in the mouse, with the exception of the antemolar region. The microtine antemolar vestige is preserved longer than the murine one. It is conceivable that additional distinct differences in morphogenetic processes appear later in tooth development.

  20. Regulation of body mass and adiposity in the field vole, Microtus agrestis: a model of leptin resistance. (United States)

    Król, Elzbieta; Speakman, John R


    Adult mammals are typically highly resistant to perturbations in their energy balance. In obese humans, however, this control appears to be lost. Apart from a few exceptional cases, this loss of control occurs despite appropriate levels of circulating leptin -- suggesting that elevated adiposity may be a consequence of failure to respond to the leptin signal: leptin resistance. When cold-acclimated male field voles (Microtus agrestis) are transferred from short (SD, 8 h light) to long (LD, 16 h light) photoperiods, they increase dramatically in body mass and fatness for about 4 weeks. After this period, their mass stabilizes at a new plateau about 25% higher than animals maintained in SD. The increase in adiposity is not caused by significant increases in food intake, but reflects an increase in digestive efficiency. Measures of circulating leptin reveal that the increased adiposity is matched by increased circulating leptin. By infusing voles with exogenous leptin, we have demonstrated that SD voles are leptin sensitive (reducing both body mass and food intake), whereas LD animals are leptin resistant. Voles may therefore be a useful model for understanding the process of leptin resistance. The change in leptin sensitivity in voles was not associated with changes in the levels of gene expression of the orexogenic or anorexogenic neuropeptides, such as neuropeptide Y, agouti-related peptide, POMC and cocaine- and amphetamine-regulated transcript, measured in the hypothalamic arcuate nucleus (ARC). During the phase that body mass was increasing, however, there was a transient increase in the ARC expression of suppressor of cytokine signalling-3 (SOCS3). These data suggest that the changes in the expression of SOCS3 in the ARC may be involved in leptin resistance. However, the mechanism by which these changes may be linked to alterations in digestive efficiency that underpin the changes in adiposity, or how the differences are signalled by changes in photoperiod

  1. Measuring animal welfare within a reintroduction: an assessment of different indices of stress in water voles Arvicola amphibius.

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    Merryl Gelling

    Full Text Available Reintroductions are an increasingly common conservation restoration tool; however, little attention has hitherto been given to different methods for monitoring the stress encountered by reintroduced individuals. We compared ten potential measures of stress within four different categories (neuroendocrine, cell function, body condition and immune system function as proxies for animal welfare in water voles being reintroduced to the Upper Thames region, Oxfordshire, UK. Captive-bred voles were assessed pre-release, and each month post-release for up to five months. Wild-born voles were captured in the field and assessed from two months post-release. Plasma corticosteroid, hydration and body condition of captive-bred voles differed between their pre-release measures and both their first ("short-term" recapture, and their final recapture ("long-term" release, however only body condition and immunocompetence measured using the Nitroblue Tetrazolium (NBT test were significantly different post-release between the first and last recaptures. Captive-bred animals had lower fat reserves, higher weight/length ratios and better immunocompetence (NBT than did wild-born voles. Captive-bred males had higher ectoparasite burdens compared to wild-born males and, as reintroduction site quality decreased, became less hydrated. These observations indicate that some methods can identify changes in the stress response in individuals, highlighting areas of risk in a reintroduction programme. In addition, a single measure may not provide a full picture of the stress experienced; instead, a combination of measures of different physiological systems may give a more complete indication of stress during the reintroduction process. We highlight the need to monitor stress in reintroductions using measures from different physiological systems to inform on possible animal welfare improvements and thus the overall success rate of reintroductions.

  2. Metal exposure and effects in voles and small birds near a mining haul road in Cape Krusenstern National Monument, Alaska (United States)

    Brumbaugh, William G.; Mora, Miguel A.; May, Thomas W.; Phalen, David N.


    Voles and small passerine birds were live-captured near the Delong Mountain Regional Transportation System (DMTS) haul road in Cape Krusenstern National Monument in northwest Alaska to assess metals exposure and sub-lethal biological effects. Similar numbers of animals were captured from a reference site in southern Cape Krusenstern National Monument for comparison. Histopathological examination of selected organs, and analysis of cadmium, lead, and zinc concentrations in liver and blood samples were performed. Voles and small birds captured from near the haul road had about 20 times greater blood and liver lead concentrations and about three times greater cadmium concentrations when compared to those from the reference site, but there were no differences in zinc tissue concentrations. One vole had moderate metastatic mineralization of kidney tissue, otherwise we observed no abnormalities in internal organs or DNA damage in the blood of any of the animals. The affected vole also had the greatest liver and blood Cd concentration, indicating that the lesion might have been caused by Cd exposure. Blood and liver lead concentrations in animals captured near the haul road were below concentrations that have been associated with adverse biological effects in other studies; however, subtle effects resulting from lead exposure, such as the suppression of the activity of certain enzymes, cannot be ruled out for some individual animals. Results from our 2006 reconnaissance-level study indicate that overall, voles and small birds obtained from near the DMTS road in Cape Krusenstern National Monument were not adversely affected by metals exposure; however, because of the small sample size and other uncertainties, continued monitoring of lead and cadmium in terrestrial habitats near the DMTS road is advised.

  3. Hierarchical spatial segregation of two Mediterranean vole species: the role of patch-network structure and matrix composition. (United States)

    Pita, Ricardo; Lambin, Xavier; Mira, António; Beja, Pedro


    According to ecological theory, the coexistence of competitors in patchy environments may be facilitated by hierarchical spatial segregation along axes of environmental variation, but empirical evidence is limited. Cabrera and water voles show a metapopulation-like structure in Mediterranean farmland, where they are known to segregate along space, habitat, and time axes within habitat patches. Here, we assess whether segregation also occurs among and within landscapes, and how this is influenced by patch-network and matrix composition. We surveyed 75 landscapes, each covering 78 ha, where we mapped all habitat patches potentially suitable for Cabrera and water voles, and the area effectively occupied by each species (extent of occupancy). The relatively large water vole tended to be the sole occupant of landscapes with high habitat amount but relatively low patch density (i.e., with a few large patches), and with a predominantly agricultural matrix, whereas landscapes with high patch density (i.e., many small patches) and low agricultural cover, tended to be occupied exclusively by the small Cabrera vole. The two species tended to co-occur in landscapes with intermediate patch-network and matrix characteristics, though their extents of occurrence were negatively correlated after controlling for environmental effects. In combination with our previous studies on the Cabrera-water vole system, these findings illustrated empirically the occurrence of hierarchical spatial segregation, ranging from within-patches to among-landscapes. Overall, our study suggests that recognizing the hierarchical nature of spatial segregation patterns and their major environmental drivers should enhance our understanding of species coexistence in patchy environments.

  4. Increasing oxytocin receptor expression in the nucleus accumbens of pre-pubertal female prairie voles enhances alloparental responsiveness and partner preference formation as adults


    Keebaugh, Alaine C.; Young, Larry J.


    Oxytocin receptors (OXTR) in the nucleus accumbens (NAcc) promote alloparental behavior and partner preference formation in female prairie voles. Within the NAcc there is significant individual variation in OXTR binding and virgin juvenile and adult females with a high density of OXTR in the NAcc display an elevated propensity to engage in alloparental behavior toward novel pups. Over-expression of OXTR in the NAcc of adult female prairie voles using viral vector gene transfer facilitates par...

  5. Yellow-necked mice (Apodemus flavicollis and bank voles (Myodes glareolus as zoomonitors of environmental contamination at a polluted area in Slovakia

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    Jančová Alena


    Full Text Available Abstract Background Free-living wild rodents are often used as zoomonitors of environmental contamination. In the present study, accumulation of cadmium (Cd, copper (Cu, iron (Fe, and zinc (Zn in critical organs of yellow-necked mice (Apodemus flavicollis and bank voles (Myodes glareolus trapped in a polluted area in Nováky, Slovakia was investigated. Methods Yellow-necked mice (n = 8 and bank voles (n = 10 were collected using standard theriological methods for wood ecosystems. All animals were adult males in good physical condition. The concentrations of Cd, Cu, Fe, and Zn in the liver, kidney, and bone were determined by atomic absorption spectrophotometry. Results The highest concentrations of Cd and Zn were found in the bone of both species while Cu and Fe accumulated mainly in kidney or liver. Significant higher concentrations of Cd and Cu were detected in the liver of bank voles than in yellow-necked mice. Similar significant higher levels of Cd and Zn were found in the bone of bank voles. In contrast, significant higher concentrations of Cu and Fe were present in the kidney of yellow-necked mice. Conclusions In the yellow-necked mouse and bank vole, bone seems to accumulate Cd and Zn following prolonged exposure. On the contrary, kidney and liver store Cu and Fe after a long-term environmental exposure. In the present study, bank voles seemed to be more heavy metal loaded zoomonitors than yellow-necked mice.

  6. The evolutionary radiation of Arvicolinae rodents (voles and lemmings: relative contribution of nuclear and mitochondrial DNA phylogenies

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    Paradis Emmanuel


    Full Text Available Abstract Background Mitochondrial and nuclear genes have generally been employed for different purposes in molecular systematics, the former to resolve relationships within recently evolved groups and the latter to investigate phylogenies at a deeper level. In the case of rapid and recent evolutionary radiations, mitochondrial genes like cytochrome b (CYB are often inefficient for resolving phylogenetic relationships. One of the best examples is illustrated by Arvicolinae rodents (Rodentia; Muridae, the most impressive mammalian radiation of the Northern Hemisphere which produced voles, lemmings and muskrats. Here, we compare the relative contribution of a nuclear marker – the exon 10 of the growth hormone receptor (GHR gene – to the one of the mitochondrial CYB for inferring phylogenetic relationships among the major lineages of arvicoline rodents. Results The analysis of GHR sequences improves the overall resolution of the Arvicolinae phylogeny. Our results show that the Caucasian long-clawed vole (Prometheomys schaposnikowi is one of the basalmost arvicolines, and confirm that true lemmings (Lemmus and collared lemmings (Dicrostonyx are not closely related as suggested by morphology. Red-backed voles (Myodini are found as the sister-group of a clade encompassing water vole (Arvicola, snow vole (Chionomys, and meadow voles (Microtus and allies. Within the latter, no support is recovered for the generic recognition of Blanfordimys, Lasiopodomys, Neodon, and Phaiomys as suggested by morphology. Comparisons of parameter estimates for branch lengths, base composition, among sites rate heterogeneity, and GTR relative substitution rates indicate that CYB sequences consistently exhibit more heterogeneity among codon positions than GHR. By analyzing the contribution of each codon position to node resolution, we show that the apparent higher efficiency of GHR is due to their third positions. Although we focus on speciation events spanning the last

  7. Mitogenomic phylogenetics of the bank vole Clethrionomys glareolus, a model system for studying end-glacial colonization of Europe. (United States)

    Filipi, Karolína; Marková, Silvia; Searle, Jeremy B; Kotlík, Petr


    We have revisited the mtDNA phylogeny of the bank vole Clethrionomys glareolus based on Sanger and next-generation Illumina sequencing of 32 complete mitochondrial genomes. The bank vole is a key study species for understanding the response of European fauna to the climate change following the Last Glacial Maximum (LGM) and one of the most convincing examples of a woodland mammal surviving in cryptic northern glacial refugia in Europe. The genomes sequenced included multiple representatives of each of the eight bank vole clades previously described based on cytochrome b (cob) sequences. All clades with the exception of the Basque - likely a misidentified pseudogene clade - were highly supported in all phylogenetic analyses and the relationships between the clades were resolved with high confidence. Our data extend the distribution of the Carpathian clade, the marker of a northern glacial refugium in the Carpathian Mountains, to include Britain and Fennoscandia (but not adjacent areas of continental Europe). The Carpathian sub-clade that colonized Britain and Fennoscandia had a somewhat different history from the sub-clade currently found in or close to the Carpathians and may have derived from a more north-westerly refugial area. The two bank vole populations that colonized Britain at the end of the last glaciation are for the first time linked with particular continental clades, the first colonists with the Carpathian clade and the second colonists with the western clade originating in a more southerly refugium in the vicinity of the Alps. We however found no evidence that a functional divergence of proteins encoded in the mitochondrial genome promoted the partial genetic replacement of the first colonists by the second colonists detected previously in southern Britain. We did identify one codon site that changed more often and more radically in the tree than expected and where the observed amino acid change may affect the reductase activity of the cytochrome bc1

  8. Long-term spatiotemporal stability and dynamic changes in the haemoparasite community of bank voles (Myodes glareolus) in NE Poland. (United States)

    Bajer, Anna; Welc-Falęciak, Renata; Bednarska, Małgorzata; Alsarraf, Mohammed; Behnke-Borowczyk, Jolanta; Siński, Edward; Behnke, Jerzy M


    Long-term field studies on parasite communities are rare but provide a powerful insight into the ecological and evolutionary processes shaping host-parasite interactions. The aim of our study was to identify the principal factors regulating long-term trends in the haemoparasite communities of bank voles, and to this end, we sampled three semi-isolated populations of bank voles (n = 880) in 1999, 2002, 2006 and 2010 in the Mazury lake district region of NE Poland. Overall, 90.8 % of the bank voles harboured at least one of the species of haemoparasites studied. Whilst overall prevalence (all species combined) did not vary significantly between the surveys, different temporal changes were detected among voles in each of the three sites. In voles from Urwitałt, prevalence increased consistently with successive surveys, whereas in Tałty, the peak years were 2002 and 2006, and in Pilchy, prevalence oscillated without a clear pattern. Across the study, bank voles harboured a mean of 1.75 ± 0.034 haemoparasite species, and species richness remained stable with no significant between-year fluctuations or trends. However, each of the five constituent species/genera showed a different pattern of spatio-temporal changes. The overall prevalence of Babesia microti was 4.9 %, but this varied significantly between years peaking in 2006 and declining again by 2010. For Bartonella spp., overall prevalence was 38.7 %, and this varied with year of study, but the temporal pattern of changes differed among the three sites. The overall prevalence of Haemobartonella (Mycoplasma) was 68.3 % with an increase in prevalence with year of study in all three sites. Hepatozoon erhardovae had an overall prevalence of 46.8 % but showed a marked reduction with each successive year of the study, and this was consistent in all three sites. The overall prevalence of Trypanosoma evotomys was 15.4 % varying significantly between sites, but showing temporal stability. While overall prevalence

  9. Modelling the loss of genetic diversity in vole populations in a spatially and temporally varying environment

    DEFF Research Database (Denmark)

    Topping, Christopher John; Østergaard, Siri; Pertoldi, Cino


    a genetically explicit individual-based model (IBM) coupled to a dynamic landscape model was used to obtain measures for the genetic status of simulated vole populations. The rate of loss of expected heterozygosity (He) was calculated for simulated populations using two levels of spatial and temporal...... heterogeneity. Results showed that both spatial and temporal heterogeneity exerted an influence on the rate of loss of genetic diversity, but the precise effect was a balance between the effects of population sub-structuring, the frequency of founder effects and population size. These were in turn related...... of heterozygosity was corrected for the harmonic mean of the population size, the rate of loss was almost identical in the four scenarios. Unlike classical genetic models, IBMs are flexible enough to mimic real population processes under a range of environmental and behavioural conditions. We conclude that IBMs...

  10. Drinking alcohol has sex-dependent effects on pair bond formation in prairie voles. (United States)

    Anacker, Allison M J; Ahern, Todd H; Hostetler, Caroline M; Dufour, Brett D; Smith, Monique L; Cocking, Davelle L; Li, Ju; Young, Larry J; Loftis, Jennifer M; Ryabinin, Andrey E


    Alcohol use and abuse profoundly influences a variety of behaviors, including social interactions. In some cases, it erodes social relationships; in others, it facilitates sociality. Here, we show that voluntary alcohol consumption can inhibit male partner preference (PP) formation (a laboratory proxy for pair bonding) in socially monogamous prairie voles (Microtus ochrogaster). Conversely, female PP is not inhibited, and may be facilitated by alcohol. Behavior and neurochemical analysis suggests that the effects of alcohol on social bonding are mediated by neural mechanisms regulating pair bond formation and not alcohol's effects on mating, locomotor, or aggressive behaviors. Several neuropeptide systems involved in the regulation of social behavior (especially neuropeptide Y and corticotropin-releasing factor) are modulated by alcohol drinking during cohabitation. These findings provide the first evidence to our knowledge that alcohol has a direct impact on the neural systems involved in social bonding in a sex-specific manner, providing an opportunity to explore the mechanisms by which alcohol affects social relationships.

  11. Complete mitochondrial genome sequence of the Chinese scrub vole (Neodon irene). (United States)

    Fan, Longqing; Fan, Zhenxin; Yue, Hao; Zhang, Xiuyue; Liu, Yang; Sun, Zhiyu; Liu, Shaoying; Yue, Bisong


    The Chinese scrub vole (Neodon irene) belongs to the subfamily Arvicolinae, which is restricted to mountain areas at high altitudes (2800-4000). In this study, we sequenced the complete mitochondrial genome of N. irene. It was determined to be 16,367 bases. The nucleotide sequence data of 12 heavy-strand protein-coding genes of N. irene and other 22 rodents were used for phylogenetic analysis. Bayesian inference (BI) and maximum likelihood (ML) were used. Both the BI and ML trees demonstrated that Microtus rossiaemeridionalis and Microtus kikuchii did not cluster together with each other. On the contrary, M. rossiaemeridionalis showed close relationship with N. irene. In the present study, only one sequence from Neodon and two sequences from Microtus were included in the phylogenetic analysis which should contribute to the unusual relationship. Therefore, in order to better understand the phylogenetic relationship within Rodentia, more rodents' complete mitochondrial genomes are required.

  12. Prey selection of Tawny owls (Strix aluco) on Yellow necked mouse and Bank Vole

    DEFF Research Database (Denmark)

    Forsom, H. M.; Sunde, P.; Overskaug, K.

    As predators owls may have a strong impact on mortality of their favourite prey, and may therefore act as important selective agents on their prey species. Little is known, however, about whether owls choose prey randomly or if some prey items suffer a higher risk of predation due to certain life...... history traits. The aim of this master thesis study was to investigate any prey selection of tawny owls on two prey species, yellow-necked mouse (Apodemus flavicollis) and bank voles (Clethrionomys glareolus). Our hypotheses were that the level of exposure might differ between prey items of different sex......, age, and size, causing some individuals to suffer a higher risk of predation from tawny owls than others.The results suggest that males suffer a higher risk of predation from tawny owls than females, and that the different age groups may also experience different risk of predation. It also suggests...

  13. Nematofauna of bank vole: Clethrionomys glareolus (Schreber, 1780 from Mt. Fruška gora (Serbia

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    Bjelić-Čabrilo Olivera N.


    Full Text Available The nematofauna of bank vole (Clethrionomys glareolus was analyzed for the first time from samples collected in our country. The specimens were collected in Fruška Gora National Park (locality of Brankovac. The number of collected specimens was 138, and infestation with seven nematode species was determined: Heligmosomum mixtum (Schulz, 1954, Heligmosomoides glareoli (Baylis, 1928, Syphacia petrusewiczi (Bernard, 1966, S. stroma (Linstow, 1884, Capillaria murissylvatici (Dieseng, 1851, Trichocephalus muris Schrank, 1788, and Aspiculuris tetraptera (Nitzsch, 1821. The species Heligmosomum mixtum, Heligmosomoides glareoli, and Syphacia petrusewiczi represent the first records for the territory of our country. The species best represented in the sample were H. glareoli and S. petrusewiczi. There were no statistically significant differences between the sexes of host species regarding the prevalence, mean intensity, or mean abundance of parasite invasion.

  14. Entraide bénévole Suisse - Thaïlande

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    Qui sommes-nous ? Une équipe de bénévoles désireux d’améliorer le quotidien de familles productrices, au sud-est de la Thaïlande, en vous offrant une production artisanale d’excellentes épices et tisanes de première qualité. CULTIVÉES SANS PESTICIDES NI ENGRAIS. Nous vous offrons plus de 30 moyens de prendre soin de vous et de ceux que vous aimez! Rejoignez-nous sur :  Nous serons le jeudi 1er décembre dans le Bâtiment principal de 10 h 00 à 16 h 00. Les Saveurs du Siam sont parties intégrantes de la FONDATION HOPE-HOUSE «SAWATDI»

  15. Early experiences can alter the size of cortical fields in prairie voles (Microtus ochrogaster) (United States)

    Seelke, A.M.H.; Yuan, S.-M.; Perkeybile, A.M.; Krubitzer, L.A.; Bales, K.L.


    The neocortex of the prairie vole is composed of three well-defined sensory areas and one motor area: primary somatosensory, visual, auditory areas and the primary motor area respectively. The boundaries of these cortical areas are identifiable very early in development, and have been thought to resist alteration by all but the most extreme physical or genetic manipulations. Here we assessed the extent to which the boundaries of sensory/motor cortical areas can be altered by exposing young prairie voles (Microtus ochrogaster) to a chronic stimulus, high or low levels of parental contact, or an acute stimulus, a single dose of saline, oxytocin (OT), or oxytocin antagonist on the day of birth. When animals reached adulthood, their brains were removed, the cortex was flattened, cut parallel to the pial surface, and stained for myelin to identify the architectonic boundaries of sensory and motor areas. We measured the overall proportion of cortex that was myelinated, as well as the proportion of cortex devoted to the sensory and motor areas. Both the chronic and acute manipulations were linked to significant alterations in areal boundaries of cortical fields, but the areas affected differed with different conditions. Thus, differences in parental care and early exposure to OT can both change cortical organization, but their effects are not identical. Furthermore, the effects of both manipulations were sexually dimorphic, with a greater number of statistically significant differences in females than in males. These results indicate that early environmental experience, both through exposure to exogenous neuropeptides and parental contact, can alter the size of cortical fields.

  16. Pika and vole mitochondrial genomes increase support for both rodent monophyly and glires. (United States)

    Lin, Yu-Hsin; Waddell, Peter J; Penny, David


    Complete mitochondrial genomes are reported for a pika (Ochotona collaris) and a vole (Volemys kikuchii) then analysed together with 35 other mitochondrial genomes from mammals. With standard phylogenetic methods the pika joins with the other lagomorph (rabbit) and the vole with the other murid rodents (rat and mouse). In addition, with hedgehog excluded, the seven rodent genomes consistently form a homogeneous group in the unrooted placental tree. Except for uncertainty of the position of tree shrew, the clade Glires (monophyletic rodents plus lagomorphs) is consistently found. The unrooted tree obtained by ProtML (Protein Maximum Likelihood, a program in MOLPHY) is compatible with a reclassification of mammals [Syst. Biol. 48, 1-5 (1999)] which is also supported by other recent studies. However, when this tree is rooted with marsupials plus platypus, the outgroup often joins the lineage leading to the three murid rodents, so the rodents are no longer monophyletic. Apart from misplacing the root, the presence of the outgroups also distorts other parts of the unrooted tree. Either constraining the tree to maintain rodents monophyletic, or omitting murids, maintains the ingroup tree and sees the outgroup join on the edge to Xenarthra, to Afrotheria, or to these two groups together. This emphasises the importance of carrying out both an unrooted and a rooted analysis. It is known from cancer research that murid rodents have reduced activity in some DNA repair mechanisms and this alters their substitution pattern - this may be the case for mitochnodrial DNA as well. Comparing nucleotide compositions may identify taxa that differ in aspects of their DNA repair mechanisms.

  17. Population sex-ratio affecting behavior and physiology of overwintering bank voles (Myodes glareolus). (United States)

    Sipari, Saana; Haapakoski, Marko; Klemme, Ines; Palme, Rupert; Sundell, Janne; Ylönen, Hannu


    Many boreal rodents are territorial during the breeding season but during winter become social and aggregate for more energy efficient thermoregulation. Communal winter nesting and social interactions are considered to play an important role for the winter survival of these species, yet the topic is relatively little explored. Females are suggested to be the initiators of winter aggregations and sometimes reported to survive better than males. This could be due to the higher social tolerance observed in overwintering females than males. Hormonal status could also affect winter behavior and survival. For instance, chronic stress can have a negative effect on survival, whereas high gonadal hormone levels, such as testosterone, often induce aggressive behavior. To test if the winter survival of females in a boreal rodent is better than that of males, and to assess the role of females in the winter aggregations, we generated bank vole (Myodes glareolus) populations of three different sex ratios (male-biased, female-biased and even density) under semi-natural conditions. We monitored survival, spatial behavior and hormonal status (stress and testosterone) during two winter months. We observed no significant differences in survival between the sexes or among populations with differing sex-ratios. The degree of movement area overlap was used as an indicator of social tolerance and potential communal nesting. Individuals in male biased populations showed a tendency to be solitary, whereas in female biased populations there was an indication of winter aggregation. Females living in male-biased populations had higher stress levels than the females from the other populations. The female-biased sex-ratio induced winter breeding and elevated testosterone levels in males. Thus, our results suggest that the sex-ratio of the overwintering population can lead to divergent overwintering strategies in bank voles. Copyright © 2016 Elsevier Inc. All rights reserved.

  18. Excretion and measurement of corticosterone and testosterone metabolites in bank voles (Myodes glareolus). (United States)

    Sipari, Saana; Ylönen, Hannu; Palme, Rupert


    The bank vole is a commonly used model species in behavioral and ecophysiological studies. Thus, presenting a validated method for noninvasive monitoring of corticosterone and testosterone secretion is of high relevance. Here, we evaluated the effect of time of day and an ACTH challenge test on measured fecal corticosterone (FCM) and testosterone (FTM) metabolites in both sexes. Furthermore, we performed radiometabolism experiments for both steroids and sexes to study metabolism and excretion of (3)H-corticosterone and (3)H-testosterone. FCM and FTM were analysed with a 5α-pregnane-3β,11β,21-triol-20-one enzyme immunoassay (EIA) and a testosterone (measuring 17β-hydroxyandrostanes) EIA, respectively. Males had significantly higher FCM levels than females and their main excretion route was via the feces (∼72%), whereas females excreted nearly equal portions in both feces and urine. For testosterone the main excretion route was via the feces in both sexes (∼80%). The time course of excretion was similar in both sexes, but for the first time a significant difference between injected steroids was found: Corticosterone was excreted faster than testosterone, both in urine (median of peak levels: 4h vs 6h) and feces (6h vs 8h). Several metabolites were present in the feces and the tested EIAs reacted with some of them. Time of day had a significant effect on measured fecal steroid metabolites. As expected, males had significantly higher FTM levels than females. ACTH administration significantly increased FCM values; peaks were observed 4-8h after injection. In conclusion, both tested EIAs proved suited for a noninvasive measurement of glucocorticoids and androgens in bank voles. Copyright © 2016 Elsevier Inc. All rights reserved.

  19. Identification of subpopulations of prairie voles differentially susceptible to peer influence to decrease high alcohol intake

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    Allison M.J. Anacker


    Full Text Available Peer influences are critical in the decrease of alcohol (ethanol abuse and maintenance of abstinence. We previously developed an animal model of inhibitory peer influences on ethanol drinking using prairie voles and here sought to understand whether this influential behavior was due to specific changes in drinking patterns and to variation in a microsatellite sequence in the regulatory region of the vasopressin receptor 1a gene (avpr1a. Adult prairie voles’ drinking patterns were monitored in a lickometer apparatus that recorded each lick a subject exhibited during continuous access to water and 10% ethanol during periods of isolation, pair housing of high and low drinkers, and subsequent isolation. Analysis of fluid consumption confirmed previous results that high drinkers typically decrease ethanol intake when paired with low drinkers, but that a subset of voles do not decrease. Analysis of bout structure revealed differences in the number of ethanol drinking bouts in the subpopulations of high drinkers when paired with low drinkers. Lickometer drinking patterns analyzed by visual and by cross-correlation analyses demonstrated that pair housing did not increase the rate of subjects drinking in bouts occurring at the same time. The length of the avpr1a microsatellite did not predict susceptibility to peer influence or any other drinking behaviors. In summary, subpopulations of high drinkers were identified by fluid intake and number of drinking bouts, which did or did not lower their ethanol intake when paired with a low drinking peer, and these subpopulations should be explored for testing the efficacy of treatments to decrease ethanol use in groups that are likely to be responsive to different types of therapy.

  20. Identification of variables contributing to superovulation efficiency for production of transgenic prairie voles (Microtus ochrogaster). (United States)

    Keebaugh, Alaine C; Modi, Meera E; Barrett, Catherine E; Jin, Chengliu; Young, Larry J


    The prairie vole (Microtus ochrogaster) is an emerging animal model for biomedical research because of its rich sociobehavioral repertoire. Recently, lentiviral transgenic technology has been used to introduce the gene encoding the green fluorescent protein (GFP) into the prairie vole germline. However, the efficiency of transgenesis in this species is limited by the inability to reliably produce large numbers of fertilized embryos. Here we examined several factors that may contribute to variability in superovulation success including, age and parentage of the female, and latency to mating after being placed with the male. Females produced from 5 genetically distinct breeder lines were treated with 100 IU of pregnant mare serum gonadotrophin (PMSG) and immediately housed with a male separated by a perforated Plexiglas divider. Ovulation was induced 72 hr later with 30 IU of human chorionic gonadotropin (hCG) and 2 hrs later mating was allowed. Superovulation was most efficient in young females. For example, females aged 6-11 weeks produced more embryos (14 +/- 1.4 embryos) as compared to females aged 12-20 weeks (4 +/- 1.6 embryos). Females aged 4-5 weeks did not produce embryos. Further, females that mated within 15 min of male exposure produced significantly more embryos than those that did not. Interestingly, there was a significant effect of parentage. For example, 12 out of 12 females from one breeder pair superovulated (defined as producing 5 or more embryos), while only 2 out of 10 females for other lines superovulated. The results of this work suggest that age and genetic background of the female are the most important factors contributing to superovulation success and that latency to mating is a good predictor of the number of embryos to be recovered. Surprisingly we found that cohabitation with the male prior to mating is not necessary for the recovery of embryos but is necessary to recover oocytes. This information will dramatically reduce the number of

  1. Life-long shedding of Puumala hantavirus in wild bank voles (Myodes glareolus). (United States)

    Voutilainen, Liina; Sironen, Tarja; Tonteri, Elina; Bäck, Anne Tuiskunen; Razzauti, Maria; Karlsson, Malin; Wahlström, Maria; Niemimaa, Jukka; Henttonen, Heikki; Lundkvist, Åke


    The knowledge of viral shedding patterns and viraemia in the reservoir host species is a key factor in assessing the human risk of zoonotic viruses. The shedding of hantaviruses (family Bunyaviridae) by their host rodents has widely been studied experimentally, but rarely in natural settings. Here we present the dynamics of Puumala hantavirus (PUUV) shedding and viraemia in naturally infected wild bank voles (Myodes glareolus). In a monthly capture-mark-recapture study, we analysed 18 bank voles for the presence and relative quantity of PUUV RNA in the excreta and blood from 2 months before up to 8 months after seroconversion. The proportion of animals shedding PUUV RNA in saliva, urine and faeces peaked during the first month after seroconversion, but continued throughout the study period with only a slight decline. The quantity of shed PUUV in reverse transcription quantitative PCR (RT-qPCR) positive excreta was constant over time. In blood, PUUV RNA was present for up to 7 months but both the probability of viraemia and the virus load declined with time. Our findings contradict the current view of a decline in virus shedding after the acute phase and a short viraemic period in hantavirus infection - an assumption widely adopted in current epidemiological models. We suggest the life-long shedding as a means of hantaviruses to survive over host population bottlenecks, and to disperse in fragmented habitats where local host and/or virus populations face temporary extinctions. Our results indicate that the kinetics of pathogens in wild hosts may differ considerably from those observed in laboratory settings.

  2. Limits to sustained energy intake. XXIII. Does heat dissipation capacity limit the energy budget of lactating bank voles? (United States)

    Sadowska, Edyta T; Król, Elżbieta; Chrzascik, Katarzyna M; Rudolf, Agata M; Speakman, John R; Koteja, Paweł


    Understanding factors limiting sustained metabolic rate (SusMR) is a central issue in ecological physiology. According to the heat dissipation limit (HDL) theory, the SusMR at peak lactation is constrained by the maternal capacity to dissipate body heat. To test that theory, we shaved lactating bank voles (Myodes glareolus) to experimentally elevate their capacity for heat dissipation. The voles were sampled from lines selected for high aerobic exercise metabolism (A; characterized also by increased basal metabolic rate) and unselected control lines (C). Fur removal significantly increased the peak-lactation food intake (mass-adjusted least square means ± s.e.; shaved: 16.3 ± 0.3 g day(-1), unshaved: 14.4 ± 0.2 g day(-1); Plines. Thus, the experimental evolution model did not reveal a difference in the limiting mechanism between animals with inherently different metabolic rates.

  3. It is raining mice and voles: which weather conditions influence the activity of Apodemus flavicollis and Myodes glareolus?


    Wróbel, Aleksandra; Bogdziewicz, Michał


    Rodents constitute a crucial part of food chains in many ecosystems; thus, changes in their activity might influence many other species in the community. Moreover, daily variations in activity appear to be an important adaptation, helping rodents to cope with fluctuating intensity of predation pressure and food availability. We investigated how the nightly activity of the yellow-necked mouse (Apodemus flavicollis) and the bank vole (Myodes glareolus) changes with weather conditions. Increased...

  4. Male and female meadow voles Microtus pennsylvanicus respond differently to scent marks from the top- middle-, and bottom-scent donors of an over-mark

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    Michael H. FERKIN, Nicholas J. HOBBS, Benjamin D. FERKIN, Adam C.FERKIN, Daniel A. FERKIN


    Full Text Available Previous studies have shown that individuals responded preferentially to the mark of the top-scent donor relative to that of the bottom-scent donor of an over-mark. However, terrestrial mammals are likely to encounter over-marks consisting of the scent marks of more than two same-sex conspecifics in the intersections of runways, near the nests of sexually receptive female conspecifics, and inside and along the borders of the territories of conspecifics. We determined how meadow voles, Microtus pennsylvanicus, respond to the marks of the top-, middle-, and bottom-scent donors of an over-mark. We tested the hypothesis that voles exposed to an over-mark will respond preferentially to the scent marks that were deposited more recently, the scent marks that were on top or near the top of the over-mark, compared to the scent marks that were deposited earlier or near the bottom of the over-mark. Voles spent more time investigating the mark of the top-scent donor than that of the either the middle- or bottom-scent donor. However, males but not female voles spent more time investigating the middle-scent mark than the bottom-scent mark. We also tested the hypothesis that voles evaluate and respond to over-marks differently from single scent marks. Voles spent more time investigating the marks of the top-, middle-, and bottom-scent donors compared to scent marks that were not part of the over-mark. Voles can distinguish among the overlapping scent marks of three scent donors and sex differences exist in the values they appear to attach to each of these scent marks [Current Zoology 57 (4: 441–448, 2011].

  5. Effects of acute corticosterone treatment on male prairie voles (Microtus ochrogaster): Territorial aggression does not accompany induced social preference. (United States)

    Blondel, Dimitri V; Phelps, Steven M


    Corticosterone (CORT) is a stress-related steroid hormone found in vertebrates, and is known to interact with behavior. In the socially monogamous prairie vole (Microtus ochrogaster), acute stress and specifically acute CORT administration have been shown to facilitate male social preference for a familiar female, and this effect has been described as facilitation of the monogamous pair bond. It is possible, however, that the effects of stress on social preference may initially represent a short-term coping strategy. Here we test whether the effect of acute CORT administration extends to territoriality, a defining component of the prairie vole monogamous suite of behaviors. Onset of territoriality would provide further support for an induced pair bond, whereas no increase in aggression would suggest an initial coping response. Using acute exogenous CORT injections followed by behavioral trials, we found a facilitation of social preference, but we did not find increased aggression. This result suggests that the social preference that develops in response to CORT is at least in part a coping response rather than facilitation of comprehensive monogamous pair bond behavior. Our results are consistent with previous studies both within prairie voles and across other taxa that suggest that social contact may be involved in the regulation of stress responses. (PsycINFO Database Record (c) 2016 APA, all rights reserved).

  6. Re-feeding food-deprived male meadow voles affects the sperm allocation of their rival males. (United States)

    Vaughn, Ashlee A; Delbarco-Trillo, Javier; Ferkin, Michael H


    An individual's nutritional status affects the manner in which same- and opposite-sex conspecifics respond to that individual, which may affect their fitness. Male meadow voles, Microtus pennsylvanicus, increase their sperm allocation if they encounter the scent mark of an unfamiliar male that is not nutritionally challenged. If, however, the scent mark comes from a male that has been food deprived for 24 hours, stud male voles do not increase their sperm allocation. Food deprived males may be viewed as being lower quality and a reduced risk of sperm competition by rival males. We hypothesized that stud males in promiscuous mating systems tailor their sperm allocations depending on whether rival males have been food deprived and then re-fed. We predicted that newly re-fed males will be considered a strong risk of sperm competition because of the potentially high fitness and survival costs associated with food deprivation in males, and that they will cause stud males to increase their sperm allocation. Our results, however, showed that the recovery period from 24 hours of food deprivation was a relatively slow process. It took between 96 hours and 336 hours of re-feeding male scent donors that were food deprived for 24 hours to induce stud males to increase their sperm allocation to levels comparable to when scent donors were not food deprived. Stud male voles may be conserving the amount of sperm allocated until the male scent donors have recovered from food deprivation and subsequent re-feeding.

  7. Photoperiod-Dependent Effects of 4-tert-Octylphenol on Adherens and Gap Junction Proteins in Bank Vole Seminiferous Tubules

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    Anna Hejmej


    Full Text Available In the present study we evaluated in vivo and in vitro effects of 4-tert-octylphenol (OP on the expression and distribution of adherens and gap junction proteins, N-cadherin, β-catenin, and connexin 43 (Cx43, in testes of seasonally breeding rodents, bank voles. We found that in bank vole testes expression and distribution of N-cadherin, β-catenin, and Cx43 were photoperiod dependent. Long-term treatment with OP (200 mg/kg b.w. resulted in the reduction of junction proteins expressions (P<0.05, P<0.01 and their delocalization in the testes of males kept in long photoperiod, whereas in short-day animals slight increase of Cx43 (P<0.05, N-cadherin, and β-catenin (statistically nonsignificant levels was observed. Effects of OP appeared to be independent of FSH and were maintained during in vitro organ culture, indicating that OP acts directly on adherens and gap junction proteins in the testes. An experiment performed using an antiestrogen ICI 182,780 demonstrated that the biological effects of OP on β-catenin and Cx43 involve an estrogen receptor-mediated response. Taken together, in bank vole organization of adherens and gap junctions and their susceptibility to OP are related to the length of photoperiod. Alterations in cadherin/catenin and Cx43-based junction may partially result from activation of estrogen receptor α and/or β signaling pathway.

  8. Microevolution of Puumala hantavirus during a complete population cycle of its host, the bank vole (Myodes glareolus.

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    Maria Razzauti

    Full Text Available Microevolution of Puumala hantavirus (PUUV was studied throughout a population cycle of its host, the bank vole (Myodes glareolus. We monitored PUUV variants circulating in the host population in Central Finland over a five-year period that included two peak-phases and two population declines. Of 1369 bank voles examined, 360 (26.3% were found infected with PUUV. Partial sequences of each of the three genome segments were recovered (approx. 12% of PUUV genome from 356 bank voles. Analyses of these sequences disclosed the following features of PUUV evolution: 1 nucleotide substitutions are mostly silent and deduced amino acid changes are mainly conservative, suggesting stabilizing selection at the protein level; 2 the three genome segments accumulate mutations at a different rate; 3 some of the circulating PUUV variants are frequently observed while others are transient; 4 frequently occurring PUUV variants are composed of the most abundant segment genotypes (copious and new transient variants are continually generated; 5 reassortment of PUUV genome segments occurs regularly and follows a specific pattern of segments association; 6 prevalence of reassortant variants oscillates with season and is higher in the autumn than in the spring; and 7 reassortants are transient, i.e., they are not competitively superior to their parental variants. Collectively, these observations support a quasi-neutral mode of PUUV microevolution with a steady generation of transient variants, including reassortants, and preservation of a few preferred genotypes.

  9. Soil removed by voles of the genus Pitymys in the Spanish Pyrenees

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    Borghi, C. E.


    Full Text Available The erosiogenic activity of Pyrenean mountain voles is studied following the measures taken in an experimental plot in the Western Pyrenees. An easy model for estimating the volume and weight of soil carried to the surface by voles is presented and used to quantify this amount in natural conditions. Fossorial Pyrenean rodents seem to dislodge well over 6Tm/ha.yr of soil on the colonized areas above the timberline. The four stages (new, recent, old, and vegetated of the evolution of soil heaps are discussed. Finally, an attempt is made to evaluate the rate of horizontal sediment transport due to the direct action of voles, with a maximum result of 17 cm3/cm.yr, quite comparable to pure geoclimatic rates.

    [es] Se estudia la actividad de movimiento del suelo de los roedores pirenaicos del género Pitymys, a partir de los datos obtenidos en una parcela experimental situada en los Pirineos Occidentales. Se presenta un modelo sencillo para estimar la cantidad de tierra removida a partir de medidas que pueden tomarse fácilmente en el campo, y se emplea dicho modelo para evaluar esta magnitud en condiciones naturales. Al parecer, los roedores subterráneos pueden sacar al exterior más de 6 Tm de tierra por hectárea y año en las zonas epiforestales que colonizan. También se discute la evolución del suelo removido y sus condiciones para la erosión por escorrentía. Finalmente se intenta evaluar la tasa de transporte horizontal del sedimento debida a los animales, que resulta ser de hasta 17 cm3 por cm y año, un valor claramente comparable con los debidos a agentes geoclimáticos.
    [fr] On a étudié l'activité fouisseuse des campagnols pyrénéens du genre Pitymys, d'après les données recueillies dans une enclosure expérimentale située dans les Pyrénées de l'Ouest. On présente un modèle simple permettant d'estimer la quantité de sol mue par les campagnols a partir de mésurements qu

  10. Adler hantavirus, a new genetic variant of Tula virus identified in Major's pine voles (Microtus majori) sampled in southern European Russia. (United States)

    Tkachenko, Evgeniy A; Witkowski, Peter T; Radosa, Lukas; Dzagurova, Tamara K; Okulova, Nataliya M; Yunicheva, Yulia V; Vasilenko, Ludmila; Morozov, Vyacheslav G; Malkin, Gennadiy A; Krüger, Detlev H; Klempa, Boris


    Although at least 30 novel hantaviruses have been recently discovered in novel hosts such as shrews, moles and even bats, hantaviruses (family Bunyaviridae, genus Hantavirus) are primarily known as rodent-borne human pathogens. Here we report on identification of a novel hantavirus variant associated with a rodent host, Major's pine vole (Microtus majori). Altogether 36 hantavirus PCR-positive Major's pine voles were identified in the Krasnodar region of southern European Russia within the years 2008-2011. Initial partial L-segment sequence analysis revealed novel hantavirus sequences. Moreover, we found a single common vole (Microtusarvalis) infected with Tula virus (TULV). Complete S- and M-segment coding sequences were determined from 11 Major's pine voles originating from 8 trapping sites and subjected to phylogenetic analyses. The data obtained show that Major's pine vole is a newly recognized hantavirus reservoir host. The newfound virus, provisionally called Adler hantavirus (ADLV), is closely related to TULV. Based on amino acid differences to TULV (5.6-8.2% for nucleocapsid protein, 9.4-9.5% for glycoprotein precursor) we propose to consider ADLV as a genotype of TULV. Occurrence of ADLV and TULV in the same region suggests that ADLV is not only a geographical variant of TULV but a host-specific genotype. High intra-cluster nucleotide sequence variability (up to 18%) and geographic clustering indicate long-term presence of the virus in this region.

  11. Identification of variables contributing to superovulation efficiency for production of transgenic prairie voles (Microtus ochrogaster

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    Keebaugh Alaine C


    Full Text Available Abstract Background The prairie vole (Microtus ochrogaster is an emerging animal model for biomedical research because of its rich sociobehavioral repertoire. Recently, lentiviral transgenic technology has been used to introduce the gene encoding the green fluorescent protein (GFP into the prairie vole germline. However, the efficiency of transgenesis in this species is limited by the inability to reliably produce large numbers of fertilized embryos. Here we examined several factors that may contribute to variability in superovulation success including, age and parentage of the female, and latency to mating after being placed with the male. Methods Females produced from 5 genetically distinct breeder lines were treated with 100 IU of pregnant mare serum gonadotrophin (PMSG and immediately housed with a male separated by a perforated Plexiglas divider. Ovulation was induced 72 hr later with 30 IU of human chorionic gonadotropin (hCG and 2 hrs later mating was allowed. Results Superovulation was most efficient in young females. For example, females aged 6-11 weeks produced more embryos (14 +/- 1.4 embryos as compared to females aged 12-20 weeks (4 +/- 1.6 embryos. Females aged 4-5 weeks did not produce embryos. Further, females that mated within 15 min of male exposure produced significantly more embryos than those that did not. Interestingly, there was a significant effect of parentage. For example, 12 out of 12 females from one breeder pair superovulated (defined as producing 5 or more embryos, while only 2 out of 10 females for other lines superovulated. Conclusions The results of this work suggest that age and genetic background of the female are the most important factors contributing to superovulation success and that latency to mating is a good predictor of the number of embryos to be recovered. Surprisingly we found that cohabitation with the male prior to mating is not necessary for the recovery of embryos but is necessary to recover

  12. Reproduction, aging and mortality rate in social subterranean mole voles (Ellobius talpinus Pall.). (United States)

    Novikov, E; Kondratyuk, E; Petrovski, D; Titova, T; Zadubrovskaya, I; Zadubrovskiy, P; Moshkin, M


    Eusocial subterranean rodents of the Bathyergidae family have enormous longevity. The long lifespan of these species is associated with negligible senescence, that is, an absence of the signs of age-related deterioration in physical condition. The question arises as to whether these features are unique to eusocial Bathyergids or typical of other social subterranean rodents as well. In the present study, we analysed data from observations of a social subterranean Microtinae rodent, the northern mole vole (Ellobius talpinus Pall.), which, like mole-rats, has reproductive skew. Among the individuals captured in the wild and maintained in captivity, females that reproduced lived significantly longer than non-breeding females. We did not find any changes in muscle strength with age in any of the demographic groups studied. Faecal glucocorticoid concentrations before death were significantly higher in non-breeding females than in breeding females and males. Increased adrenocortical activity may be one mechanism responsible for the decreased lifespan of non-reproducing individuals of social subterranean rodents. We conclude that the patterns of aging, although different in some respects, are generally common for social subterranean rodents of different taxonomic groups.

  13. Description of Paranoplocephala etholeni n. sp. (Cestoda: Anoplocephalidae in the meadow vole Microtus pennsylvanicus, with a synopsis of Paranoplocephala s. l. in Holarctic rodents

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    Haukisalmi V.


    Full Text Available Paranoplocephala etholeni n. sp., parasitizing the meadow vole Microtus pennsylvanicus in Alaska and Wisconsin, USA is described. Paranoplocephala etholeni is morphologically most closely related to the Nearctic Paranoplocephala ondatrae (Rausch, 1948. Available data suggest that P. etholeni is a host-specific, locally rare species that may have a wide but sporadic geographical distribution in North America. The finding of P. ondatrae-like cestodes in Microtus spp. suggests that this poorly known species may actually be a parasite of voles rather than muskrat (type host. A tabular synopsis of all the known species of Paranoplocephala s. l. in the Holarctic region with their main morphological features is presented.

  14. Population, Environmental, and Community Effects on Local Bank Vole (Myodes glareolus) Puumala Virus Infection in an Area with Low Human Incidence

    DEFF Research Database (Denmark)

    Tersago, K; Schreurs, A; Linard, C


    regard the combination of a dilution effect, a possible threshold density that depends on local conditions, and a higher fragmentation of suitable bank vole habitat in our study area as plausible explanations for the sparse occurrence of PUUV infection and low prevalence detected. Thus, beside human...... habitat and tested for anti-PUUV IgG. Infection data were related to individual bank vole features, population demography, and environmental variables. Rare occurrence of PUUV infection was found and PUUV prevalence was low compared with data from the high NE incidence area in southern Belgium. Small...

  15. Captive housing during water vole (Arvicola terrestris reintroduction: does short-term social stress impact on animal welfare?

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    Merryl Gelling

    Full Text Available BACKGROUND: Animals captive bred for reintroduction are often housed under conditions which are not representative of their preferred social structure for at least part of the reintroduction process. Specifically, this is most likely to occur during the final stages of the release programme, whilst being housed during transportation to the release site. The degree of social stress experienced by individuals during this time may negatively impact upon their immunocompetence. METHODOLOGY/PRINCIPAL FINDINGS: We examined two measure of stress--body weight and Leukocyte Coping Capacity (LCC--to investigate the effects of group size upon captive-bred water voles destined for release within a reintroduction program. Water voles were housed in laboratory cages containing between one and eight individuals. LCC scores were negatively correlated with group size, suggesting that individuals in larger groups experienced a larger degree of immuno-suppression than did individuals housed in smaller groups or individually. During the course of the study mean body weights increased, in contrast to expectations from a previous study. This was attributed to the individuals sampled being sub-adults and thus growing in length and weight during the course of the investigation. CONCLUSIONS/SIGNIFICANCE: The reintroduction process will inevitably cause some stress to the release cohort. However, for water voles we conclude that the stress experienced may be reduced by decreasing group size within captive colony and/or transportation housing practises. These findings are of significance to other species' reintroductions, in highlighting the need to consider life-history strategies when choosing housing systems for animals being maintained in captivity prior to release to the wild. A reduction in stress experienced at the pre-release stage may improve immunocompetence and thus animal welfare and initial survival post-release.

  16. Woodland recovery after suppression of deer: cascade effects for small mammals, wood mice (Apodemus sylvaticus and bank voles (Myodes glareolus.

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    Emma R Bush

    Full Text Available Over the past century, increases in both density and distribution of deer species in the Northern Hemisphere have resulted in major changes in ground flora and undergrowth vegetation of woodland habitats, and consequentially the animal communities that inhabit them. In this study, we tested whether recovery in the vegetative habitat of a woodland due to effective deer management (from a peak of 0.4-1.5 to <0.17 deer per ha had translated to the small mammal community as an example of a higher order cascade effect. We compared deer-free exclosures with neighboring open woodland using capture-mark-recapture (CMR methods to see if the significant difference in bank vole (Myodes glareolus and wood mouse (Apodemus sylvaticus numbers between these environments from 2001-2003 persisted in 2010. Using the multi-state Robust Design method in program MARK we found survival and abundance of both voles and mice to be equivalent between the open woodland and the experimental exclosures with no differences in various metrics of population structure (age structure, sex composition, reproductive activity and individual fitness (weight, although the vole population showed variation both locally and temporally. This suggests that the vegetative habitat--having passed some threshold of complexity due to lowered deer density--has allowed recovery of the small mammal community, although patch dynamics associated with vegetation complexity still remain. We conclude that the response of small mammal communities to environmental disturbance such as intense browsing pressure can be rapidly reversed once the disturbing agent has been removed and the vegetative habitat is allowed to increase in density and complexity, although we encourage caution, as a source/sink dynamic may emerge between old growth patches and the recently disturbed habitat under harsh conditions.

  17. Morphological diversity of mole vole mono- and polymorphic populations: Does Chernov's "compensation principle" work within a population? (United States)

    Vasil'ev, A G; Bolshakov, V N; Evdokimov, N G; Sineva, N V


    The ecological "compensation principle" enunciated by Yu.I. Chernov, who suggested a higher level of compensatory diversity in communities depleted in composition, proved to be also applicable to a single population, as demonstrated in a model rodent species, mole vole with mono- and polymorphic coat color, using the methods of geometric morphometrics. The mandible shape diversity was significantly increased in the monomorphic as compared to polymorphic populations, in which the division of foraging activities between animals of different morphs led to a suppression of general morphological diversity.

  18. Litter size variation in hypothalamic gene expression determines adult metabolic phenotype in Brandt's voles (Lasiopodomys brandtii.

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    Xue-Ying Zhang

    Full Text Available BACKGROUND: Early postnatal environments may have long-term and potentially irreversible consequences on hypothalamic neurons involved in energy homeostasis. Litter size is an important life history trait and negatively correlated with milk intake in small mammals, and thus has been regarded as a naturally varying feature of the early developmental environment. Here we investigated the long-term effects of litter size on metabolic phenotype and hypothalamic neuropeptide mRNA expression involved in the regulation of energy homeostasis, using the offspring reared from large (10-12 and small (3-4 litter sizes, of Brandt's voles (Lasiopodomys brandtii, a rodent species from Inner Mongolia grassland in China. METHODOLOGY/PRINCIPAL FINDINGS: Hypothalamic leptin signaling and neuropeptides were measured by Real-Time PCR. We showed that offspring reared from small litters were heavier at weaning and also in adulthood than offspring from large litters, accompanied by increased food intake during development. There were no significant differences in serum leptin levels or leptin receptor (OB-Rb mRNA in the hypothalamus at weaning or in adulthood, however, hypothalamic suppressor of cytokine signaling 3 (SOCS3 mRNA in adulthood increased in small litters compared to that in large litters. As a result, the agouti-related peptide (AgRP mRNA increased in the offspring from small litters. CONCLUSIONS/SIGNIFICANCE: These findings support our hypothesis that natural litter size has a permanent effect on offspring metabolic phenotype and hypothalamic neuropeptide expression, and suggest central leptin resistance and the resultant increase in AgRP expression may be a fundamental mechanism underlying hyperphagia and the increased risk of overweight in pups of small litters. Thus, we conclude that litter size may be an important and central determinant of metabolic fitness in adulthood.

  19. Intergenerational transmission of alloparental behavior and oxytocin and vasopressin receptor distribution in the prairie vole

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    Allison M Perkeybile


    Full Text Available Variation in the early environment has the potential to permanently alter offspring behavior and development. We have previously shown that naturally occurring variation in biparental care of offspring in the prairie vole is related to differences in social behavior of the offspring. It was not, however, clear whether the behavioral differences seen between offspring receiving high compared to low amounts of parental care were the result of different care experiences or were due to shared genetics with their high-contact or low-contact parents. Here we use cross-fostering methods to determine the mode of transmission of alloparental behavior and oxytocin receptor (OTR and vasopressin V1a receptor (V1aR binding from parent to offspring. Offspring were cross-fostered or in-fostered on postnatal day 1 and parental care received was quantified in the first week postpartum. At weaning, offspring underwent an alloparental care test and brains were then collected from all parents and offspring to examine OTR and V1aR binding. Results indicate that alloparental behavior of offspring was predicted by the parental behavior of their rearing parents. Receptor binding for both OTR and V1aR tended to be predicted by the genetic mothers for female offspring and by the genetic fathers for male offspring. These findings suggest a different role of early experience and genetics in shaping behavior compared to receptor distribution and support the notion of sex-dependent outcomes, particularly in the transmission of receptor binding patterns.

  20. Organismal effects of pesticide exposure on meadow voles (Microtus pennsylvanicus) living in golf course ecosystems: developmental instability, clinical hematology, body condition, and blood parasitology. (United States)

    Knopper, Loren D; Mineau, Pierre


    This is the second of two articles reporting the results of a nonlethal biomonitoring study that quantified the effects of pesticide exposure on meadow voles (Microtus pennsylvanicus) living in golf course ecosystems of the Ottawa/Gatineau region (ON and PQ, Canada, respectively). In the present article, we describe results of measurements regarding developmental instability (e.g., fluctuating asymmetry), congenital birth defects (e.g., skeletal terata), clinical hematology (e.g., differential counts), general body condition (e.g., body mass-length relationships), and blood parasite load (Trypanosoma sp. and Bartonella spp.). Voles were captured during the year 2001 to 2003 at six golf courses and two reference sites. Once voles were fully sedated using isoflurane, blood was collected, radiographs taken, and morphometric measurements recorded. Three animals from each course were euthanized to determine body burdens of historically used organochlorine (OC) and metal-based pesticides. Exposure to in-use pesticides was determined from detailed golf course pesticide-use records. None of the endpoints measured was significantly related to body burdens of OC pesticides and metals historically used, nor did any endpoint significantly vary among capture sites in relation to total pesticide application to the capture site or to the number of days since the last application of pesticide. Based on these findings, it appears that voles from golf courses were no less healthy than their conspecifics from reference sites.

  1. Bank Vole Prion Protein As an Apparently Universal Substrate for RT-QuIC-Based Detection and Discrimination of Prion Strains.

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    Christina D Orrú


    Full Text Available Prions propagate as multiple strains in a wide variety of mammalian species. The detection of all such strains by a single ultrasensitive assay such as Real Time Quaking-induced Conversion (RT-QuIC would facilitate prion disease diagnosis, surveillance and research. Previous studies have shown that bank voles, and transgenic mice expressing bank vole prion protein, are susceptible to most, if not all, types of prions. Here we show that bacterially expressed recombinant bank vole prion protein (residues 23-230 is an effective substrate for the sensitive RT-QuIC detection of all of the different prion types that we have tested so far--a total of 28 from humans, cattle, sheep, cervids and rodents, including several that have previously been undetectable by RT-QuIC or Protein Misfolding Cyclic Amplification. Furthermore, comparison of the relative abilities of different prions to seed positive RT-QuIC reactions with bank vole and not other recombinant prion proteins allowed discrimination of prion strains such as classical and atypical L-type bovine spongiform encephalopathy, classical and atypical Nor98 scrapie in sheep, and sporadic and variant Creutzfeldt-Jakob disease in humans. Comparison of protease-resistant RT-QuIC conversion products also aided strain discrimination and suggested the existence of several distinct classes of prion templates among the many strains tested.

  2. Bank Vole Prion Protein As an Apparently Universal Substrate for RT-QuIC-Based Detection and Discrimination of Prion Strains. (United States)

    Orrú, Christina D; Groveman, Bradley R; Raymond, Lynne D; Hughson, Andrew G; Nonno, Romolo; Zou, Wenquan; Ghetti, Bernardino; Gambetti, Pierluigi; Caughey, Byron


    Prions propagate as multiple strains in a wide variety of mammalian species. The detection of all such strains by a single ultrasensitive assay such as Real Time Quaking-induced Conversion (RT-QuIC) would facilitate prion disease diagnosis, surveillance and research. Previous studies have shown that bank voles, and transgenic mice expressing bank vole prion protein, are susceptible to most, if not all, types of prions. Here we show that bacterially expressed recombinant bank vole prion protein (residues 23-230) is an effective substrate for the sensitive RT-QuIC detection of all of the different prion types that we have tested so far--a total of 28 from humans, cattle, sheep, cervids and rodents, including several that have previously been undetectable by RT-QuIC or Protein Misfolding Cyclic Amplification. Furthermore, comparison of the relative abilities of different prions to seed positive RT-QuIC reactions with bank vole and not other recombinant prion proteins allowed discrimination of prion strains such as classical and atypical L-type bovine spongiform encephalopathy, classical and atypical Nor98 scrapie in sheep, and sporadic and variant Creutzfeldt-Jakob disease in humans. Comparison of protease-resistant RT-QuIC conversion products also aided strain discrimination and suggested the existence of several distinct classes of prion templates among the many strains tested.

  3. Cold exposure inhibits hypothalamic Kiss-1 gene expression, serum leptin concentration, and delays reproductive development in male Brandt's vole ( Lasiopodomys brandtii) (United States)

    Zhang, Qiang; Lin, Yi; Zhang, Xue-Ying; Wang, De-Hua


    Cold commonly affects growth and reproductive development in small mammals. Here, we test the hypothesis that low ambient temperature will affect growth and puberty onset, associated with altered hypothalamic Kiss-1 gene expression and serum leptin concentration in wild rodents. Male Brandt's voles ( Lasiopodomys brandtii) were exposed to cold (4 ± 1 °C) and warm (23 ± 1 °C) conditions from the birth and sacrificed on different developmental stages (day 26, day 40, day 60, and day 90, respectively). Brandt's voles increased the thermogenic capacity of brown adipose tissue, mobilized body fat, decreased serum leptin levels, and delayed the reproductive development especially on day 40 in the cold condition. They increased food intake to compensate for the high energy demands in the cold. The hypothalamic Kiss-1 gene expression on day 26 was decreased, associated with lower wet testis mass and testis testosterone concentration on day 40, in the cold-exposed voles compared to that in the warm. Serum leptin was positively correlated with body fat, testis mass, and testosterone concentration. These data suggested that cold exposure inhibited hypothalamic Kiss-1 gene expression during the early stage of development, decreased serum leptin concentration, and delayed reproductive development in male Brandt's voles.

  4. Increased radiation from Chernobyl decreases the expression of red colouration in natural populations of bank voles (Myodes glareolus). (United States)

    Boratyński, Zbyszek; Lehmann, Philipp; Mappes, Tapio; Mousseau, Timothy A; Møller, Anders Pape


    Pheomelanin is a pink to red version of melanin pigment deposited in skin and hair. Due to its bright colour, pheomelanin plays a crucial function in signalling, in particular sexual signalling. However, production of pheomelanin, as opposed to its dark alternative, eumelanin, bears costs in terms of consumption of antioxidants important for protection of DNA against naturally produced reactive oxidative species. Therefore, decreased expression of pheomelanin is expected in organisms exposed to severe oxidative stress such as that caused by exposure to chronic ionizing radiation. We tested if variable exposure to radiation among natural populations of bank voles Myodes glareolus in Chernobyl affected expression of red colouration in their dorsal fur. The relative redness of dorsal fur was positively correlated with weight, but also negatively correlated with the level of background radiation. These results suggest that the development of the natural red colouration in adult bank voles is affected by ionizing background radiation, and potentially causing elevated levels of oxidative stress. Reduced production of pheomelanin allows more antioxidants to mitigate the oxidative stress caused by radiation. However, changing natural animal colouration for physiological reasons can have ecological costs, if e.g. it causes mismatch with habitat colouration and conspicuousness for predators.

  5. Between the Balkans and the Baltic: Phylogeography of a Common Vole Mitochondrial DNA Lineage Limited to Central Europe (United States)

    Stojak, Joanna; McDevitt, Allan D.; Herman, Jeremy S.; Kryštufek, Boris; Uhlíková, Jitka; Purger, Jenő J.; Lavrenchenko, Leonid A.; Searle, Jeremy B.; Wójcik, Jan M.


    The common vole (Microtus arvalis) has been a model species of small mammal for studying end-glacial colonization history. In the present study we expanded the sampling from central and eastern Europe, analyzing contemporary genetic structure to identify the role of a potential ‘northern glacial refugium’, i.e. a refugium at a higher latitude than the traditional Mediterranean refugia. Altogether we analyzed 786 cytochrome b (cytb) sequences (representing mitochondrial DNA; mtDNA) from the whole of Europe, adding 177 new sequences from central and eastern Europe, and we conducted analyses on eight microsatellite loci for 499 individuals (representing nuclear DNA) from central and eastern Europe, adding data on 311 new specimens. Our new data fill gaps in the vicinity of the Carpathian Mountains, the potential northern refugium, such that there is now dense sampling from the Balkans to the Baltic Sea. Here we present evidence that the Eastern mtDNA lineage of the common vole was present in the vicinity of this Carpathian refugium during the Last Glacial Maximum and the Younger Dryas. The Eastern lineage expanded from this refugium to the Baltic and shows low cytb nucleotide diversity in those most northerly parts of the distribution. Analyses of microsatellites revealed a similar pattern but also showed little differentiation between all of the populations sampled in central and eastern Europe. PMID:27992546

  6. From home range dynamics to population cycles: validation and realism of a common vole population model for pesticide risk assessment. (United States)

    Wang, Magnus


    Despite various attempts to establish population models as standard tools in pesticide risk assessment, population models still receive limited acceptance by risk assessors and authorities in Europe. A main criticism of risk assessors is that population models are often not, or not sufficiently, validated. Hence the realism of population-level risk assessments conducted with such models remains uncertain. We therefore developed an individual-based population model for the common vole, Microtus arvalis, and demonstrate how population models can be validated in great detail based on published data. The model is developed for application in pesticide risk assessment, therefore, the validation covers all areas of the biology of the common vole that are relevant for the analysis of potential effects and recovery after application of pesticides. Our results indicate that reproduction, survival, age structure, spatial behavior, and population dynamics reproduced from the model are comparable to field observations. Also interannual population cycles, which are frequently observed in field studies of small mammals, emerge from the population model. These cycles were shown to be caused by the home range behavior and dispersal. As observed previously in the field, population cycles in the model were also stronger for longer breeding season length. Our results show how validation can help to evaluate the realism of population models, and we discuss the importance of taking field methodology and resulting bias into account. Our results also demonstrate how population models can help to test or understand biological mechanisms in population ecology.

  7. Time-course of micronucleated erythrocytes in response to whole-body gamma irradiation in a model mammalian species, the bank vole (Clethrionomys glareolus, Schreber). (United States)

    Smolich, Igor I; Savina, Natalya V; Ryabokon, Nadezhda I


    The time course of the formation of micronucleated polychromatic (MNPCEs) and normochromatic erythrocytes (MNNCEs) in the bone marrow of the bank vole (Clethrionomys glareolus, Schreber), a model mouse-like species, was studied using the standard micronucleus test at 0, 6, 12, 18, 24, 30, 36 and 48 hr following whole-body acute γ-irradiation at a dose of 0.5 Gy. Based on the existing literature on laboratory mice, it was suggested that such a dose will not have significant effect on erythroid cell proliferation in the bank vole and hence on the time course of the rise of micronucleated cells. In total, ∼905,000 polychromatic (PCEs) and normochromatic erythrocytes (NCEs) from 82 adult bank voles were analyzed. Although the mean frequencies of MNNCEs were too low to allow for the correct assessment of their time course, an analysis of PCEs showed an increasing rate of MNPCE appearance at 6 hr that reached a maximum at 18-24 hr after irradiation and subsequently decreased. Because the kinetics of MNPCEs reflects the process of erythropoiesis, the current results regarding the time points of appearance of radiation-induced MNPCEs provide the first information on the prolongation of one of the terminal stages of erythrocyte formation in bank vole specimens, namely the stage of maturation of PCEs from erythroblasts. Moreover, the observed time-course data, as well as the low-background frequencies of MNPCEs and characteristic level of PCEs response to radiation, showed similarities between the two model species: bank vole (this study) and laboratory mice (literature data).

  8. Time series analysis performed on nephropathia epidemica in humans of northern Sweden in relation to bank vole population dynamic and the NAO index. (United States)

    Palo, R Thomas


    Time series analysis was performed on two data series of human nephropathia epidemica (NE) infections in northern Sweden between the years 1959-1975 and 1985-2006. The analysis confirms that the bank vole (Myodes glareolus), the main reservoir species, shows regular peaks in population density approximately every fourth year. The periodicity in NE cases of the more recent time period (1985-2006) is 2.8-3.3 years and the older period shows a periodicity ranging 3.4-4.2 years, but this is not significantly different from that expected by vole dynamics. A comparison of North Atlantic Oscillation (NAO) index between the two periods reveals higher mean winter NAO index in the period 1985-2006 than in 1959-1975. No difference was found in frequency of the NAO index between the older period (2.8-3.4 years) compared with the recent period (2.4-2.8 years). Cross-correlation revealed a delayed effect by NAO index on vole abundance but a multivariate model showed that NAO index did not explain the variation in NE cases. Vole index was the only factor that contributed significantly to the variation in numbers of NE cases and that no climate effect could be detected. The climate signal from NAO index does not appear to significantly affect the human NE cases and this suggests that the transmission of disease to man is not particularly sensitive to variations in weather factors. The results favour the hypothesis that higher NAO index will not increase the likelihood of virus transmission from voles to man in northern Sweden under present climatic conditions.

  9. The role of the water voles (Arvicola, Rodentia in the Quatemary

    Directory of Open Access Journals (Sweden)

    Ruiz Bustos, A.


    Full Text Available Arvicolids are rodents which have molars with a morphology formed by a sequence of enamel folds similar to the curve y = sin f(x. The morphology of the crown of the first lower molar (mi of living species of Arvicola (large voles is identified with six criteria, irrespective of tooth size. When rootless arvicolid fossil communities are analysed, it can be seen that the mi morphology of Arvicola is present in those communities represented by specimens of small size at the beginning of the Quaternary. Before this data was known, the presence of Arvicola communities could only be detected in the second half of the Quaternary, when the specimens were comparable to the large size characterising living species. The existence of communities of small-sized Arvicola at the beginning of the Quaternary implies that the mi of Arvicola undergoes a continuous and accelerated growth throughout the entire Quatemary, which allows representatives the genus to be used as a chronological tool. These data mean that it is necessary to change the concept of the genus Allophaiomys and to formulate a new classification to reflect evolutionary relationships of quatemary arvicolids.Los arvicólidos son roedores que tienen la morfología de la corona de los dientes formada por una secuencia de pliegues de esmalte que se asemeja a la curva y=sen f(x. Las especies actuales del género Arvicola cumplen en la morfología del molar mI, seis criterios que son independientes de la talla. El examen de las poblaciones de arvicólidos sin raíz, procedentes del Pleistoceno inferior, indica la existencia de molares con una morfología idéntica a la de los ejemplares vivos de Arvicola, pero con menor talla. La existencia de esta identidad permite proponer la hipótesis de poblaciones primitivas del género Arvicola con pequeña talla durante el Pleistoceno Inferior. Estas han pasado desapercibidas entre las poblaciones de Allophaiomys. a causa de su identidad morfológica entre ambos

  10. Selective predation of tawny owls (Strix aluco) on yellow-necked mice (Apodemus flavicollis) and bank voles (Myodes glareolus)

    DEFF Research Database (Denmark)

    Sunde, Peter; Forsom, Heidi Malene; Al-Sabi, Mohammad Nafi Solaiman


    Differential predation on certain classes of individuals within prey populations might make owls strong selective agents on their prey. We investigated selective predation of tawny owls (Strix aluco) on yellow-necked mice (Apodemus flavicollis, A.f.) and bank voles (Myodes glareolus, M.g.) for two...... years by comparing prey from owl nests with live-trapped individuals. The owls killed significantly more male M.g. (73%) than females, but not more than expected from traps (57%). For A.f., owls selected adults in favour of subadults, and for adults, individuals with longer femurs. Adult males of A.......f. killed by owls had significantly heavier testes in relation their size than the trapped males. Prey selection did not correlate with size-adjusted body or spleen mass. Owl-killed A.f. had higher prevalences of the intestinal helminth Heligmosomoides sp. than trapped individuals, but hosted similar...

  11. Selective Predation of Tawny Owls (Strix aluco) on Yellow-Necked Mice (Apodemus flavicollis) and Bank Voles (Myodes glareolus)

    DEFF Research Database (Denmark)

    Sunde, Peter; Forsom, Heidi Malene; Al-Sabi, Mohammad Nafi Solaiman


    Differential predation on certain classes of individuals within prey populations might make owls strong selective agents on their prey. We investigated selective predation of tawny owls (Strix aluco) on yellow-necked mice (Apodemus flavicollis, A.f.) and bank voles (Myodes glareolus, M.g.) for two...... years by comparing prey from owl nests with live-trapped individuals. The owls killed significantly more male M.g. (73%) than females, but not more than expected from traps (57%). For A.f., owls selected adults in favour of subadults, and for adults, individuals with longer femurs. Adult males of A.......f. killed by owls had significantly heavier testes in relation their size than the trapped males. Prey selection did not correlate with size-adjusted body or spleen mass. Owl-killed A.f. had higher prevalences of the intestinal helminth Heligmosomoides sp. than trapped individuals, but hosted similar...

  12. Vole Population Fluctuations: Why and When?%田鼠种群波动的原因和时间

    Institute of Scientific and Technical Information of China (English)

    Lowell L. Getz


    本文总结了橙腹田鼠(Microtus ochrogaster)和草原田鼠(M. pennsylvanicus)25年的种群统计学研究结果和结论.探讨了田鼠种群波动周期性、诱发种群波动以及导致波动期间峰值变异的因素.并对种群存活值和繁殖活动的作用进行了分析和评价.根据两种田鼠种群波动周期性、波动峰值出现的时间以及特定年份峰值的高度等特征,证明两物种波动均具有不稳定性.两种田鼠存活值的变化是由特定年份是否发生波动以及波动峰值出现的时间决定.增加初始阶段的种群密度及时间长度是造成两种动物种群波动峰值不同的主要原因.橙腹田鼠种群停止增长的原因是存活值降低,而草原田鼠则是繁殖活动减少.据推测,与种群波动初始密度相关的种群死亡率的差异是由捕食者的净效应(Net effect)决定的,调控两种群密度的因素均为非密度的其它生态学因子.由于特定年份田鼠种群捕食压力的不确定性,导致了橙腹田鼠和草原田鼠种群波动的不稳定性.%In this paper I summarize the results and conclusions of a 25-year study of demography of the prairie vole(Microtus ochrogaster), and meadow vole (M. pennsylvanicus).The roles of survival and reproduction are evaluated in respect to why population fluctuations occur some years and not others, what initiates a population fluctuation, and what is responsible for the variation in the peak density among population fluctuations. Population fluctuations of both species were erratic in respect to annual occurrence, the time of the peak density of fluctuations within years, and the hight of peak the density a given year. For both species, changes in survival appeared to be responsible for whether a fluctuation occurred a given year and the time of the peak density of a fluctuation. Population density at the beginning of the increase phase and length of the increase were most responsible for variation in peak

  13. Sheep grazing causes shift in sex ratio and cohort structure of Brandt's vole: Implication of their adaptation to food shortage. (United States)

    Li, Guoliang; Hou, Xianglei; Wan, Xinrong; Zhang, Zhibin


    Livestock grazing has been demonstrated to affect the population abundance of small rodents in grasslands, but the causative mechanism of grazing on demographic parameters, particularly the age structure and sex ratio, is rarely investigated. In this study, we examined the effects of sheep grazing on the cohort structure and sex ratio of Brandt's vole (Lasiopodomys brandtii) in Inner Mongolia of China by using large manipulative experimental enclosures during 2010-2013. Our results indicated that sheep grazing significantly decreased the proportion of the spring-born cohort, but increased the proportion of the summer-born cohort. Grazing increased the proportion of males in both spring and summer cohorts. In addition, we found a negative relation between population density and the proportion of the overwinter cohort. Our results suggest that a shift in the cohort structure and the sex ratio may be an important strategy for small rodents to adapt to changes in food resources resulting from livestock grazing.

  14. MKT500 week 10 Assignment 4 Part d Your Marketing Plan latest 2015   Vole Auto Inc




    MKT500 week 10 Assignment 4 Part d Your Marketing Plan latest 2015   Vole Auto Inc                 Click Link Below To Buy:                  Or Visit   Assignment 4: Part D: Your Marketing Plan – Video Presentation( previous assignment attached which you have to refernce to).   Due Week 10 and worth 200 points   Imagine that you are pitching your hypothetical service-based company’s mark...

  15. Contemporary radiation doses to mice and voles inhabiting East-Ural Radioactive Trace

    Energy Technology Data Exchange (ETDEWEB)

    Malinovsky, Georgy P.; Yarmoshenko, Ilia V. [Institute of Industrial Ecology UB RAS, 620219, 20, Sophy Kovalevskoy St., Ekaterinburg (Russian Federation); Starichenko, Vera I.; Chibiryak, Mikhail V. [Institute of Plant and Animal Ecology UB RAS, 620144, 202, 8 Marta St., Ekaterinburg (Russian Federation)


    East-Ural Radioactive Trace (EURT) is the radioactively contaminated territory formed after accidental explosion at nuclear waste storage facility of Mayak nuclear plant in 1957. Contemporary doses were estimated for the mice and voles, that were trapped by staff of IPAE at two sites in 2000-s. The site 1 is situated directly close to the territory of the plant. Contemporary surface {sup 90}Sr contamination is 24-40 MBq/m{sup 2}. The site 2 is located as far as 6 km to the north-east from the site 1 (3.1-8.1 MBq/m{sup 2}). Fifty years after accident long-lived {sup 90}Sr is most significant contributor to terrestrial animal's exposure. Skeletal activity concentration of {sup 90}Sr was measured utilising developed nondestructive method of bone beta-radiometry. To estimate radiation doses the strontium biokinetic model and dosimetric model for mouse-like rodent were designed. Skeletal activity concentration of {sup 90}Sr for animals trapped at site 1: 44-1249 Bq/g, mean 592 Bq/g; at site 2: 4-124 Bq/g, mean 32 Bq/g. Following parameters were selected as indicators of exposure: whole body dose (WBD) accumulated during 45 days, skeletal dose accumulated during 45 days and WBD rate on the last day before trapping. As can be seen in the table, there is a full agreement of the radiation dose and the level of surface contamination. For the animals inhabiting the most contaminated site mean WBD rate is close to 1 mGy/day. It can be reliably concluded that considering both internal and external exposures the dose rate exceeds 1 mGr/day in average. Publication 108 ICRP suggests derived consideration reference level (DCRL) for small mammals in a range 0.1-1 mGy/day. Thus in the most contaminated part of the EURT WBD rate exceeds the upper limit of the DCRL. Radiation doses on the second site are significantly lower. Mean WBD rate is below 0.1 mGy/day. At the same time, the WBD rate exceeds 0.1 mGy/day (lower limit of the DCRL) for approximately 40 % of animals from the

  16. Le recrutement et la fidélisation des bénévoles retraités par les associations


    Gourmelen, Andrea; Guillemot, Samuel; Privat, Hélène; Urien, Bertrand; Le Gall-Ely, Marine


    National audience; En raison du temps libre engendré par l’arrêt de l’activité professionnelle, les retraités deviennent une cible très convoitée par les associations à la recherche de bénévoles. Cependant, ils sont souvent considérés comme un segment homogène, d’où des difficultés de recrutement et de fidélisation par les associations. Pour y remédier, cet article propose une typologie de bénévoles retraités sur la base de leurs motivations et de caractéristiques psychosociales liées au viei...

  17. Mating behavior induces changes of expression of Fos protein, plasma testosterone and androgen receptors in the accessory olfactory bulb (AOB) of the male mandarin vole Microtus mandarinus


    Fengqin HE, Fadao TAI


    In order to investigate the neuroendocrine mechanism of the mating behavior in the adult male mandarin voles Microtus mandarinus, the radioimmunoassay (RIA) and immunohistochemistry methods were used to investigate the differences in plasma testosterone (T) concentrations and distribution of T immunoreactive neurons (T-IRs), androgen receptor immunoreactive neurons (AR-IRs) and Fos protein immunoreactive neurons (Fos-IRs) in the accessory olfactory bulb (AOB) and the main olfactory bulb (MOB)...

  18. Is It All in the Family? The Effects of Early Social Structure on Neural-Behavioral Systems of Prairie Voles (Microtus ochrogaster)


    Greenberg, GD; Van Westerhuyzen, JA; Bales, KL; Trainor, BC


    The transition to parenthood is generally associated with a reduction in anxiety or anxiety-like behavior across a wide range of species. In some species, juveniles provide supplementary parental care for younger siblings, a behavior known as alloparenting. Although the fitness consequences of alloparenting behavior have been a focus of evolutionary research, less is known about how alloparenting behavior impacts affective states. In the socially monogamous prairie vole (Microtus ochrogaster)...

  19. Mycobacterium microti tuberculosis in its maintenance host, the field vole (Microtus agrestis): characterization of the disease and possible routes of transmission. (United States)

    Kipar, A; Burthe, S J; Hetzel, U; Rokia, M Abo; Telfer, S; Lambin, X; Birtles, R J; Begon, M; Bennett, M


    The field vole (Microtus agrestis) is a known maintenance host of Mycobacterium microti. Previous studies have shown that infected animals develop tuberculosis. However, the disease is also known in cats and is sporadically reported from humans and other mammalian species. We examined trapped field voles from an endemic area, using a range of diagnostic approaches. These confirmed that a combination of gross and histological examination with culture is most appropriate to identify the true prevalence of the disease, which was shown to be more than 13% at times when older animals that have previously been shown to be more likely to develop the disease dominate the population. The thorough pathological examination of diseased animals showed that voles generally develop systemic disease with most frequent involvement of spleen and liver, followed by skin, lymph nodes, and lungs. The morphology of the lesions was consistent with active disease, and their distribution suggested skin wounds or oral and/or aerogenic infection as the main portal of entry. The demonstration of mycobacteria in open skin lesions, airways, and salivary glands indicated bacterial shedding from the skin and with sputum and saliva. This suggests not only the environment but also direct contact and devouring as likely sources of infection.

  20. Induced Pluripotent Stem Cells of Microtus levis x Microtus arvalis Vole Hybrids: Conditions Necessary for Their Generation and Self-Renewal (United States)

    Grigor’eva, E. V.; Shevchenko, A. I.; Medvedev, S. P.; Mazurok, N. A.; Zhelezova, A. I.; Zakian, S. M.


    Every year, the list of mammalian species for which cultures of pluripotent stem cells (PSCs) are generated increases. PSCs are a unique tool for extending the limits of experimental studies and modeling different biological processes. In this work, induced pluripotent stem cells (iPSCs) from the hybrids of common voles Microtus levis and Microtus arvalis, which are used as model objects to study genome organization on the molecular-genetic level and the mechanisms of X-chromosome inactivation, have been generated. Vole iPSCs were isolated and cultured in a medium containing cytokine LIF, basic fibroblast growth factor (bFGF), ascorbic acid, and fetal bovine serum. Undifferentiated state of vole iPSCs is maintained by activation of their endogenous pluripotency genes – Nanog, Oct4, Sox2, Sall4, and Esrrb. The cells were able to maintain undifferentiated state for at least 28 passages without change in their morphology and give rise to three germ layers (ectoderm, mesoderm and endoderm) upon differentiation. PMID:26798492

  1. The protective effects of social bonding on behavioral and pituitary-adrenal axis reactivity to chronic mild stress in prairie voles. (United States)

    McNeal, Neal; Appleton, Katherine M; Johnson, Alan Kim; Scotti, Melissa-Ann L; Wardwell, Joshua; Murphy, Rachel; Bishop, Christina; Knecht, Alison; Grippo, Angela J


    Positive social interactions may protect against stress. This study investigated the beneficial effects of pairing with a social partner on behaviors and neuroendocrine function in response to chronic mild stress (CMS) in 13 prairie vole pairs. Following 5 days of social bonding, male and female prairie voles were exposed to 10 days of CMS (mild, unpredictable stressors of varying durations, for instance, strobe light, white noise, and damp bedding), housed with either the social partner (paired group) or individually (isolated group). Active and passive behavioral responses to the forced swim test (FST) and tail-suspension test (TST), and plasma concentrations of adrenocorticotropic hormone (ACTH) and corticosterone, were measured in all prairie voles following the CMS period. Both female and male prairie voles housed with a social partner displayed lower durations of passive behavioral responses (immobility, a maladaptive behavioral response) in the FST (mean ± SEM; females: 17.3 ± 5.4 s; males: 9.3 ± 4.6 s) and TST (females: 56.8 ± 16.4 s; males: 40.2 ± 11.3 s), versus both sexes housed individually (females, FST: 98.6 ± 12.9 s; females, TST: 155.1 ± 19.3 s; males, FST: 92.4 ± 14.1 s; males, TST: 158.9 ± 22.0 s). Female (but not male) prairie voles displayed attenuated plasma stress hormones when housed with a male partner (ACTH: 945 ± 24.7 pg/ml; corticosterone: 624 ± 139.5 ng/ml), versus females housed individually (ACTH: 1100 ± 23.2 pg/ml; corticosterone: 1064 ± 121.7 ng/ml). These results may inform understanding of the benefits of social interactions on stress resilience. Lay Summary: Social stress can lead to depression. The study of social bonding and stress using an animal model will inform understanding of the protective effects of social bonds. This study showed that social bonding in a rodent model can protect against behavioral responses to stress, and may

  2. Plant phenolics as chemical defenses: Effects of natural phenolics on survival and growth of prairie voles (Microtus ochrogaster). (United States)

    Lindroth, R L; Batzli, G O


    Very few studies have shown experimentally that plant chemical defenses actually reduce the performance of individual mammalian herbivores, much less the density of mammalian populations. We investigated the effects of representatives of three classes of plant phenoiics on the survival and growth of prairie voles by incorporating the compounds into artificial diets and feeding them to weanlings for three weeks. At low levels of protein, both quercetin (a flavonoid) and tannic acid (a hydrolyzable tannin) caused reduced growth rates; no effect occurred at high levels of protein. Quebracho (a condensed tannin) inhibited feeding and thus was lethal at all levels of protein. These results indicate that plant phenolics are likely to influence the performance and dynamics of natural populations of microtine rodents by reducing the quality of available forage. The hypothesis that the primary mode of action of the phenoiics is the reduction of digestibility of protein was not supported. The reduced growth caused by both quercetin and tannic acid could be attributed primarily to their toxicity. The effect of quebracho resulted from reduced intake (unpalatability).

  3. A new permanent cell line derived from the bank vole (Myodes glareolus as cell culture model for zoonotic viruses

    Directory of Open Access Journals (Sweden)

    Herzog Sibylle


    Full Text Available Abstract Background Approximately 60% of emerging viruses are of zoonotic origin, with three-fourths derived from wild animals. Many of these zoonotic diseases are transmitted by rodents with important information about their reservoir dynamics and pathogenesis missing. One main reason for the gap in our knowledge is the lack of adequate cell culture systems as models for the investigation of rodent-borne (robo viruses in vitro. Therefore we established and characterized a new cell line, BVK168, using the kidney of a bank vole, Myodes glareolus, the most abundant member of the Arvicolinae trapped in Germany. Results BVK168 proved to be of epithelial morphology expressing tight junctions as well as adherence junction proteins. The BVK168 cells were analyzed for their infectability by several arbo- and robo-viruses: Vesicular stomatitis virus, vaccinia virus, cowpox virus, Sindbis virus, Pixuna virus, Usutu virus, Inkoo virus, Puumalavirus, and Borna disease virus (BDV. The cell line was susceptible for all tested viruses, and most interestingly also for the difficult to propagate BDV. Conclusion In conclusion, the newly established cell line from wildlife rodents seems to be an excellent tool for the isolation and characterization of new rodent-associated viruses and may be used as in vitro-model to study properties and pathogenesis of these agents.

  4. Negative relationships between cellular immune response, Mhc class II heterozygosity and secondary sexual trait in the montane water vole. (United States)

    Charbonnel, Nathalie; Bryja, Josef; Galan, Maxime; Deter, Julie; Tollenaere, Charlotte; Chaval, Yannick; Morand, Serge; Cosson, Jean-François


    Heterogeneities in immune responsiveness may affect key epidemiological parameters and the dynamics of pathogens. The roles of immunogenetics in these variations remain poorly explored. We analysed the influence of Major histocompatibility complex (Mhc) genes and epigamic traits on the response to phytohaemagglutinin in males from cyclic populations of the montane water vole (Arvicola scherman). Besides, we tested the relevance of lateral scent glands as honest signals of male quality. Our results did not corroborate neither the hypotheses of genome-wide heterozygosity-fitness correlation nor the Mhc heterozygote advantage. We found a negative relationship between Mhc hetetozygosity and response to phytohaemagglutinin, mediated by a specific Mhc homozygous genotype. Our results therefore support the hypothesis of the Arte-Dqa-05 homozygous genotype being a 'good' Mhc variant in terms of immunogenetic quality. The development of the scent glands seems to be an honest signal for mate choice as it is negatively correlated with helminth load. The 'good gene' hypothesis was not validated as Arte-Dqa-05 homozygous males did not exhibit larger glands. Besides, the negative relationship observed between the size of these glands and the response to phytohaemagglutinin, mainly for Mhc homozygotes, corroborates the immunocompetence handicap hypothesis. The Mhc variants associated with larger glands remain yet to be determined.

  5. Long-term spatiotemporal stability and dynamic changes in helminth infracommunities of bank voles (Myodes glareolus) in NE Poland. (United States)

    Grzybek, Maciej; Bajer, Anna; Bednarska, Małgorzata; Al-Sarraf, Mohammed; Behnke-Borowczyk, Jolanta; Harris, Philip D; Price, Stephen J; Brown, Gabrielle S; Osborne, Sarah-Jane; Siński, Edward; Behnke, Jerzy M


    Parasites are considered to be an important selective force in host evolution but ecological studies of host-parasite systems are usually short-term providing only snap-shots of what may be dynamic systems. We have conducted four surveys of helminths of bank voles at three ecologically similar woodland sites in NE Poland, spaced over a period of 11 years, to assess the relative importance of temporal and spatial effects on helminth infracommunities. Some measures of infracommunity structure maintained relative stability: the rank order of prevalence and abundance of Heligmosomum mixtum, Heligmosomoides glareoli and Mastophorus muris changed little between the four surveys. Other measures changed markedly: dynamic changes were evident in Syphacia petrusewiczi which declined to local extinction, while the capillariid Aonchotheca annulosa first appeared in 2002 and then increased in prevalence and abundance over the remaining three surveys. Some species are therefore dynamic and both introductions and extinctions can be expected in ecological time. At higher taxonomic levels and for derived measures, year and host-age effects and their interactions with site are important. Our surveys emphasize that the site of capture is the major determinant of the species contributing to helminth community structure, providing some predictability in these systems.

  6. Accumulation of point mutations and reassortment of genomic RNA segments are involved in the microevolution of Puumala hantavirus in a bank vole (Myodes glareolus) population. (United States)

    Razzauti, Maria; Plyusnina, Angelina; Henttonen, Heikki; Plyusnin, Alexander


    The genetic diversity of Puumala hantavirus (PUUV) was studied in a local population of its natural host, the bank vole (Myodes glareolus). The trapping area (2.5 x 2.5 km) at Konnevesi, Central Finland, included 14 trapping sites, at least 500 m apart; altogether, 147 voles were captured during May and October 2005. Partial sequences of the S, M and L viral genome segments were recovered from 40 animals. Seven, 12 and 17 variants were detected for the S, M and L sequences, respectively; these represent new wild-type PUUV strains that belong to the Finnish genetic lineage. The genetic diversity of PUUV strains from Konnevesi was 0.2-4.9 % for the S segment, 0.2-4.8 % for the M segment and 0.2-9.7 % for the L segment. Most nucleotide substitutions were synonymous and most deduced amino acid substitutions were conservative, probably due to strong stabilizing selection operating at the protein level. Based on both sequence markers and phylogenetic clustering, the S, M and L sequences could be assigned to two groups, 'A' and 'B'. Notably, not all bank voles carried S, M and L sequences belonging to the same group, i.e. S(A)M(A)L(A) or S(B)M(B)L(B). A substantial proportion (8/40, 20 %) of the newly characterized PUUV strains possessed reassortant genomes such as S(B)M(A)L(A), S(A)M(B)L(B) or S(B)M(A)L(B). These results suggest that at least some of the PUUV reassortants are viable and can survive in the presence of their parental strains.

  7. Inbreeding avoidance drives consistent variation of fine-scale genetic structure caused by dispersal in the seasonal mating system of Brandt's voles.

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    Xiao Hui Liu

    Full Text Available Inbreeding depression is a major evolutionary and ecological force influencing population dynamics and the evolution of inbreeding-avoidance traits such as mating systems and dispersal. Mating systems and dispersal are fundamental determinants of population genetic structure. Resolving the relationships among genetic structure, seasonal breeding-related mating systems and dispersal will facilitate our understanding of the evolution of inbreeding avoidance. The goals of this study were as follows: (i to determine whether females actively avoided mating with relatives in a group-living rodent species, Brandt's voles (Lasiopodomys brandtii, by combined analysis of their mating system, dispersal and genetic structure; and (ii to analyze the relationships among the variation in fine-genetic structure, inbreeding avoidance, season-dependent mating strategies and individual dispersal. Using both individual- and population-level analyses, we found that the majority of Brandt's vole groups consisted of close relatives. However, both group-specific FISs, an inbreeding coefficient that expresses the expected percentage rate of homozygosity arising from a given breeding system, and relatedness of mates showed no sign of inbreeding. Using group pedigrees and paternity analysis, we show that the mating system of Brandt's voles consists of a type of polygyny for males and extra-group polyandry for females, which may decrease inbreeding by increasing the frequency of mating among distantly-related individuals. The consistent variation in within-group relatedness, among-group relatedness and fine-scale genetic structures was mostly due to dispersal, which primarily occurred during the breeding season. Biologically relevant variation in the fine-scale genetic structure suggests that dispersal during the mating season may be a strategy to avoid inbreeding and drive the polygynous and extra-group polyandrous mating system of this species.

  8. Medium-term temporal stability of the helminth component community structure in bank voles (Clethrionomys glareolus) from the Mazury Lake District region of Poland. (United States)

    Bajer, A; Behnke, J M; Pawełczyk, A; Kuliś, K; Sereda, M J; Siński, E


    The structure of helminth communities in wild rodents is subject to seasonal variation, and is dependent on host age within years. Although between-year variation has been monitored, seldom has it been assessed rigorously by appropriate multifactorial analysis with potentially confounding factors taken into account. In this study we tested the null hypothesis that despite seasonal, host age and sex effects, helminth communities should show relative stability between years. Over a period of 3 years (1998-2000) we sampled bank vole (Clethrionomys glareolus) populations (total n = 250) at 2 points in the year: in spring, at the start of the breeding season, and in autumn, after the cessation of breeding. In spite of seasonal differences and strong age effects, the between-year effects were surprisingly small. Measures of component community structure (Berger-Parker dominance index, the dominant species, S. petrusewiczi) did not vary, or varied only slightly from year to year. The majority of measures of infracommunity structure [Brillouin's index of diversity, prevalence of all helminths combined, prevalence and abundance of H. mixtum (the most prevalent helminth), mean species richness] did not differ significantly between years when other factors such as age, sex and seasonal variation had been taken into account. Some between-year variations were found (at the component community level, Simpson's index of diversity; at the infracommunity level, prevalence and abundance of S. petrusewiczi and abundance of all helminths combined), but even these were modest in comparison to seasonal and age differences, and were primarily attributable to S. petrusewiczi. We conclude that despite dynamic within-year fluctuations, helminth communities in bank voles in this region of Poland show relative stability across years. The sporadic occurrence of individual platyhelminths at low prevalence, makes little difference to the overall structure, which is largely maintained by the key

  9. Red-backed vole brain promotes highly efficient in vitro amplification of abnormal prion protein from macaque and human brains infected with variant Creutzfeldt-Jakob disease agent. (United States)

    Nemecek, Julie; Nag, Nabanita; Carlson, Christina M.; Schneider, Jay R.; Heisey, Dennis M.; Johnson, Christopher J.; Asher, David M.; Gregori, Luisa


    Rapid antemortem tests to detect individuals with transmissible spongiform encephalopathies (TSE) would contribute to public health. We investigated a technique known as protein misfolding cyclic amplification (PMCA) to amplify abnormal prion protein (PrPTSE) from highly diluted variant Creutzfeldt-Jakob disease (vCJD)-infected human and macaque brain homogenates, seeking to improve the rapid detection of PrPTSE in tissues and blood. Macaque vCJD PrPTSE did not amplify using normal macaque brain homogenate as substrate (intraspecies PMCA). Next, we tested interspecies PMCA with normal brain homogenate of the southern red-backed vole (RBV), a close relative of the bank vole, seeded with macaque vCJD PrPTSE. The RBV has a natural polymorphism at residue 170 of the PrP-encoding gene (N/N, S/S, and S/N). We investigated the effect of this polymorphism on amplification of human and macaque vCJD PrPTSE. Meadow vole brain (170N/N PrP genotype) was also included in the panel of substrates tested. Both humans and macaques have the same 170S/S PrP genotype. Macaque PrPTSE was best amplified with RBV 170S/S brain, although 170N/N and 170S/N were also competent substrates, while meadow vole brain was a poor substrate. In contrast, human PrPTSE demonstrated a striking narrow selectivity for PMCA substrate and was successfully amplified only with RBV 170S/S brain. These observations suggest that macaque PrPTSE was more permissive than human PrPTSE in selecting the competent RBV substrate. RBV 170S/S brain was used to assess the sensitivity of PMCA with PrPTSE from brains of humans and macaques with vCJD. PrPTSE signals were reproducibly detected by Western blot in dilutions through 10-12 of vCJD-infected 10% brain homogenates. This is the first report showing PrPTSE from vCJD-infected human and macaque brains efficiently amplified with RBV brain as the substrate. Based on our estimates, PMCA showed a sensitivity that might be sufficient to detect PrPTSE in v

  10. Red-backed vole brain promotes highly efficient in vitro amplification of abnormal prion protein from macaque and human brains infected with variant Creutzfeldt-Jakob disease agent.

    Directory of Open Access Journals (Sweden)

    Julie Nemecek

    Full Text Available Rapid antemortem tests to detect individuals with transmissible spongiform encephalopathies (TSE would contribute to public health. We investigated a technique known as protein misfolding cyclic amplification (PMCA to amplify abnormal prion protein (PrP(TSE from highly diluted variant Creutzfeldt-Jakob disease (vCJD-infected human and macaque brain homogenates, seeking to improve the rapid detection of PrP(TSE in tissues and blood. Macaque vCJD PrP(TSE did not amplify using normal macaque brain homogenate as substrate (intraspecies PMCA. Next, we tested interspecies PMCA with normal brain homogenate of the southern red-backed vole (RBV, a close relative of the bank vole, seeded with macaque vCJD PrP(TSE. The RBV has a natural polymorphism at residue 170 of the PrP-encoding gene (N/N, S/S, and S/N. We investigated the effect of this polymorphism on amplification of human and macaque vCJD PrP(TSE. Meadow vole brain (170N/N PrP genotype was also included in the panel of substrates tested. Both humans and macaques have the same 170S/S PrP genotype. Macaque PrP(TSE was best amplified with RBV 170S/S brain, although 170N/N and 170S/N were also competent substrates, while meadow vole brain was a poor substrate. In contrast, human PrP(TSE demonstrated a striking narrow selectivity for PMCA substrate and was successfully amplified only with RBV 170S/S brain. These observations suggest that macaque PrP(TSE was more permissive than human PrP(TSE in selecting the competent RBV substrate. RBV 170S/S brain was used to assess the sensitivity of PMCA with PrP(TSE from brains of humans and macaques with vCJD. PrP(TSE signals were reproducibly detected by Western blot in dilutions through 10⁻¹² of vCJD-infected 10% brain homogenates. This is the first report showing PrP(TSE from vCJD-infected human and macaque brains efficiently amplified with RBV brain as the substrate. Based on our estimates, PMCA showed a sensitivity that might be sufficient to detect Pr

  11. Do females influence paternal responsiveness in male prairie voles Microtus ochrogaster by increasing the salience of infant odors?

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    Damaris-Lois LANG YAMOAH,Wilhemina LARYEA, Fiker FASSIL, Maryam BAMSHAD


    Full Text Available Male prairie voles become more responsive to infants following cohabitation with a female. Exposure to female sensory cues prior to offspring birth may influence male paternal tendencies by modifying his response to infant odors in particular or to odors in general. To test these hypotheses, males were housed with an unfamiliar female or a same-sex sibling for 13 days then examined for their response towards either live infants or infant-like inanimate objects covered with one of three odors: water, infant, sub-adult. We recorded the number of males that retrieved and manipulated the infants or odor-covered objects and measured the frequency and duration of time males spent attending to them or engaged in other non-social activities. Female-Cohabited males approached the container holding infant-odor covered objects faster than Male-Cohabited males, but showed no differences in time spent manipulating those objects. Males in both groups spent more time manipulating live infants than odor-covered objects. However, Female-Cohabited subjects were more likely to manipulate odor-covered objects as well as live infants than Male-Cohabited subjects. Additionally, the frequency of self-grooming in Female-Cohabited males was higher for water-covered objects compared to Male-Cohabited males. In presence of water and live infants, Female-Cohabited males groomed themselves with greater frequency than in presence of infant odor or sub-adult odor. The data suggest that female cues increase the male’s sensitivity to infant odors and enhance the salience of non-social odors [Current Zoology 58 (3: 317–325, 2013].

  12. Early rearing experience is related to altered aggression and vasopressin production following chronic social isolation in the prairie vole. (United States)

    Perkeybile, Allison M; Bales, Karen L


    Parent-offspring interactions early in life can permanently shape the developmental path of those offspring. Manipulation of maternal care has long been used to alter the early-life environment of infants and impacts their later social behavior, aggression, and physiology. More recently, naturally occurring variation in maternal licking and grooming behavior has been shown to result in differences in social behavior and stress physiology in adult offspring. We have developed a model of natural variation in biparental care in the prairie vole (Microtus ochrogaster) and have demonstrated an association between the amount of early care received and later social behavior. In this study, we investigate the relationship between early life care and later aggression and neuroendocrine responses following chronic social isolation. Male and female offspring were reared by their high-contact (HC) or low-contact (LC) parents, then housed for 4 weeks post-weaning in social isolation. After 4 weeks, half of these offspring underwent an intrasexual aggression test. Brains and plasma were collected to measure corticotropin-releasing hormone (CRH) and vasopressin (AVP) immunoreactivity and plasma corticosterone (CORT). Male offspring of LC parents engaged in more aggressive behavior in the intrasexual aggression test compared to HC males. Female offspring of HC parents had higher plasma CORT levels after chronic social isolation and increases in the number and density of AVP-immunopositive cells in the supraoptic nucleus following an intrasexual aggression test. These findings show that the impact of early life biparental care on behavior and HPA activity following a social stressor is both sex-dependent and early experience-specific.

  13. Testicular steroid metabolism in juvenile bank voles (Clethrionomys glareolus Schreber) exposed to different photoperiods: an in vitro study. (United States)

    Tänkä, K M; Teräväinen, T; Wallgren, H


    Juvenile male bank voles (18-22 days of age) were either sacrificed immediately (Group C) or subjected first to a long (18L:6D, lights on 0600-2400; Group L) or a short (6L:18D, lights on 0800-1400; Group S) photoperiod for 1 week. The animal were killed by decapitation, the gonads were excised, and minced, and the conversion of [4-14C]pregnenolone (delta 3P) and [4-14C]dehydroepiandrosterone (DHA) to metabolites was studied in vitro. The radioactive steroids formed were separated and identified by thin-layer chromatography (TLC). The conversion of delta 3P to C19-steroids increased markedly from 35 (Group C) to 86% (Group L) during the first week in the long photoperiod whereas in the short photoperiod a decrease to 14.42% (Group S) was observed. The reduced production of C19-steroids in the more inactive testes was accompanied by the accumulation of progesterone (delta 4P) (52.98% Group S and 24.9% Group C) and small amounts of 17 alpha-hydroxyprogesterone (17 alpha-OH-delta 4P) (2.5 and 4.5%, respectively), whereas in Group L only trace amounts of these metabolites were encountered. No marked differences in the metabolism of [4-14C]DHA between the photoperiodic groups were observed. These results seem to indicate that at least in vitro marked changes in C17-C20-lyase and/or 17 alpha-hydroxylase activities occur in this seasonally breeding species during testicular maturation and photoperiodically induced regression.

  14. Do females influence paternal responsiveness in male prairie voles Microtus ochrogaster by increasing the salience of infant odors?

    Institute of Scientific and Technical Information of China (English)

    Damaris-Lois LANG YAMOAH; Wilhemina LARYEA; Fiker FASSIL; Maryam BAMSHAD


    Male prairie voles become more responsive to infants following cohabitation with a female.Exposure to female sensory cues prior to offspring birth may influence male paternal tendencies by modifying his response to infant odors in particular or to odors in general.To test these hypotheses,males were housed with an unfamiliar female or a same-sex sibling for 13 days then examined for their response towards either live infants or infant-like inanimate objects covered with one of three odors:water,infant,sub-adult.We recorded the number of males that retrieved and manipulated the infants or odor-covered objects and measured the frequency and duration of time males spent attending to them or engaged in other non-social activities.Female-Cohabited males approached the container holding infant-odor covered objects faster than Male-Cohabited males,but showed no differences in time spent manipulating those objects.Males in both groups spent more time manipulating live infants than odor-covered objects.However,Female-Cohabited subjects were more likely to manipulate odor-covered objects as well as live infants than Male-Cohabited subjects.Additionally,the frequency of self-grooming in Female-Cohabited males was higher for water-covered objects compared to Male-Cohabited males.In presence of water and live infants,Female-Cohabited males groomed themselves with greater frequency than in presence of infant odor or sub-adult odor.The data suggest that female cues increase the male's sensitivity to infant odors and enhance the salience of non-social odors.

  15. Prisoners in their habitat? Generalist dispersal by habitat specialists: a case study in southern water vole (Arvicola sapidus.

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    Alejandro Centeno-Cuadros

    Full Text Available Habitat specialists inhabiting scarce and scattered habitat patches pose interesting questions related to dispersal such as how specialized terrestrial mammals do to colonize distant patches crossing hostile matrices. We assess dispersal patterns of the southern water vole (Arvicola sapidus, a habitat specialist whose habitat patches are distributed through less than 2% of the study area (overall 600 km² and whose populations form a dynamic metapopulational network. We predict that individuals will require a high ability to move through the inhospitable matrix in order to avoid genetic and demographic isolations. Genotypes (N = 142 for 10 microsatellites and sequences of the whole mitochondrial Control Region (N = 47 from seven localities revealed a weak but significant genetic structure partially explained by geographic distance. None of the landscape models had a significant effect on genetic structure over that of the Euclidean distance alone and no evidence for efficient barriers to dispersal was found. Contemporary gene flow was not severely limited for A. sapidus as shown by high migration rates estimates (>10% between non-neighbouring areas. Sex-biased dispersal tests did not support differences in dispersal rates, as shown by similar average axial parent-offspring distances, in close agreement with capture-mark-recapture estimates. As predicted, our results do not support any preferences of the species for specific landscape attributes on their dispersal pathways. Here, we combine field and molecular data to illustrate how a habitat specialist mammal might disperse like a habitat generalist, acquiring specific long-distance dispersal strategies as an adaptation to patchy, naturally fragmented, heterogeneous and unstable habitats.

  16. A Note on the Distribution and Geographical Variation of the Gray-sided Vole ( Clethrionomys rufocanus Sund., 1846-1847 in Mongolia

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    Davaa Lkhagvasuren


    Full Text Available In this paper, we present a new distribution record for the Gray-sided vole found in an isolated birch forest in southern Mongolia, at Ih Bogd mountain. This represents a very remote and isolated population of this species from its main range of forested areas. Morphological characters were used to determine the morphological variation of Gray-sided vole in the investigated southern population in comparison with two other populations: one from Honin nuga (Hentii mountain range and the other from Hangai mountains. We revealed fi ve distinct morphotypes based on the fur coloration patterns. Two morphotypes were found in the isolated Ih Bogd population, while there were two morphotypes for the Hentii and one for the Hangai population. Moreover, based on the nine standard skull measurements, we found a marginally signi fi cant difference among the three populations, indicating that there are detectable differences. However, the discriminant function analysis was moderate in classifying the three populations. This small variation may be explained by our limited sample sizes (6-15 individuals per population and possibly by the fact that the southern population of this species may have been isolated only for a short time.

  17. Effects of paternal deprivation on cocaine-induced behavioral response and hypothalamic oxytocin immunoreactivity and serum oxytocin level in female mandarin voles. (United States)

    Wang, Jianli; Fang, Qianqian; Yang, Chenxi


    Early paternal behavior plays a critical role in behavioral development in monogamous species. The vast majority of laboratory studies investigating the influence of parental behavior on cocaine vulnerability focus on the effects of early maternal separation. However, comparable studies on whether early paternal deprivation influences cocaine-induced behavioral response are substantially lacking. Mandarin vole (Microtus mandarinus) is a monogamous rodent with high levels of paternal care. After mandarin vole pups were subjected to early paternal deprivation, acute cocaine- induced locomotion, anxiety- like behavior and social behavior were examined in 45day old female pups, while hypothalamic oxytocin immunoreactivity and serum oxytocin level were also assessed. We found that cocaine increased locomotion and decreased social investigation, contact behavior and serum oxytocin level regardless of paternal care. Cocaine increased anxiety levels and decreased oxytocin immunoreactive neurons of the paraventricular nuclei and supraoptic nuclei in the bi-parental care group, whilst there were no specific effects in the paternal deprivation group. These results indicate that paternal deprivation results in different behavioral response to acute cocaine exposure in adolescents, which may be in part associated with the alterations in oxytocin immunoreactivity and peripheral OT level. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. The long-term effect of cadmium exposure through food on the postnatal development of the bank vole (Clethrionomys glareolus Schreber, 1780). (United States)

    Białońska, Dobrosława; Zakrzewska, Marta; Sawicka-Kapusta, Katarzyna; Konior, Magdalena


    Cadmium is well known for its toxicity to the animal body. However, its effect on pregnancy and the development of young animals is still not well understood. This study examined such effects, using bank voles captured from the wild to make the results closer to those which could be expected in the natural environment. One group of animals was fed 7 microg g(-1) cadmium in the food, a second 35 microg g(-1), and a third no cadmium, as a control. The concentrations of cadmium in the whole bodies of young bank voles were determined on the 3rd, 5th, or 10th day of life. The cadmium level in the bodies of animals exposed to 35 microg g(-1) of cadmium was significantly higher than in those from either the control group or the group receiving 7 microg g(-1) of cadmium, which did not differ from each other. The cadmium level did not change with animal age in any of the study groups. Concentrations of Zn, Cu, and Fe were also determined in the whole body of young animals, as cadmium is known to disturb the metabolism of these essential metals through antagonistic activity. Both Cu and Fe levels were negatively correlated with cadmium concentrations, while a positive correlation was found between zinc and cadmium in the young animal bodies. Also found was higher offspring mortality in the group receiving 35 microg g(-1) of cadmium in food. There was no difference in young animal body weight between the study groups.

  19. Coat color and its effect on preference for the scent marks of opposite-sex conspecifics in the meadow vole Microtus pennsylvanicus

    Institute of Scientific and Technical Information of China (English)

    Ashlee A. VAUGHN; Antedra A. FINGER; Porshia E. GIBBS; Michael H. FERKIN


    Many mammal species can distinguish between opposite-sex conspecifics that differ in a certain trait.In that coat coloration is associated with differences in physiological and behavioral traits,coat color may affect the attractiveness of odor cues produced by conspecifics.Individuals may be able to respond preferentially to eonspecifics with a particular coat color.In the present study,we test the hypothesis that scent marks of brown and blond voles differ in their attractiveness to male and female conspecifics.Male voles and brown females did not discriminate between blond- and brown-coated opposite-sex conspecifics suggesting that they are neither selecting potential mates dissociatively nor associatively.However,blond females behaved as if the scent marks of blond males were more attractive than were the scent marks of brown males.Our data suggest that blond females who are already conspicuous to predators,may select blond males as mates because they do not appreciably increase the risk of detection to predators,particularly avian predators.Moreover,because these conspicuous males have survived to mate they may have good genes that reflect their relatively higher quality [Current Zoology 58 (2):221-227,2012].

  20. Effects of an MHC-DRB genotype and allele number on the load of gut parasites in the bank vole Myodes glareolus. (United States)

    Kloch, Agnieszka; Babik, Wiesław; Bajer, Anna; Siński, Edward; Radwan, Jacek


    The major histocompatibility complex (MHC) genes code for the proteins responsible for pathogen recognition. The MHC class II DRB gene is multiplicated in the bank vole, Myodes glareolus, with different numbers of loci found in different individuals. Possessing large numbers of loci should increase the probability of pathogen recognition, but according to the optimality hypothesis, there is a cost of possessing too many MHC alleles. Using 454 technology, we determined the individual DRB allelic diversity and related it to the load of intestinal parasites in voles collected from three sites separated by a distance of 12 to 27 km. The analysis of six microsatellite loci revealed significant population structure (F(ST) = 0.07). The sites differed significantly in the prevalence and abundance of nematode species as well. We found two significant associations between MHC alleles and the intensity of the infection with the most prevalent nematode, Aspiculuris tetraptera. One of these associations was population-specific. This result suggests that the directions of selection can differ between populations connected by a low level of gene flow, which may contribute to the maintenance of high DRB allele diversity. In accordance with the optimality hypothesis, individuals with an intermediate number of alleles carried the lowest number of nematode species and had the lowest prevalence of A. tetraptera. However, the intensity of infection with A. tetraptera was linearly and negatively associated with the number of alleles.

  1. De novo transcriptome assembly facilitates characterisation of fast-evolving gene families, MHC class I in the bank vole (Myodes glareolus). (United States)

    Migalska, M; Sebastian, A; Konczal, M; Kotlík, P; Radwan, J


    The major histocompatibility complex (MHC) plays a central role in the adaptive immune response and is the most polymorphic gene family in vertebrates. Although high-throughput sequencing has increasingly been used for genotyping families of co-amplifying MHC genes, its potential to facilitate early steps in the characterisation of MHC variation in nonmodel organism has not been fully explored. In this study we evaluated the usefulness of de novo transcriptome assembly in characterisation of MHC sequence diversity. We found that although de novo transcriptome assembly of MHC I genes does not reconstruct sequences of individual alleles, it does allow the identification of conserved regions for PCR primer design. Using the newly designed primers, we characterised MHC I sequences in the bank vole. Phylogenetic analysis of the partial MHC I coding sequence (2-4 exons) of the bank vole revealed a lack of orthology to MHC I of other Cricetidae, consistent with the high gene turnover of this region. The diversity of expressed alleles was characterised using ultra-deep sequencing of the third exon that codes for the peptide-binding region of the MHC molecule. High allelic diversity was demonstrated, with 72 alleles found in 29 individuals. Interindividual variation in the number of expressed loci was found, with the number of alleles per individual ranging from 5 to 14. Strong signatures of positive selection were found for 8 amino acid sites, most of which are inferred to bind antigens in human MHC, indicating conservation of structure despite rapid sequence evolution.

  2. Les enjeux de la fidélisation bénévole dans les grandes associations : la Croix-Rouge française


    Rachel Maalouly


    La fidélisation au sein des entreprises dites classiques est une question d'actualité très présente en ressources humaines. La fidélisation au sein des associations des bénévoles est un sujet d'actualité. La plupart des études traitent des moyens de fidéliser ces ressources, très peu considèrent les enjeux de la fidélisation au sein de ces entreprises de l'économie sociale. L'objet de notre travail est de mieux comprendre ces enjeux au sein des grandes associations telle que la Croix-Rouge fr...

  3. Multiple parasites mediate balancing selection at two MHC class II genes in the fossorial water vole: insights from multivariate analyses and population genetics. (United States)

    Tollenaere, C; Bryja, J; Galan, M; Cadet, P; Deter, J; Chaval, Y; Berthier, K; Ribas Salvador, A; Voutilainen, L; Laakkonen, J; Henttonen, H; Cosson, J-F; Charbonnel, N


    We investigated the factors mediating selection acting on two MHC class II genes (DQA and DRB) in water vole (Arvicola scherman) natural populations in the French Jura Mountains. Population genetics showed significant homogeneity in allelic frequencies at the DQA1 locus as opposed to neutral markers (nine microsatellites), indicating balancing selection acting on this gene. Moreover, almost exhaustive screening for parasites, including gastrointestinal helminths, brain coccidia and antibodies against viruses responsible for zoonoses, was carried out. We applied a co-inertia approach to the genetic and parasitological data sets to avoid statistical problems related to multiple testing. Two alleles, Arte-DRB-11 and Arte-DRB-15, displayed antagonistic associations with the nematode Trichuris arvicolae, revealing the potential parasite-mediated selection acting on DRB locus. Selection mechanisms acting on the two MHC class II genes thus appeared different. Moreover, overdominance as balancing selection mechanism was showed highly unlikely in this system.

  4. [A modular approach to studying of fluctuating asymmetry of complex morphological structures in rodents with the mandible of the bank vole (Clethrionomys glareolus, Arvicolinae, Rodentia) as an example]. (United States)

    Ialkovskaia, L É; Borodin, A V; Fominykh, M A


    The expediency of a modular approach to estimating fluctuating asymmetry (FA) of complex morphological structures was shown using the mandible of the bank vole (Clethrionomys glareolus Schreber, 1780) as an example. FA of the shape of two mandibular regions (modules) defined developmentally and functionally, was assessed by means of geometric morphometrics. The differences between mandibular regions in the FA levels were found for both individual landmarks and integral indices of asymmetry. Regardless of age, gender or sampling year, FA estimates obtained for posterior region including part of the ramus and processes were higher than those for anterior region including the diastemal area. The results suggest that modularity of complex morphological structures should be taken into account when analyzing FA.

  5. Sex differences, effects of male presence and coordination of nest visits in prairie voles (Microtus ochrogaster) during the immediate postnatal period (United States)

    Mcguire, B.; Parker, E.; Bemis, W.E.


    Little is known about sex differences in parental behavior of biparental mammals and if mates in such species coordinate care of young. We studied parental care displayed by prairie voles (Microtus ochrogaster) under seminatural laboratory conditions during the first 3 d of life of their offspring. Through direct observations and videotaping, we monitored members of male-female pairs to determine if sex differences in early parental behavior exist and if mothers and fathers coordinate visits to the nest. To assess the impact of fathers on survival of pups and behavior of mothers, we also examined parental care displayed by single females toward their young. Male and female members of breeding pairs differed dramatically in degree of parental care. Females spent more time in the nest with young and licked them more frequently than did males. Additionally, females maintained the nest more frequently than did males, whereas they maintained runways less frequently. Although coordination of visits to the nest was not perfect between members of pairs, pups of pairs were left alone for less time than were pups of single females. Parental behavior displayed by paired and single females did not differ, nor did survival of their young to day 3 or 15. We suggest that provision of ample space and cover to vole parents rearing young in captivity promotes expression of sex differences in parental behavior, but that even seminatural conditions are not sufficient to yield benefits of father presence to survival of young. Under more challenging conditions, such as cold temperatures or presence of predators, benefits of father presence might emerge.

  6. Maternal corticosterone but not testosterone level is associated with the ratio of second-to-fourth digit length (2D:4D) in field vole offspring (Microtus agrestis). (United States)

    Lilley, Thomas; Laaksonen, Toni; Huitu, Otso; Helle, Samuli


    The steroid environment encountered by a foetus can strongly affect its post-natal physiology and behaviour. It has been proposed that steroid concentrations experienced in utero could be estimated from adults by measuring their second-to-fourth digit length ratio (2D:4D). However, there is still little direct evidence that intra-uterine steroid levels affect individual 2D:4D. We examined whether maternal pre-pregnancy testosterone and corticosterone levels (as estimates of intra-uterine testosterone and corticosterone exposure) affected the 2D:4D of pups in non-domesticated field voles (Microtus agrestis), measured by X-rays at the age of weaning (21 days). Furthermore, for the first time in a non-human species, we studied whether testosterone and corticosterone levels correlated with 2D:4D in adult females. We found that the maternal pre-pregnancy level of testosterone was not associated with offspring 2D:4D in either the left or the right paw. Instead, maternal pre-pregnancy corticosterone level was positively correlated with offspring 2D:4D in the right paw, but unrelated to 2D:4D in the left paw. In addition, the 2D:4D of adult females was not associated with either their circulating testosterone or corticosterone levels. Our results suggest that in field voles maternally administered testosterone is not a major determinant of offspring 2D:4D, whereas maternal stress appears to account for some of the variation in the 2D:4D of their offspring.

  7. Mating behavior induces changes of expression of Fos protein, plasma testosterone and androgen receptors in the accessory olfactory bulb (AOB of the male mandarin vole Microtus mandarinus

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    Fengqin HE, Fadao TAI


    Full Text Available In order to investigate the neuroendocrine mechanism of the mating behavior in the adult male mandarin voles Microtus mandarinus, the radioimmunoassay (RIA and immunohistochemistry methods were used to investigate the differences in plasma testosterone (T concentrations and distribution of T immunoreactive neurons (T-IRs, androgen receptor immunoreactive neurons (AR-IRs and Fos protein immunoreactive neurons (Fos-IRs in the accessory olfactory bulb (AOB and the main olfactory bulb (MOB following exposure to clean hard-wood shavings (control group, soiled bedding (exposure group or contact with an estrous female (mating group. Results showed that plasma T concentration was significantly higher in the mating group than that in the exposure group, and both the mating group and the exposure group displayed significantly higher plasma T concentration than the control group. T-IRs, AR-IRs and Fos-IRs were investigated with the immunohistochemistry method in granule cell (GC and mitral cell (MC of the MOB and the AOB in the three groups. There were significantly more T-IRs, AR-IRs and Fos-IRs in MC and GC of the AOB in the mating group than that in the exposure group or the control group. T-IRs, AR-IRs and Fos-IRs did not show significant differences between the exposure group and the control group. Furthermore, obvious differences in MC and GC of the MOB were not found among the three groups. The results confirm that both changes of T and AR in the AOB might be underlying mating behavior in the adult male mandarin voles [Current Zoology 55 (4: 288–295, 2009].

  8. Factors affecting the component community structure of haemoparasites in bank voles (Clethrionomys glareolus) from the Mazury Lake District region of Poland. (United States)

    Bajer, A; Pawelczyk, A; Behnke, J M; Gilbert, F S; Sinski, E


    The prevalence and abundance of infections with haemoparasites were studied over a 3 year period in Clethrionomys glareolus (bank vole, n = 420) sampled from forests in the NE of Poland. Total species richness was 5 (Prevalence = Haemobartonella sp. 63.1%, Bartonella grahamii 27.4%, Hepatozoon erhardovae 31.4%, Trypanosoma evotomys 15% and Babesia microti 1.0%) with 81.9% of the voles carrying at least 1 species and a mean infracommunity species richness of 1.4. Variation in species richness was determined primarily by season and year, and the interaction of these factors. The observed frequency distribution of infracommunity species richness did not differ from that predicted by a null model, suggesting that there were no marked associations between the species. Analyses of prevalence and abundance of infection with each species in turn, revealed that overall the principal causes of variation were temporal and seasonal and their interaction, intrinsic factors such as age and sex playing only a minor role. However, the relative importance of specific extrinsic, and rarely intrinsic, factors varied and was distinct for each of the species in the study. Prevalence data revealed 4 sets of 2-way associations between species, mostly varyingly dependent on combinations of intrinsic and extrinsic factors. Analysis of quantitative associations suggested 4 sets of positive 2-way interactions, 3 of which remained after controlling for the effect of extrinsic and intrinsic factors on the abundance of each species, but only one could be unequivocally accepted (Haemobartonella sp. +B. grahamii) after correction for multiple comparisons. These data are discussed in the context of the changing ecological profiles in this region of Eastern Europe and, in a wider context, in relation to current understanding of the factors which shape component community structures of haemoparasites in wild rodents.

  9. [Biological effects in natural populations of small rodents in radiation-polluted territories. Dynamics of chromosome aberration frequency in a number of generations of European bank vole (Clethrionomys glareolus, Schreber)]. (United States)

    Goncharova, R I; Riabokon', N I


    The dynamics of chromosome aberration frequency in bone marrow cells of many generations (14) of bank vole living in the radioactive trace of the Chernobyl catastrophe (1986-1992) has been analysed. The study revealed that the chromosome aberration frequency in voles in the areas with radio-contamination density 220 and 1526 kBq/m2 (for 137Cs) significantly exceeds the control level 3-7 times over the whole period under investigation. The dynamics of the frequency of structural chromosome injuries from 1986 to 1991-1992 is characterised by the tendency to increase in all populations inhabiting the areas with various radio-contamination density (8-1526 kBq/m2).

  10. Assessment of metals exposure and sub-lethal effects in voles and small birds captured near the DeLong Mountain Regional Transportation System Road, Cape Krusenstern National Monument, Alaska, 2006 (United States)

    Brumbaugh, William G.; Mora, Miguel A.; May, Thomas W.


    Voles (n=6) and small ground-nesting birds (n=12) were live-captured near the DeLong Mountain Regional Transportation System haul road in Cape Krusenstern National Monument in northwest Alaska in 2006 to assess metals exposure and sub-lethal biological effects. Similar numbers of animals were captured from a reference site in southern Cape Krusenstern National Monument for comparison. Histopathological examination of selected organs, blood analysis, and analysis for aluminum, barium, cadmium, lead, and zinc concentrations in liver and blood samples were performed. Voles and small birds captured from near the haul road had about 20 times greater blood and liver lead concentrations and about 3 times greater cadmium concentrations when compared to those from the reference site. Barium and zinc tissue concentrations of animals collected from different sites were not remarkably different, and aluminum concentrations were below the reporting limits in most samples. There was no clear evidence of serious sub-lethal biological effects such as lesions in internal organs or DNA damage in blood in any of the animals. Accordingly, blood and liver lead concentrations in animals captured near the haul road generally were less than tissue concentration thresholds associated with serious biological effects reported from other studies; however, subtle effects resulting from lead exposure, such as the suppression of the activity of certain enzymes, cannot be ruled out for those animals nearest the haul road. Notably, liver lead concentrations of voles and small birds at the reference location were considerably less than those previously reported for similar animals at reference sites in other parts of the United States, Canada, and Europe. Results from this reconnaissance-level study indicate that voles and small birds inhabiting this area are not suffering serious biological effects as a result of metals exposure; however, continued monitoring of lead and other metals is

  11. A revision of the distribution of Cabrera’s vole (Microtus cabrerae Thomas 1906 in Andalusia (southern Spain

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    Jose Garrido-García


    Full Text Available Abstract This paper consists of a revision of existing records of Cabrera’s Vole Microtus cabrerae in Andalusia (south of Spain and provides new data from a survey of both previously investigated and new areas. Cabrera’s voles were found at only three of the 17 previously known localities, whilst the species may be in fact extinct in 12 localities. Our results suggest that the species could have disappeared from the central part of the province of Granada. Nevertheless, fieldwork revealed 138 new localities in 24 UTM 10x10 km squares scattered throughout the Cazorla-Segura Mountains and the extreme north of the provinces of Almería and Granada. In 13 of these squares, the presence of the species was confirmed by the capture of 16 specimens. Despite the new localities discovered, the species should still be considered as ‘Critically Endangered’ in Andalusia. Riassunto Revisione della distribuzione dell'arvicola di Cabrera (Microtus cabrerae Thomas 1906 in Andalusia (Spagna meridionale Il presente articolo consiste di una revisione dei dati disponibili sull'arvicola di Cabrera Microtus cabrerae in Andalusia (Spagna meridionale e fornisce dati originali ottenuti tramite un'indagine svolta sia in aree già investigate, sia in aree mai monitorate in precedenza. L'arvicola di Cabrera è stata individuata solo in 3 delle 17 località segnalate in letteratura, mentre in 12 di esse potrebbe essere estinta. I risultati ottenuti suggeriscono che la specie sia attualmente scomparsa dalla porzione centrale della provincia di Granada. Tuttavia, le indagini hanno permesso di rilevare la presenza della specie in 138 nuove località distribuite in 24 quadrati UTM 10x10 km corrispondenti alla cetena montuosa di Cazorla-Segura e all'estrema parte settentrionale delle province di Almeria e Granada. In 13 quadrati la presenza è stata confermata tramite la cattura di 16

  12. Criterion-referenced evaluation of day one clinical competencies of veterinary students: VOLES-the VMTH (Veterinary Medicine Teaching Hospital) Online Evaluation System. (United States)

    Zeck, Steven; Wall, Judy A; Smith, Bradford P; Wilson, W David; Walsh, Donal A


    This article describes an extensive online criterion-referenced evaluation system for the assessment of veterinary students' achievement during their final year's Doctor of Veterinary Medicine (or equivalent) clinical education. Data are reported for the 2001 to 2009 University of California at Davis veterinary graduates, for a total of more than 1,100 students. These criterion-referenced evaluations extensively document the level of clinical skills attained and demonstrated during the individual clinical rotations that comprise the fourth-year curriculum. On average, in each of the 17,500 clinical rotations undertaken during this time period, student performance was assessed in at least 11 separate areas of skills, knowledge, and professional attributes. This provided more than 200,000 criterion-referenced judgments of the individual clinical attributes of graduates over nine years. The system is based on a previously detailed and validated definition of the skills, knowledge, and professional attributes that students should have demonstrated before graduation. The extensive database that this system has provided has established that this system, termed VOLES (VMTH [Veterinary Medicine Teaching Hospital] On-Line Evaluation System), is an effective tool to assess the clinical capabilities of veterinary students and their achievement of the "Day One" skills required for entering clinical practice. These expected proficiencies are balanced according to the differing expectations that each area of veterinary clinical practice demands.

  13. 根田鼠母体摄食经历对幼体食物选择的影响%Effects of foraging experience of root vole maternity on food selection of offspring

    Institute of Scientific and Technical Information of China (English)

    李俊年; 杨冬梅; 陶双伦; 邓凯东


    Social learning is a phenotype of plastic behavior of animals, which enables the individuals to acquire adaptive behavior patterns suitable for local habitats. However, the transmission of food preference from vole maternity to its offspring has largely been ignored. Taking the root vole in Qinghai-Tibetan Plateau as test object, a laboratory experiment was conducted, with the foods treated with 0.01% glucide or 0.1% fruit juice supplied to the vole maternity during its late pregnancy period and lactation, and to the offspring after weaned, aimed to observe the food preferences of the offspring. The results demonstrated that the weaned voles preferred the food items that their mothers had during pregnancy and lactation. Root vole lived in the environment with dramatic seasonal variation, and, for the weaned voles, learning the food preferences of their mothere was a phenotype of plastic behavior, being advantageous to acquire the adaptive behavior patterns suitable for local habitats.%社会学习是动物的一种可塑性行为表型,能使动物个体获得提高其适合度的行为模式.母体对幼体的食性形成具有重要的影响.本文以栖息于青藏高原的根田鼠作为研究对象,在实验室条件下,根田鼠母体怀孕后期及哺乳期分别供给以0.01%糖精或0.1%橘子汁处理的食物,当幼体断乳时,同时供给断乳幼体糖精和橘子汁分别处理的食物,测定其食物选择.结果表明:根田鼠母体在怀孕期和哺乳期摄食经橘子汁处理的食物,断乳幼体在同时供给经橘子汁处理的食物和糖精处理的食物时,断乳幼体喜食经橘子汁处理的食物;而母体在怀孕期和哺乳期摄食经糖精处理的食物,断乳幼体在同时供给根田鼠断乳幼体经橘子汁处理和糖精处理的食物时,断乳幼体喜食经糖精处理的食物.说明根田鼠在断乳后仍喜食母体在怀孕期和哺乳期摄食过的食物种类.根田鼠栖息于季

  14. 雌、雄草原田鼠外周骨骼肌肌球蛋白重链的表达%Myosin heavy chain expression in peripheral muscles of male and female prairie voles Microtus ochrogaster

    Institute of Scientific and Technical Information of China (English)

    Andrew C. FRY; Michael H. FERKIN; Brian K. SCHILLING; Stuart T. LEONARD; Matthew P. HARBER; Martyn R. RUBIN; J.Chadwick SMITH


    已往的研究对于实验室应用的各种啮齿类动物,如大鼠和小鼠骨骼肌蛋白表达的特性已有报道.然而,至今不清楚其它啮齿类动物如野生鼠骨骼肌蛋白的表达或性双态性的特征,而这些野生鼠的行为学、形态学及生理学特点均已有报道.已知骨骼肌的肌球蛋白重链(MHC)成分与其功能特性有关.我们研究了草原田鼠的肱三头肌、胫骨前肌、腓肠肌和比目鱼肌MHC蛋白表达的性别特性.应用SDS聚丙烯酰胺凝胶电泳法测定MHC Ⅰ型、Ⅱa型、Ⅱd/x和Ⅱb型的蛋白表达相对含量.结果表明:与雌鼠相比,雄鼠的比目鱼肌湿重较大,胫骨前肌的MHC Ⅱa蛋白量表达较高.未见骨骼肌重量及MHC蛋白表达含量在雌雄鼠间的性别差异.血中睾酮的浓度差异可能不影响外周骨骼肌蛋白的表达特性.然而,与过去在大鼠、兔和小鼠中的已报道的结果相比,草原田鼠骨骼肌MHC的表达显示了更多异质性.推测这可能与草原田鼠和其它小型哺乳类动物生存的自然环境和功能需要有关.%Previous research has reported skeletal muscle protein expression characteristics for laboratory strains of various rodents, such as rats and mice. However, we do not know the muscle protein expression or sexual dimorphism characteristics of skeletal muscle for other rodents such as voles, for which the behavior, morphology, and physiology have been documented. Myosin heavy chain (MHC) content in skeletal muscle is related to functional characteristics. This study investigated sex characteristics (male,n=6; female,n=8) for MHC expression for triceps brachii, tibialis anterior, gastrocnemius, and soleus muscles in prairie voles. Relative (%) MHC protein expression was determined via SDS-PAGE for types Ⅰ, Ⅱa, Ⅱd/x, and Ⅱb MHC isoforms. Male voles had greater soleus wet weight and greater Ⅱa MHC expression for tibialis anterior as compared to those of female voles. Skeletal muscle

  15. Dietary tannic acid modulate sodium balance in root voles (Microtus oeconomus)%食物单宁酸对根田鼠(Microtus oeconomus)钠平衡的作用

    Institute of Scientific and Technical Information of China (English)

    李俊年; 陶双伦; 刘季科


    验证了单宁酸能引起植食性哺乳动物钠平衡的假设.在两种食物蛋白质水平条件下,测定了摄食含0%,3%和6%单宁酸食物的根田鼠的钠平衡和肾上腺肾小球的大小.结果表明,食物单宁酸能显著影响根田鼠的钠平衡,钠的丢失主要通过尿液.同时,单宁酸能显著影响试验个体的肾上腺肾小球的体积.初步研究显示,植食性哺乳动物对摄入的植物次生化合物的解毒引起机体钠平衡失调,而非植物次生化合物的消化抑制作用所致.%This tested the hypotheis that tannic acid can cause an imbalance of ma mmmalian hebivors.The sodium balance and the size of the zona glomerulosa of the adrenal gland was measured in root voles fed a diet containing either low or high proteins supplemented with 0, 3, or 6% of tannic acid. Relative areas of adrenal regions (zona glomerulosa, combined zona fasciculata and zona reticularis (ZFZR)) of voles fed diets containing 6% of tannic acid were increased by 9% and 7.8% for low and high protein groups, respectively, compared with those in animals fed the control diets. ZFZR/cortex of voles fed a low or high protein diet containing 3% of tannic acid were increased by 14.31% and 6.5%, respectively, as compared with those of control groups. The results indicate that addition of tannic acid to a diet can significantly induce sodium excretion mainly through urine in root voles, which may affect sodium homeostasis. These results also suggest that detoxification rather than inhibition of digestibility may primarily contribute to the sodium imbalance of mammalian herbivores that are ingesting plant secondary compounds.

  16. Comparative study of interphase cell death and severity of bone marrow aplasia in bank voles of the Moscow suburbs and C57B1 mice under the influence of ionizing radiation. [Whole-body x irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Samokhvalova, N.S.; Popova, M.F.; Domareva, O.P.; Suvorova, E.A.


    Interphase of bone marrow cells, which may reach significant dimensions according to some researchers, is one of the criteria of radiation lesion to the marrow. The method of estimating the total number of nuclear cells in animal bone marrow also makes it possible to gain an idea about the severity of tissue destruction. The objective of this work was to study interphase cell death and severity of aplasia in the bone marrow of bank voles of the Moscow suburbs and C57B1 mice after exposing these animals to x rays.

  17. The impact of early life family structure on adult social attachment, alloparental behavior, and the neuropeptide systems regulating affiliative behaviors in the monogamous prairie vole (Microtus ochrogaster

    Directory of Open Access Journals (Sweden)

    Todd H Ahern


    Full Text Available Early social attachments lie at the heart of emotional and social development in many mammals, including humans. In nature, monogamous prairie voles (Microtus ochrogaster experience considerable natural variation in early social attachment opportunities due to differences in family structure (e.g., single-mothers, solitary breeding pairs, and communal groups. We exploited some of this natural variation in family structure to examine the influence of early social environment on the development of adult social behavior. First, we characterized the parental care received by pups reared biparentally (BP or by a single-mother (SM in the laboratory. Second, we examined whether BP- and SM-reared offspring differed in adult nurturing, bonding, and emotional behaviors. Finally, we investigated the effects of rearing condition on neuropeptide systems that regulate adult social behavior (oxytocin, vasopressin, and corticotropin-releasing factor [CRF]. Observations revealed that SM-reared pups were exposed more frequently (P<0.01, licked and groomed less (P<0.01, and matured more slowly (P<0.01 than BP-reared pups. In adulthood, there were striking socio-behavioral differences: SM-reared females showed low spontaneous, pup-directed alloparental behavior (P<0.01 and both males and females from the SM-reared condition showed delayed partner preference formation. While rearing did not impact neuropeptide receptor densities in the ventral forebrain as we predicted, SM-reared animals, particularly females, had increased OT content (P<0.01 and greater dorsal raphe CRF2 densities (P<0.05 and both measures correlated with licking and grooming experienced during the first 10 days of life. These results suggest that naturalistic variation in social rearing conditions can introduce diversity into adult nurturing and attachment behaviors.

  18. Effects of the insecticide, orthene, on unconfined populations of the meadow vole (Microtus pennsylvanicus). I. Capture/recapture procedures; II. Residues and cholinesterase inhibition (United States)

    Jett, D.A.


    In 1982 and 1983. the population demography of M. pennsylvanicus was not altered significantly by single or double applications of Orthene. Although inconsistencies in population size, survival, and recruitment were not explained by differences between control and experimental grids in breeding, emigration, interspecific competition, or pesticide-induced mortality, there may have been fundamental microhabitat differences between grids in both years, and this is supported by prespray data. Slight differences between grids may also reflect the random error associated with the models used to estimate parameters. No evidence was found to indicate an effect on relative weight change or average distances moved. The level of brain AChE in 1982 during sequential days after spraying was significantly lower than control levels. However, this inhibition was not enough to cause direct mortality. Recovery of brain AChe was gradual, probably reflecting continual re-exposure through the diet. Acephate and methamidophos residues were present in the vegetation collected from sprayed areas immediately following treatment, but were reduced or absent after 8 days. AChE inhibition in 1982 and 1983 extended beyond the disappearance of residues in the vegetation. Residues were only present in the G.l. tracts of voles collected immediately following treatment due to rapid metabolism and excretion. Levels in the vegetation and G.l. tracts in 1982 and 1983 were well below the rat oral LD50 of acephate. It is concluded that Orthene applied at recommended levels, in a single or double treatment, should not affect unconfined populations of M. pennsylvanicus in Maryland old-field habitats. Furthermore, this study confirms this method as a sensitive means to determine the overall impact of insecticides on wildlife populations. However, caution must be exercised to insure that all control and experimental areas are closely scrutinized for habitat differences.

  19. Sox9 gene regulation and the loss of the XY/XX sex-determining mechanism in the mole vole Ellobius lutescens. (United States)

    Bagheri-Fam, Stefan; Sreenivasan, Rajini; Bernard, Pascal; Knower, Kevin C; Sekido, Ryohei; Lovell-Badge, Robin; Just, Walter; Harley, Vincent R


    In most mammals, the Y chromosomal Sry gene initiates testis formation within the bipotential gonad, resulting in male development. SRY is a transcription factor and together with SF1 it directly up-regulates the expression of the pivotal sex-determining gene Sox9 via a 1.3-kb cis-regulatory element (TESCO) which contains an evolutionarily conserved region (ECR) of 180 bp. Remarkably, several rodent species appear to determine sex in the absence of Sry and a Y chromosome, including the mole voles Ellobius lutescens and Ellobius tancrei, whereas Ellobius fuscocapillus of the same genus retained Sry. The sex-determining mechanisms in the Sry-negative species remain elusive. We have cloned and sequenced 1.1 kb of E. lutescens TESCO which shares 75% sequence identity with mouse TESCO indicating that testicular Sox9 expression in E. lutescens might still be regulated via TESCO. We have also cloned and sequenced the ECRs of E. tancrei and E. fuscocapillus. While the three Ellobius ECRs are highly similar (94-97% sequence identity), they all display a 14-bp deletion (Δ14) removing a highly conserved SOX/TCF site. Introducing Δ14 into mouse TESCO increased both basal activity and SF1-mediated activation of TESCO in HEK293T cells. We propose a model whereby Δ14 may have triggered up-regulation of Sox9 in XX gonads leading to destabilization of the XY/XX sex-determining mechanism in Ellobius. E. lutescens/E. tancrei and E. fuscocapillus could have independently stabilized their sex determination mechanisms by Sry-independent and Sry-dependent approaches, respectively.

  20. Mercury in soil, earthworms and organs of voles Myodes glareolus and shrew Sorex araneus in the vicinity of an industrial complex in Northwest Russia (Cherepovets). (United States)

    Komov, V T; Ivanova, E S; Poddubnaya, N Y; Gremyachikh, V A


    The characteristic properties of uptake and distribution of mercury in terrestrial ecosystems have received much lesser attention compared to aquatic particularly in Russia. Terrestrial ecosystems adjacent to large industrial manufactures-potential sources of mercury inflow into the environment frequently remain unstudied. This is the first report on mercury (Hg) levels in the basic elements of terrestrial ecosystems situated close to a large metallurgical complex.Mean values of mercury concentration (mg Hg/kg dry weight) in the vicinity of city of Cherepovets were the following: 0.056 ± 0.033-in the humus layer of soil; 0.556 ± 0.159-in earthworms; in the organs of voles Myodes glareolus (kidneys-0.021 ± 0.001; liver-0.014 ± 0.003; muscle-0.014 ± 0.001; brain-0.008 ± 0.002); in the organs of shrew Sorex araneus (kidneys-0.191 ± 0.016; liver-0.124 ± 0.011; muscle-0.108 ± 0.009; brain-0.065 ± 0.000). Correlation dependences between Hg content in soil and earthworms (r s  = 0.85, p < 0.01) as well as soil and all studied shrews' organs (rs = 0.44-0.58; p ≤ 0.01) were found.The results obtained evidence for a strong trophic link in the bioaccumulation of Hg in terrestrial food webs. Despite the vicinity to a large metallurgical complex, mercury content in the studied objects was significantly lower than values of corresponding parameters in the soils and biota from industrial (polluted) areas of Great Britain, the USA, and China.

  1. The effect of area size and predation on the time to extinction of prairie vole populations. simulation studies via SERDYCA: a Spatially-Explicit Individual-Based Model of Rodent Dynamics

    Energy Technology Data Exchange (ETDEWEB)

    Kostova, T; Carlsen, T


    We present a spatially-explicit individual-based computational model of rodent dynamics, customized for the prairie vole species, M. Ochrogaster. The model is based on trophic relationships and represents important features such as territorial competition, mating behavior, density-dependent predation and dispersal out of the modeled spatial region. Vegetation growth and vole fecundity are dependent on climatic components. The results of simulations show that the model correctly predicts the overall temporal dynamics of the population density. Time-series analysis shows a very good match between the periods corresponding to the peak population density frequencies predicted by the model and the ones reported in the literature. The model is used to study the relation between persistence, landscape area and predation. We introduce the notions of average time to extinction (ATE) and persistence frequency to quantify persistence. While the ATE decreases with decrease of area, it is a bell-shaped function of the predation level: increasing for 'small' and decreasing for 'large' predation levels.

  2. 棕色田鼠两个地域野生种群的行为比较%Intraspecific behavioral variation in two populations of wild-caught Mandarin voles

    Institute of Scientific and Technical Information of China (English)

    袁爱芳; 邰发道; 贾蕊; 翟培源; 曾爽艳; 于鹏; Hughie Broders


    小型哺乳动物能够通过行为策略的进化适应周围的环境.其中,种内社会组织也可随环境参数的变化而变化.河南灵宝程村气候干燥、海拔高,而新郑则气候湿润、海拔低.来自河南灵宝程村的棕色田鼠种群和来自新郑的种群是否在社会行为、情绪、以及性二型上有所差别,目前还不清楚.本研究中,我们通过旷场实验和熟悉选择试验比较了两个种群的情绪、运动能力以及对熟悉鼠和陌生鼠的选择.统计结果表明,程村种群的雌性个体比雄性个体重,而新郑种群的雄性体重比程村种群的重.在旷场实验中,程村种群比新郑种群表现出较多的焦虑样行为.配偶选择实验中,新郑种群不论雌雄都表现出了对陌生异性的喜好.程村种群雄性则更愿意选择熟悉的个体.而且,程村的雌性待在陌生箱攻击陌生鼠的时间远大于熟悉鼠.以上结果表明,两个野生种群在体重、情绪以及对熟悉鼠和陌生鼠选择上都表现出了明显的种群间差异.%Small mammals are likely to be able to accommodate to localized environmental shifts through the evolution of alternative behavioral strategies. Intraspecific social systems may vary considerably among populations of a species as a result of changing environmental conditions. This study examined whether behavioral traits of socially monogamous mandarin voles( Microtus mandarinus), differed between two populations (Chengcun and Xinzheng) characterized by different environmental features, namely altitude and amount of precipitation.Body mass, anxiety, locomotor activity, and partner preference of the two populations were compared. Females in the Chengcun population were much heavier compared with males. However, Xinzheng males were significantly heavier than Chengcun males. Voles in the Chengcun population spent a significantly longer period of time in the central area of an open field compared with animals in the Xinzheng


    Institute of Scientific and Technical Information of China (English)

    刘伟; 房继明


    Most of small mammals including Brandt's in temperate zone, voles(Microtus brandti), reproduce and rear offspring during seasons with mild environmental conditions and abundant food. It is assumed that animals bearing offspring during the breeding season increase their reproductive fitness and that reproduction at other periods results in fewer surviving progeny and possible energy crises for the parents. It, so that, is important that the environmental cues employed by animals to forecast the optimal breeding season are termed the proximate factors or cues of seasonal breeding. Photoperiod is the most common environmental factor used by north temperate mammals for timing reproduction. Brandt's voles' puberty and somatic growth are delayed by as many as 20 weeks in offspring late compared with early in the natural breeding season. The present study was the first measurement of some somatic and reproductive traits by comparing Brandt's voles pups born and housed in long (LD:14L:10D) versus short (SD:10L:14D) day photoperiod from birth to 28 days age or in 60 days age (The parents of LD and SD pups respectively housed exceeded 4 weeks in long and short day photoperiod after pairing). The goal was to determine whether photoperiod affect rate of growth and development of Brandt's voles offspring.   The results showed that photoperiod had no significant effect on the litter size at birth(t=1.21, df=18,P>0.05),the litter size at weaning(t=1.43,df=18,P>0.05) and the mean survival rate of pups per litter at weaning(t=1.38, df=18,P>0.05). Compared with SD pups, however, it is during eye-opening period (postnatal day 10~14) or after eye-opening (exceeded postnatal day 14) that LD offspring matured more rapidly with respect to body weight (W), body length (L) and relative fatness (Kwl=W/L) with the development of pups. Additionally, gonad-somatic index (GSI'=sin-1w\\-g/w×100%, Wg:gonad weight, W: body weight), including paired testes index (GSIt

  4. Effects of Photoperiods on Circadian Rhythm and Activity of Mandarin Voles and Kunming Mice%光周期对棕色田鼠和昆明小鼠昼夜节律及活动的影响

    Institute of Scientific and Technical Information of China (English)

    任修涛; 杨艳艳; 张宁; 王振龙; 李扬威; 路纪琪


    Photoperiods plays an important role in circadian rhythm formation and maintenance. However,random and rhythmic active circadian rhythms occurs in subterranean rodents. By using video recording and focal animal sampling methods, we tested the effect of dark-light cycles on activity rhythm in Mandarin Voles (Lasiopodomys mandarinus) and Kunming (KM) Mice (Mus musculus). The results showed that: 1 ) light duration of 28 d did not significantly influence body mass of L. mandarinus and M. musculus, respectively; 2)there were significant differences in daily activity rhythm between the two rodent species under situation of light to dark 12 h: 12 h; Mandarin Voles were active in both dark and light duration and Kunming Mice were mainly active in dark period; 3 ) L. mandarinus were little more active during time period with light, while Kunmin Mice reduced their activity frequency when light was on although both species did not change their active rhythms under full dark treatment; 4 ) M. musculus behaved a strict circadian rhythm while L. mandarinus showed a random active rhythm. The results from our research indicated that L. mandarinus has evolutionarily adapted to subterranean environment than M. musculus which derived from ground-lived ancestor.%光周期对动物昼夜节律的维持具有重要的影响,地下鼠的生活方式导致其昼夜活动节律产生变化,分化出随机活动和节律型两种模式.本文采用录像观察记录的方法,测定了棕色田鼠(Lasioposomys mandarinus)和昆明小鼠(Mus musculus)在不同光暗周期下的昼夜节律变化.结果表明:28 d的光周期变化对棕色田鼠和昆明小鼠的体重影响不显著.在12L:12D光照处理条件下,棕色田鼠的昼夜活动节律不明显,昼夜均有活动,表现为随机的活动节律模式;昆明小鼠则主要在暗周期活动,光周期极少活动,2种鼠的昼夜活动节律差异极显著.无光处理未改变棕色田鼠和昆明小鼠的同有昼夜活动节

  5. Delayed density-dependent effects and population fluctuations in the prairie vole Microtus ochrogaster%橙腹田鼠中延缓性密度依赖效应和种群波动

    Institute of Scientific and Technical Information of China (English)

    Lowell L. GETZ; Laura E. SIMMS; Joyce E. HOFMANN; Betty McGUIRE


    We tested for delayed density-dependent effects on survival and reproduction in a fluctuating population of the prairie vole Microtus ochrogaster monitored at 3.5-day intervals for 63 months. The population underwent four fluctuations in density during the study; all peaked November-January, with winter declines. Survival and reproduction displayed negative density-dependent effects, with an approximate 2-month lag time for maximum effects. There was a 2-month lag for maximum positive effects of increased survival on population density and a 3-month lag in respect to increased reproduction. Extrinsic factors, winter, may have been involved in the delayed density-dependent effects on reproduction, but we could not test for role of intrinsic factors. Seasonal effects did not appear to be responsible for the delayed density-dependent effects on survival. The net effect of the negative delayed density-dependent effects on survival and reproduction are suggested to moderate amplitudes, but not prevent, population fluctuations of M. Ochrogaster.%检验了延迟的密度依赖对橙腹田鼠(Microtus ochrogaster)一个波动种群的生存和生殖的影响,研究持续了63个月,取样间隔为3.5天.在研究期间,该种群的密度经历了4次波动,每次波动的高峰都在11月至次年1月,种群数量在冬季下降.生存和生殖都有负面的密度依赖效应,最大效应具有2个月的时滞.种群存活率增长对种群密度最大的正面效应具有2个月的时滞,而对与增加生殖则有3个月的时滞.内部因素和冬季都可能推延对生殖的密度依赖效应,但是本文未能检验这些内部因素的影响.季节性影响看来与对生存的延缓性密度依赖效应无关.负面的延缓性密度依赖效应对生存和生殖的净作用可能在于减少、而不是阻止橙腹田鼠种群波动的幅度.

  6. Social organization and mating system of free-living prairie voles Microtus ochrogaster:a review%自由生活橙腹田鼠的社会组织和婚配制度

    Institute of Scientific and Technical Information of China (English)

    Lowell L. GETZ; Betty McGUIRE; C. Sue CARTER


    在美国伊利诺伊州中东部地区对橙腹田鼠(Microtus ochrogaster)进行的广泛研究基础上,我们对该鼠的社会组织和婚配制度进行了总结. 橙腹田鼠的基本社会组织由最初的雌雄配偶或者单一的雌鼠(常为一对配偶的幸存者)与留居的后代和非亲缘成体的同居群组成.留居的后代占了原始繁殖单位之外的70%.另外,直到至少两个留居后代达到成年后,多数(80%)的非亲缘个体才加入家族群.因此,同居群的形成是以高水平的留居为基础的.雌雄配偶表现出与行为单配制有关的特征,包括共享一个巢穴和家域,雄性保卫配偶,以及双亲行为(修饰,拥抱和衔回幼鼠).同居群的成员也保卫领域[动物学报 51(2):178-186,2005].%We summarize the social organization and mating system of the prairie vole Microtus ochrogaster as determined from an extensive field study in east-central Illinois,USA. The fundamental social organization of M.ochrogaster consists of communal groups formed from an original male-female pair or single female (usually a survivor of a male-female pair) by addition of philopatric offspring and unrelated adults. Philopatric offspring comprise 70% of additions to the original breeding unit. In addition,most (80%) unrelated adults do not join a family group until at least two philopatric offspring have reached adult age. Thus,formation of communal groups is based on a high level of philopatry. Male-female pairs display traits associated with behavioral monogamy,including sharing a nest and home range,mate-guarding by the male,and paternal behavior (grooming,huddling,and retrieval of young). Members of communal groups also defend the group territory[Acta Zoologica Sinica 51(2):178-186,2005].

  7. Mice and voles prefer spruce seeds (United States)

    Herschel G. Abbott; Arthur C. Hart


    When spruce-fir stands in the Northeast are cut, balsam fir seedlings often predominate in the regeneration that follows. Most landowners would prefer to have the spruce; but they do not get it, and they wonder why.

  8. Cloning of Brandt's vole oxytocin gene and its over-expression after cell transfection on lentiviral vector%布氏田鼠催产素基因的克隆及通过慢病毒载体转染细胞后的过表达检测

    Institute of Scientific and Technical Information of China (English)

    周文君; 施海霞; 宋铭晶


    目的:构建表达布氏田鼠催产素基因的慢病毒载体及过表达检测.方法:从布氏田鼠脑组织提取RNA逆转录PCR得到OT的cDNA片段,并分别连接到带有荧光素酶(luciferase,LUC)标记的慢病毒载体PGK启动子下游,以及带有绿色荧光蛋白(EGFP)标记的EF1A启动子下游,通过这两个载体转染细胞,分别利用生物发光标记与荧光标记这两种技术示踪OT基因的表达;再通过提取RNA逆转录以及实时荧光定量PCR检测OT基因不同模板转录的拷贝数.结果:成功构建LUC标记和EGFP标记的表达布氏田鼠催产素基因的慢病毒载体,进行了真核表达检测,并建立了实时荧光定量PCR的方法.结论:催产素(oxytocin,OT)基因是哺乳动物特有的神经垂体激素,与社会认知行为和社会适应行为有关,为研究该基因的功能奠定基础.%Objective:To construct lentiviral vector of OT gene expression in Brandt's vole and detect the expression quantity and expressed area of OT gene.Methods:Total RNA extracted from brain tissue of Brandt's vole was amplified by RT-PCR for the cDNA fragments of OT gene and connected to two kinds of lentiviral vector,down stream of PGK or EF1A respectively.The two kinds of recombinant plasmid with OT gene labeling of luciferase,and eGFP marker respectivly,were transfected into 293T cells.The OT gene expression was detected in vivo by fluorescent imaging of luciferase or eGFP marker.At the same time,SYBR Green Ⅰ real-time RT-PCR system was established to detect the copy number of OT gene in different samples.Results:The lentiviral vector labeled by LUC and EGFP was successfully constructed to express oxytocin gene of Brandt's vole,and real-time fluorescent PCR method was also established to detect the copy numbers of OT gene in transgenic cells.Conclusion:Oxytocin gene is a peculiar neurohypophysial hormone of mammal,associated with social cognition behaviors and social adaption behaviors.

  9. The Recruitment of Brown Adipose Tissue and Expression of Uncoupling Protein Gene in Brandt's Vole during Cold Exposure%布氏田鼠冷暴露中褐色脂肪组织的增补及解偶联蛋白基因表达

    Institute of Scientific and Technical Information of China (English)

    王煜; 黄晨西; 等


    布氏田鼠(Microtus brandti)随机分组暴露在冷环境[12L∶12D,(4±2)℃]中12?h,1 d,3 d,7 d,14 d,21 d和28 d;对照组生活在温暖环境下[12L∶12D,(25±2)℃]。与对照组相比,布氏田鼠的褐色脂肪组织(BAT)重量在冷暴露12?h~3?d时降低,7~21?d时则增加。7~28?d冷暴露组动物的BAT总蛋白和总DNA含量均比对照组明显提高。冷环境中的布氏田鼠解偶联蛋白(UCP)的mRNA随时间的延长而表达上调,在冷暴露21?d时达到高峰。结果表明,冷暴露能够诱导布氏田鼠BAT细胞增补和UCP基因表达,从而使适应性产热增加。%Brandt' s voles (Microtus brandti) were randomly divided into seven groups and exposed to cold temperature[12L∶12D,(4±2)℃] for 12 hours,1,3 ,7,14,21 and 28 days respectively;the control group was kept in warm place [12L∶12D,(25±2)℃]. Compared with the control,the weight of BAT and the total contents of DNA in BAT decreased during cold exposure from 12 hours to 3 days,but increased significantly from 7 to 28 days. Cold exposure also induced the increase of protein contents of BAT. In molecular level,the contents of UCP mRNA in BAT increased significantly and reached peak at 21 days. The results suggested that cold exposure could induce the recruitment of BAT cell and the expression of UCP gene,resulting in the increase of adaptive thermogenesis in Brandt' s voles.

  10. Trans-equatorial migration routes, staging sites and wintering areas of a high-Arctic avian predator: the long-tailed Skua (Stercorarius longicaudus.

    Directory of Open Access Journals (Sweden)

    Olivier Gilg

    Full Text Available The Long-tailed Skua, a small (<300 g Arctic-breeding predator and seabird, is a functionally very important component of the Arctic vertebrate communities in summer, but little is known about its migration and winter distribution. We used light-level geolocators to track the annual movements of eight adult birds breeding in north-east Greenland (n = 3 and Svalbard (n = 5. All birds wintered in the Southern Hemisphere (mean arrival-departure dates on wintering grounds: 24 October-21 March: five along the south-west coast of Africa (0-40°S, 0-15°E, in the productive Benguela upwelling, and three further south (30-40°S, 0-50°E, in an area extending into the south-west Indian Ocean. Different migratory routes and rates of travel were documented during post-breeding (345 km d(-1 in late August-early September and spring migrations (235 km d(-1 in late April when most birds used a more westerly flyway. Among the different staging areas, a large region off the Grand Banks of Newfoundland appears to be the most important. It was used in autumn by all but one of the tracked birds (from a few days to three weeks and in spring by five out of eight birds (from one to more than six weeks. Two other staging sites, off the Iberian coast and near the Azores, were used by two birds in spring for five to six weeks. Over one year, individuals travelled between 43,900 and 54,200 km (36,600-45,700 when excluding staging periods and went as far as 10,500-13,700 km (mean 12,800 km from their breeding sites. This study has revealed important marine areas in both the south and north Atlantic Ocean. Sustainable management of these ocean basins will benefit Long-tailed Skuas as well as other trans-equatorial migrants from the Arctic.

  11. 自由生活的橙腹田鼠中是否有配偶选择?来自野外数据的证据%Does mate choice take place in free-living prairie voles Microtus ochrogaster?Evidence from field data

    Institute of Scientific and Technical Information of China (English)

    Lowell L. GETZ; Betty McGUIRE; Theresa PIZZUTO


    We used live-trapping data collected during a long-term study of the social organization of prairie vole Microtus ochrogaster, to investigate pair formation and break-up in this species. Most male-female pairs that formed in spring consisted of survivors of communal groups. Whether pairs formed from males and females from the same or different communal groups, the individuals were not family members. When new pairs formed during summer-autumn they typically consisted of unrelated individuals that had been wandering throughout the study site. Thus, our field data indicate that prairie voles avoided pairing with family members. We found no evidence that free-living females based their choice of mate on body mass, or that females preferred sexually experienced to sexually inexperienced males in the field or under semi-natural laboratory conditions. In our study population, pairs that separated were characterized by lower reproductive success, prior to separation, than were pairs that remained together. At any given time, the number of potential mates for males and females was limited. Thus, it seems likely that few individuals had the opportunity to compare simultaneously the characteristics of two or more potential mates. We suggest that pair formation in our study population most likely was opportunistic, with individuals pairing with the first available mate [ Acta Zoologica Sinica 50 (4): 527 - 534,2004].%使用在长期研究橙腹田鼠的社会组织中收集的数据,我们研究了该物种配对的形成和解体.大多数在春季形成的配对包括了各公社群(包括至少两个同性个体的群)过冬后的生存者.无论雌、雄个体是否来自相同或不同的的公社群,配对的个体都不是同一家庭的成员.春秋季形成的新配对,通常包括一直在研究地游荡的无亲缘关系的个体.所以,我们的野外数据表明,橙腹田鼠避免与家庭成员配对;但是没证据表明自由生活的橙腹田鼠以体重为

  12. Gender and individual information coded by insect pheromone analogs in the preputial glands in male brandt's voles Lasiopodomys brandtii%雄性布氏田鼠包皮腺中的昆虫信息素类似物编码的性别和个体信息

    Institute of Scientific and Technical Information of China (English)

    张健旭; 赵成华; 饶小平; 王大伟; 刘晓辉; 秦小薇; 张知彬


    我们利用二氯甲烷抽提和气质联用(GC-MS)比较分析了正常和阉割布氏田鼠的包皮腺分泌物(PGS)成分.我们检测到33个成分,它们几乎在所有的被测布氏田鼠都存在,其中27个成分以前报道为昆虫的信息素组分.睾丸切除不能使任何一个成分完全消失,但是显著降低了10个首先从GC-MS流失出的小分子成分,即7个饱和与不饱和的乙酸酯,一个饱和六酸酯和两个饱和八酸酯, 其中,包括PGS含量最高的成分E,E-法尼醇乙酸酯.因此,可以认为这些受睾丸调节的成分为雄性信息素的候选成分.对雌鼠的嗅觉双项选择测定说明低浓度的PGS和法尼醇乙酸酯水溶液对雌性有吸引作用,而高浓度时都具有趋避作用.这说明PGS具有剂量依赖的性吸引作用,法尼醇乙酸酯是一种剂量依赖的雄性信息素.进一步的数量比较说明,所有检测到成分的百分组成在个体间表现出巨大的个体变异,说明PGS的成分有个体的特异性,可能传递个体的嗅觉信息.%We analyzed the volatile composition of dichloromethane extracts of preputial glandular secretions (PGS) from intact and castrated male Brandt's voles Lasiopodomys brandtii by using gas chromatography-mass spectrometry (GC-MS).Thirty-three volatile compounds were detected and were present in nearly all scent donors; 27 had previously been reported as insect pheromone components. Castration did not eliminate any compounds; however, it significantly suppressed the relative quantity of ten early-eluting, low molecular weight components. These included seven saturated and unsaturated acetates, one hexanoate, and two saturated octanoates. In particular, E,E-Farnesyl acetate (FA) was the most abundant compound in the PGS. We suggest that FA and other components might be candidates for male-produced pheromones. Two-choice behavioral assays of females revealed that low concentrations of raw PGS (0.056%) and E,E-farnesyl acetate (FA) (5 parts

  13. Preparation of hydroxypropyl-β-cyclodextrin inclusion with Levonorgestrel and Quinestrol(EP-1) and its influence on the reproductive organs Brandt's voles(Lasiopodomys brandtii)%EP-1包合物制备及其对布氏田鼠繁殖器官的影响

    Institute of Scientific and Technical Information of China (English)

    王大伟; 刘琪; 刘明; 李宁; 黄宝欢; 刘晓辉


    EP series rodent contraception is mainly composed of levonorgestrel and quinestrol. However, neither compopent do not readily dissolves in water, which limits the precision of research and application. In the present study, solubilization was measured in hydroxypropyl-β-cyclodextrin ( HPCD ) inclusion complexes of levonorgestrel and quinestrol, respectively. Afterwards, the effects of treatment times ( after 2 and 4 weeks) and doses (0, 1,2, 4 mg/kg) of EP-I inclusion complexes on reproductive organs were investigated using a gastric gavage method. The results showed that the solubility of levonorgestrel and quipestrol reached 4 mg/mL and 0. 5 mg/mL in 20% aqueous HPCD solution, respectively. For females, there were no significant differences after 2 or 4 weeks between the control and treatment groups that received gavage. For males, the average weight of reproductive organs of the group that received gavage for 2 weeks of 2 mg/kg group was less than that of the control group. Our results indicate that the solubility of EP-1 was significantly enhanced by forming inclusion complexes with HPCD; the suppressive effects on reproduction in male Brandt's voles is more obvious than those in females. Moreover, inclusion did not affect the anti-fertility effect of EP-1.%EP系列鼠类不育剂的主要成分--左炔诺孕酮和炔雌醚在常温下难溶于水,给研究和应用造成很大不便.本研究利用2-羟丙基-β-环糊精(HPCD)提高了EP不育剂的水溶性,制备包合物;设置4个浓度梯度的EP-1包合物水溶液,分别对雌雄布氏田鼠进行灌胃,并在第2周和第4周测量繁殖器官指标,评价不育效果.结果表明,在20%的HPCD水溶液中,左炔诺孕酮和炔雌醚的溶解度分别可达约4 mg/mL和0.5 mg/mL;在第2周,2 mg/kg EP-1灌胃组雄鼠的繁殖器官受到了明显抑制,但各剂量组雌鼠未表现出明显影响.本研究结果说明,HPCD与EP-1可通过形成包合物,显著增加其常温下的溶解度;EP-1

  14. Developmental exposure to vasopressin increases aggression in adult prairie voles



    Although the biological roots of aggression have been the source of intense debate, the precise physiological mechanisms responsible for aggression remain poorly understood. In most species, aggression is more common in males than females; thus, gonadal hormones have been a focal point for research in this field. Although gonadal hormones have been shown to influence the expression of aggression, in many cases aggression can continue after castration, indicating that testicular steroids are n...

  15. Hantavirus testing in small mammal populations of northcentral New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Biggs, J.; Bennett, K.; Foxx, T. [and others


    In 1993, an outbreak of a new strain of hantavirus in the southwestern US indicated that deer mice (Peromyscus maniculatus) was the primary carrier of the virus. In 1993 and 1994, the Ecological Studies Team (EST) at Los Alamos National Laboratory surveyed small mammal populations in Los Alamos County, New Mexico, primarily for ecological risk assessment (ecorisk) studies. At the request of the Centers for Disease Control (CDC) and the School of Medicine at the University of New Mexico, EST also collected blood samples from captured animals for use in determining seroprevalence of hantavirus in this region due to the recent outbreak of this virus in the four-comers region of the Southwest. The deer mouse was the most commonly captured species during the tripping sessions. Other species sampled included harvest mice (Reithrodontomys megalotis), least chipmunk (Eutamias minimus), long-tailed vole (Microtus longicaudus), Mexican woodrat (Neotoma mexicana), and brush mouse (Peromyscus boylii). The team collected blood samples from tripped animals following CDC`s suggested guidelines. Results of the 1993 and 1994 hantavirus testing identified a total overall seroprevalence of approximately 5.5% and 4.2%, respectively. The highest seroprevalence rates were found in deer mice seri (3--6%), but results on several species were inconclusive; further studies will be necessary, to quantify seroprevalence rates in those species. Seroprevalence rates for Los Alamos County were much lower than elsewhere in the region.

  16. Modelling the loss of genetic diversity in vole populations in a spatially and temporally varying environment

    DEFF Research Database (Denmark)

    Topping, Christopher John; Østergaard, Siri; Pertoldi, Cino


    incorporating explicit genetics provide a promising new approach to the evaluation of the effect of animal behaviour, and random and man-induced events on the genetic composition of populations. They also provide a new platform from which to investigate the implication of real world deviations from assumptions...

  17. Pattern of X-Y chromosome pairing in the Taiwan vole, Microtus kikuchii. (United States)

    Mekada, K; Harada, M; Lin, L K; Koyasu, K; Borodin, P M; Oda, S I


    Pairing of X and Y chromosomes at meiotic prophase and the G- and C-banding patterns and nucleolar organizer region (NOR) distribution were analyzed in Microtus kikuchii. M. kikuchii is closely related to M. oeconomus and M. montebelli, karyologically and systematically. The formation of a synaptonemal complex between the X and Y chromosomes at pachytene and end-to-end association at diakinesis--metaphase I are only observed in three species in the genus Microtus; M. kikuchii, M. oeconomus, and M. montebelli. All the other species that have been studied so far have had asynaptic X-Y chromosomes. These data confirm that M. kikuchii, M. oeconomus, and M. montebelli are very closely related, and support the separation of asynaptic and synaptic groups on the phylogenetic tree.

  18. Retroelements (LINEs and SINEs) in vole genomes: differential distribution in the constitutive heterochromatin. (United States)

    Acosta, M J; Marchal, J A; Fernández-Espartero, C H; Bullejos, M; Sánchez, A


    The chromosomal distribution of mobile genetic elements is scarcely known in Arvicolinae species, but could be of relevance to understand the origin and complex evolution of the sex chromosome heterochromatin. In this work we cloned two retrotransposon sequences, L1 and SINE-B1, from the genome of Chionomys nivalis and investigated their chromosomal distribution on several arvicoline species. Our results demonstrate first that both retroelements are the most abundant repeated DNA sequences in the genome of these species. L1 elements, in most species, are highly accumulated in the sex chromosomes compared to the autosomes. This favoured L1 insertion could have played an important role in the origin of the enlarged heterochromatic blocks existing in the sex chromosomes of some Microtus species. Also, we propose that L1 accumulation on the X heterochromatin could have been the consequence of different, independent and rapid amplification processes acting in each species. SINE elements, however, were completely lacking from the constitutive heterochromatin, either in autosomes or in the heterochromatic blocks of sex chromosomes. These data could indicate that some SINE elements are incompatible with the formation of heterochromatic complexes and hence are necessarily missing from the constitutive heterochromatin.

  19. A relict bank vole lineage highlights the biogeographic history of the Pyrenean region in Europe

    NARCIS (Netherlands)

    Deffontaine, Valérie; Ledevin, Ronan; Fontaine, Michaël C.; Quéré, Jean-pierre; Renaud, Sabrina; Libois, Roland; Michaux, Johan R.

    The Pyrenean region exhibits high levels of endemism suggesting a major contribution to the phylogeography of European species. But, to date, the role of the Pyrenees and surrounding areas as a glacial refugium for temperate species remains poorly explored. In the current study, we investigated the

  20. Parasitic Arthropods of Sympatric Meadow Voles and White-Footed Mice at Fort Detrick, Maryland (United States)


    and fields, and P. leuco- Schmid, Hyde, Steigerwalt & Brenner; and the pus most frequently occurs in woodland, both agent of human babesiosi-s, Babesia ...Houghton Miffin, Boston. Sonenshine, D. E., J. T. Lamb, Jr., & G. Anastos. Carroll, J. F. & J. D. Nichols. 1986. Parasitization of 1965. The distribution ... distribution lists of mites (Acari), parasitic and Florschutz, Jr., 0. & R. F. Darsie, Jr. 1960. Addi- phoretic, in the hair of wild mammals of North

  1. A novel Rickettsia species detected in Vole Ticks (Ixodes angustus) from Western Canada. (United States)

    Anstead, Clare A; Chilton, Neil B


    The genomic DNA of ixodid ticks from western Canada was tested by PCR for the presence of Rickettsia. No rickettsiae were detected in Ixodes sculptus, whereas 18% of the I. angustus and 42% of the Dermacentor andersoni organisms examined were PCR positive for Rickettsia. The rickettsiae from each tick species were characterized genetically using multiple genes. Rickettsiae within the D. andersoni organisms had sequences at four genes that matched those of R. peacockii. In contrast, the Rickettsia present within the larvae, nymphs, and adults of I. angustus had novel DNA sequences at four of the genes characterized compared to the sequences available from GenBank for all recognized species of Rickettsia and all other putative species within the genus. Phylogenetic analyses of the sequence data revealed that the rickettsiae in I. angustus do not belong to the spotted fever, transitional, or typhus groups of rickettsiae but are most closely related to "Candidatus Rickettsia kingi" and belong to a clade that also includes R. canadensis, "Candidatus Rickettsia tarasevichiae," and "Candidatus Rickettsia monteiroi."

  2. Le verbe qui vole; mot de l'enterprete (The Flying Verb; The Interpreter's Word) (United States)

    Romer, Therese


    After a brief discussion on the nature of the interpreter's work, a survey is made of the beginnings of interpreting as a profession in 1953 and its growth since then in North America and Europe. Attention is called to the problem of incompetence brought about by the growing number of interpreters; and to the need for professional interpreter…

  3. Effectiveness of two trapping protocols for studying the demography of common voles

    Directory of Open Access Journals (Sweden)

    Eva Janova


    Full Text Available Efficacia di due metodi di trappolaggio per lo studio della demografia dell’arvicola campestre.
    Per valutare l'efficacia di due tipi di trappole, trappole “killer” e trappole “a vivo” tipo Rödl, sono stati confrontati i risultati della rimozione completa di una popolazione di arvicola campestre Microtus arvalis in merito a età, sesso, status riproduttivo e peso degli individui trappolati tramite ciascun metodo. Le trappole Rödl hanno catturato, in media, animali di età maggiore e più femmine riproduttive, mentre non sono state rilevate differenze significative in termini sia di rapporto sessi sia di peso medio. I risultati ottenuti suggeriscono di utilizzare almeno due metodi di cattura e che il confronto dei parametri demografici di popolazioni differenti può essere considerato valido solo quando siano stati utilizzati gli stessi metodi di trappolaggio.

  4. The Effect of Small-Size Habitat Disturbances on Population Density and Time to Extinction of the Prairie Vole

    Energy Technology Data Exchange (ETDEWEB)

    Kostova, T; Carlsen, T


    We present a study, based on simulations with SERDYCA, a spatially-explicit individual-based model of rodent dynamics, on the relation between population persistence and the presence of numerous isolated disturbances in the habitat. We are specifically interested in the effect of disturbances that do not fragment the environment on population persistence. Our results suggest that the presence of disturbances in the absence of fragmentation can actually increase the average time to extinction of the modeled population. The presence of disturbances decreases population density but can increase the chance for mating in monogamous species and consequently, the ratio of juveniles in the population. It thus provides a better chance for the population to restore itself after a severe period with critically low population density. We call this the ''disturbance-forced localization effect''.

  5. Post-Hoc Pattern-Oriented Testing and Tuning of an Existing Large Model: Lessons from the Field Vole

    DEFF Research Database (Denmark)

    Topping, Christopher John; Dalkvist, Trine; Grimm, Volker


    between landscape and individual behavior. Results of fitting to the range of patterns chosen were generally very good, but the procedure required to achieve this was long and complicated. To obtain good correspondence between model and the real world it was often necessary to model the real world...... environment closely. We therefore conclude that post-hoc POM is a useful and viable way to test a highly complex simulation model, but also warn against the dangers of over-fitting to real world patterns that lack details in their explanatory driving factors. To overcome some of these obstacles we suggest...

  6. Strong pituitary and hypothalamic responses to photoperiod but not to 6-methoxy-2-benzoxazolinone in female common voles (Microtus arvalis)

    NARCIS (Netherlands)

    Krol, Elzbieta; Douglas, Alex; Dardente, Hugues; Birnie, Mike J.; van der Vinne, Vincent; Eijer, Willem G.; Gerkema, Menno P.; Hazlerigg, David G.; Hut, Roelof A.; Król, Elżbieta


    The annual cycle of changing day length (photoperiod) is widely used by animals to synchronise their biology to environmental seasonality. In mammals, melatonin is the key hormonal relay for the photoperiodic message, governing thyroid-stimulating hormone (TSH) production in the pars tuberalis (PT)

  7. [Evaluation of abundance of residents and immigration by irretrievable requisitioning of the bank vole (Myodes glareolus Schreber, 1780)]. (United States)

    Shchipanov, N A; Liapina, M G


    The activity of average statistical species was approximated by normal distribution. This is provided by calculation of the part of resident animals without repeated hatching, i.e., the edge effect. Residence beyond the space covering 99% of species activity was considered as nonresidence. The appearance of nonresidence in general can be considered as "excursions" and "resettlement." The experiments on requisitioning of small settled animals from a preliminary marked site were carried out. It was shown that the number of settled small animals calculated using results of requisitioning corresponds to the number found during labeling with amendment to the edge effect, and immigration was constant and is not initiated by requisitioning. Only resettlements had an influence on the settlement of free space. The expected velocity of settling of the free space was calculated according to evaluation of the value of settlement and the share of "migrants" among immigrants. Second labeling of the place of hatching has shown that the expected and real paces of settlement are close.

  8. Development of Type 1 Diabetes in Wild Bank Voles Associated With Islet Autoantibodies and the Novel Ljungan Virus

    DEFF Research Database (Denmark)

    Niklasson, Bo; Heller, Knud Erik; Schønecker, Bryan


    Clethrionomys Glareolus, Glutamic Acid Decarboxylase Autoantibodies, IA-2 Autoantibodies, Insulin Autoantibodies, Insulin-Dependent Diabetes Mellitus, Ljungan Virus, Parechovirus, Picorna Virus......Clethrionomys Glareolus, Glutamic Acid Decarboxylase Autoantibodies, IA-2 Autoantibodies, Insulin Autoantibodies, Insulin-Dependent Diabetes Mellitus, Ljungan Virus, Parechovirus, Picorna Virus...

  9. Strong pituitary and hypothalamic responses to photoperiod but not to 6-methoxy-2-benzoxazolinone in female common voles (Microtus arvalis)

    NARCIS (Netherlands)

    Krol, Elzbieta; Douglas, Alex; Dardente, Hugues; Birnie, Mike J.; van der Vinne, Vincent; Eijer, Willem G.; Gerkema, Menno P.; Hazlerigg, David G.; Hut, Roelof A.; Król, Elżbieta


    The annual cycle of changing day length (photoperiod) is widely used by animals to synchronise their biology to environmental seasonality. In mammals, melatonin is the key hormonal relay for the photoperiodic message, governing thyroid-stimulating hormone (TSH) production in the pars tuberalis (PT)

  10. Behavioral Responses to Combinations of Timed Light, Food Availability, and Ultradian Rhythms in the Common Vole (Microtus arvalis)

    NARCIS (Netherlands)

    van der Veen, Daan R.; Saaltink, Dirk-Jan; Gerkema, Menno P.


    Light is the main entraining signal of the central circadian clock, which drives circadian organization of activity. When food is made available during only certain parts of the day, it can entrain the clock in the liver without changing the phase of the central circadian clock. Although a hallmark

  11. Impact of behavior on central and peripheral circadian clocks in the common vole Microtus arvalis, a mammal with ultradian rhythms

    NARCIS (Netherlands)

    van der Veen, DR; Le Minh, N; Gos, P; Arneric, M; Gerkema, MP; Schibler, U; Takahashi, Joseph S.


    In most mammals, daily rhythms in physiology are driven by a circadian timing system composed of a master pacemaker in the suprachiasmatic nucleus (SCN) and peripheral oscillators in most body cells. The SCN clock, which is phase-entrained by light-dark cycles, is thought to synchronize subsidiary o

  12. Quand la relation biographique vole en éclats. Renaissances. Vivre avec Joyce, Aquin, Yourcenar de Guylaine Massoutre

    Directory of Open Access Journals (Sweden)

    Frances Fortier


    Full Text Available L’ouvrage récent de Guylaine Massoutre, Renaissances. Vivre avec Joyce, Aquin, Yourcenar présente, à la faveur d’une prose échevelée et lyrique, volontiers baroque, le parcours d’une biographe fictive, elle-même personnage d’une fiction d’Aquin, sur les traces des figures littéraires qui ont déclenché son envie d’écrire. L’étude entend montrer comment cet ouvrage joue avec finesse des ancrages générique, énonciatif, culturel et esthétique de l’exercice biographique. With the help of an unbridled and lyrical prose that is wilfully baroque, the recent work of Guylaine Massoutre, entitled Renaissances. Vivre avec Joyce, Aquin, Yourcenar, presents the course of a fictitious biographer, herself a character of an Aquinian fiction, as she follows the traces of the literary figures who inspired her desire to write. This study intends to show the way in which the work plays ingeniously upon the generic, enunciative, cultural and aesthetic foundations of the biographical endeavour.


    The perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Concl...

  14. Echinococcus multilocularis infection in the field vole (Microtus agrestis)an ecological model for studies on transmission dynamics

    DEFF Research Database (Denmark)

    Woolsey, Ian David; Bune, Nethe Eva Touborg; Jensen, Per Moestrup


    necrosis factor (TNF) production in spleen cells was demonstrated by a positive correlation between corticosterone levels and higher lesion counts and TNF production in C57BL/6j, respectively. These results suggest that M. agrestis is more prone to a Th2 immune response than C57BL/6j, which is associated...

  15. 布氏田鼠行为谱的构建%Construction for the Ethogram of Brandt's Voles (Lasiopodomys brandtii)

    Institute of Scientific and Technical Information of China (English)

    王涛涛; 白玛次仁; 海淑珍; 王登


    通过摄像回放的方式对内蒙古锡林郭勒盟典型草原区野外围栏内和室内观察箱内布氏田鼠(Lasiopodomys brandtii)行为进行观察记录,按照其生活习性和各行为的生物学意义,将生态功能相近的行为归类,构建了布氏田鼠的行为谱,并分别分析了观察箱内和围栏内、不同生殖期、不同发育期和主要活动时期的行为模式的差异.结果表明:布氏田鼠的行为谱被分为个体行为和社会行为2大类,个体行为包括运动行为、摄食行为、非社会性探究行为、排泄行为、警戒行为、维持行为和筑巢行为;社会行为包括友好行为、对抗行为、繁殖行为和杀婴行为.统计数据结果显示,观察箱内运动行为和警戒行为发生频率较围栏内显著降低,非社会性探究行为、自我修饰和友好行为发生频率显著升高;观察箱内哺乳期布氏田鼠繁殖行为、筑巢行为频次较发情期和怀孕期显著增长;幼体摄食行为显著高于亚成体和成体;围栏内秋季布氏田鼠的筑巢行为频次显著增长.

  16. Fox defecation behaviour in relation to spatial distribution of voles in an urbanised area: An increasing risk of transmission of Echinococcus multilocularis? (United States)

    Robardet, E; Giraudoux, P; Caillot, C; Augot, D; Boue, F; Barrat, J


    Urbanisation of alveolar echinococcosis is a new phenomenon that has been highlighted during the last few decades. It has thus become necessary to understand the dynamics of transmission of Echinococcus multilocularis in urbanised areas. Spatial heterogeneity of infection by E. multilocularis has been explained as the result of a multifactorial dependence of the transmission in which the factors depend on the scale of the investigation. The aim of this study was to assess, in an urbanised area, the effect of such environmental factors as season, habitat type and the level of urbanisation, on the availability of two major intermediate hosts (Microtus spp. and Arvicola terrestris), the distribution of red fox faeces and the distribution of E. multilocularis as determined by detection of coproantigens in faeces. Results of the study revealed higher densities of Microtus spp. in rural than in peri-urban areas. Moreover this species was highly aggregated in urban wasteland. Arvicola terrestris densities did not appear to be linked to the level of urbanisation or to the type of habitat studied. Distribution of faeces was positively linked to distance walked and to Microtus spp. and A. terrestris distributions whatever the level of urbanisation. Such a distribution pattern could enhance the transmission cycle in urban areas. The Copro-ELISA test results on faeces collected in the field revealed that ODs were significantly negatively correlated with the abundance of A. terrestris. The larger population densities of Microtus spp. found in urban wastelands and the well known predominance of Microtus spp. in the red fox diet in the region suggest that Microtus spp. may play a key role in urban transmission of the parasite in the study area.

  17. Ambient temperature shapes reproductive output during pregnancy and lactation in the common vole (Microtus arvalis) : a test of the heat dissipation limit theory

    NARCIS (Netherlands)

    Simons, Mirre J. P.; Reimert, Inonge; van der Vinne, Vincent; Hambly, Catherine; Vaanholt, Lobke M.; Speakman, John R.; Gerkema, Menno P.


    The heat dissipation limit theory suggests that heat generated during metabolism limits energy intake and, thus, reproductive output. Experiments in laboratory strains of mice and rats, and also domestic livestock generally support this theory. Selection for many generations in the laboratory and in

  18. The role of early life experience and species differences in alcohol intake in microtine rodents. (United States)

    Anacker, Allison M J; Ahern, Todd H; Young, Larry J; Ryabinin, Andrey E


    Social relationships have important effects on alcohol drinking. There are conflicting reports, however, about whether early-life family structure plays an important role in moderating alcohol use in humans. We have previously modeled social facilitation of alcohol drinking in peers in socially monogamous prairie voles. We have also modeled the effects of family structure on the development of adult social and emotional behaviors. Here we assessed whether alcohol intake would differ in prairie voles reared by both parents compared to those reared by a single mother. We also assessed whether meadow voles, a closely related species that do not form lasting reproductive partnerships, would differ in alcohol drinking or in the effect of social influence on drinking. Prairie voles were reared either bi-parentally (BP) or by a single mother (SM). BP- and SM-reared adult prairie voles and BP-reared adult meadow voles were given limited access to a choice between alcohol (10%) and water over four days and assessed for drinking behavior in social and non-social drinking environments. While alcohol preference was not different between species, meadow voles drank significantly lower doses than prairie voles. Meadow voles also had significantly higher blood ethanol concentrations than prairie voles after receiving the same dose, suggesting differences in ethanol metabolism. Both species, regardless of rearing condition, consumed more alcohol in the social drinking condition than the non-social condition. Early life family structure did not significantly affect any measure. Greater drinking in the social condition indicates that alcohol intake is influenced similarly in both species by the presence of a peer. While the ability of prairie voles to model humans may be limited, the lack of differences in alcohol drinking in BP- and SM-reared prairie voles lends biological support to human studies demonstrating no effect of single-parenting on alcohol abuse.

  19. Das Verhalten der Schneemaus : (Chionomys nivalis)


    Niederer, Arlette


    1. Biology of the snow vole The snow vole (Chionomys nivalis) belongs to the family of voles (Arvicolidae). Within the Microtus genus it constitutes its own sub-genus (Chionomys), of which it is the only representative. The territory in which it appears is vast, ranging from the northwest of Spain to Turkmenistan and from the Carpathian Mountains to Lebanon, but its appearance is generally limited to small residual areas. The Alps constitute the largest area of cohesive occu...

  20. The role of early life experience and species differences in alcohol intake in microtine rodents.

    Directory of Open Access Journals (Sweden)

    Allison M J Anacker

    Full Text Available Social relationships have important effects on alcohol drinking. There are conflicting reports, however, about whether early-life family structure plays an important role in moderating alcohol use in humans. We have previously modeled social facilitation of alcohol drinking in peers in socially monogamous prairie voles. We have also modeled the effects of family structure on the development of adult social and emotional behaviors. Here we assessed whether alcohol intake would differ in prairie voles reared by both parents compared to those reared by a single mother. We also assessed whether meadow voles, a closely related species that do not form lasting reproductive partnerships, would differ in alcohol drinking or in the effect of social influence on drinking. Prairie voles were reared either bi-parentally (BP or by a single mother (SM. BP- and SM-reared adult prairie voles and BP-reared adult meadow voles were given limited access to a choice between alcohol (10% and water over four days and assessed for drinking behavior in social and non-social drinking environments. While alcohol preference was not different between species, meadow voles drank significantly lower doses than prairie voles. Meadow voles also had significantly higher blood ethanol concentrations than prairie voles after receiving the same dose, suggesting differences in ethanol metabolism. Both species, regardless of rearing condition, consumed more alcohol in the social drinking condition than the non-social condition. Early life family structure did not significantly affect any measure. Greater drinking in the social condition indicates that alcohol intake is influenced similarly in both species by the presence of a peer. While the ability of prairie voles to model humans may be limited, the lack of differences in alcohol drinking in BP- and SM-reared prairie voles lends biological support to human studies demonstrating no effect of single-parenting on alcohol abuse.

  1. Comparison of social interaction and neural activation in the main olfactory bulb and the accessory olfactory bulb between Microtus mandarinus and Microtus fortis

    Directory of Open Access Journals (Sweden)

    Fadao TAI, Wanying WANG, Hugh BRODERS, Ruyong SUN, Limin LIU , Hongyuan WANG


    Full Text Available To gain insight into the function of AOB and MOB during different social interaction and in different vole species, the behaviors and neural activation of the olfactory bulbs in social interactions of mandarin voles Microtus mandarinus and reed voles Microtus fortis were compared in the present research. Mandarin voles spent significantly more time attacking and sniffing its opponent and sniffing sawdust than reed voles. During same sex encounters, mandarin voles attacked its opponent for a significantly longer time and sniffed its opponent for shorter time compared with male-female interactions. However, no significant behavioral differences were found during encounters of two individual reed voles, regardless of gender composition of the pair. Using c-Fos as an indicator of neural activation, we observed that neural activation was significantly higher in almost all sub-regions of the main olfactory bulb (MOB and the accessory olfactory bulb (AOB of mandarin voles compared with reed voles. Numbers of c-Fos-ir neurons in almost all sub-regions of the AOB and the MOB during male-female interactions were also higher than those in interactions of the same sex. Anterior-posterior ratios of Fos-ir neurons in the AOBM (AOBMR and the AOBG (AOBGR in male-female interaction were significantly higher than those in interaction of the same sex. The AOBMR of male mandarin voles and reed voles were larger than those of females in male-female interactions. Behavioral patterns are consistent with cellular activity patterns. Consistent level of neural activation in MOB and AOB suggests important roles of both the main olfactory bulb and the accessory olfactory bulb in social interaction in two species [Current Zoology 55(4: 279 –287, 2009].

  2. 四种群东方田鼠线粒体DNA D-loop多态性研究%Study on Sequence Variation of Mitochondrial D-loop Gene and Polymorphism among four populations of Reed Vole (Microtus fortis)

    Institute of Scientific and Technical Information of China (English)

    谢建云; 冯洁; 柏熊; 胡建华; 高诚


    目的 探讨我国不同地区东方田鼠线粒体DNA D-loop多态性.方法 对四个种群东方田鼠线粒体DNA(mt DNA)D-loop片段进行测序,并对测序结果用Clustal W软件进行比对,通过MEGA Version3.1软件构建基于平均遗传距离的NJ(neighbor-joining,邻接法)分子系统进化树,用Dnasp4.0分析所有序列的多态位点、核苷酸多样性、单倍型数目、单倍型多样性以及进行Tajima's中性显著性检验.结果 四个种群34个东方田鼠个体的mtDNA D-loop区全序列共发现19个单倍型,单倍型比例为55.88%,单倍型多样性和核苷酸多样性分别为0.934±0.024和0.04334±0.00285.以台湾田鼠(Microtus kikuchii)线粒体全序列(GenBank登录号AF348082)为对照,共检测到核苷酸变异位点172个,约占核苷酸总教的18.66%.由分子系统进化树可发现所有34只东方田鼠分为两大类,小体型黑龙江东方田鼠为一类,其他三个种群东方田鼠为另外一类,在这一类别中,又有两个分支,其中所有宁夏种群鼠及3只大体型黑龙江种群鼠为一个分支,所有洞庭湖种群鼠和其他5只大体型黑龙江种群鼠为另一个分支.结论 我国东方田鼠在mt DNA D-loop片段存在种内遗传多态性,种群内和种群间都存在一定的遗传变异,并且黑龙江小体型种群东方田鼠表现出与其他三种群东方田鼠更大的差异水平.

  3. Relationship Between Metabolic Rate and Organ Size in Brandt's Voles (Microtus brandti)%内蒙古草原布氏田鼠代谢率与身体器官的关系

    Institute of Scientific and Technical Information of China (English)

    宋志刚; 王德华


    动物代谢率存在差异的原因及其意义是进化生理学的一个核心问题.为了解代谢率的影响因素和功能意义,我们测定了不同驯化条件下布氏田鼠(Microtus brandti)的基础代谢率 (basal metabolic rate, BMR) 、日能量消耗(daily energy expenditure, DEE)和冷诱导的最大代谢率 (maximum metabolic rate, MMR) ,分析了动物体内11种器官、组织的重量与代谢率的关系.结果显示,排除温度、光照、食物质量和体重的影响后,BMR与心脏、肝脏、肾脏、胃和盲肠相关;DEE与心脏、肾脏、胃和盲肠相关;MMR与脑重显著负相关.这表明:在布氏田鼠体内存在着代谢活性器官,主要包括心脏、肝脏、肾脏、胃和盲肠,这些器官对BMR有较大的贡献.动物的能量周转水平与体内 "代谢机器"(metabolic machinery)的大小相关连,主要受到心脏、肾脏、胃和盲肠的影响.最大代谢率受脑重的影响.BMR与MMR的相关性不显著,而BMR与DEE的相关性显著,说明较高的BMR有助于维持较高的DEE,但不能维持较高的MMR.

  4. 鼠类种群动态:食物资源影响力的实验评估%Dynamics of vole populations: an experimental evaluation of the influence of food resources

    Institute of Scientific and Technical Information of China (English)

    Lowell L. Getz; Arpat Ozgul; Madan K. Oli; Joyce E. Hofmann; Betty McGuire


    We studied responses of populations of Microtus ochrogaster and M. pennsylvanicus in east-central Illinois, USA to supplemental food in intermediate (bluegrass) and low (tallgrass prairie) food habitats. Whereas amplitudes of fluctuation of M. ochrogaster were higher in supplementally fed than in control sites in intermediate food habitat, mean population densities and patterns of fluctuation did not differ between the two sites in either habitat. Mean population densities of M.pennsylvanicus were higher in supplementally fed than in control sites only in low food tallgrass habitat. Supplemental food did not positively influence survival or maturation rates of M. ochrogaster in either habitat; the proportion of reproductively active adult females and adult male body mass were higher only in supplementally fed sites in intermediate food habitat. Supplemental food did not influence any variable of M. pennsylvanicus in bluegrass, nor survival in tallgrass, whereas maturation rates were shortened and proportion reproductively active females, immigration, and male body mass were greater in supplementally fed low food habitat. We conclude that food resources play only a minor role in driving the dynamics of populations of M. ochrogaster and M. pennsylvanicus.%本研究在美国伊利诺斯州中东部测定了中等食物质量(莓系属的牧草)和低食物质量(高杆草牧场)栖息地内橙腹田鼠(Microtus ochrogaster)和草原田鼠(M.pennsylvanicus)种群对附加食物的响应.在中等食物质量栖息地内投放附加食物,橙腹田鼠种群的波动幅度高于对照样地,但同类型食物质量栖息地内,种群平均密度和波动模式无显著的差异.仅在低等食物质量的高杆草栖息地内,投放附加食物可导致草原田鼠的种群密度高于对照样地.附加食物不直接影响两种栖息地内橙腹田鼠的成活率或成熟率,在中等食物质量栖息地中投放附加食物,繁殖活跃的成熟雌性个体比例及雄性成体的体重高于对照.附加食物不影响莓系属牧草内草原田鼠,也不能影响该动物在高杆草环境中的存活率.然而,投放附加食物,可缩短低等食物质量栖息地内草原田鼠的成熟期,提高繁殖活跃雌性的比例和迁入个体比例,增加并引起雄性个体体重增加.据此,本研究证明食物资源在橙腹田鼠和草原田鼠种群动态中只起极小的作用.

  5. 多位点DNA指纹技术在保加利亚普通田鼠中的应用探讨%Studies on applicability of multilocus DNA fingerprinting in Bulgarian common vole (Microtus arvalis)

    Institute of Scientific and Technical Information of China (English)

    陈炜; Leibenguth Friedrich; 陈宏


    DNA指纹是一种重要的现代分子遗传学标记技术(Jeffreys et al.,1985),它所揭示的是生物体大量的、无遗传编码信息的、具有高度多态性的卫星DNA(Chen,1996)。这些DNA序列往往占据了生物体基因组总量的80%以上,由于它不编码蛋白基因,在系统发育过程中,通常不被自然选择和人工选择,使得生物变异积累形成个体基因组间的巨大差异。因此,DNA指纹受到生物学家的青睐,以用于生物个体和群体的基因组分析(Burke and Bruford,1987;Buitmap et al.,1991;Weising et al.,1995)。

  6. Great River Environmental Action Team (GREAT II) Upper Mississippi River (Guttenberg, Iowa to Saverton, Missouri). Appendix. Fish and Wildlife Management Work Group. (United States)


    otter, mink and nutria can also be observed, however, they are much rarer. Small mammal species typically associ- ated with moist soil ccnmunities...Onmn Mcrotus ochroqacter Prairie Vole (Xmmon Miepotus pinetorur, Woodland Vole Rare (Mndatra zibethizus Muskrat OMxn ?14yocas ier coypur Nutria Rare

  7. Host-Associated Absence of Human Puumala Virus Infections in Northern and Eastern Germany (United States)

    Drewes, Stephan; Ali, Hanan Sheikh; Saxenhofer, Moritz; Rosenfeld, Ulrike M.; Binder, Florian; Cuypers, Fabian; Schlegel, Mathias; Röhrs, Susanne; Heckel, Gerald


    Human hantavirus disease cases, caused by Puumala virus (PUUV), are mainly recorded in western and southern areas of Germany. This bank vole reservoir survey confirmed PUUV presence in these regions but its absence in northern and eastern regions. PUUV occurrence is associated with the presence of the Western bank vole phylogroup. PMID:27983499

  8. Etogram hraboše Güntherova (Microtus guentheri) se zaměřením na sociální prvky chování


    BRIXOVÁ, Lenka


    This master thesis contains detailed description of the elements of Günthers?s vole social behaviour, from agonistic, investigative, and amicable, to reproductive behaviour. Each of the observed behavioural elements is put into context, interpreted, and compared with behaviour reported from other vole or rodent species. The resulting ethogram will be helpful in future ethological studies of this species.

  9. Studies in Intelligence. Volume 53, Number 2 (Summer Supplement 2009). Intelligence in Contemporary Media: Views of Intelligence Officers (United States)


    do his utmost to deceive an enemy by the use of false colours and false signals, by making him believe that the ship was a harmless merchantman, a...plice Fraulein Nadia Vole (Vole being another perfect villain name) fits the genre stereotype of female villains who are not just evil but untrust

  10. Small mammal mycophagy response to variations in green-tree retention (United States)

    Katherine M. Jacobs; Daniel L. Luoma


    We studied the effects of six green-tree retention levels and patterns on the diets of northern flying squirrels (Glaucomys sabrinus), Townsend's chipmunks (Tamias townsendii), Siskiyou chipmunks (T. siskiyou), western red-backed voles (Myodes calijamicus), and southern red-backed voles (...

  11. [The co-occurence of Cryptosporidium parvum, Giardia spp. and helminth infections in small rodent populations]. (United States)

    Bajer, Anna; Behnke, Jerzy M; Bednarska, Małgorzata; Kuliś, Karolina; Siński, Edward


    During long-term (1998-2000) studies on rodent parasite populations in Mazury lake district there were collected and analyzed data on co-occurrence of intestinal protozoa (Cryptosporidium parvum, Giardia spp.) and helminths. There were performed 178 autopsies of common vole Microtus arvalis, 85 autopsies of yellow-necked mouse Apodemus flavicollis and 386 autopsies of bank vole Clethrionomys glareolus. Positive effect of helminth infections was found in C. glareolus. Voles infected with nematode Heligmosomum mixtum showed higher prevalence of C. parvum and Giardia spp. than voles infected with Heligmosomoides glareoli. The host age took part in these interactions and positive effect of co-occurrence was mainly observed in voles older than 3 months. The other intrinsic (host sex) or extrinsic (season and year of study) factors influenced interactions between parasites. Presented results revealed that helminth infections may facilitate chronic infections of intestinal protozoa in rodent populations.

  12. Biology of tiny animals: three new species of minute salamanders (Plethodontidae: Thorius) from Oaxaca, Mexico (United States)

    Rovito, Sean M.; García-París, Mario; Maisano, Jessica A.; Wake, David B.


    We describe three new species of minute salamanders, genus Thorius, from the Sierra Madre del Sur of Oaxaca, Mexico. Until now only a single species, T. minutissimus, has been reported from this region, although molecular data have long shown extensive genetic differentiation among geographically disjunct populations. Adult Thorius pinicola sp. nov., T. longicaudus sp. nov., and T. tlaxiacus sp. nov. are larger than T. minutissimus and possess elliptical rather than oval nostrils; T. pinicola and T. longicaudus also have longer tails. All three new species occur west of the range of T. minutissimus, which has the easternmost distribution of any member of the genus. The new species are distinguished from each other and from other named Thorius in Oaxaca by a combination of adult body size, external morphology and osteology, and by protein characters (allozymes) and differences in DNA sequences. In addition, we redescribe T. minutissimus and a related species, T. narisovalis, to further clarify the taxonomic status of Oaxacan populations and to facilitate future studies of the remaining genetically differentiated Thorius that cannot be satisfactorily assigned to any named species. Populations of all five species considered here appear to have declined dramatically over the last one or two decades and live specimens are difficult to find in nature. Thorius may be the most endangered genus of amphibians in the world. All species may go extinct before the end of this century. PMID:27896029

  13. Biology of tiny animals: three new species of minute salamanders (Plethodontidae: Thorius from Oaxaca, Mexico

    Directory of Open Access Journals (Sweden)

    Gabriela Parra-Olea


    Full Text Available We describe three new species of minute salamanders, genus Thorius, from the Sierra Madre del Sur of Oaxaca, Mexico. Until now only a single species, T. minutissimus, has been reported from this region, although molecular data have long shown extensive genetic differentiation among geographically disjunct populations. Adult Thorius pinicola sp. nov., T. longicaudus sp. nov., and T. tlaxiacus sp. nov. are larger than T. minutissimus and possess elliptical rather than oval nostrils; T. pinicola and T. longicaudus also have longer tails. All three new species occur west of the range of T. minutissimus, which has the easternmost distribution of any member of the genus. The new species are distinguished from each other and from other named Thorius in Oaxaca by a combination of adult body size, external morphology and osteology, and by protein characters (allozymes and differences in DNA sequences. In addition, we redescribe T. minutissimus and a related species, T. narisovalis, to further clarify the taxonomic status of Oaxacan populations and to facilitate future studies of the remaining genetically differentiated Thorius that cannot be satisfactorily assigned to any named species. Populations of all five species considered here appear to have declined dramatically over the last one or two decades and live specimens are difficult to find in nature. Thorius may be the most endangered genus of amphibians in the world. All species may go extinct before the end of this century.

  14. Biology of tiny animals: three new species of minute salamanders (Plethodontidae: Thorius) from Oaxaca, Mexico. (United States)

    Parra-Olea, Gabriela; Rovito, Sean M; García-París, Mario; Maisano, Jessica A; Wake, David B; Hanken, James


    We describe three new species of minute salamanders, genus Thorius, from the Sierra Madre del Sur of Oaxaca, Mexico. Until now only a single species, T. minutissimus, has been reported from this region, although molecular data have long shown extensive genetic differentiation among geographically disjunct populations. Adult Thorius pinicola sp. nov., T. longicaudus sp. nov., and T. tlaxiacus sp. nov. are larger than T. minutissimus and possess elliptical rather than oval nostrils; T. pinicola and T. longicaudus also have longer tails. All three new species occur west of the range of T. minutissimus, which has the easternmost distribution of any member of the genus. The new species are distinguished from each other and from other named Thorius in Oaxaca by a combination of adult body size, external morphology and osteology, and by protein characters (allozymes) and differences in DNA sequences. In addition, we redescribe T. minutissimus and a related species, T. narisovalis, to further clarify the taxonomic status of Oaxacan populations and to facilitate future studies of the remaining genetically differentiated Thorius that cannot be satisfactorily assigned to any named species. Populations of all five species considered here appear to have declined dramatically over the last one or two decades and live specimens are difficult to find in nature. Thorius may be the most endangered genus of amphibians in the world. All species may go extinct before the end of this century.

  15. Versuche zur Regulierung der Wühlmäuse im biologischen Obstbau


    Kelderer, Markus; Lösch, Robert; Lardschneider, Ewald; Casera, Claudio


    In the organic apple orchards in South Tyrol different voles (Fam. Arvicolidae) are the cause of big damages on the trees. At present there isn't any product listed t the annex 2b of the EC- decree 2092/91 for organic agriculture, which could control the voles efficiently. Therefore it is quite difficult to control the voles in organic orchards. It is necessary to convince European and national authorities, associations and organs of control to allow the use of suitable products. Our trial...

  16. A Systematic Design Method for Two-Variable Numeric Function Generators Using Multiple-Valued Decision Diagrams (United States)


    IEICE TRANS. INF. & SYST., VOL.E93–D, NO.8 AUGUST 2010 2059 PAPER Special Section on Multiple-Valued Logic and VLSI Computing A Systematic Design...unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 2060 IEICE TRANS. INF. & SYST., VOL.E93–D, NO.8 AUGUST...If p = 3, then l = 2, and the upper bound is 16,450. (End of Example) 2062 IEICE TRANS. INF. & SYST., VOL.E93–D, NO.8 AUGUST 2010 Definition 12: An n

  17. 78 FR 7863 - Endangered and Threatened Wildlife and Plants; Threatened Status for the Distinct Population... (United States)


    ... scavenge carrion, but also prey on small animals and birds, and eat fruits, berries, and insects (Hornocker... have food sources such as marmots, voles, and carrion (Hornocker and Hash 1981, p. 1296; Copeland...

  18. Response of small mammals to aerial applications of the nucleopolyhedrosis virus of the gypsy moth, Lymantria dispar (United States)

    R.A. Lautenschlager; H. Rothenbacher; J.D. Podgwaite


    Resident populations of white-footed mice, Peromyscus leucopus Rafinesque, red-backed voles, Clethrionomys gapperi Vigers, opossums, Didelphis marsupialis L., chipmunks, Tamias striatus L., and raccoons, Procyon lotor L., were evaluated to detect any short term effects from...

  19. Calibration of aerial surveys and determination of streamlife for coho salmon (O. kitsuch) spawning in the Gechiak River (United States)

    US Fish and Wildlife Service, Department of the Interior — Report of species distributions of voles and shrews identified by trap lines near Upinnivgik. Presented at Bristol Bay Coho Salmon workshop, February , 1986.

  20. Small rodent population synchrony in western Sweden. Effects of landscape structure

    Directory of Open Access Journals (Sweden)

    J. Loman


    Full Text Available Small rodents were captured in two regions in western Sweden. One represents an agricultural landscape were captures were made in 19 small habitat islands and in two small forests. The other represents a forest region were captures were made in four sites in a continuous forest. The captures were made for seven years. There were no clear indications of cyclicity. Within both regions, wood mice captures were in synchrony among sites. For bank voles, this was only true in the forest region and for field voles in the agricultural region. Captures of field voles were too few for analysis in the forest region. Among species, captures were not synchronous in the agricultural region but captures of wood mice and bank voles were synchronous in the forest region. These results suggest a role of landscape structure for the population dynamics of these species, rather than differences in predator function.

  1. 75 FR 67765 - Endangered and Threatened Species Permit Applications (United States)


    ..., Nevada, Utah, and New Mexico: Kanab ambersnail (Oxyloma haydeni kanabensis), Mexican long-nosed bat... texanus), Gila topminnow (Poeciliopsis occidentalis), and Hualapai Mexican vole (Microtus mexicanus..., salvage, and collect seeds of the following rare plants: Star cactus (Astrophytum asterius),...

  2. Infectivities of four isolates of Taenia taeniaeformis to various rodents. (United States)

    Nonaka, N; Iwaki, T; Okamoto, M; Ooi, H K; Oku, Y; Ohbayashi, M; Kamiya, M


    Taenia taeniaeformis were isolated from Norway rats captured at Sapporo (SRN isolate) and Kuala Lumpur, Malaysia (KRN) and from Bedford's gray red-backed voles at Toubetsu (TCR) and Abuta (ACR). SRN, KRN and TCR isolates showed similar degree of infectivity to various rodents in which cysticerci with hooks were obtained in laboratory rats, white tuberous lesions in mice and no cysts or lesions in Mongolian gerbils and voles. Contrary to this, inoculation with ACR isolate eggs resulted in strobilocerci formation in the liver of voles, but no cysts were observed in rats, mice or gerbils. This host specificity of ACR isolate to voles suggests that it might be a new species of Taenia.

  3. Identification of Two Novel Members of the Tentative Genus Wukipolyomavirus in Wild Rodents.

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    Juozas Nainys

    Full Text Available Two novel polyomaviruses (PyVs were identified in kidney and chest-cavity fluid samples of wild bank voles (Myodes glareolus and common voles (Microtus arvalis collected in Germany. All cloned and sequenced genomes had the typical PyV genome organization, including putative open reading frames for early regulatory proteins large T antigen and small T antigen on one strand and for structural late proteins (VP1, VP2 and VP3 on the other strand. Virus-like particles (VLPs were generated by yeast expression of the VP1 protein of both PyVs. VLP-based ELISA and large T-antigen sequence-targeted polymerase-chain reaction investigations demonstrated signs of infection of these novel PyVs in about 42% of bank voles and 18% of common voles. In most cases only viral DNA, but not VP1-specific antibodies were detected. In additional animals exclusively VP1-specific antibodies, but no viral DNA was detected, indicative for virus clearance. Phylogenetic and clustering analysis including all known PyV genomes placed novel bank vole and common vole PyVs amongst members of the tentative Wukipolymavirus genus. The other known four rodent PyVs, Murine PyV and Hamster PyV, and Murine pneumotropic virus and Mastomys PyV belong to different phylogenetic clades, tentatively named Orthopolyomavirus I and Orthopolyomavirus II, respectively. In conclusion, the finding of novel vole-borne PyVs may suggest an evolutionary origin of ancient wukipolyomaviruses in rodents and may offer the possibility to develop a vole-based animal model for human wukipolyomaviruses.

  4. Scavenging of rodent carcasses following simulated mortality due to field applications of anticoagulant rodenticide. (United States)

    Montaz, Julie; Jacquot, Marion; Coeurdassier, Michaël


    Worldwide, agricultural uses of anticoagulant rodenticides (ARs) cause poisonings of non-target wildlife as observed in France where bromadiolone is used to control water vole outbreaks. Following bromadiolone field application, a part of the vole population may die aboveground of the treated plots and thus, can represent an important risk of secondary poisoning for scavengers. In this study, water voles were trapped in a non-treated area and their carcasses were placed aboveground in plots located in an area where a vole outbreak occurred. Then, the environmental persistence, the diurnal and nocturnal scavenging rates of water vole carcasses were assessed in autumn 2011 and in spring 2012. The diurnal scavenger species were also identified. The environmental persistence of the carcasses to reach at least a scavenging rate of 87.5 % was 0.5-1.5 day. The average rates of diurnal and nocturnal scavenging ranged from 67 to 100 % and 5 to 100 %, respectively. They depended on the composition of the scavenger community present near the monitored plots; diurnal scavenging rates being higher with corvids than with raptors. In autumn, the red kite and the common buzzard were the main scavengers in one of the plots, what suggests a high risk of poisoning for these raptors during post-nuptial migration. So, the collection of vole carcasses after treatments and the limitations of bromadiolone applications when high densities of predators/scavengers are observed could be implemented to mitigate the risks of secondary poisoning.

  5. A highly divergent Puumala virus lineage in southern Poland. (United States)

    Rosenfeld, Ulrike M; Drewes, Stephan; Ali, Hanan Sheikh; Sadowska, Edyta T; Mikowska, Magdalena; Heckel, Gerald; Koteja, Paweł; Ulrich, Rainer G


    Puumala virus (PUUV) represents one of the most important hantaviruses in Central Europe. Phylogenetic analyses of PUUV strains indicate a strong genetic structuring of this hantavirus. Recently, PUUV sequences were identified in the natural reservoir, the bank vole (Myodes glareolus), collected in the northern part of Poland. The objective of this study was to evaluate the presence of PUUV in bank voles from southern Poland. A total of 72 bank voles were trapped in 2009 at six sites in this part of Poland. RT-PCR and IgG-ELISA analyses detected three PUUV positive voles at one trapping site. The PUUV-infected animals were identified by cytochrome b gene analysis to belong to the Carpathian and Eastern evolutionary lineages of bank vole. The novel PUUV S, M and L segment nucleotide sequences showed the closest similarity to sequences of the Russian PUUV lineage from Latvia, but were highly divergent to those previously found in northern Poland, Slovakia and Austria. In conclusion, the detection of a highly divergent PUUV lineage in southern Poland indicates the necessity of further bank vole monitoring in this region allowing rational public health measures to prevent human infections.

  6. Arctic Small Rodents Have Diverse Diets and Flexible Food Selection.

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    Eeva M Soininen

    Full Text Available The ecology of small rodent food selection is poorly understood, as mammalian herbivore food selection theory has mainly been developed by studying ungulates. Especially, the effect of food availability on food selection in natural habitats where a range of food items are available is unknown. We studied diets and selectivity of grey-sided voles (Myodes rufocanus and tundra voles (Microtus oeconomus, key herbivores in European tundra ecosystems, using DNA metabarcoding, a novel method enabling taxonomically detailed diet studies. In order to cover the range of food availabilities present in the wild, we employed a large-scale study design for sampling data on food availability and vole diets. Both vole species had ingested a range of plant species and selected particularly forbs and grasses. Grey-sided voles also selected ericoid shrubs and tundra voles willows. Availability of a food item rarely affected its utilization directly, although seasonal changes of diets and selection suggest that these are positively correlated with availability. Moreover, diets and selectivity were affected by availability of alternative food items. These results show that the focal sub-arctic voles have diverse diets and flexible food preferences and rarely compensate low availability of a food item with increased searching effort. Diet diversity itself is likely to be an important trait and has previously been underrated owing to methodological constraints. We suggest that the roles of alternative food item availability and search time limitations for small rodent feeding ecology should be investigated.Annotated Checklist of the Panarctic Flora (PAF, Vascular plants. Available at:, accessed 15.6.2012.

  7. A Preliminary Study on Effects of Kinship on Parental Care and Infanticide of Brandt's Voles (Microtus brandti)%亲缘关系与布氏田鼠双亲行为和杀婴行为关系的初探

    Institute of Scientific and Technical Information of China (English)

    于晓东; 房继明


    根据幼仔发育的5个阶段:新生(1~5日龄)、耳立(6~9日龄)、睁眼(10~14日龄)、出巢(15~20日龄)和断奶(21~24日龄),通过观察布氏田鼠对自己幼仔( r= 0.50)和非亲缘幼仔(r<0.125)的行为反应,研究亲缘关系对布氏田鼠双亲和杀婴行为的影响.结果表明:1) 新生阶段,雄鼠抚育亲仔的时间显著多于非亲缘幼仔;断奶阶段,雄鼠与亲仔相触及在巢内活动的时间也显著多于非亲缘幼仔;雄鼠在耳立、出巢和断奶阶段嗅闻非亲缘幼仔,以及在新生和睁眼阶段修饰非亲缘幼仔的时间都显著多于亲仔.2) 断奶阶段,雌鼠与亲仔相触的时间显著多于非亲缘幼仔,但在睁眼阶段修饰非亲缘幼仔,以及在新生、耳立和出巢阶段嗅闻非亲缘幼仔的时间显著多于亲仔.3) 雌雄鼠在15日龄前没有杀婴行为,15日龄后,开始对非亲缘幼仔发生杀婴行为;雌鼠杀婴行为受幼仔发育的显著影响,且杀婴频次显著高于雄鼠;雌鼠在断奶阶段对非亲缘幼仔的杀婴频次显著高于亲仔.综上所述,亲缘关系对布氏田鼠的双亲和杀婴行为有显著影响,这可能与个体间的已往经历(熟悉性等)或表现性匹配等辨别机制有关.

  8. Studies on the learning of preference of new food in rede voles ( Microtus fortis) with different nutritional status%在不同营养状态下东方田鼠对陌生食物选择学习的研究

    Institute of Scientific and Technical Information of China (English)

    李俊年; 刘季科; 陶双伦


    通过不同饥饿处理,研究了东方田鼠在不同营养状态下,对陌生食物尝试和选择的行为模式.结果表明,初次遇到陌生食物时,各处理组对陌生食物的采食量分别为饱食6.9±1.8g,饥饿组为4.8±1.6g,饥饿+食物短缺组为3.4±1.4g.各处理组动物对陌生食物的摄入量间差异极为显著( P =0.0043).饱食组、饥饿组及饥饿+食物短缺组动物初次遇到陌生食物时,所摄入的陌生食物量占总摄入量的百分比分别为72%、38%与12%.说明,在实验室条件下饱食动物较饥饿和饥饿+食物短缺的动物学习选择摄食陌生食物的倾向较强.

  9. Trophic systems and chorology: data from shrews, moles and voles of Italy preyed by the barn owl / Sistemi trofici e corologia: dati su Soricidae, Talpidae ed Arvicolidae d'Italia predati da Tyto alba (Scopoli 1769

    Directory of Open Access Journals (Sweden)

    Longino Contoli


    Full Text Available Abstract In small Mammals biogeography, available data are up to now by far too scanty for elucidate the distribution of a lot of taxa, especially with regard to the absence from a given area. In this respect, standardized quantitative sampling techniques, like Owl pellets analysis can enable not only to enhance faunistic knowledges, but also to estimate the actual absence probability of a given taxon "m", lacking from the diet of an individual raptor. For the last purpose, the relevant frequencies of "m" in the other ecologically similar sites of the same raptor species diets are averaged ($f_m$ : the relevant standard error (multiplicated by a coefficient, according to the desired degree of accuracy, in relation of the integral of probabilities subtracted ($overline{F}_m - a E$: then, the probability that a single specimen is not pertaining to "m" is obtained ($P_0 = 1 - F_m + a E$; lastly, the desiderate accuracy probability ($P_d$ is chosen. Now, "$N_d$" (the number of individuals of all prey species in a single site needed for obtain, with the desired probability, a specimen at least of "m" is obtained through $$N = frac{ln P_d}{ln P_0}$$ Obviously, every site-diet with more than "N" preyed individuals and without any "i" specimen is considered to be lacking of such taxon. A "usefulness index" for the above purposes is outlined and checked about three raptors. Some exanples about usefulness of the Owl pellet analysis method in biogeography are given, concerning Tyto alba diets in peninsular Italy about: - Sorex minutus, lacking in some quite insulated areas; - Sorex araneus (sensu stricto, after GRAF et al., 1979, present also in lowland areas in Emilia-Romagna; - Crocidura suaveolens and - Suncus etruscus, present also in the southermost part of Calabria (Reggio province; - Talpa caeca, present also in the Antiapennines of Latium (Cimini mounts; - Talpa romana, present also in the middle of Tuscany; - Clethrionomys glareolus, lacking in few small, insulated areas, but present in coastal woodlands; - Microtus (Pitymys sp., apparently lacking only in some coastal areas of Toscana and Liguria, or in some Etna slopes (Linguaglossa. Riassunto Un metodo standardizzato e quantitativo di raccolta dei dati quale l'esame delle borre di rapaci consente non solo di integrare le conoscenze faunistiche, ma pure di tentare una valutazione della probabilità di assenza di un dato taxon da un'area geografica. In proposito, vengono presentati esempi originali circa Sorex minutus, Sorex araneus, Crocidura suaveolens, Suncus etruscus, Talpa caeca, Microtus (Pitymys savii e Microtus (Pitymys multiplex in Italia peninsulare.

  10. Influence of global atmospheric change on the feeding behavior and growth performance of a mammalian herbivore, Microtus ochrogaster.

    Directory of Open Access Journals (Sweden)

    Christopher W Habeck

    Full Text Available Global atmospheric change is influencing the quality of plants as a resource for herbivores. We investigated the impacts of elevated carbon dioxide (CO2 and ozone (O3 on the phytochemistry of two forbs, Solidago canadensis and Taraxacum officinale, and the subsequent feeding behavior and growth performance of weanling prairie voles (Microtus ochrogaster feeding on those plants. Plants for the chemical analyses and feeding trials were harvested from the understory of control (ambient air, elevated CO2 (560 µl CO2 l(-1, and elevated O3 (ambient × 1.5 rings at the Aspen FACE (Free Air CO2 Enrichment site near Rhinelander, Wisconsin. We assigned individual voles to receive plants from only one FACE ring and recorded plant consumption and weanling body mass for seven days. Elevated CO2 and O3 altered the foliar chemistry of both forbs, but only female weanling voles on the O3 diet showed negative responses to these changes. Elevated CO2 increased the fiber fractions of both plant species, whereas O3 fumigation elicited strong responses among many phytochemical components, most notably increasing the carbon-to-nitrogen ratio by 40% and decreasing N by 26%. Consumption did not differ between plant species or among fumigation treatments. Male voles were unaffected by the fumigation treatments, whereas female voles grew 36% less than controls when fed O3-grown plants. These results demonstrate that global atmospheric change has the potential to affect the performance of a mammalian herbivore through changes in plant chemistry.

  11. Experimental evidence that livestock grazing intensity affects the activity of a generalist predator (United States)

    Villar, Nacho; Lambin, Xavier; Evans, Darren; Pakeman, Robin; Redpath, Steve


    Grazing by domestic ungulates has substantial impacts on ecosystem structure and composition. In grasslands of the northern hemisphere, livestock grazing limits populations of small mammals, which are a main food source for a variety of vertebrate predators. However, no experimental studies have described the impact of livestock grazing on vertebrate predators. We experimentally manipulated sheep and cattle grazing intensity in the Scottish uplands to test its impact on a relatively abundant small mammal, the field vole (Microtus agrestis), and its archetypal generalist predator, the red fox (Vulpes vulpes). We demonstrate that ungulate grazing had a strong consistent negative impact on both vole densities and indices of fox activity. Ungulate grazing did not substantially affect the relationship between fox activity and vole densities. However, the data suggested that, as grazing intensity increased i) fox activity indices tended to be higher when vole densities were low, and ii) the relationship between fox activity and vole density was weaker. All these patterns are surprising given the relative small scale of our experiment compared to large red fox territories in upland habitats of Britain, and suggest that domestic grazing intensity causes a strong response in the activity of generalist predators important for their conservation in grassland ecosystems.

  12. Contaminant exposure in relation to spatio-temporal variation in diet composition: A case study of the little owl (Athene noctua). (United States)

    Schipper, Aafke M; Wijnhoven, Sander; Baveco, Hans; van den Brink, Nico W


    We assessed dietary exposure of the little owl Athene noctua to trace metal contamination in a Dutch Rhine River floodplain area. Diet composition was calculated per month for three habitat types, based on the population densities of six prey types (earthworms, ground beetles and four small mammal species) combined with the little owl's functional response to these prey types. Exposure levels showed a strong positive relationship with the dietary fraction of earthworms, but also depended on the dietary fraction of common voles, with higher common vole fractions resulting in decreasing exposure levels. Spatio-temporal changes in the availability of earthworms and common voles in particular resulted in considerable variation in exposure, with peaks in exposure exceeding a tentative toxicity threshold. These findings imply that wildlife exposure assessments based on a predefined, average diet composition may considerably underestimate local or intermittent peaks in exposure. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Alteration of the chronic wasting disease species barrier by in vitro prion amplification (United States)

    Kurt, Timothy D.; Seelig, Davis M.; Schneider, Jay R.; Johnson, Christopher J.; Telling, Glenn C.; Heisey, Dennis M.; Hoover, Edward A.


    Chronic wasting disease (CWD) is a transmissible spongiform encephalopathy (TSE) of cervids now detected in 19 states of the United States, three Canadian provinces, and South Korea. Whether noncervid species can be infected by CWD and thereby serve as reservoirs for the infection is not known. To investigate this issue, we previously used serial protein misfolding cyclic amplification (sPMCA) to demonstrate that CWD prions can amplify in brain homogenates from several species sympatric with cervids, including prairie voles (Microtus ochrogaster) and field mice (Peromyscus spp.). Here, we show that prairie voles are susceptible to mule deer CWD prions in vivo and that sPMCA amplification of CWD prions in vole brain enhances the infectivity of CWD for this species. Prairie voles inoculated with sPMCA products developed clinical signs of TSE disease approximately 300 days prior to, and more consistently than, those inoculated with CWD prions from deer brain. Moreover, the deposition patterns and biochemical properties of protease-resistant form of PrP (PrPRES) in the brains of affected voles differed from those in cervidized transgenic (CerPrP) mice infected with CWD. In addition, voles inoculated orally with sPMCA products developed clinical signs of TSE and were positive for PrPRES deposition, whereas those inoculated orally with deer-origin CWD prions did not. These results demonstrate that transspecies sPMCA of CWD prions can enhance the infectivity and adapt the host range of CWD prions and thereby may be useful to assess determinants of prion species barriers.

  14. Silicon, endophytes and secondary metabolites as grass defenses against mammalian herbivores

    Directory of Open Access Journals (Sweden)

    Otso eHuitu


    Full Text Available Grasses have been considered to primarily employ tolerance in lieu of defense in mitigating damage caused by herbivory. Yet a number of mechanisms have been identified in grasses, which may deter feeding by grazers. These include enhanced silicon uptake, hosting of toxin-producing endophytic fungi and induction of secondary metabolites. While these mechanisms have been individually studied, their synergistic responses to grazing, as well as their effects on grazers, are poorly known. A field experiment was carried out in 5 × 5 m outdoor enclosures to quantify phytochemical changes of either endophyte-infected (E+ or endophyte-free (E- meadow fescue (Schedonorus pratensis in response to medium intensity (corresponding with densities of ca. 1200 voles / ha for 5 weeks during 3 months or heavy intensity (ca. 1200 voles / ha for 8 weeks during 3 months grazing by a mammalian herbivore, the field vole (Microtus agrestis. A laboratory experiment was then conducted to evaluate the effects of endophyte infection status and grazing history of the grass diet on vole performance. As predicted, grazing increased foliar silicon content, by up to 13 %. Grazing also increased foliar levels of phosphorous and several phenolic compounds, most notably those of the flavonols isorhamnetin-diglycoside and rhamnetin derivative. Silicon concentrations were consistently circa 16 % higher in E+ grasses than in E-grasses, at all levels of grazing. Similarly, concentrations of chlorogenic acid derivative were found to be consistently higher in E+ than in E- grasses. Female voles maintained on heavily grazed grasses suffered higher mortality rates in the laboratory than female voles fed ungrazed grass, regardless of endophyte infection status. Our results conclusively demonstrate that, in addition to tolerance, grasses employ multi-tiered, effective defenses against mammalian grazers.

  15. Molecular evolution of Puumala hantavirus in Fennoscandia: phylogenetic analysis of strains from two recolonization routes

    DEFF Research Database (Denmark)

    Asikainen, Kari; Hänninen, Tarja; Henttonen, Heikki


    have studied wild-type PUUV strains originating from areas along two postulated immigration routes of bank voles to Fennoscandia. Full-length sequences of the S RNA segment and partial sequences (nt 2168-2569) of the M segment were recovered by RT-PCR directly from bank vole tissues collected at three...... locations in Russian Karelia and one location in Denmark. Phylogenetic analysis showed that strains from Karelia and Finland belong to the same genetic lineage, supporting the hypothesis that PUUV spread to present Finland via a Karelian land-bridge. The Danish PUUV strains showed no particularly close...

  16. [TULA HANTAVIRUS IN CRIMEA]. (United States)

    Yashina, L N; Zaykovskaya, A V; Protopopova E K; Babkin, I V; Malyshev, B S; Tovpinets, N N; Evstafiev, I L


    Genetic evidence of the Tula virus (TULV) in Crimea region of Russia is presented. Based on the reverse transcription PCR and subsequent sequence analysis, a total of 4 RNA isolates of the TULV were identified from the tissue samples of the Altai voles Microtus obscurus captured in the Bakhchisaray district of the Republic Crimea. Phylogenetic analysis of the S-, M-, and L-segment sequences of the Crimean TULV strains showed that they formed distinct genetic lineage, Russia IV, in the TULV variant. New sequences were most closely related to the lineage Russia I sequences obtained from common vole (M. arvalis) captured in the Tula region in Central Russia

  17. Growth response of Larix hybrids between L. kaempferi and L. gmelinii var. japonica with altitudinal gradient

    Energy Technology Data Exchange (ETDEWEB)

    Kisanuki, Hiromitsu; Kurahashi, Akio; Takahashi, Yasuo [Tokyo Univ. Forest, Hokkaido (Japan)


    To test the adaptability of Japanese larch, Dahurian larch and their hybrid to the environment in Hokkaido, these three materials were planted and surveyed of their survival and growth for 30 years at four elevation in central Hokkaido, northern Japan. Japanese larch showed low adaptation with high mortality affected by voles at every elevation. Dahurian larch has high vole resistance but showed high mortality caused by the infection of Armillaria root rot. Hybrid could persist through low to high elevation. Only hybrid showed enough growth at the highest elevation. Stress tolerance of hybrid was confirmed under high altitudinal condition. 12 refs, 4 figs, 3 tabs

  18. The red-tailed hawk, Buteo jamaicensis, a native definitive host of Frenkelia microti (Apicomplexa) in North America. (United States)

    Upton, S J; McKown, R D


    Oral inoculation of prairie voles, Microtus ochrogaster, with coccidian sporocysts isolated from the feces of a red-tailed hawk, Buteo jamaicensis, in Kansas, USA, resulted in formation of Frenkelia microti (Apicomplexa: Sarcocystidae) tissue cysts in the brains of the voles. Five additional isolates of morphologically similar sporocysts collected from red-tailed hawks or other Buteo spp. in Kansas failed to result in detectable infections in rodents. These results are the first to verify that red-tailed hawks are natural definitive host in North America for F. microti.

  19. Yersinia philomiragia sp. n., a new member of the Pasteurella group of bacteria, naturally pathogenic for the muskrat (Ondatra zibethica) (United States)

    Jensen, W.I.; Owen, C.R.; Jellison, W.L.


    A bacterium experimentally pathogenic for muskrats (Ondatra zibethica), white mice, mountain voles (Microtus montanus), and deer mice (Peromyscus maniculatus) was isolated from the tissues of a sick muskrat captured on the Bear River Migratory Bird Refuge (Brigham City, Utah) and from four surface water samples collected within 15 miles of that point. In culture, the cells are chiefly coccoid, but in the tissues of muskrats and voles they resemble the bizarre forms of Yersinia pestis, except for their smaller size. The characteristics of the organism are described and the name Yersinia philomiragia sp. n. is proposed.

  20. A Quaternary Decision Diagram Machine: Optimization of Its Code (United States)


    2026 IEICE TRANS. INF. & SYST., VOL.E93–D, NO.8 AUGUST 2010 INVITED PAPER Special Section on Multiple-Valued Logic and VLSI Computing A Quaternary...sequentially. A straightforward method to increase the speed is to increase the clock frequency. However, this is 2028 IEICE TRANS. INF. & SYST...reduce the 2030 IEICE TRANS. INF. & SYST., VOL.E93–D, NO.8 AUGUST 2010 Fig. 9 4-address QDD machine. Fig. 10 Branch instruction for 4-address QDD

  1. Nasal aerodynamics protects brain and lung from inhaled dust in subterranean diggers, Ellobius talpinus

    NARCIS (Netherlands)

    M.P. Moshkin; D.V. Petrovski; A.E. Akulov; A.V. Romashchenko; L.A. Gerlinskaya; V.L. Ganimedov; M.I. Muchnaya; A.S. Sadovsky; I.V. Koptyug; A.A. Savelov; S. Yu Troitsky; Y.M. Moshkn; V.I. Bukhtiyarov; N.A. Kolchanov; R.Z. Sagdeev; V.M. Fomin


    textabstractInhalation of air-dispersed sub-micrometre and nano-sized particles presents a risk factor for animal and human health. Here, we show that nasal aerodynamics plays a pivotal role in the protection of the subterranean mole vole Ellobius talpinus from an increased exposure to nano-aerosols

  2. Nasal aerodynamics protects brain and lung from inhaled dust in subterranean diggers, Ellobius talpinus

    NARCIS (Netherlands)

    M.P. Moshkin; D.V. Petrovski; A.E. Akulov; A.V. Romashchenko; L.A. Gerlinskaya; V.L. Ganimedov; M.I. Muchnaya; A.S. Sadovsky; I.V. Koptyug; A.A. Savelov; S. Yu Troitsky; Y.M. Moshkn; V.I. Bukhtiyarov; N.A. Kolchanov; R.Z. Sagdeev; V.M. Fomin


    textabstractInhalation of air-dispersed sub-micrometre and nano-sized particles presents a risk factor for animal and human health. Here, we show that nasal aerodynamics plays a pivotal role in the protection of the subterranean mole vole Ellobius talpinus from an increased exposure to

  3. Luksuslik ja atraktiivne klaasikunst

    Index Scriptorium Estoniae


    Eesti klaasikunstnik Meeli Kõiva tutvustab klaasi kasutamise võimalusi. Klaasimaalist, vitraažist. Meeli Kõiva klaas-valgusskulptuur "Feuille Qui Vole" ("Kohtumine lendavate lehtede all") asub Glaston Corporation'i juhtkonna hoone fuajees Soomes, "Reactive River" Euroopa Parlamendi peahoones Brüsselis

  4. Environmental Assessment for the Proposed Construction and Operation of New Vehicle Maintenance Facility (United States)


    Buchloe dactyloides). Other common grasses include tumble grass (Schedonnardus paniculatus) and three-awn (Aristida fendleriana and A. longiseta...prairie are scarlet globe mallow (Spaeralcea coccinea), prickly pear (Opuntia macrorhiza), rabbitbrush (Chrysothamnus nauseosus), and snakeweed...tridecemlineatus), fox squirrel (Sciurus niger), deer mouse (Peromyscus maniculatus), and prairie vole (Microtus ochragaster). Common lagomorphs

  5. Multiple Synchronous Outbreaks of Puumala Virus, Germany, 2010 (United States)

    Ettinger, Jakob; Hofmann, Jorg; Enders, Martin; Tewald, Friedemann; Oehme, Rainer M.; Rosenfeld, Ulrike M.; Ali, Hanan Sheikh; Schlegel, Mathias; Essbauer, Sandra; Osterberg, Anja; Jacob, Jens; Reil, Daniela; Klempa, Boris; Ulrich, Rainer G.


    To investigate 2,017 cases of hantavirus disease in Germany, we compared 38 new patient-derived Puumala virus RNA sequences identified in 2010 with bank vole–derived small segment RNA sequences. The epidemic process was driven by outbreaks of 6 Puumala virus clades comprising strains of human and vole origin. Each clade corresponded to a different outbreak region. PMID:22932394

  6. Immunolocalization of PTHrP in the parotid glands of three rodents species: Clethrionomys glareoulus, Microtus arvalis and white Swiss mice.

    Directory of Open Access Journals (Sweden)

    Jolanta Seidel


    Full Text Available The current study was inspired by the fact that since 2004 no report had appeared on the occurrence of this peptide in healthy parotid glands of humans and animals. The objective of the current study was to investigate the immunolocalization of PTHrP in the parotid gland of three male rodents: 6 common voles (Microtus arvalis, Pallas, 1779, 6 bank voles (Clethrionomys glareoulus, Schreber, 1780 and 6 white Swiss mice, as well as to find out any species differences in the distribution of this peptide in various types of cells of the parotid gland. Immunocytochemical reactions were performed using the ABC technique with specific rabbit antibodies against human PTHrP (34-53 (CALBIOCHEM, diluted 1:70 and 1:50. We observed positive PTHrP expression in the epithelial cells of the striated duct in all the three animal species. The expression was strong in white mouse and very strong in common vole and bank vole. In all the rodent species studied, the reaction for PTHrP was granular in nature and irregularly distributed in the cytoplasm, being definitely stronger at the base and weaker at the apex of the cells. The PTHrP expression was negative in the epithelium of the intercalated duct, interlobular duct, main excretory duct, as well as in the myoepithelial cells surrounding the excretory ducts or serous acini.

  7. The effects of sex, age, season and habitat on diet of the red fox Vulpes vulpes in northeastern Poland. (United States)

    Kidawa, Dorota; Kowalczyk, Rafał


    The diet of the red fox Vulpes vulpes was investigated in five regions of northeastern Poland by stomach content analysis of 224 foxes collected from hunters. The red fox is expected to show the opportunistic feeding habits. Our study showed that foxes preyed mainly on wild prey, with strong domination of Microtus rodents, regardless of sex, age, month and habitat. Voles Microtus spp. were found in 73% of stomachs and constituted 47% of food volume consumed. Other food items were ungulate carrion (27% of volume), other mammals (11%), birds (9%), and plant material (4%). Sex- and age-specific differences in dietary diversity were found. Adult males and juvenile foxes had larger food niche breadths than adult females and their diets highly overlapped. Proportion of Microtus voles increased from autumn to late winter. Significant habitat differences between studied regions were found. There was a tendency among foxes to decrease consumption of voles with increasing percentage of forest cover. Based on our findings, red foxes in northeastern Poland can be recognized as a generalist predators, consuming easily accessible and abundant prey. However, high percentage of voles consumed regardless of age, sex, month, or habitats may indicate red fox specialization in preying on Microtus rodents.

  8. Host diversity begets parasite diversity: bird final hosts and trematodes in snail intermediate hosts (United States)

    Hechinger, R.F.; Lafferty, K.D.


    It is postulated that disease is a product of adverse habitats. Overpopulation causes overutilization of food supplies, which results in malnutrition and a decrease in resistance to diseases. Examples of such ecological relationships in populations of Canada geese, California quail, red grouse, deer, rabbits, voles, mice and lemmings are presented.

  9. The impact of disease on wildlife populations (United States)

    Herman, C.M.


    It is postulated that disease is a product of adverse habitats. Overpopulation causes overutilization of food supplies, which results in malnutrition and a decrease in resistance to diseases. Examples of such ecological relationships in populations of Canada geese, California quail, red grouse, deer, rabbits, voles, mice and lemmings are presented.

  10. Nutrient Requirements of Domestic Animals, Number 10: Nutrient Requirements of Laboratory Animals. Third Revised Edition, 1978. (United States)

    National Academy of Sciences - National Research Council, Washington, DC. Board on Agricultural and Renewable Resources.

    This report deals with the nutrient requirements of seven species of animals used extensively for biomedical research in the United States. Following an introductory chapter of general information on nutrition, chapters are presented on the nutrient requirements of the laboratory rat, mouse, gerbil, guinea pig, hamster, vole, and fishes. Each…

  11. Barn Owl (Tyto alba) and Long-Eared Owl (Asio otus) mortality along motorways in Bourgogne-Champagne: report and suggestions (United States)

    Hugues Baudvin


    The purpose of the study was to find where and why two species of owls were killed by traffic along motorways. Three different factors have an important influence on the mortality of the two owl species: the biotops crossed by motorways, the road elevation and the presence of small rodents, the Common Vole (Microtus arvalis) being most numerous. In...

  12. Molecular evolution of Puumala hantavirus in Fennoscandia: phylogenetic analysis of strains from two recolonization routes

    DEFF Research Database (Denmark)

    Asikainen, Kari; Hänninen, Tarja; Henttonen, Heikki


    Like other members of the genus Hantavirus in the family Bunyaviridae, Puumala virus (PUUV) is thought to be co-evolving with its natural host, the bank vole Clethrionomys glareolus. To gain insight into the evolutionary history of PUUV in northern Europe during the last post-glacial period, we h...

  13. Luksuslik ja atraktiivne klaasikunst

    Index Scriptorium Estoniae


    Eesti klaasikunstnik Meeli Kõiva tutvustab klaasi kasutamise võimalusi. Klaasimaalist, vitraažist. Meeli Kõiva klaas-valgusskulptuur "Feuille Qui Vole" ("Kohtumine lendavate lehtede all") asub Glaston Corporation'i juhtkonna hoone fuajees Soomes, "Reactive River" Euroopa Parlamendi peahoones Brüsselis

  14. Ultraviolet sensitivity and colour vision in raptor foraging. (United States)

    Lind, Olle; Mitkus, Mindaugas; Olsson, Peter; Kelber, Almut


    Raptors have excellent vision, yet it is unclear how they use colour information. It has been suggested that raptors use ultraviolet (UV) reflections from vole urine to find good hunting grounds. In contrast, UV plumage colours in songbirds such as blue tits are assumed to be 'hidden' communication signals, inconspicuous to raptors. This ambiguity results from a lack of knowledge about raptor ocular media transmittance, which sets the limit for UV sensitivity. We measured ocular media transmittance in common buzzards (Buteo buteo), sparrowhawks (Accipiter nisus), red kites (Milvus milvus) and kestrels (Falco tinnunculus) so that, for the first time, raptor UV sensitivity can be fully described. With this information, and new measurements of vole urine reflectance, we show that (i) vole urine is unlikely to provide a reliable visual signal to hunting raptors and (ii) blue tit plumage colours are more contrasting to blue tits than to sparrowhawks because of UV reflectance. However, as the difference between blue tit and sparrowhawk vision is subtle, we suggest that behavioural data are needed to fully resolve this issue. UV cues are of little or no importance to raptors in both vole and songbird interactions and the role of colour vision in raptor foraging remains unclear.

  15. The biology of arboreal rodents in Douglas-fir forests. (United States)

    Andrew B. Carey


    Arboreal rodents in Douglas-fir forests west of the Cascade crest in Oregon and Washington include (listed in decreasing order of dependence on trees) red tree vole (Phenacomys longicaucfus), northern flying squirrel (Glaucomys sabrinus), Douglas' squirrel (Tamiasciurus douglasii), dusky-footed woodrat...

  16. Edge Reduction for EVMDDs to Speed Up Analysis of Multi-State Systems (United States)


    for two-variable numeric function generators using multiple-valued decision diagrams,” IEICE Trans. on Information and Systems, Vol. E93-D, No. 8, pp...of multi-state systems,” IEICE Transactions on Information and Systems, Vol.E97-D, No.9, pp.2234–2242, Sept. 2014. [16] J. E. Ramirez-Marquez and D. W

  17. Analysis of BER Performance of the Spread Spectrum Communication System with Constrained Spreading Code


    長谷川, 孝明; 羽渕, 裕真


    Copyright notice. c1996 IEICE All rights reserved. "Analysis of BER Performance of the Spread Spectrum Communication System with Constrained Spreading Code"Hiromasa HABUCHI, Toshio TAKEBAYASHI, Takaaki HASEGAWA. IEICE TRANSACTIONS on Fundamentals of Electronics, Communications and Computer Sciences ,1996 Vol.E79-A No.12 pp. 2078-2080 許諾No.07RB0055.

  18. 76 FR 18684 - Endangered and Threatened Wildlife and Plants; 12-Month Finding on a Petition To List the... (United States)


    ... snails is endemic to western North America and is found in mountainous environments in the western United... voles), reptiles, amphibians, birds, and insects (Frest and Johannes 1995, p. 25). The life history of... (Baumann 1975, p. 1). In North America, family Nemouridae comprises 73 species in 13 genera (Stark et...

  19. Influence of geographical scale on the detection of density dependence in the host-parasite system, Arvicola terrestris and Taenia taeniaeformis. (United States)

    Deter, J; Berthier, K; Chaval, Y; Cosson, J F; Morand, S; Charbonnel, N


    Infection by the cestode Taenia taeniaeformis was investigated within numerous cyclic populations of the fossorial water vole Arvicola terrestris sampled during 4 years in Franche-Comté (France). The relative influence of different rodent demographic parameters on the presence of this cestode was assessed by considering (1) the demographic phase of the cycle; (2) density at the local geographical scale (10 km2). The local scale corresponded to the rodent population (intermediate host), while the large scale corresponded to the definitive host population (wild and feral cats). General linear models based on analyses of 1804 voles revealed the importance of local density but also of year, rodent age, season and interactions between year and season and between age and season. Prevalence was significantly higher in low vole densities than during local outbreaks. By contrast, the large geographical scale density and the demographic phase had less influence on infection by the cestode. The potential impacts of the cestode on the fitness of the host were assessed and infection had no effect on the host body mass, litter size or sexual activity of voles.

  20. The impact of climate and cyclic food abundance on the timing of breeding and brood size in four boreal owl species. (United States)

    Lehikoinen, Aleksi; Ranta, Esa; Pietiäinen, Hannu; Byholm, Patrik; Saurola, Pertti; Valkama, Jari; Huitu, Otso; Henttonen, Heikki; Korpimäki, Erkki


    The ongoing climate change has improved our understanding of how climate affects the reproduction of animals. However, the interaction between food availability and climate on breeding has rarely been examined. While it has been shown that breeding of boreal birds of prey is first and foremost determined by prey abundance, little information exists on how climatic conditions influence this relationship. We studied the joint effects of main prey abundance and ambient weather on timing of breeding and reproductive success of two smaller (pygmy owl Glaucidium passerinum and Tengmalm's owl Aegolius funereus) and two larger (tawny owl Strix aluco and Ural owl Strix uralensis) avian predator species using long-term nation-wide datasets during 1973-2004. We found no temporal trend either in vole abundance or in hatching date and brood size of any studied owl species. In the larger species, increasing late winter or early spring temperature advanced breeding at least as much as did high autumn abundance of prey (voles). Furthermore, increasing snow depth delayed breeding of the largest species (Ural owl), presumably by reducing the availability of voles. Brood size was strongly determined by spring vole abundance in all four owl species. These results show that climate directly affects the breeding performance of vole-eating boreal avian predators much more than previously thought. According to earlier studies, small-sized species should advance their breeding more than larger species in response to increasing temperature. However, we found an opposite pattern, with larger species being more sensitive to temperature. We argue that this pattern is caused by a difference in the breeding tactics of larger mostly capital breeding and smaller mostly income breeding owl species.

  1. [The estimation of 90Sr and 137Cs excretion parameters from the organism of wild and laboratory small mammals in vivo, after natural contamination of them in the Chernobyl zone]. (United States)

    Makliuk, Iu A; Gashchak, S P; Maksimenko, A M; Bondar'kov, M D


    In the course of laboratory experiment, parameters of 90Sr and 137Cs excretion were estimated in individuals of bank vole Clethrionomys glareolus, captured at one of the most contaminated sites of the Chernobyl zone. The animals were kept under laboratory conditions using "clean" feed during 50 days. The similar investigation was carried out with laboratory mice Mus musculus (Big Blue line) during a longer period (184 days). The measurements of 90Sr content in the animals' body were in vivo carried out, using a specially designed beta-spectrometer with appropriate software, and 137Cs one--by the gamma-spectrometer. During the experiment, the animals had lost less 0.4% of activity due to physical decay of radionuclides. The organism was depurated mainly through biological excretion. In accordance with parameters of one-component exponential decay equation, 99.3% of 137Cs initial content in vole was excreted with half-life period of 2.18 days, and mice--4.4 days (99%). 90Sr excretion had longer half-life period: 11.7 days (56%) in voles, and 49.9 days (87%) in laboratory mice. The rest radionuclides amount of given model was considered as non-excreted from the organism during the observation period. It was determined on the example of voles that 90Sr and 137Cs loss in males was faster than in females, and among females more intensive excretion was in lactating females. 137Cs excretion from the body of bank vole is mainly with urine (74.7%), whereas 90Sr one--with feces and urine in approximately equal amounts. Due to the birth of babies and consequent feeding female lose appreciably less amount of radionuclides body burden than at daily loss with urine and feces.

  2. Evidence for novel hepaciviruses in rodents.

    Directory of Open Access Journals (Sweden)

    Jan Felix Drexler

    Full Text Available Hepatitis C virus (HCV is among the most relevant causes of liver cirrhosis and hepatocellular carcinoma. Research is complicated by a lack of accessible small animal models. The systematic investigation of viruses of small mammals could guide efforts to establish such models, while providing insight into viral evolutionary biology. We have assembled the so-far largest collection of small-mammal samples from around the world, qualified to be screened for bloodborne viruses, including sera and organs from 4,770 rodents (41 species; and sera from 2,939 bats (51 species. Three highly divergent rodent hepacivirus clades were detected in 27 (1.8% of 1,465 European bank voles (Myodes glareolus and 10 (1.9% of 518 South African four-striped mice (Rhabdomys pumilio. Bats showed anti-HCV immunoblot reactivities but no virus detection, although the genetic relatedness suggested by the serologic results should have enabled RNA detection using the broadly reactive PCR assays developed for this study. 210 horses and 858 cats and dogs were tested, yielding further horse-associated hepaciviruses but none in dogs or cats. The rodent viruses were equidistant to HCV, exceeding by far the diversity of HCV and the canine/equine hepaciviruses taken together. Five full genomes were sequenced, representing all viral lineages. Salient genome features and distance criteria supported classification of all viruses as hepaciviruses. Quantitative RT-PCR, RNA in-situ hybridisation, and histopathology suggested hepatic tropism with liver inflammation resembling hepatitis C. Recombinant serology for two distinct hepacivirus lineages in 97 bank voles identified seroprevalence rates of 8.3 and 12.4%, respectively. Antibodies in bank vole sera neither cross-reacted with HCV, nor the heterologous bank vole hepacivirus. Co-occurrence of RNA and antibodies was found in 3 of 57 PCR-positive bank vole sera (5.3%. Our data enable new hypotheses regarding HCV evolution and encourage

  3. Isolation of a Defective Prion Mutant from Natural Scrapie (United States)

    Migliore, Sergio; Cosseddu, Gian Mario; Pirisinu, Laura; Riccardi, Geraldina; Nonno, Romolo


    It is widely known that prion strains can mutate in response to modification of the replication environment and we have recently reported that prion mutations can occur in vitro during amplification of vole-adapted prions by Protein Misfolding Cyclic Amplification on bank vole substrate (bvPMCA). Here we exploited the high efficiency of prion replication by bvPMCA to study the in vitro propagation of natural scrapie isolates. Although in vitro vole-adapted PrPSc conformers were usually similar to the sheep counterpart, we repeatedly isolated a PrPSc mutant exclusively when starting from extremely diluted seeds of a single sheep isolate. The mutant and faithful PrPSc conformers showed to be efficiently autocatalytic in vitro and were characterized by different PrP protease resistant cores, spanning aa ∼155–231 and ∼80–231 respectively, and by different conformational stabilities. The two conformers could thus be seen as different bona fide PrPSc types, putatively accounting for prion populations with different biological properties. Indeed, once inoculated in bank vole the faithful conformer was competent for in vivo replication while the mutant was unable to infect voles, de facto behaving like a defective prion mutant. Overall, our findings confirm that prions can adapt and evolve in the new replication environments and that the starting population size can affect their evolutionary landscape, at least in vitro. Furthermore, we report the first example of “authentic” defective prion mutant, composed of brain-derived PrPC and originating from a natural scrapie isolate. Our results clearly indicate that the defective mutant lacks of some structural characteristics, that presumably involve the central region ∼90–155, critical for infectivity but not for in vitro replication. Finally, we propose a molecular mechanism able to account for the discordant in vitro and in vivo behavior, suggesting possible new paths for investigating the molecular bases of

  4. Seed preferences by rodents in the agri-environment and implications for biological weed control. (United States)

    Fischer, Christina; Türke, Manfred


    Post-dispersal seed predation and endozoochorous seed dispersal are two antagonistic processes in relation to plant recruitment, but rely on similar preconditions such as feeding behavior of seed consumers and seed traits. In agricultural landscapes, rodents are considered important seed predators, thereby potentially providing regulating ecosystem services in terms of biological weed control. However, their potential to disperse seeds endozoochorously is largely unknown. We exposed seeds of arable plant species with different seed traits (seed weight, nutrient content) and different Red List status in an experimental rye field and assessed seed removal by rodents. In a complementary laboratory experiment, consumption rates, feeding preferences, and potential endozoochory by two vole species (Microtus arvalis and Myodes glareolus) were tested. Seed consumption by rodents after 24 h was 35% in the field and 90% in the laboratory. Both vole species preferred nutrient-rich over nutrient-poor seeds and M. glareolus further preferred light over heavy seeds and seeds of common over those of endangered plants. Endozoochory by voles could be neglected for all tested plant species as no seeds germinated, and only few intact seeds could be retrieved from feces. Synthesis and applications. Our results suggest that voles can provide regulating services in agricultural landscapes by depleting the seed shadow of weeds, rather than facilitating plant recruitment by endozoochory. In the laboratory, endangered arable plants were less preferred by voles than noxious weeds, and thus, our results provide implications for seed choice in restoration approaches. However, other factors such as seed and predator densities need to be taken into account to reliably predict the impact of rodents on the seed fate of arable plants.

  5. Concomitant influence of helminth infection and landscape on the distribution of Puumala hantavirus in its reservoir, Myodes glareolus

    Directory of Open Access Journals (Sweden)

    Henttonen Heikki


    Full Text Available Abstract Background Puumala virus, the agent of nephropathia epidemica (NE, is the most prevalent hantavirus in Europe. The risk for human infection seems to be strongly correlated with the prevalence of Puumala virus (PUUV in populations of its reservoir host species, the bank vole Myodes glareolus. In humans, the infection risks of major viral diseases are affected by the presence of helminth infections. We therefore proposed to analyse the influence of both helminth community and landscape on the prevalence of PUUV among bank vole populations in the Ardennes, a PUUV endemic area in France. Results Among the 313 voles analysed, 37 had anti-PUUV antibodies. Twelve gastro-intestinal helminth species were recorded among all voles sampled. We showed that PUUV seroprevalence strongly increased with age or sexual maturity, especially in the northern forests (massif des Ardennes. The helminth community structure significantly differed between this part and the woods or hedgerows of the southern cretes pre-ardennaises. Using PUUV RNA quantification, we identified significant coinfections between PUUV and gastro-intestinal helminths in the northern forests only. More specifically, PUUV infection was positively associated with the presence of Heligmosomum mixtum, and in a lesser extent, Aonchotheca muris-sylvatici. The viral load of PUUV infected individuals tended to be higher in voles coinfected with H. mixtum. It was significantly lower in voles coinfected with A. muris-sylvatici, reflecting the influence of age on these latter infections. Conclusions This is the first study to emphasize hantavirus - helminth coinfections in natural populations. It also highlights the importance to consider landscape when searching for such associations. We have shown that landscape characteristics strongly influence helminth community structure as well as PUUV distribution. False associations might therefore be evidenced if geographic patterns of helminths or PUUV

  6. Identification of novel anelloviruses with broad diversity in UK rodents. (United States)

    Nishiyama, Shoko; Dutia, Bernadette M; Stewart, James P; Meredith, Anna L; Shaw, Darren J; Simmonds, Peter; Sharp, Colin P


    Anelloviruses are a family of small circular ssDNA viruses with a vast genetic diversity. Human infections with the prototype anellovirus, torque teno virus (TTV), are ubiquitous and related viruses have been described in a number of other mammalian hosts. Despite over 15 years of investigation, there is still little known about the pathogenesis and possible disease associations of anellovirus infections, arising in part due to the lack of a robust cell culture system for viral replication or tractable small-animal model. We report the identification of diverse anelloviruses in several species of wild rodents. The viruses are highly prevalent in wood mice (Apodemus sylvaticus) and field voles (Microtus agrestis), detectable at a low frequency in bank voles (Myodes glareolus), but absent from house mice (Mus musculus). The viruses identified have a genomic organization consistent with other anelloviruses, but form two clear phylogenetic groups that are as distinct from each other as from defined genera.

  7. Identification of novel anelloviruses with broad diversity in UK rodents (United States)

    Nishiyama, Shoko; Dutia, Bernadette M.; Stewart, James P.; Meredith, Anna L.; Shaw, Darren J.; Simmonds, Peter


    Anelloviruses are a family of small circular ssDNA viruses with a vast genetic diversity. Human infections with the prototype anellovirus, torque teno virus (TTV), are ubiquitous and related viruses have been described in a number of other mammalian hosts. Despite over 15 years of investigation, there is still little known about the pathogenesis and possible disease associations of anellovirus infections, arising in part due to the lack of a robust cell culture system for viral replication or tractable small-animal model. We report the identification of diverse anelloviruses in several species of wild rodents. The viruses are highly prevalent in wood mice (Apodemus sylvaticus) and field voles (Microtus agrestis), detectable at a low frequency in bank voles (Myodes glareolus), but absent from house mice (Mus musculus). The viruses identified have a genomic organization consistent with other anelloviruses, but form two clear phylogenetic groups that are as distinct from each other as from defined genera. PMID:24744300

  8. Polyandrous females produce sons that are successful at post-copulatory competition. (United States)

    Klemme, I; Bäumer, J; Eccard, J A; Ylönen, H


    Some of the genetic benefit hypotheses put forward to explain multiple male mating (polyandry) predict that sons of polyandrous females will have an increased competitive ability under precopulatory or post-copulatory competition via paternally inherited traits, such as attractiveness or fertilization efficiency. Here, we tested these predictions by comparing the competitive ability of sons of experimentally monandrous and polyandrous female bank voles (Myodes glareolus), while controlling for potential material and maternal effects. In female choice experiments, we found no clear preference for sons of either monandrous or polyandrous mothers. Moreover, neither male type was dominant over the other, indicating no advantage in precopulatory male contest competition. However, in competitive matings, sons of polyandrous mothers significantly increased their mating efforts (mating duration, intromission number). In line with this, paternity success was biased towards sons of polyandrous mothers. Because there was no evidence for maternal effects, our results suggest that female bank voles gain genetic benefits from polyandry.

  9. Effects of grazing intensity on small mammal population ecology in wet meadows

    DEFF Research Database (Denmark)

    Schmidt, N.M.; Olsen, H.; Bildsøe, M.


    Livestock grazing is common management practice in wet grasslands. However, knowledge of its effects on small mammals is limited. We studied the influence of grazing intensity on small mammals in general and field voles Microtus agrestis in particular in two Danish wet meadows, 1998-2000. Generally......, grazing livestock had a negative effect on the peak biomass of small mammals, and the negative effect increased with grazing intensity, irrespective of whether pens were grazed by cattle or by sheep. More detailed analyses, however, revealed that an intermediate grazing intensity (approximately 400 kg...... ha-1 as maximum livestock biomass) actually seemed to benefit small mammals. This grazing intensity generally held small mammal biomasses and field vole population sizes that were similar to or larger than those on the ungrazed control, and markedly larger than those on the more heavily grazed pens...

  10. Age Variations in Microtus guentheri Danford and Alston, 1880 (Mammalia: Rodentia) in Turkey


    SÖZEN, Mustafa; ÇOLAK, Ercüment; Nuri YİĞİT


    The skull, teeth, phallus and bacula of Microtus guentheri specimens raised in the laboratory were investigated at different stages of postnatal development. The most of the cranial measurements attained those of adults on day 60. There were determined to be some morphological differences between the skulls of young and adult voles. The incisors and the molars began to erupt at 3 and 6 days, respectively. It was shown that there was no difference in respect to the phallic and bacular morpholo...

  11. [Taenia martis (Cestoda, Taeniidae) from vertebrates in the Republic of Belarus]. (United States)

    Shimalov, V V


    Infestation of vertebrate animals with the cestode Taenia martis and its larvae was investigated in south-west Belarus during 2001-2008. Obligatory definitive host (common marten) and intermediate hosts (red-backed vole, yellow-necked mouse, striped field mouse, and red squirrel) of this helminth were established for the Republic of Belarus. Description and figure of the T. martis larva is given.

  12. Environmental Assessment of the Privatization of Military Family Housing, Fairchild Air Force Base, Washington (United States)


    duct leakage. Attention to construction details, exterior fenestration materials, and passive solar energy systems would be employed whenever...large mammals, few small mammals (mostly deer mice, voles, and moles), and bird communities dominated by fruit -eating or omnivorous species, such as...washer, and dryer . • Hard finish flooring in kitchen, informal dining area, wet areas, and high traffic areas • Carpet in bedrooms and other living

  13. Increased autumn rainfall disrupts predator-prey interactions in fragmented boreal forests. (United States)

    Terraube, Julien; Villers, Alexandre; Poudré, Léo; Varjonen, Rauno; Korpimäki, Erkki


    There is a pressing need to understand how changing climate interacts with land-use change to affect predator-prey interactions in fragmented landscapes. This is particularly true in boreal ecosystems facing fast climate change and intensification in forestry practices. Here, we investigated the relative influence of autumn climate and habitat quality on the food-storing behaviour of a generalist predator, the pygmy owl, using a unique data set of 15 850 prey items recorded in western Finland over 12 years. Our results highlighted strong effects of autumn climate (number of days with rainfall and with temperature forests strengthened the functional response of owls to variations in vole abundance and were more prone to switch from main prey to alternative prey (passerine birds) depending on local climate conditions. High-quality habitat may allow pygmy owls to buffer negative effects of inclement weather and cyclic variation in vole abundance. Additionally, our results evidenced sex-specific trends in body condition, as the scaled mass index of smaller males increased while the scaled mass index of larger females decreased over the study period, probably due to sex-specific foraging strategies and energy requirements. Long-term temporal stability in local vole abundance refutes the hypothesis of climate-driven change in vole abundance and suggests that rainier autumns could reduce the vulnerability of small mammals to predation by pygmy owls. As small rodents are key prey species for many predators in northern ecosystems, our findings raise concern about the impact of global change on boreal food webs through changes in main prey vulnerability. © 2016 John Wiley & Sons Ltd.

  14. Relating increasing hantavirus incidences to the changing climate: the mast connection

    Directory of Open Access Journals (Sweden)

    Maes Piet


    Full Text Available Abstract Background Nephropathia epidemica (NE, an emerging rodent-borne viral disease, has become the most important cause of infectious acute renal failure in Belgium, with sharp increases in incidence occurring for more than a decade. Bank voles are the rodent reservoir of the responsible hantavirus and are known to display cyclic population peaks. We tried to relate these peaks to the cyclic NE outbreaks observed since 1993. Our hypothesis was that the ecological causal connection was the staple food source for voles, being seeds of deciduous broad-leaf trees, commonly called "mast". We also examined whether past temperature and precipitation preceding "mast years" were statistically linked to these NE outbreaks. Results Since 1993, each NE peak is immediately preceded by a mast year, resulting in significantly higher NE case numbers during these peaks (Spearman R = -0.82; P = 0.034. NE peaks are significantly related to warmer autumns the year before (R = 0.51; P Conclusion NE peaks in year 0 are induced by abundant mast formation in year-1, facilitating bank vole survival during winter, thus putting the local human population at risk from the spring onwards of year 0. This bank vole survival is further promoted by higher autumn temperatures in year-1, whereas mast formation itself is primed by higher summer temperatures in year-2. Both summer and autumn temperatures have been rising to significantly higher levels during recent years, explaining the virtually continuous epidemic state since 2005 of a zoonosis, considered rare until recently. Moreover, in 2007 a NE peak and an abundant mast formation occurred for the first time within the same year, thus forecasting yet another record NE incidence for 2008. We therefore predict that with the anticipated climate changes due to global warming, NE might become a highly endemic disease in Belgium and surrounding countries.

  15. On the contradiction between the statistical parameters of population dynamics


    Korosov Andrey


    A model simulating the dynamics of the field vole (Microtus agrestis) numerosity during one year was built. The purpose of modeling was to reproduce the values of population characteristics, averaged over a long period of field observations. It was found that long-term average population characteristics can not be observed in any one year of simulated population life. A model population with an average long-term dynamics of age structure can not sustain long-term population dynamics. Long-ter...

  16. Heterogeneous road networks have no apparent effect on the genetic structure of small mammal populations. (United States)

    Grilo, Clara; Del Cerro, Irene; Centeno-Cuadros, Alejandro; Ramiro, Victor; Román, Jacinto; Molina-Vacas, Guillem; Fernández-Aguilar, Xavier; Rodríguez, Juan; Porto-Peter, Flávia; Fonseca, Carlos; Revilla, Eloy; Godoy, José A


    Roads are widely recognized to represent a barrier to individual movements and, conversely, verges can act as potential corridors for the dispersal of many small mammals. Both barrier and corridor effects should generate a clear spatial pattern in genetic structure. Nevertheless, the effect of roads on the genetic structure of small mammal populations still remains unclear. In this study, we examine the barrier effect that different road types (4-lane highway, 2-lane roads and single-lane unpaved roads) may have on the population genetic structure of three species differing in relevant life history traits: southern water vole Arvicola sapidus, the Mediterranean pine vole Microtus duodecimcostatus and the Algerian mouse Mus spretus. We also examine the corridor effect of highway verges on the Mediterranean pine vole and the Algerian mouse. We analysed the population structure through pairwise estimates of FST among subpopulations bisected by roads, identified genetic clusters through Bayesian assignment approaches, and used simple and partial Mantel tests to evaluate the relative barrier or corridor effect of roads. No strong evidences were found for an effect of roads on population structure of these three species. The barrier effect of roads seems to be site-specific and no corridor effect of verges was found for the pine vole and Algerian mouse populations. The lack of consistent results among species and for each road type lead us to believe that the ability of individual dispersers to use those crossing structures or the habitat quality in the highway verges may have a relatively higher influence on gene flow among populations than the presence of crossing structures per se. Further research should include microhabitat analysis and the estimates of species abundance to understand the mechanisms that underlie the genetic structure observed at some sites.

  17. Hormonal and photoperiodic modulation of testicular mRNAs coding for inhibin/activin subunits and follistatin in Clethrionomys glareolus, Schreber. (United States)

    Tähkä, K M; Kaipia, A; Toppari, J; Tähkä, S; Tuuri, T; Tuohimaa, P


    Photoperiodic and hormonal modulation of mRNAs for testicular inhibin/activin subunits and follistatin were studied in a seasonally breeding rodent, the bank vole (Clethrionomys glareolus). Photoperiod-induced testicular regression had no effect on the relatively low steady-state levels of follistatin mRNA. Inhibin alpha (I alpha) and beta B (I beta B) mRNA levels were significantly higher in regressed than in active gonads, but inhibin beta A was undetectable. The effect of gonadotropin administration on testicular weight and mRNA concentrations differed between the sexually active and quiescent voles. Neither FSH (1.2 U/kg; s.c. for 5 days) nor hCG (600 IU/kg; s.c. for 5 days) affected testicular weight in sexually active voles, whereas both gonadotropins significantly increased testicular weight in photo-regressed individuals. FSH had no effect on I alpha or I beta B mRNA concentrations in the active testes, whereas excessive hCG challenge induced a decrease in the steady-state levels of these mRNAs. FSH induced an increase in I alpha mRNA concentrations in the regressed gonad, whereas both gonadotropins concomitantly down-regulated I beta B mRNA levels. In conclusion, the high expression of I alpha and I beta B mRNA in the regressed testis imply autocrine and paracrine roles for inhibin/activin in the quiescent gonad of seasonal breeders. Inhibin alpha-subunit expression is at least partly under the control of FSH in the bank vole testis.

  18. Behavioral and Biological Effects of Housing Conditions and Stress in Male Rats - Relevance to Heart Disease (United States)


    animals from different environments had different brain sizes. He reported that the brains of domestic rabbits were considerably smaller compared to the...brains of wild rabbits and argued that the reduced brain size of the domestic animals was a consequence of a deprived environment because...Briley, 1985), mice (Lister, 1987), guinea pigs ( Rex , Fink, & Marsden, 1994), and wild voles (Hendrie, Eilam, & Weiss, 1974). The EPM is

  19. Coxiella burnetii (Q-Fever) Seroprevalence in Prey and Predators in the United Kingdom: Evaluation of Infection in Wild Rodents, Foxes and Domestic Cats Using a Modified ELISA. (United States)

    Meredith, A L; Cleaveland, S C; Denwood, M J; Brown, J K; Shaw, D J


    Coxiella burnetii, the agent of Q-fever, is recognized as a worldwide zoonosis with a wide host range and potentially complex reservoir systems. Infected ruminants are the main source of infection for humans, but cats and other mammals, including wild rodents, also represent potential sources of infection. There has been a recent upsurge of reported cases in humans, domestic ruminants and wildlife in many parts of the world, and studies have indicated that wild brown rats may act as true reservoirs for C. burnetii and be implicated in outbreaks in livestock and humans. However, investigation of reservoir systems is limited by lack of validated serological tests for wildlife or other non-target species. In this study, serum samples from 796 wild rodents (180 bank voles, 309 field voles, 307 wood mice) 102 wild foxes and 26 domestic cats from three study areas in the UK were tested for the presence of antibodies to C. burnetii using a commercial indirect ELISA kit modified for use in multiple wildlife species. Test thresholds were determined for each species in the absence of species-specific reference sera using a bi-modal latent class mixture model to discriminate between positive from negative results. Based on the thresholds determined, seroprevalence in the wild rodents ranged from 15.6% to 19.1% depending on species (overall 17.3%) and was significantly higher in both foxes (41.2%) and cats (61.5%) than in rodents. This is the first report to quantify seroprevalence to C. burnetii in bank voles, field voles, wood mice, foxes and cats in the UK and provides evidence that predator species could act as indicators for the presence of C. burnetii in rodents. The study demonstrates that wildlife species could be significant reservoirs of infection for both livestock and humans, and the high seroprevalence in domestic cats highlights the potential zoonotic risk from this species.

  20. Development of a laboratory animal model for infectious bovine keratoconjunctivitis. (United States)

    Chandler, R L; Turfrey, B A; Smith, K


    Guinea pigs, gerbils, voles, golden hamsters and Chinese hamsters exposed to experimental infection with Moraxella bovis by ocular instillation or associated routes showed transient infections only and no clinical signs. Five strains of mice were of similarly low susceptibility but another, the C57 Bl strain, was relatively susceptible and treatment with corticosteroid before infection regularly produced keratoconjunctivitis. This system therefore offers a promising model for studies on infectious bovine keratoconjunctivitis.

  1. Radioactive cesium. Dynamics and transport in forestal food-webs; Radioaktivt cesium. Dynamik och transport i skogliga naeringsvaevar

    Energy Technology Data Exchange (ETDEWEB)

    Palo, T.; Nelin, P. [Swedish Univ. of Agricultural Sciences, Umeaa (Sweden). Dept. of Animal Ecology; Bergman, R.; Nylen, T. [FOA NBC Defence, Umeaa (Sweden)


    This report summarises results from a radioecological study during 1994-1995 concerning turnover, redistribution and loss of radioactive Cesium (134 and 137) in boreal forest ecosystems, as well as uptake and transfer in important food-chains over moose, vole and vegetation. The basis for this report are 9 publications published 1994-95. These reports are presented in summary form. 9 refs, 17 figs.

  2. La motivation: Un élément central dans la vie des associations sportives


    Cloes, Marc


    La motivation constitue un élément indispensable dans le succès sportif. Elle intervient au niveau de tous les acteurs de la vie sportive: athlètes, entraîneurs et bénévoles. Ce chapitre propose une présentation des principes généraux liés à la motivation et des illustrations de son implication en milieu sportif.

  3. Unique sex chromosome systems in Ellobius: How do male XX chromosomes recombine and undergo pachytene chromatin inactivation?


    Sergey Matveevsky; Irina Bakloushinskaya; Oxana Kolomiets


    Most mammalian species have heteromorphic sex chromosomes in males, except for a few enigmatic groups such as the mole voles Ellobius, which do not have the Y chromosome and Sry gene. The Ellobius (XX ♀♂ ) system of sex chromosomes has no analogues among other animals. The structure and meiotic behaviour of the two X chromosomes were investigated for males of the sibling species Ellobius talpinus and Ellobius tancrei. Their sex chromosomes, despite their identical G-structure, demonstrate sho...

  4. Habitat-specific impacts of multiple consumers on plant population dynamics. (United States)

    Maron, John L; Kauffman, Matthew J


    Multiple consumers often attack seeds, seedlings, and adult plants, but their population-level consequences remain uncertain. We examined how insect and small mammal consumers influenced the demography and abundance of the perennial shrub, bush lupine (Lupinus arboreus). In grassland and dune habitats we established replicate experimental lupine populations in 81-m2 plots that were either protected from, or exposed to, herbivorous voles and granivorous mice (via fencing) and/or root feeding insects (via insecticide treatment). Populations were initiated with transplanted seedlings in 1999 and 2000. We followed the demography of these cohorts, subsequent generations, and the seed bank for 5.5 years. Voles and insects killed many seedlings in dune (1999 only) and grassland (1999 and 2000) habitats. After 2000, insects and voles had minimal effects on seedling or adult survival. Seed predation by granivorous mice, however, greatly depressed seedling recruitment, resulting in lower adult lupine abundance in control plots vs. those protected from rodents. In grasslands, initial effects of voles and insects on seedling survival produced large differences among treatments in adult plant density and the cumulative number of seeds produced throughout the experiment. Differences among grassland populations in seed rain, however, had little influence on the magnitude of seedling recruitment into this habitat. Instead, recruitment out of a preexisting seed bank compensated for the lack of seed production in populations exposed to consumers. Shading by dense adults in plots protected from consumers limited seedling establishment within these populations. Although differences among populations in cumulative seed rain did not influence adult establishment, populations protected from consumers accumulated substantially larger seed banks than controls. These results illustrate how density dependence, habitat-specific seed dynamics, and particular demographic impacts of consumers

  5. Taxonomies of Organizational Change: Literature Review and Analysis (United States)


    iri1212111 1.,’lltoil I’.Pii--1k (1910) huns, ScIvdV~lL, rdI((h CA vole kir itY, cl1llo- re ( (I" I-! ti: l at) I 1011 rllo-je r , speneur IT ola 4...psychotherapy. Chicago, IL: Aldine," ]-96G. -191- • m . .m m • • Im orl" Van der Vall, M., Bolas , C., & Kang, T. S. Applied social research in industrial

  6. Yersinia spp. in Wild Rodents and Shrews in Finland. (United States)

    Joutsen, Suvi; Laukkanen-Ninios, Riikka; Henttonen, Heikki; Niemimaa, Jukka; Voutilainen, Liina; Kallio, Eva R; Helle, Heikki; Korkeala, Hannu; Fredriksson-Ahomaa, Maria


    Yersinia enterocolitica and Yersinia pseudotuberculosis are important zoonotic bacteria causing human enteric yersiniosis commonly reported in Europe. All Y. pseudotuberculosis strains are considered pathogenic, while Y. enterocolitica include both pathogenic and nonpathogenic strains which can be divided into six biotypes (1A, 1B, and 2-5) and about 30 serotypes. The most common types causing yersiniosis in Europe are Y. enterocolitica bioserotypes 4/O:3 and 2/O:9. Strains belonging to biotype 1A are considered as nonpathogenic because they are missing important virulence genes like the attachment-invasion-locus (ail) gene in the chromosome and the virulence plasmid. The role of wild small mammals as a reservoir of enteropathogenic Yersinia spp. is still obscure. In this study, the presence of Yersinia spp. was examined from 1840 wild small mammals, including voles, mice, and shrews, trapped in Finland during a 7-year period. We isolated seven Yersinia species. Y. enterocolitica was the most common species, isolated from 8% of the animals; while most of these isolates represented nonpathogenic biotype 1A, human pathogenic bioserotype 2/O:9 was also isolated from a field vole. Y. pseudotuberculosis of bioserotype 1/O:2 was isolated from two shrews. The ail gene, which is typically only found in the isolates of biotypes 1B and 2-5 associated with yersiniosis, was frequently (23%) detected in the nonpathogenic isolates of biotype 1A and sporadically (6%) in Yersinia kristensenii isolates. Our results suggest that wild small mammals, especially voles, may serve as carriers for ail-positive Y. enterocolitica 1A and Y. kristensenii. We also demonstrate that voles and shrews sporadically excrete pYV-positive Y. enterocolitica 2/O:9 and Y. pseudotuberculosis 1/O:2, respectively, in their feces and, thus, can serve as a contamination source for vegetables by contaminating the soil.

  7. Sex differences in spatial ability: a test of the range size hypothesis in the order Carnivora



    Sex differences in spatial cognition have been reported for many species ranging from voles to humans. The range size hypothesis predicts that sex differences in spatial ability will only occur in species in which the mating system selects for differential range size. Consistent with this prediction, we observed sex differences in spatial ability in giant pandas, a promiscuous species in which males inhabit larger ranges than females, but did not observe sex differences in Asian small-clawed ...

  8. A multiple lines of evidence approach for the ecological risk assessment of an accidental bitumen release from a steam assisted gravity drainage (SAGD) well in the Athabasca oil sands region. (United States)

    Berger, Robert G; Aslund, Melissa Whitfield; Sanders, Greg; Charlebois, Michael; Knopper, Loren D; Bresee, Karl E


    To assess the ecological impacts of two independent accidental bitumen releases from two steam assisted gravity drainage (SAGD) wells in the Athabasca oil sands region, a multiple lines of evidence (LOE) approach was developed. Following the release in 2010, action was taken to minimize environmental impact, including the selective removal of the most highly impacted vegetation and the use of oil socks to minimize possible runoff. An ecological risk assessment (ERA) was then conducted based on reported concentrations of bitumen related contaminants in soil, vegetation, and water. Results of biological assessments conducted at the site were also included in the risk characterization. Overall, the conclusion of the ERA was that the likelihood of long-term adverse health effects to ecological receptors in the area was negligible. To provide evidence for this conclusion, a small mammal sampling plan targeting Southern red-back voles (Myodes gapperi) was carried out at two sites and two relevant reference areas. Voles were readily collected at all locations and no statistically significant differences in morphometric measurements (i.e., body mass, length, foot length, and adjusted liver weight) were found between animals collected from impact zones of varying levels of coverage. Additionally, no trends corresponding with bitumen coverage were observed with respect to metal body burden in voles for metals that were previously identified in the source bitumen. Hepatic ethoxyresorufin-O-deethylase (EROD) activity was statistically significantly elevated in voles collected from the high impact zones of sites compared to those collected from the reference areas, a finding that is indicative of continued exposure to contaminants. However, this increase in EROD was not correlated with any observable adverse population-wide biological outcomes. Therefore the biological sampling program supported the conclusion of the initial ERA and supported the hypothesis of no significant

  9. Age, season and spatio-temporal factors affecting the prevalence of Echinococcus multilocularis and Taenia taeniaeformis in Arvicola terrestris

    Directory of Open Access Journals (Sweden)

    Deplazes Peter


    Full Text Available Abstract Background Taenia taeniaeformis and the related zoonotic cestode Echinococcus multilocularis both infect the water vole Arvicola terrestris. We investigated the effect of age, spatio-temporal and season-related factors on the prevalence of these parasites in their shared intermediate host. The absolute age of the voles was calculated based on their eye lens weights, and we included the mean day temperature and mean precipitation experienced by each individual as independent factors. Results Overall prevalences of E. multilocularis and T. taeniaeformis were 15.1% and 23.4%, respectively, in 856 A. terrestris trapped in the canton Zürich, Switzerland. Prevalences were lower in young (≤ 3 months: E. multilocularis 7.6%, T. taeniaeformis 17.9% than in older animals (>7 months: 32.6% and 34.8%. Only 12 of 129 E. multilocularis-infected voles harboured protoscoleces. Similar proportions of animals with several strobilocerci were found in T. taeniaeformis infected voles of E. multilocularis. In one trapping area, prevalences varied on an exceptional high level of 40.6-78.5% during the whole study period. Low temperatures significantly correlated with the infection rate whereas precipitation was of lower importance. Significant spatial variations in prevalences were also identified for Taenia taeniaeformis. Although the trapping period and the meteorological factors temperature and precipitation were included in the best models for explaining the infection risk, their effects were not significant for this parasite. Conclusions Our results demonstrate that, besides temporal and spatial factors, low temperatures contribute to the risk of infection with E. multilocularis. This suggests that the enhanced survival of E. multilocularis eggs under cold weather conditions determines the level of infection pressure on the intermediate hosts and possibly also the infection risk for human alveolar echincoccosis (AE. Therefore, interventions against the

  10. Deciphering bartonella diversity, recombination, and host specificity in a rodent community.

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    Jean-Philippe Buffet

    Full Text Available Host-specificity is an intrinsic feature of many bacterial pathogens, resulting from a long history of co-adaptation between bacteria and their hosts. Alpha-proteobacteria belonging to the genus Bartonella infect the erythrocytes of a wide range of mammal orders, including rodents. In this study, we performed genetic analysis of Bartonella colonizing a rodent community dominated by bank voles (Myodes glareolus and wood mice (Apodemus sylvaticus in a French suburban forest to evaluate their diversity, their capacity to recombine and their level of host specificity. Following the analysis of 550 rodents, we detected 63 distinct genotypes related to B. taylorii, B. grahamii, B. doshiae and a new B. rochalimae-like species. Investigating the most highly represented species, we showed that B. taylorii strain diversity was markedly higher than that of B. grahamii, suggesting a possible severe bottleneck for the latter species. The majority of recovered genotypes presented a strong association with either bank voles or wood mice, with the exception of three B. taylorii genotypes which had a broader host range. Despite the physical barriers created by host specificity, we observed lateral gene transfer between Bartonella genotypes associated with wood mice and Bartonella adapted to bank voles, suggesting that those genotypes might co-habit during their life cycle.

  11. Deciphering bartonella diversity, recombination, and host specificity in a rodent community. (United States)

    Buffet, Jean-Philippe; Pisanu, Benoît; Brisse, Sylvain; Roussel, Sophie; Félix, Benjamin; Halos, Lénaïg; Chapuis, Jean-Louis; Vayssier-Taussat, Muriel


    Host-specificity is an intrinsic feature of many bacterial pathogens, resulting from a long history of co-adaptation between bacteria and their hosts. Alpha-proteobacteria belonging to the genus Bartonella infect the erythrocytes of a wide range of mammal orders, including rodents. In this study, we performed genetic analysis of Bartonella colonizing a rodent community dominated by bank voles (Myodes glareolus) and wood mice (Apodemus sylvaticus) in a French suburban forest to evaluate their diversity, their capacity to recombine and their level of host specificity. Following the analysis of 550 rodents, we detected 63 distinct genotypes related to B. taylorii, B. grahamii, B. doshiae and a new B. rochalimae-like species. Investigating the most highly represented species, we showed that B. taylorii strain diversity was markedly higher than that of B. grahamii, suggesting a possible severe bottleneck for the latter species. The majority of recovered genotypes presented a strong association with either bank voles or wood mice, with the exception of three B. taylorii genotypes which had a broader host range. Despite the physical barriers created by host specificity, we observed lateral gene transfer between Bartonella genotypes associated with wood mice and Bartonella adapted to bank voles, suggesting that those genotypes might co-habit during their life cycle.

  12. Accelerated molecular evolution in Microtus (Rodentia) as assessed via complete mitochondrial genome sequences. (United States)

    Triant, Deborah A; Dewoody, J Andrew


    Microtus is one of the most taxonomically diverse mammalian genera, including over 60 extant species. These rodents have evolved rapidly, as the genus originated less than 2 million years ago. If these numbers are taken at face value, then an average of 30 microtine speciation events have occurred every million years. One explanation for the rapid rate of cladogenesis in Microtus could be the karyotypic differentiation exhibited across the genus: diploid numbers range from 17 to 64. Despite the striking chromosomal variability within Microtus, phenotypic variation is unremarkable. To determine whether nucleotide substitution rates are also elevated in voles, we sequenced the entire mitochondrial DNA (mtDNA) genome of the Eurasian sibling vole (Microtus rossiaemeridionalis). We compared this genome to another previously sequenced vole mtDNA genome (Microtus kikuchii) and performed pairwise sequence comparisons with the mtDNA genomes of ten additional mammalian genera. We found that microtine mtDNA genomes are evolving more rapidly than any other mammalian lineage we sampled, as gauged by the rate of nucleotide substitution across the entire mtDNA genome as well as at each individual protein-coding gene. Additionally, we compared substitution rates within the cytochrome b gene to seven other rodent genera and found that Microtus mtDNA is evolving fastest. The root cause of accelerated evolution in Microtus remains uncertain, but merits further investigation.

  13. Individual-Based Spatially-Explicit Model of an Herbivore and Its Resource: The Effect of Habitat Reduction and Fragmentation

    Energy Technology Data Exchange (ETDEWEB)

    Kostova, T; Carlsen, T; Kercher, J


    We present an individual-based, spatially-explicit model of the dynamics of a small mammal and its resource. The life histories of each individual animal are modeled separately. The individuals can have the status of residents or wanderers and belong to behaviorally differing groups of juveniles or adults and males or females. Their territory defending and monogamous behavior is taken into consideration. The resource, green vegetation, grows depending on seasonal climatic characteristics and is diminished due to the herbivore's grazing. Other specifics such as a varying personal energetic level due to feeding and starvation of the individuals, mating preferences, avoidance of competitors, dispersal of juveniles, as a result of site overgrazing, etc. are included in the model. We determined model parameters from real data for the species Microtus ochrogaster (prairie vole). The simulations are done for a case of an enclosed habitat without predators or other species competitors. The goal of the study is to find the relation between size of habitat and population persistence. The experiments with the model show the populations go extinct due to severe overgrazing, but that the length of population persistence depends on the area of the habitat as well as on the presence of fragmentation. Additionally, the total population size of the vole population obtained during the simulations exhibits yearly fluctuations as well as multi-yearly peaks of fluctuations. This dynamics is similar to the one observed in prairie vole field studies.

  14. Complete Genome and Phylogeny of Puumala Hantavirus Isolates Circulating in France (United States)

    Castel, Guillaume; Couteaudier, Mathilde; Sauvage, Frank; Pons, Jean-Baptiste; Murri, Séverine; Plyusnina, Angelina; Pontier, Dominique; Cosson, Jean-François; Plyusnin, Alexander; Marianneau, Philippe; Tordo, Noël


    Puumala virus (PUUV) is the agent of nephropathia epidemica (NE), a mild form of hemorrhagic fever with renal syndrome (HFRS) in Europe. NE incidence presents a high spatial variation throughout France, while the geographical distribution of the wild reservoir of PUUV, the bank vole, is rather continuous. A missing piece of the puzzle is the current distribution and the genetic variation of PUUV in France, which has been overlooked until now and remains poorly understood. During a population survey, from 2008 to 2011, bank voles were trapped in eight different forests of France located in areas known to be endemic for NE or in area from where no NE case has been reported until now. Bank voles were tested for immunoglobulin (Ig)G ELISA serology and two seropositive animals for each of three different areas (Ardennes, Jura and Orleans) were then subjected to laboratory analyses in order to sequence the whole S, M and L segments of PUUV. Phylogenetic analyses revealed that French PUUV isolates globally belong to the central European (CE) lineage although isolates from Ardennes are clearly distinct from those in Jura and Orleans, suggesting a different evolutionary history and origin of PUUV introduction in France. Sequence analyses revealed specific amino acid signatures along the N protein, including in PUUV from the Orleans region from where NE in humans has never been reported. The relevance of these mutations in term of pathophysiology is discussed. PMID:26506370

  15. Consumers limit the abundance and dynamics of a perennial shrub with a seed bank (United States)

    Kauffman, M.J.; Maron, J.L.


    For nearly 30 years, ecologists have argued that predators of seeds and seedlings seldom have population-level effects on plants with persistent seed banks and density-dependent seedling survival. We parameterized stage-based population models that incorporated density dependence and seed dormancy with data from a 5.5-year experiment that quantified how granivorous mice and herbivorous voles influence bush lupine (Lupinus arboreus) demography. We asked how seed dormancy and density-dependent seedling survival mediate the impacts of these consumers in dune and grassland habitats. In dune habitat, mice reduced analytical ?? (the intrinsic rate of population growth) by 39%, the equilibrium number of above-ground plants by 90%, and the seed bank by 98%; voles had minimal effects. In adjacent grasslands, mice had minimal effects, but seedling herbivory by voles reduced analytical ?? by 15% and reduced both the equilibrium number of aboveground plants and dormant seeds by 63%. A bootstrap analysis demonstrated that these consumer effects were robust to parameter uncertainty. Our results demonstrate that the quantitative strengths of seed dormancy and density-dependent seedling survival-not their mere existence-critically mediate consumer effects. This study suggests that plant population dynamics and distribution may be more strongly influenced by consumers of seeds and seedlings than is currently recognized. ?? 2006 by The University of Chicago.

  16. First report of Anaplasma phagocytophilum and Babesia microti in rodents in Finland. (United States)

    Kallio, Eva R; Begon, Michael; Birtles, Richard J; Bown, Kevin J; Koskela, Esa; Mappes, Tapio; Watts, Phillip C


    Tick-borne diseases pose an increasingly important public health problem in Europe. Rodents are the reservoir host for many tick-transmitted pathogens, including Anaplasma phagocytophilum and Babesia microti, which can cause human granulocytic anaplasmosis and babesiosis, respectively. To estimate the presence of these pathogens in rodents in Finland, we examined blood samples from 151 bank voles (Myodes glareolus) and demonstrate, for the first time, that A. phagocytophilum and B. microti commonly infect bank voles (in 22% and 40% of animals, respectively) in Finland. Sequence analysis of a fragment of 18S rRNA showed that the B. microti strain isolated was identical to the Munich strain, which is considered to be nonzoonotic. The A. phagocytophilum strain (based on a fragment of the msp4 gene) was identical to one found earlier in rodents in the United Kingdom that is transmitted by the tick Ixodes trianguliceps, all the life stages of which feed on small mammals. The infection probability of B. microti in the bank voles was the greater the older the individual was, and males were more often infected than females. A. phagocytophilum infection probability first increased and then decreased with the age of individual without any difference between sexes. While these pathogens presumably pose a limited zoonotic risk to humans in Finland, they might have important interactions with other rodent pathogens and therefore affect infection dynamics of, for example, zoonotic pathogens.

  17. Between-year variation and spatial dynamics of Cryptosporidium spp. and Giardia spp. infections in naturally infected rodent populations. (United States)

    Bajer, A


    Prevalence and abundance of Cryptosporidium spp. and Giardia spp. infections were studied over the 8-year period in 3 species of rodents in N.E. Poland (bank vole Myodes glareolus-1523; yellow-necked mouse Apodemus flavicollis- 638; common vole Microtus arvalis- 419). Prevalence was 53.8, 28.1 and 62.3% respectively for Cryptosporidium spp. and 58.3, 24.4 and 74.2% respectively for Giardia spp. Prevalence and abundance of infection varied markedly across 8 years of the study with 1998 and 2002 being years of higher prevalence and abundance, following changes in the densities of host species. The distribution of intestinal protozoa in forest rodents did not vary in the 3 isolated sites during the 4-year study. In the case of Cryptosporidium, fewer older animals carried infection and infections of the oldest bank and common voles were relatively milder. In the case of Giardia in yellow-necked mice, infections were more common in older age classes (2 and 3). The two species showed significant co-occurrence and in animals carrying both species there was a strong significant positive correlation between abundance of infection with each. These data are discussed in relation to the parasite genotypes identified in this region and in respect of the role of various ecological factors in shaping of intestinal protozoa communities.

  18. Experimental evolution on a wild mammal species results in modifications of gut microbial communities

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    Kevin eKohl


    Full Text Available Comparative studies have shown that diet, life history, and phylogeny interact to determine microbial community structure across mammalian hosts. However, these studies are often confounded by numerous factors. Selection experiments offer unique opportunities to validate conclusions and test hypotheses generated by comparative studies. We used a replicated, 15-generation selection experiment on bank voles (Myodes glareolus that have been selected for high swim-induced aerobic metabolism, predatory behavior towards crickets, and the ability to maintain body mass on a high-fiber, herbivorous diet. We predicted that selection on host performance, mimicking adaptive radiation, would result in distinct microbial signatures. We collected foregut and cecum samples from animals that were all fed the same nutrient-rich diet and had not been subjected to any performance tests. We conducted microbial inventories of gut contents by sequencing the V4 region of the 16S rRNA gene. We found no differences in cecal microbial community structure or diversity between control lines and the aerobic or predatory lines. However, the cecal chambers of voles selected for herbivorous capability harbored distinct microbial communities that exhibited higher diversity than control lines. The foregut communities of herbivorous-selected voles were also distinct from control lines. Overall, this experiment suggests that differences in microbial communities across herbivorous mammals may be evolved, and not solely driven by current diet or other transient factors.

  19. Phylogenetic relationships within Taenia taeniaeformis variants and other taeniid cestodes inferred from the nucleotide sequence of the cytochrome c oxidase subunit I gene. (United States)

    Okamoto, M; Bessho, Y; Kamiya, M; Kurosawa, T; Horii, T


    Nucleotide sequence variations in a region of the mitochondrial cytochrome c oxidase subunit I (COI) gene (391 bp) were examined within seven species of the genus Taenia and two species of the genus Echinococcus, including ten isolates of T. taeniaeformis and six isolates of E. multilocularis. More than a 12% rate of nucleotide differences between taeniid species was found, allowing the species to be distinguished. In E. multilocularis, no sequence variation was observed among isolates, regardless of the host (gray red-backed vole, tundra vole, pig, Norway rat) or area (Japan, Alaska) from which each metacestode had been isolated. In contrast, six distinct sequences were detected among the ten T. taeniaeformis isolates examined. The level of nucleotide variation in the COI gene within T. taeniaeformis isolates except for one isolate from the gray red-backed vole (TtACR), which has been proposed as a distinct strain or a different species, was about 0.3%-4.1%, whereas the COI gene sequence for TtACR differed from those of the other isolates, with levels being 9.0%-9.5%. Phylogenetic trees were then inferred from these sequence data using two different algorithms.

  20. Is the prevalence of Taenia taeniaeformis in Microtus arvalis dependent on population density? (United States)

    Fichet-Calvet, Elisabeth; Giraudoux, Patrick; Quéré, Jean-Pierre; Ashford, Richard William; Delattre, Pierre


    Populations of common voles Microtus arvalis were studied as hosts of the tapeworm Taenia taeniaeformis during a 14-yr survey. They were monitored in spring, summer, and autumn in a pastoral ecosystem in eastern France. A total of 7,574 voles were sampled during 2 multiannual population fluctuations. A third fluctuation was sampled during the increase phase only. Overall prevalence was lowest in summer (0.6%), increased by 3 times in autumn (1.5%) and a further 5 times in spring (7.8%). Analysis of prevalence, based on 7,384 voles, by multiple logistic regression revealed that extrinsic factors such as season and intrinsic factors such as host age and host density have a combined effect. In the longer term, host age and host density were positively associated with prevalence in summer. Host density was strongly associated with autumn prevalence. There was no association between the fluctuation phase and prevalence. The study shows that a long timescale (here a multiannual survey) is necessary to demonstrate the positive effect of host density on the prevalence of this indirectly transmitted parasite. The demonstration of this relationship depends on the rodents being intermediate rather than definitive hosts.

  1. A remote sensing tool to monitor and predict epidemiologic outbreaks of Hanta virus infections and Lyme disease (United States)

    Barrios, M.; Verstraeten, W. W.; Amipour, S.; Wambacq, J.; Aerts, J.-M.; Maes, P.; Berckmans, D.; Lagrou, K.; van Ranst, M.; Coppin, P.


    Lyme disease and Hanta virus infection are the result of the conjunction of several climatic and ecological conditions. Although both affections have different causal agents, they share an important characteristic which is the fact that rodents play an important role in the contagion. One of the most important agents in the dispersion of these diseases is the bank vole (Clethrionomys glareoulus). The bank vole is a common host for both, the Borrelia bacteria which via the ticks (Ixodes ricinus) reaches the human body and causes the Lyme disease, and the Nephropatia epidemica which is caused by Puumala Hantavirus and affects kidneys in humans. The prefered habitat of bank voles is broad-leaf forests with an important presence of beeches (Fagus sylvatica) and oaks (Quercus sp.) and a relatively dense low vegetation layer. These vegetation systems are common in West-Europe and their dynamics have a great influence in the bank voles population and, therefore, in the spreading of the infections this study is concerned about. The fact that the annual seed production is not stable in time has an important effect in bank voles population and, as it has been described in other studies, in the number of reported cases of Hanta virus infections and Lyme disease. The years in which an abundant production of seeds is observed are referred to as mast years which are believed to obey to cyclic patterns and to certain climatologically characteristics of the preceding years. Statistical analysis have confirmed the correlation in the behaviour of the number of infected cases and the presence of mast years. This project aims at the design of a remote sensing based system (INFOPRESS - INFectious disease Outbreak Prediction REmote Sensing based System) that should enable local and national health care instances to predict and locate the occurrence of infection outbreaks and design policies to counteract undesired effects. The predictive capabilities of the system are based on the

  2. Osteological histology of the Pan-Alcidae (Aves, Charadriiformes): correlates of wing-propelled diving and flightlessness. (United States)

    Smith, N Adam; Clarke, Julia A


    Although studies of osteological morphology, gross myology, myological histology, neuroanatomy, and wing-scaling have all documented anatomical modifications associated with wing-propelled diving, the osteohistological study of this highly derived method of locomotion has been limited to penguins. Herein we present the first osteohistological study of the derived forelimbs and hind limbs of wing-propelled diving Pan-Alcidae (Aves, Charadriiformes). In addition to detailing differences between wing-propelled diving charadriiforms and nondiving charadriiforms, microstructural modifications to the humeri, ulnae and femora of extinct flightless pan-alcids are contrasted with those of volant alcids. Histological thin-sections of four species of pan-alcids (Alca torda, †Alca grandis, †Pinguinus impennis, †Mancalla cedrosensis) and one outgroup charadriiform (Stercorarius longicaudus) were compared. The forelimb bones of wing-propelled diving charadriiforms were found to have significantly thicker (∼22%) cortical bone walls. Additionally, as in penguins, the forelimbs of flightless pan-alcids are found to be osteosclerotic. However, unlike the pattern documented in penguins that display thickened cortices in both forelimbs and hind limbs, the forelimb and hind limb elements of pan-alcids display contrasting microstructural morphologies with thickened forelimb cortices and relatively thinner femoral cortices. Additionally, the identification of medullary bone in the sampled †Pinguinus impennis specimen suggests that further osteohistological investigation could provide an answer to longstanding questions regarding sexual dimorphism of Great Auks. Finally, these results suggest that it is possible to discern volant from flightless wing-propelled divers from fragmentary fossil remains.

  3. Response of the dominant rodent species to close-to-nature logging practices in a temperate mixed forest

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    Peter Lešo


    Full Text Available The paper aims to answer the question whether differences exist in microhabitat preferences of the yellow-necked mouse and the bank vole between the natural forest and close-to-nature managed forest in the phase of stand regeneration. The two species were live-trapped during two periods in 2006 and 2007 on a square trapping grid established in a managed forest and a natural one. Ten microhabitat variables of each trapping point were measured to analyse their influence on the spatial distribution of the two species. At trapping points, the number of capture records for each species as a dependent variable was modelled using Generalised Linear Models. The herbal cover and a distance to the nearest woody debris were the most important measured microhabitat variables which affect the spatial distribution of both species. In the natural forest, the number of captures in both species increased significantly (p < 0.05 with a decreasing number of trees, increasing undergrowth coverage and decreasing distance to the nearest woody debris. In the managed forest, an increasing distance to the nearest tree and increasing herbal cover had a negative effect on the yellow-necked mouse occurrence (p < 0.001, while in contrast, the increase in values of the same variables increased frequency of occurrence of the bank vole (p < 0.001. Moreover, the bank vole was more frequent in the presence of woody debris (p < 0.002. The study demonstrated clearly that these species modify their spatial activity depending on the management of the woodland.

  4. Biological contribution to social influences on alcohol drinking: evidence from animal models. (United States)

    Anacker, Allison M J; Ryabinin, Andrey E


    Social factors have a tremendous influence on instances of heavy drinking and in turn impact public health. However, it is extremely difficult to assess whether this influence is only a cultural phenomenon or has biological underpinnings. Research in non-human primates demonstrates that the way individuals are brought up during early development affects their future predisposition for heavy drinking, and research in rats demonstrates that social isolation, crowding or low social ranking can lead to increased alcohol intake, while social defeat can decrease drinking. Neurotransmitter mechanisms contributing to these effects (i.e., serotonin, GABA, dopamine) have begun to be elucidated. However, these studies do not exclude the possibility that social effects on drinking occur through generalized stress responses to negative social environments. Alcohol intake can also be elevated in positive social situations, for example, in rats following an interaction with an intoxicated peer. Recent studies have also begun to adapt a new rodent species, the prairie vole, to study the role of social environment in alcohol drinking. Prairie voles demonstrate a high degree of social affiliation between individuals, and many of the neurochemical mechanisms involved in regulation of these social behaviors (for example, dopamine, central vasopressin and the corticotropin releasing factor system) are also known to be involved in regulation of alcohol intake. Naltrexone, an opioid receptor antagonist approved as a pharmacotherapy for alcoholic patients, has recently been shown to decrease both partner preference and alcohol preference in voles. These findings strongly suggest that mechanisms by which social factors influence drinking have biological roots, and can be studied using rapidly developing new animal models.

  5. An appraisal of the fitness consequences of forest disturbance for wildlife using habitat selection theory. (United States)

    Hodson, James; Fortin, Daniel; Leblanc, Mélanie-Louise; Bélanger, Louis


    Isodar theory can help to unveil the fitness consequences of habitat disturbance for wildlife through an evaluation of adaptive habitat selection using patterns of animal abundance in adjacent habitats. By incorporating measures of disturbance intensity or variations in resource availability into fitness-density functions, we can evaluate the functional form of isodars expected under different disturbance-fitness relationships. Using this framework, we investigated how a gradient of forest harvesting disturbance and differences in resource availability influenced habitat quality for snowshoe hares (Lepus americanus) and red-backed voles (Myodes gapperi) using pairs of logged and uncut boreal forest. Isodars for both species had positive intercepts, indicating reductions to maximum potential fitness in logged stands. Habitat selection by hares depended on both conspecific density and differences in canopy cover between harvested and uncut stands. Fitness-density curves for hares in logged stands were predicted to shift from diverging to converging with those in uncut forest across a gradient of high to low disturbance intensity. Selection for uncut forests thus became less pronounced with increasing population size at low levels of logging disturbance. Voles responded to differences in moss cover between habitats which reflected moisture availability. Lower moss cover in harvested stands either reduced maximum potential fitness or increased the relative rate of decline in fitness with density. Differences in vole densities between harvested and uncut stands were predicted, however, to diminish as populations increased. Our findings underscore the importance of accounting for density-dependent behaviors when evaluating how changing habitat conditions influence animal distribution.

  6. Perfluoroalkyl substance concentrations in a terrestrial raptor: relationships to environmental conditions and individual traits. (United States)

    Bustnes, Jan O; Bangjord, Georg; Ahrens, Lutz; Herzke, Dorte; Yoccoz, Nigel G


    Accumulation of persistent organic pollutants (POPs) in wildlife may be influenced by the physical and biotic environment, and concentrations vary greatly among areas, seasons, and individuals. Different hypotheses about sources of variation in perfluoroalkyl substance (PFAS) concentrations were examined in eggs (n = 107) of tawny owls (Strix aluco) collected over a 24-yr period (1986-2009) in Norway. Predictor variables included the North Atlantic Oscillation (NAO), temperature, snow, food availability (vole abundance), and individual traits such as age, body condition, and clutch size. Concentrations of both perfluoro-octane sulfonate (PFOS) and perfluoroalkyl carboxylates (PFCAs) varied several fold in the population, both inter- and intra-annually. Moreover, individuals laid eggs with several times higher or lower PFAS concentrations within few years (1 yr-5 yr). After controlling for temporal trends (i.e., declining PFOS and increasing PFCA concentrations), both PFOS and PFCAs were positively associated to the winter NAO in the previous year (NAOy - 1 ), suggesting that atmospheric transport may be affecting the input of PFASs to the local ecosystem. Perfluoro-octane sulfonate was negatively related to temperature, but the pattern was complex as there was an interaction between temperature and the feeding conditions. The PFOS accumulation was highest in years with high vole abundance and low to medium temperatures. For PFCAs, there was an interaction between NAOy - 1 and feeding conditions, suggesting that strong air transport toward Norway and high consumption of voles led to a moderate increase in PFCA accumulation. The individual traits, however, had very little impact on the concentrations of PFASs in the eggs. The present study thus suggests that annual variation in environmental conditions influences the concentrations of PFASs in a terrestrial raptor such as the tawny owl.

  7. Natal conditions alter age-specific reproduction but not survival or senescence in a long-lived bird of prey. (United States)

    Millon, Alexandre; Petty, Steve J; Little, Brian; Lambin, Xavier


    1. Natal conditions and senescence are two major factors shaping life-history traits of wild animals. However, such factors have rarely been investigated together, and it remains largely unknown whether they interact to affect age-specific performance. 2. We used 27 years of longitudinal data collected on tawny owls with estimates of prey density (field voles) from Kielder Forest (UK) to investigate how prey density at birth affects ageing patterns in reproduction and survival. 3. Natal conditions experienced by tawny owls, measured in terms of vole density, dramatically varied among cohorts and explained 87% of the deviance in first-year apparent survival (annual estimates ranging from 0·07 to 0·33). 4. We found evidence for senescence in survival for females as well as for males. Model-averaged estimates showed that adult survival probability declined linearly with age for females from age 1. In contrast, male survival probability, lower on average than for female, declined after a plateau at age 1-3. 5. We also found evidence for reproductive senescence (number of offspring). For females, reproductive performance increased until age 9 then declined. Males showed an earlier decline in reproductive performance with an onset of senescence at age 3. 6. Long-lasting effects of natal environmental conditions were sex specific. Female reproductive performance was substantially related to natal conditions (difference of 0·24 fledgling per breeding event between females born in the first or third quartile of vole density), whereas male performance was not. We found no evidence for tawny owls born in years with low prey density having accelerated rates of senescence. 7. Our results, combined with previous findings, suggest the way natal environmental conditions affect senescence varies not only across species but also within species according to gender and the demographic trait considered.

  8. Response of the dominant rodent species to close-to-nature logging practices in a temperate mixed forest

    Directory of Open Access Journals (Sweden)

    Peter Lešo


    Full Text Available The paper aims to answer the question whether differences exist in microhabitat preferences of the yellow-necked mouse and the bank vole between the natural forest and close-to-nature managed forest in the phase of stand regeneration. The two species were live-trapped during two periods in 2006 and 2007 on a square trapping grid established in a managed forest and a natural one. Ten microhabitat variables of each trapping point were measured to analyse their influence on the spatial distribution of the two species. At trapping points, the number of capture records for each species as a dependent variable was modelled using Generalised Linear Models. The herbal cover and a distance to the nearest woody debris were the most important measured microhabitat variables which affect the spatial distribution of both species. In the natural forest, the number of captures in both species increased significantly (p < 0.05 with a decreasing number of trees, increasing undergrowth coverage and decreasing distance to the nearest woody debris. In the managed forest, an increasing distance to the nearest tree and increasing herbal cover had a negative effect on the yellow-necked mouse occurrence (p < 0.001, while in contrast, the increase in values of the same variables increased frequency of occurrence of the bank vole (p < 0.001. Moreover, the bank vole was more frequent in the presence of woody debris (p < 0.002. The study demonstrated clearly that these species modify their spatial activity depending on the management of the woodland.

  9. Inclusion of soil arsenic bioaccessibility in ecological risk assessment and comparison with biological effects. (United States)

    Saunders, Jared R; Knopper, Loren D; Koch, Iris; Reimer, Kenneth J


    The purpose of this study was to conduct an ecological risk assessment (ERA) for meadow voles (Microtus pennslvanicus) found at three arsenic contaminated sites in Nova Scotia, Canada (as well as two background locations) and to compare the numeric results to measured biomarkers of exposure and effect. The daily intake of arsenic by meadow voles was determined by three separate calculations: estimated daily intake (EDI), bioaccessible estimated daily intake (BEDI, with bioaccessibility of soil included), and actual daily intake (ADI, which is calculated with arsenic concentrations in the stomach contents). The median bioaccessibility of arsenic in soils from the contaminated locations was significantly greater than at background locations. The bioaccessible arsenic concentration in soil from all samples (both contaminated and background) was significantly less than the total concentration. Use of site-specific bioaccessibility (hazard quotients=38 at Upper Seal Harbour (USH); 60 at Lower Seal Harbour (LSH); and 120 at Montague tailings (MONT)) and stomach arsenic contents (hazard quotients=2.1 at USH; 7.9 at LSH; and 6.7 at MONT) in the ERA resulted in lower numeric risk than compared to risk calculated with 100% bioavailability (hazard quotient=180 at USH; 75 at LSH; and 680 at MONT). Further, the use of bioaccessibility on the calculation of risk was aligned with biomarker results (changes in glutathione and micronucleated erythrocytes) in voles captured at the sites. This study provides evidence that using site-specific bioaccessibility in ERAs may provide a more realistic level of conservatism, thereby enhancing the accuracy of predicting risk to wildlife receptors. Furthermore, when numeric risk assessments are combined with site-specific biological data (i.e., biomarkers of exposure and effect), both lines of evidence can be used to make informed decisions about ecological risk and site management. Copyright © 2011. Published by Elsevier B.V.

  10. Strong "bottom-up" influences on small mammal populations: State-space model analyses from long-term studies. (United States)

    Flowerdew, John R; Amano, Tatsuya; Sutherland, William J


    "Bottom-up" influences, that is, masting, plus population density and climate, commonly influence woodland rodent demography. However, "top-down" influences (predation) also intervene. Here, we assess the impacts of masting, climate, and density on rodent populations placed in the context of what is known about "top-down" influences. To explain between-year variations in bank vole Myodes glareolus and wood mouse Apodemus sylvaticus population demography, we applied a state-space model to 33 years of catch-mark-release live-trapping, winter temperature, and precise mast-collection data. Experimental mast additions aided interpretation. Rodent numbers in European ash Fraxinus excelsior woodland were estimated (May/June, November/December). December-March mean minimum daily temperature represented winter severity. Total marked adult mice/voles (and juveniles in May/June) provided density indices validated against a model-generated population estimate; this allowed estimation of the structure of a time-series model and the demographic impacts of the climatic/biological variables. During two winters of insignificant fruit-fall, 6.79 g/m(2) sterilized ash seed (as fruit) was distributed over an equivalent woodland similarly live-trapped. September-March fruit-fall strongly increased bank vole spring reproductive rate and winter and summer population growth rates; colder winters weakly reduced winter population growth. September-March fruit-fall and warmer winters marginally increased wood mouse spring reproductive rate and September-December fruit-fall weakly elevated summer population growth. Density dependence significantly reduced both species' population growth. Fruit-fall impacts on demography still appeared after a year. Experimental ash fruit addition confirmed its positive influence on bank vole winter population growth with probable moderation by colder temperatures. The models show the strong impact of masting as a "bottom-up" influence on rodent demography

  11. An Animal Model for Collective Behavior in Humans: The Impact of Manipulated Trust and Aggression (United States)


    agricultural and urban environments (Charter et al. 2007, 2009). Thirty-eight male and 25 female voles were obtained from breeding colonies at the I. Meier...predation risk. Anim Behav 77:101–107 Charter M, Izhaki I, Shapira L, Leshem Y (2007) Diets of urban breeding barn owls (Tyto alba) in Tel Aviv, Israel...obtained from chicken -hatcheries. We used live owls since our previous studies with models or owl calls as threat had revealed that these stimuli are not

  12. [Natural focus of tularemia on the Kerchen peninsula (Crimea)]. (United States)

    Golkovskiĭ, G M; Mitsevich, G F; Khaĭtovich, A B; Alekseev, E V; Korchevskiĭ, P G


    The study confirming the existence of the steppe-type natural focus of tularemia on the Kerch peninsula has been carried out. For the first time the cultures of Francisella tularensis have been isolated. Voles and house mice play the main role in the circulation of the infection. The parasitic system comprises ticks (Ixodidae and Nyalomma), as well as some species of fleas. In carrying out erizootological studies for detecting tularemia in the Crimea the use of low temperature (0 degrees C) for the preservation of specimens and preparations in recommended.

  13. Interagency Symposium on University Research in Transportation Noise (2nd) Held at North Carolina State Univ., Raleigh on June 5-7, 1974. Book of Proceedings, Volume I (United States)


    DIRECTIONAL PATTERN OF BLONN FLAP NOISE AT lf/D-3.75. x/o-5.75, Y/D-2.0 DIFFERENT FLAP LENGTH. H-.W, X/D-5.75, Y/D-2.0. »•• 0 dB FIB . 5A OVERALL...Coward, U.E., Hoshheiser, R.M., Kazin, S.B. and Knott , P.R., "Fan/Compressor Noise Research," Rept« No. FAA-RD-71-85. Vole. I,Il,III,Ma7

  14. Effect of landscape features on the relationship between Ixodes ricinus ticks and their small mammal hosts. (United States)

    Perez, Grégoire; Bastian, Suzanne; Agoulon, Albert; Bouju, Agnès; Durand, Axelle; Faille, Frédéric; Lebert, Isabelle; Rantier, Yann; Plantard, Olivier; Butet, Alain


    The consequences of land use changes are among the most cited causes of emerging infectious diseases because they can modify the ecology and transmission of pathogens. This is particularly true for vector-borne diseases which depend on abiotic (e.g. climate) and biotic conditions (i.e. hosts and vectors). In this study, we investigated how landscape features affect the abundances of small mammals and Ixodes ricinus ticks, and how they influence their relationship. From 2012 to 2014, small mammals and questing I. ricinus ticks were sampled in spring and autumn in 24 sites located in agricultural and forest landscapes in Brittany, France. We tested the effects of landscape features (composition and configuration) on the abundances of small mammal species and immature ticks and their relationship. Additionally, we quantified the larval tick burden of small mammals in 2012 to better describe this relationship. The nymph abundance was positively influenced by the larval occurrence and the wood mouse Apodemus sylvaticus abundance the previous spring because they hosted tenfold more larvae than the bank vole Myodes glareolus. The bank vole abundance in spring and autumn had a negative and positive effect, respectively, on the nymph abundance. In agricultural landscapes, wood mice were positively influenced by woodland cover and woodland/hedgerow-grassland ecotone, whereas bank voles showed the opposite or non-significant responses to these landscape variables. The woodland cover had a positive effect on immature ticks. The landscape configuration, likely by affecting the landscape connectivity, influences the small mammal communities in permanent habitats. Our study showed that the wood mouse, due to its dominance and to its tolerance to ticks, feeds a substantial proportion of larvae. The acquired resistance to ticks in the bank vole can reduce its role as a trophic resource over time. The nymph abundance seems indirectly influenced by landscape features via their

  15. Factors Affecting Growth of Tengmalm's Owl (Aegolius funereus) Nestlings: Prey Abundance, Sex and Hatching Order. (United States)

    Zárybnická, Markéta; Riegert, Jan; Brejšková, Lucie; Šindelář, Jiří; Kouba, Marek; Hanel, Jan; Popelková, Alena; Menclová, Petra; Tomášek, Václav; Šťastný, Karel


    In altricial birds, energy supply during growth is a major predictor of the physical condition and survival prospects of fledglings. A number of experimental studies have shown that nestling body mass and wing length can vary with particular extrinsic factors, but between-year observational data on this topic are scarce. Based on a seven-year observational study in a central European Tengmalm's owl population we examine the effect of year, brood size, hatching order, and sex on nestling body mass and wing length, as well as the effect of prey abundance on parameters of growth curve. We found that nestling body mass varied among years, and parameters of growth curve, i.e. growth rate and inflection point in particular, increased with increasing abundance of the owl's main prey (Apodemus mice, Microtus voles), and pooled prey abundance (Apodemus mice, Microtus voles, and Sorex shrews). Furthermore, nestling body mass varied with hatching order and between sexes being larger for females and for the first-hatched brood mates. Brood size had no effect on nestling body mass. Simultaneously, we found no effect of year, brood size, hatching order, or sex on the wing length of nestlings. Our findings suggest that in this temperate owl population, nestling body mass is more sensitive to prey abundance than is wing length. The latter is probably more limited by the physiology of the species.

  16. Thyroid function and reproductive success in rodents exposed to perchlorate via food and water. (United States)

    Smith, Philip N; Severt, Scott A; Jackson, J W Andrew; Anderson, Todd A


    The purpose of the present study was to determine if exposure to perchlorate via food items would have effects on mammals similar to those caused by exposure through drinking water at approximately equivalent doses. Prairie voles (Microtus ochrogaster) and deer mice (Peromyscus maniculatus) were used to assess the potential toxicity of perchlorate-contaminated food items. Voles and mice were divided randomly into three treatment groups--perchlorate-contaminated food (PCF), perchlorate-contaminated water (PCW), and control groups--such that each treatment group contained equal numbers of males and females. Rodents in PCF treatment groups were fed chow formulated with soybean plant matter that had been grown with perchlorate-contaminated irrigation water. Individuals in the control and PCF groups were provided distilled/deionized drinking water, whereas the PCW group received drinking water containing sodium perchlorate. Only slight differences among treatment groups were observed in a variety of endpoints, including reproductive success, tissue perchlorate concentrations, thyroid hormone concentrations, and thyroid histology. However, trends observed in the present study suggest that perchlorate exposure via water may result in slightly greater effects than exposure to perchlorate via food. These data and recent reports of perchlorate in a wide variety of food items indicate that exposure via food intake is an important consideration when examining cumulative risk among humans, livestock, and wildlife.

  17. Oxytocin and Social Relationships: From Attachment to Bond Disruption. (United States)

    Bosch, Oliver J; Young, Larry J


    Social relationships throughout life are vital for well-being and physical and mental health. A significant amount of research in animal models as well as in humans suggests that oxytocin (OT) plays an important role in the development of the capacity to form social bonds, the mediation of the positive aspects of early-life nurturing on adult bonding capacity, and the maintenance of social bonding. Here, we focus on the extensive research on a socially monogamous rodent model organism, the prairie vole (Microtus ochrogaster). OT facilitates mating-induced pair bonds in adults through interaction with the mesolimbic dopamine system. Variation in striatal OT receptor density predicts resilience and susceptibility to neonatal social neglect in female prairie voles. Finally, in adults, loss of a partner results in multiple disruptions in OT signaling, including decreased OT release in the striatum, which is caused by an activation of the brain corticotropin releasing factor (CRF) system. The dramatic behavioral consequence of partner loss is increased depressive-like behavior reminiscent of bereavement. Importantly, infusions of OT into the striatum of adults prevents the onset of depressive-like behavior following partner loss, and evoking endogenous OT release using melanocortin agonists during neonatal social isolation rescues impairments in social bonding in adulthood. This work has important translational implications relevant to the disruptions of social bonds in childhood and in adults.

  18. Seroprevalence of Encephalitozoon cuniculi in wild rodents, foxes and domestic cats in three sites in the United Kingdom. (United States)

    Meredith, A L; Cleaveland, S C; Brown, J; Mahajan, A; Shaw, D J


    Encephalitozoon cuniculi is an obligate intracellular microsporidian that is the causal agent of encephalitozoonosis, an important and emerging disease in both humans and animals. Little is known about its occurrence in wildlife. In this study, serum samples from 793 wild rodents [178 bank voles (BV), 312 field voles (FV) and 303 wood mice (WM)], 96 foxes and 27 domestic cats from three study areas in the UK were tested for the presence of antibodies to E. cuniculi using a direct agglutination test (DAT). Seroprevalence in the wild rodents ranged from 1.00% to 10.67% depending on species (overall 5.31%) and was significantly higher in foxes [49.50% (50/96)]. None of the 27 cats sampled were found to be seropositive. This is the first report of seroprevalence to E. cuniculi in BV, FV, WM, foxes and cats in the UK and provides some evidence that foxes could act as sentinels for the presence of E. cuniculi in rodents. The study demonstrates that wildlife species could be significant reservoirs of infection for both domestic animals and humans.

  19. Hazards of Secondary Bromadiolone Intoxications Evaluated using High-performance Liquid Chromatography with Electrochemical Detection

    Directory of Open Access Journals (Sweden)

    René Kizek


    Full Text Available This study reported on the possibility of intoxications of non-target wild animalsassociated with use of bromadiolone as the active component of rodenticides withanticoagulation effects. A laboratory test was done with earthworms were exposed tobromadiolone-containing granules under the conditions specified in the modified OECD207 guideline. No mortality of earthworms was observed during the fourteen days longexposure. When the earthworms from the above test became a part of the diet of commonvoles in the following experiment, no mortality of consumers was observed too. However,electrochemical analysis revealed higher levels of bromadiolone in tissues fromearthworms as well as common voles compared to control animals. There were determinedcomparable levels of bromadiolone in the liver tissue of common voles after primary(2.34±0.10 μg/g and secondary (2.20±0.53 μg/g intoxication. Therefore, the risk ofsecondary intoxication of small mammalian species feeding on bromadiolone-containing earthworms is the same as of primary intoxication through baited granules. Bromadiolone bio-accumulation in the food chain was monitored using the newly developed analytical procedure based on the use of a liquid chromatography coupled with electrochemical detector (HPLC-ED. The HPLC-ED method allowed to determine the levels of bromadiolone in biological samples and is therefore suitable for examining the environmental hazards of this substance.


    Ushakov, A V


    A cyclic change in the epizootic activity of a tularemia activity underlies the mechanism of natural opisthorchiasis focus pulsation in the combined focus of opisthorchiasis and tularemia in the ecosystem of the Konda River. This is due to mass breeding and depression in the water vole (Arvicola terrestris) population. The mass breeding is predetermined by high population reproduction constants. The rodents' potential fecundity occurs with the high capacity of lands, which is caused by the hydrological regime of rivers. The size depression is predetermined by the epizootics of tularemia. The water vole is a host of the pathogens of opisthorchiasis and tularemia. So the mass rodent breeding in the combined infection and invasion focus causes an increase in the number of real invasion sources. The epizootic of tularemia is responsible for elimination of these invasion sources and for decreases in the flow of invasion material, the infection rate of Codiella and hence the amount of their produced cercarae, the extensive and intensive indicators of fish contamination, and the intensity of an epizootic process in the opisthorchiasis focus.

  1. Lemming winter habitat choice: a snow-fencing experiment. (United States)

    Reid, Donald G; Bilodeau, Frédéric; Krebs, Charles J; Gauthier, Gilles; Kenney, Alice J; Gilbert, B Scott; Leung, Maria C-Y; Duchesne, David; Hofer, Elizabeth


    The insulative value of early and deep winter snow is thought to enhance winter reproduction and survival by arctic lemmings (Lemmus and Dicrostonyx spp). This leads to the general hypothesis that landscapes with persistently low lemming population densities, or low amplitude population fluctuations, have a low proportion of the land base with deep snow. We experimentally tested a component of this hypothesis, that snow depth influences habitat choice, at three Canadian Arctic sites: Bylot Island, Nunavut; Herschel Island, Yukon; Komakuk Beach, Yukon. We used snow fencing to enhance snow depth on 9-ha tundra habitats, and measured the intensity of winter use of these and control areas by counting rodent winter nests in spring. At all three sites, the density of winter nests increased in treated areas compared to control areas after the treatment, and remained higher on treated areas during the treatment. The treatment was relaxed at one site, and winter nest density returned to pre-treatment levels. The rodents' proportional use of treated areas compared to adjacent control areas increased and remained higher during the treatment. At two of three sites, lemmings and voles showed significant attraction to the areas of deepest snow accumulation closest to the fences. The strength of the treatment effect appeared to depend on how quickly the ground level temperature regime became stable in autumn, coincident with snow depths near the hiemal threshold. Our results provide strong support for the hypothesis that snow depth is a primary determinant of winter habitat choice by tundra lemmings and voles.

  2. Landscape-related variation in the diet composition of the common buzzard (Buteo buteo in Belarus

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    Sidorovich Anna A.


    Full Text Available We examined common buzzard (Buteo buteo feeding patterns in landscapes with different habitat structure in Belarus. A total of 561 pellets and prey remains were sampled in 1998-2012 from which 1065 prey and other food items were identified. Effects of habitat structure on buzzard diet composition were investigated using correlation analysis. The most abundant group in buzzards’ diets were small rodents (49-80% of the biomass consumed, followed by other mammals and birds. Reptiles, anurans, fish and invertebrates constituted the rest. Proportions of all food items varied greatly between landscapes. The mean-weighted body mass of vertebrate prey hunted by common buzzards in different landscapes ranged from 107 to 244 g, constituting on average 180 g. Among small rodents, voles of the genus Microtus were hunted selectively. The food niche breadth was directly proportional to the amount of forest habitat. With increasing amount of forest habitat, the proportion of Microtus voles in buzzards’ diets decreased and the proportions of other food items grew. These findings confirm the majority of previous results indicating feeding opportunism of the common buzzard. Our investigation enables better understanding of predator-prey interactions and the prey choice of the common buzzard in Belarus.

  3. Numerical Response of the Common Buzzard Buteo Buteo to The Changes In Abundance Of Small Mammals

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    Tóth László


    Full Text Available I investigated the numerical response of the Common Buzzard to variations in density of small mammals. The study was carried out at the Hortobágy region in 2000-2001. During nest visiting periods clutch size, number of hatched and fledged young were recorded. Population of small mammals were also monitored by live-trapping. Effect of weather on the survival of overwintering rodents was also investigated. There was significant difference in clutch size between 2000 and 2001 (means 2.3 and 3.1. It can be explained by the remarkable differences in abundance of small mammal populations between the two years. The density of rodents was very low (9 specimen/ha in 2000. During 2001 the amount of small mammals has increased more than eightfold (76 specimen/ha. In February and March, 2000 there were 4 short mild periods alternating with 4 freezing periods, when distribution of significant precipitation (6-8 mm rainfall in each coincided with the mild periods. Thus the overwintering population almost extincted from the area because the tunnel complexes of voles are repeatedly flooded and huge part of the animals died, resulting very low density during the breeding season. In 2001 there was no such alternating periods, mild weather started 3 weeks earlier, thus voles overwintered successfully and their numbers increased rapidly producing a peak during the breeding season.

  4. Unique sex chromosome systems in Ellobius: How do male XX chromosomes recombine and undergo pachytene chromatin inactivation? (United States)

    Matveevsky, Sergey; Bakloushinskaya, Irina; Kolomiets, Oxana


    Most mammalian species have heteromorphic sex chromosomes in males, except for a few enigmatic groups such as the mole voles Ellobius, which do not have the Y chromosome and Sry gene. The Ellobius (XX ♀♂) system of sex chromosomes has no analogues among other animals. The structure and meiotic behaviour of the two X chromosomes were investigated for males of the sibling species Ellobius talpinus and Ellobius tancrei. Their sex chromosomes, despite their identical G-structure, demonstrate short synaptic fragments and crossover-associated MLH1 foci in both telomeric regions only. The chromatin undergoes modifications in the meiotic sex chromosomes. SUMO-1 marks a small nucleolus-like body of the meiotic XX. ATR and ubiH2A are localized in the asynaptic area and the histone γH2AFX covers the entire XX bivalent. The distribution of some markers of chromatin inactivation differentiates sex chromosomes of mole voles from those of other mammals. Sex chromosomes of both studied species have identical recombination and meiotic inactivation patterns. In Ellobius, similar chromosome morphology masks the functional heteromorphism of the male sex chromosomes, which can be seen at meiosis.

  5. Influence of parasitism on the use of small terrestrial rodents in environmental pollution monitoring

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    Jankovska, Ivana, E-mail: jankovska@af.czu.c [Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic); Miholova, Daniela [Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic); Langrova, Iva [Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic); Bejcek, Vladimir [Department of Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic); Vadlejch, Jaroslav [Department of Zoology and Fisheries, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic); Kolihova, Dana; Sulc, Miloslav [Department of Chemistry, Faculty of Agrobiology, Food and Natural Resources, Czech University of Life Sciences, Kamycka 129, 165 21 Prague 6 - Suchdol (Czech Republic)


    Bioaccumulation of cadmium, chromium, copper, manganese, nickel, lead and zinc in small terrestrial rodents - voles and their cestode parasite Paranoplocephala dentata was studied. Contents of Pb, Mn, Ni and Zn in the parasite were found to be higher than in the kidney and liver of the parasitized animals. Lead level in the cestode was 37 fold higher than in the liver of the infected rodents. Bioaccumulation factors of zinc, nickel and manganese in the cestode are mostly in the range from 2 to 4.5. Considering the different contents of manganese and zinc in livers of non-parasitized and parasitized rodents, kidney tissue was found to be more reliable than liver as an indicator of environmental pollution by manganese and zinc; the kidneys of parasitized animals showed no significant change in the concentrations of those elements that are accumulated in the cestode. - Liver tissue from voles infected by Paranoplocephala dentata was less suitable as a biomonitor for metal contamination than kidney tissue.

  6. [The ecology of Cryptosporidium parvum infection in small rodent populations]. (United States)

    Bajer, A; Bednarska, M; Siński, E


    The prevalence and abundance of Cryptosporidium parvum were studied over a three year period (1997-1999) in three species of rodents sampled from forest and abandoned fields in the Mazury Lake District, Poland. The overall prevalence was consistently higher in voles compared with Apodemus flavicollis (70.6% in Clethrionomys glareolus, 73.0% in Microtus arvalis and 27.8% in A. flavicollis). The prevalence and abundance of infection also varied across the 3 years of the study with 1998 being the year of higher prevalence and abundance of the parasite. Fewer older animals carried the infection, and their infections were relatively mild. We found no consistent pattern of seasonal changes despite the significance of seasonal differences. Host sex did not influence either the prevalence or abundance of infection with C. parvum. A great proportion of recaptured voles developed chronic infections between consecutive trapping sessions and only a small number of animals recovered. However, yellow-necked mice seem to be much more resistant to infection that became self-limiting. Our results firmly establish that the common woodland and grassland wild rodents in the Mazury Lake District constitute a significant and hazardous reservoir of C. parvum for animals and humans.

  7. Prevalence and abundance of Cryptosporidium parvum and giardia spp. in wild rural rodents from the Mazury Lake District region of Poland. (United States)

    Bajer, A; Bednarska, M; Pawełczyk, A; Behnke, J M; Gilbert, F S; Sinski, E


    Prevalence and abundance of Cryptosporodium parvum and Giardia spp. were studied in 3 species of rodents from forests and abandoned agricultural fields in N.E. Poland (Clethrionomys glareolus n = 459; Microtus arvalis n = 274; Apodemus flavicollis n = 209). Overall prevalence was consistently higher in the voles compared with A. flavicollis (70.6, 73.0 and 27.8% respectively for C. parvum and 93.9, 96.3 and 48.3% respectively for Giardia spp.). Prevalence and abundance of infection also varied markedly across 3 years with 1998 being a year of higher prevalence and abundance with both species. Fewer older animals (especially C. glareolus and M. arvalis) carried infection with C. parvum and infections in these animals were relatively milder. Although seasonal differences were significant, no consistent pattern of changes was apparent. Host sex did not influence prevalence or abundance of infection with C. parvum, but made a small contribution to a 4-way interaction (in 5-way ANOVA) with other factors in the case of Giardia spp. The 2 species co-occurred significantly and in animals carrying both parasites there was a highly significant positive correlation between abundance of infection with each, even with between-year, seasonal, host age, sex and species differences taken into account. Quantitative associations were confined to the 2 vole species in the study. These results are discussed in relation to the importance of wild rodents as reservoir hosts and sources of infection for local human communities.

  8. Biased sex ratio among worms of the family Heligmosomidae--searching for a mechanism. (United States)

    Kloch, Agnieszka; Michalski, Aleksander; Bajer, Anna; Behnke, Jerzy


    According to Fisher's principle, an equal sex ratio is an evolutionary stable strategy. However, biased sex ratios have been reported in many metazoan parasite species, although the causes and mechanisms of the observed bias are still poorly understood. In the present study, we analysed sex ratios in long-term datasets from three populations of bank voles (Clethrionomys (=Myodes) glareolus) infected with Heligmosomum mixtum and Heligmosomoides glareoli. The overall sex ratios of both species were female-biased but in contrast to previous studies we did not find a relationship between the proportion of females and infection intensity. A higher female bias was observed in older hosts, suggesting that the sex ratio changes over time; the lifespan of nematodes in the family Heligmosomidae is known to be comparable with that of their hosts. We also compared the distributions of sexes in voles infected with two, three, four or five worms and we found significant differences from the expected values in both parasite species. In infections with four and five H. glareoli we observed more single-sex infections than expected, both female- and male-dominated, whereas in the case of H. mixtum female-dominated infections were more frequent.

  9. Neonatal monosodium glutamate treatment counteracts circadian arrhythmicity induced by phase shifts of the light-dark cycle in female and male Siberian hamsters. (United States)

    Prendergast, Brian J; Onishi, Kenneth G; Zucker, Irving


    Studies of rats and voles suggest that distinct pathways emanating from the anterior hypothalamic-retrochiasmatic area and the mediobasal hypothalamic arcuate nucleus independently generate ultradian rhythms (URs) in hormone secretion and behavior. We evaluated the hypothesis that destruction of arcuate nucleus (ARC) neurons, in concert with dampening of suprachiasmatic nucleus (SCN) circadian rhythmicity, would compromize the generation of ultradian rhythms (URs) of locomotor activity. Siberian hamsters retain-->of both sexes treated neonatally with monosodium glutamate (MSG) that destroys ARC neurons were subjected in adulthood to a circadian disrupting phase-shift protocol (DPS) that produces SCN arrhythmia. MSG treatments induced hypogonadism and obesity, retain-->and markedly reduced the size of the optic chiasm and optic nerves. MSG-treated hamsters exhibited normal entrainment to the light-dark cycle, but MSG treatretain-->ment counteracted the circadian arrhythmicity induced by the DPS protocol: only 6% of retain-->MSG-treated hamsters exhibited circadian arrhythmia, whereas 50% of control hamsters were circadian disrupted. In MSG-treated hamsters that retained circadian rhythmicity after DPS treatment, quantitative parameters of URs appeared normal, but in the two MSG-treated hamsters that became circadian arrhythmic after DPS, both dark-phase and light-phase URs were abolished. Although preliminary, these data are consistent with reports in voles suggesting that the combined disruption of SCN and ARC function impairs the expression of behavioral URs. The data also suggest that light thresholds for entrainment of circadian rhythms may be lower than those required to disrupt circadian organization.

  10. Evolution of mammal tooth patterns: new insights from a developmental prediction model. (United States)

    Renvoisé, Elodie; Evans, Alistair R; Jebrane, Ahmad; Labruère, Catherine; Laffont, Rémi; Montuire, Sophie


    The study of mammalian evolution is often based on insights into the evolution of teeth. Developmental studies may attempt to address the mechanisms that guide evolutionary changes. One example is the new developmental model proposed by Kavanagh et al. (2007), which provides a high-level testable model to predict mammalian tooth evolution. It is constructed on an inhibitory cascade model based on a dynamic balance of activators and inhibitors, regulating differences in molar size along the lower dental row. Nevertheless, molar sizes in some mammals differ from this inhibitory cascade model, in particular in voles. The aim of this study is to point out arvicoline and murine differences within this model and to suggest an alternative model. Here we demonstrate that the inhibitory cascade is not followed, due to the arvicoline's greatly elongated first lower molar. We broaden the scope of the macroevolutionary model by projecting a time scale onto the developmental model. We demonstrate that arvicoline evolution is rather characterized by a large gap from the oldest vole to more recent genera, with the rapid acquisition of a large first lower molar contemporaneous to their radiation. Our study provides alternative evolutionary hypotheses for mammals with different trajectories of development.

  11. Chronic wasting disease (CWD) susceptibility of several North American rodents that are sympatric with cervid CWD epidemics (United States)

    Heisey, D.M.; Mickelsen, N.A.; Schneider, J.R.; Johnson, C.J.; Langenberg, J.A.; Bochsler, P.N.; Keane, D.P.; Barr, D.J.


    Chronic wasting disease (CWD) is a highly contagious always fatal neurodegenerative disease that is currently known to naturally infect only species of the deer family, Cervidae. CWD epidemics are occurring in free-ranging cervids at several locations in North America, and other wildlife species are certainly being exposed to infectious material. To assess the potential for transmission, we intracerebrally inoculated four species of epidemic-sympatric rodents with CWD. Transmission was efficient in all species; the onset of disease was faster in the two vole species than the two Peromyscus spp. The results for inocula prepared from CWD-positive deer with or without CWD-resistant genotypes were similar. Survival times were substantially shortened upon second passage, demonstrating adaptation. Unlike all other known prion protein sequences for cricetid rodents that possess asparagine at position 170, our red-backed voles expressed serine and refute previous suggestions that a serine in this position substantially reduces susceptibility to CWD. Given the scavenging habits of these rodent species, the apparent persistence of CWD prions in the environment, and the inevitable exposure of these rodents to CWD prions, our intracerebral challenge results indicate that further investigation of the possibility of natural transmission is warranted. Copyright ?? 2010, American Society for Microbiology. All Rights Reserved.

  12. Intraspecific variation of Taenia taeniaeformis as determined by various criteria. (United States)

    Azuma, H; Okamoto, M; Oku, Y; Kamiya, M


    The intraspecific variation of four laboratory-reared isolates of Taenia taeniaformis the SRN and KRN isolates from Norway rats, Rattus norvegicus, captured in Japan and Malaysia, respectively; the BMM isolated from a house mouse, Mus musculus, captured in Belgium; and the ACR isolate from a gray red-backed vole, Clethrionomys rufocanus bedfordiae, captured in Japan was examined by various criteria. Eggs of each of the four isolates were orally inoculated into several species of intermediate host. They were most infective to the rodent species from which the original metacestode of each isolate had been isolated in the field, and only the ACR isolate was infective to the gray red-backed vole. Although little difference was found between the SRN, KRN, and BMM isolates by the other criteria, including the morphology of rostellar hooks, the protein composition of the metacestode, and restriction endonuclease analysis of DNA, the ACR isolate was clearly different from the others. It was considered that the ACR isolate was independent as a strain distinct from the other three isolates.

  13. Oxytocin receptor density is associated with male mating tactics and social monogamy. (United States)

    Ophir, Alexander G; Gessel, Ana; Zheng, Da-Jiang; Phelps, Steven M


    Despite its well-described role in female affiliation, the influence of oxytocin on male pairbonding is largely unknown. However, recent human studies indicate that this nonapeptide has a potent influence on male behaviors commonly associated with monogamy. Here we investigated the distribution of oxytocin receptors (OTR) throughout the forebrain of the socially monogamous male prairie vole (Microtus ochrogaster). Because males vary in both sexual and spatial fidelity, we explored the extent to which OTR predicted monogamous or non-monogamous patterns of space use, mating success and sexual fidelity in free-living males. We found that monogamous males expressed higher OTR density in the nucleus accumbens than non-monogamous males, a result that mirrors species differences in voles with different mating systems. OTR density in the posterior portion of the insula predicted mating success. Finally, OTR in the hippocampus and septohippocampal nucleus, which are nuclei associated with spatial memory, predicted patterns of space use and reproductive success within mating tactics. Our data highlight the importance of oxytocin receptor in neural structures associated with pairbonding and socio-spatial memory in male mating tactics. The role of memory in mating systems is often neglected, despite the fact that mating tactics impose an inherently spatial challenge for animals. Identifying mechanisms responsible for relating information about the social world with mechanisms mediating pairbonding and mating tactics is crucial to fully appreciate the suite of factors driving mating systems. This article is part of a Special Issue entitled Oxytocin, Vasopressin, and Social Behavior.

  14. The Population Structure and Dynamics of Small Mammals in Set Aside Areas in Western Switzerland%瑞士西部农田周围生态保留带中小型兽类种群结构特征及数量动态的初步研究

    Institute of Scientific and Technical Information of China (English)

    艾尼瓦尔·吐米尔; Jean-Pierre Airoldi; Wolfgang Nentwig; 马合木提·哈力克


    为了评价生态保留带对小型兽类种群的影响,2003年7月至2004年6月在瑞士西部Salavaux, Chevroux 和Montbrelloz 3个地区采用标志重捕方法对小型兽类种群进行了研究.在3个生态保留带中,共发现6种1 206只小型兽类,其中普通田鼠、小林姬鼠、中麝捕获数量多.普通田鼠为优势种.普通田鼠的种群数量在生态保留带间有差异,但具有相同的季节性波动趋势,一般种群数量随着植被覆盖度和食物丰富度的增加,春季末开始出现增加,仲夏达到最高水平.种群中雌雄个体年龄结构之间有明显的差异,成体和亚成体的数量比幼体多,雄性亚成体的数量比雌性多,雌性成体数量比雄性多(x2 =44.09,df=10, P< 0.001,N=203). 普通田鼠种群中雌雄个体体重之间有明显的差异,雄性的体重比雌性大(t-检验: t=5.011, df= 162, P<0.05,N=213).种群性比之间有明显的月间变化,雌性的捕获次数比雄性大.普通田鼠只在短距离范围内活动,在生态保留带中的巢区为350~400 m2,雌雄个体的巢区大小之间没有显著性差异.%In this paper in order to assess the effect of set aside to small mammal populations, one year field study using mark and recapture method was performed in set aside fields in Salavaux, Chevroux and Montbrelloz in western Switzerland. There are 3 species were regularly caught in the set asides: the common vole(Microtus arvalis), the white toothed shrew(Crocidura russula), and the wood mouse(Apodemus sylvaticus). The common vole was the most numerous species in the three set aside fields. Population size of common voles was different between the set aside, but fluctuations in animal numbers were similar, showing a rapid increase as cover and food abundance increased in the set asides during late spring, leading to peak in midsummer. The age structure differed between males and females, most individuals captured during this study are adults and subadults. There

  15. Population cycles in small rodents. (United States)

    Krebs, C J; Gaines, M S; Keller, B L; Myers, J H; Tamarin, R H


    We conclude that population fluctuations in Microtus in southern Indiana are produced by a syndrome of changes in birth and death rates similar to that found in other species of voles and lemmings. The mechanisms which cause the changes in birth and death rates are demolished by fencing the population so that no dispersal can occur. Dispersal thus seems critical for population regulation in Microtus. Because most dispersal occurs during the increase phase of the population cycle and there is little dispersal during the decline phase, dispersal is not directly related to population density. Hence the quality of dispersing animals must be important, and we have found one case of increased dispersal tendency by one genotype. The failure of population regulation of Microtus in enclosed areas requires an explanation by any hypothesis attempting to explain population cycles in small rodents. It might be suggested that the fence changed the predation pressure on the enclosed populations. However, the fence was only 2 feet (0.6 meter) high and did not stop the entrance of foxes, weasels, shrews, or avian predators. A striking feature was that the habitat in the enclosures quickly recovered from complete devastation by the start of the spring growing season. Obviously the habitat and food quality were sufficient to support Microtus populations of abnormally high densities, and recovery of the habitat was sufficiently quick that the introduction of new animals to these enclosed areas resulted in another population explosion. Finally, hypotheses of population regulation by social stress must account for the finding that Microtus can exist at densities several times greater than normal without "stress" taking an obvious toll. We hypothesize that the prevention of dispersal changes the quality of the populations in the enclosures in comparison to those outside the fence. Voles forced to remain in an overcrowded fenced population do not suffer high mortality rates and continue

  16. Structure transformations of endocrine system organs during adaptation to increased radioactivity

    Energy Technology Data Exchange (ETDEWEB)

    Ermakova, O.V. [Institute of Biology, Komi Scientific Centre, Ural Division of Russian Academy of Sciences, Syktyvkar (Russian Federation)


    It is well known that during ecological monitoring of contaminated territories registration of early abnormalities in an organism is hampered by man-caused influence of habitat. Under these circumstances study of both structural and functional changes in organs and tissues of rodents inhabiting radioactive contaminated territories is of great importance. Study of structural features of endocrine glands, hormones of which trigger the process of active adaptive changes in an organism, is very important in radioecological surveys. Basing on long-term study of voles we have determined that long-term living by rodents on the territories characterized by increased natural and artificial radioactivity (radium contaminated fields in the Komi Republic and 30-km zone of Chernobyl APS) substantially influences morpho-functional state of endocrine system organs, causing quantitative and qualitative changes. It is demonstrated that population processes modify biological consequences of small doze chronic ionizing radiation in habitat. We noticed the following: high heterogeneity of histological changes of thyroid gland and adrenal gland as a response to radioactive habitat contamination; disorder of interconnection among different links of endocrine system; dependence of radiation effects on gender, age, degree and character of radiation contamination of a habitat as well as duration of radioactive influence. We have got data on morphological characteristics of thyroid gland and adrenal gland during different phases of population amount of this kind of rodents. It was discovered that effectiveness of radiation influence is not the same during different periods of population cycle. Presence of voles on the territories characterized by increased radioactivity causes chronic tension of adrenal cortex (increasing of the organ mass, enlarging of thickness of zona fasciculata and zona reticularis). Destructive-necrotic processes combine with manifestation of reparative regeneration

  17. Effective Control of Non-Native American Mink by Strategic Trapping in a River Catchment in Mainland Britain. (United States)

    Reynolds, Jonathan C; Richardson, Suzanne M; Rodgers, Ben J E; Rodgers, Owain R K


    The introduction of American mink (Neovison vison; hereafter mink) into Europe has had severe impacts on many native wildlife species, including the water vole (Arvicola amphibius) in mainland Britain. Although trapping has been widely used to attempt to control mink, managers have little direct evidence of its effect on mink density or distribution, particularly where immigration of mink from nearby areas is inevitable. Such evidence is needed to justify the use of lethal methods in conservation policy. During 2006-2010 we removed mink from the River Monnow Catchment in western Britain, using track-recording rafts to monitor continuously for mink presence, guiding a strategic trapping effort. The area monitored and trapped was increased in stages, from a core sub-catchment with 109 km of water-course in 2006, to a 421-km(2) catchment with 203 km of water-course in 2009. In each successive sub-catchment, mink detection and capture rates declined rapidly to near-zero levels after trapping began. Detections and captures showed seasonal peaks in every year corresponding to known dispersal periods, but also declined steadily from year to year, with increasing periods in which we did not detect mink. These results suggested that each sub-catchment was cleared of mink within a few months, with subsequent captures attributable to immigration. On average, we detected each mink 5.1 times before capture (daily probability of detection = 0.059 per mink and raft), and trapped them 3.4 days after deploying traps in response. On average, mink entering the area were likely to have been present for less than 13 days before capture. Water voles had been extinct in the Monnow Catchment since the 1980s. During 2006-2008 (starting 6 months after mink trapping commenced), we released 700 captive-bred water voles into the treatment area to re-establish a wild population. Persistence of this population through the 4 years of the project was considered indicative of effective mink control

  18. Calodium (Capillaria hepaticum (Nematoda, Capillariidae in insular small rodent populations

    Directory of Open Access Journals (Sweden)

    Bugmyrin Sergey


    Full Text Available The data on the distribution of the nematode Calodium hepaticum (Bancroft 1893 Moravec 1982 (syn.: Capillaria hepatica, Hepaticola hepatica on the islands of Kizhi Archipelago are reported (N 62°00'; E 35°12'. Samples were collected on 18 islands and the mainland part of the Kizhi skerries region in the period from August 2005 till 2014. The method of partial helminthological dissection was applied to 346 specimens of rodents belonging to two species – the bank vole Myodes glareolus Schreber 1780 (301 spm. and the field vole Microtus agrestis Linnaeus 1761 (45 spm.. The prevalence and the abundance index of nematode were 16.6% and 1.1 in M. glareolus and 11.1%; 0.3 in M. agrestis, respectively. The highest prevalence and abundance of C. hepaticum were detected in mature voles. No sex-related differences were found. C. hepaticum was present in 12 of 19 sampling sites. On the islands where the sample number (host individuals was over 15, the highest prevalence and abundance values were 57% and 5.8 spm., respectively. Significant positive coefficients of correlation (Spearman’s and Pearson’s ones between nematode numbers and characteristics of the island were found in the pair «Prevalence – degree of isolation» (0.48 and 0.49. Single-factor analysis of variance showed that the size of the island had some effect on the nematode invasion prevalence and abundance. However, no significant regression relationship between the prevalence and abundance of nematodes and characteristics of an island was revealed by multivariate regression analysis (multiple regression: the coefficient of determination of the regression equation R2 < 0.3, and the regression coefficients were insignificant The reasons for high abundance of C. hepaticum in northern insular ecosystems are discussed. Possible key factors for the stable vitality of the parasite populations are: 1 favourable hydrothermal conditions of the soil in the shore (littoral zone; 2 the

  19. Populations of Clethrionomys glareolus in three isolated forest complexes in rural southern Moravia (Czech Republic

    Directory of Open Access Journals (Sweden)

    Josef Suchomel


    Full Text Available Abstract In rural landscapes, the dynamics of bank vole (Clethrionomys glareolus populations were studied from 2002 to 2005 in three large isolated forest complexes which differed in tree composition and food supply. Populations fluctuated markedly during the four years of research. Extra seed crop in 2003 and probable niche vacation - the density of the dominant Apodemus flavicollis lowered in 2004 -, determined two years (2004-05 of higher bank vole population densities. The relative abundance of C. glareolus was higher in the most variable biotope (RB, consisting of an intensive pheasantry. Also the body mass of adult individuals, particularly females, was higher in RB. The influence of seed crop on the weight of individuals was statistically significant. During winter 2004/2005 a strong impact on the forest regeneration in tree plantings was reported. We argue that vole abundance prediction by periodical monitoring is needed to prevent damage. Riassunto Popolazioni di Clethrionomys glareolus in tre complessi forestali di un’area agricola della Moravia meridionale (Repubblica Ceca La dinamica di popolazione di C. glareolus è stata indagata in tre complessi forestali relitti in ambiente rurale, differenti sia per aspetti vegetazionali sia riguardo la disponibilità di risorse alimentari. L’abbondanza relativa (rA dell’arvicola rossastra ha mostrato ampie oscillazioni nei tre siti, in parte da ricollegare a una produzione eccezionale di ghiande nell’autunno 2003 e a un decremento di A. flavicollis (specie dominante nel 2004, che hanno determinato due anni consecutivi (2004-05 di rA elevate per C. glareolus. Nel complesso, i valori di rA sono risultati maggiori nel biotopo più diversificato, così come anche la massa corporea degli adulti, in particolare delle femmine. La produzione di semi del 2003 ha anche influito

  20. Environmental conditions and Puumala virus transmission in Belgium

    Directory of Open Access Journals (Sweden)

    Leirs Herwig


    Full Text Available Abstract Background Non-vector-borne zoonoses such as Puumala hantavirus (PUUV can be transmitted directly, by physical contact between infected and susceptible hosts, or indirectly, with the environment as an intermediate. The objective of this study is to better understand the causal link between environmental features and PUUV prevalence in bank vole population in Belgium, and hence with transmission risk to humans. Our hypothesis was that environmental conditions controlling the direct and indirect transmission paths differ, such that the risk of transmission to humans is not only determined by host abundance. We explored the relationship between, on one hand, environmental variables and, on the other hand, host abundance, PUUV prevalence in the host, and human cases of nephropathia epidemica (NE. Statistical analyses were carried out on 17 field sites situated in Belgian broadleaf forests. Results Linear regressions showed that landscape attributes, particularly landscape configuration, influence the abundance of hosts in broadleaf forests. Based on logistic regressions, we show that PUUV prevalence among bank voles is more linked to variables favouring the survival of the virus in the environment, and thus the indirect transmission: low winter temperatures are strongly linked to prevalence among bank voles, and high soil moisture is linked to the number of NE cases among humans. The transmission risk to humans therefore depends on the efficiency of the indirect transmission path. Human risk behaviours, such as the propensity for people to go in forest areas that best support the virus, also influence the number of human cases. Conclusion The transmission risk to humans of non-vector-borne zoonoses such as PUUV depends on a combination of various environmental factors. To understand the complex causal pathways between the environment and disease risk, one should distinguish between environmental factors related to the abundance of hosts

  1. The effects of spatial and temporal heterogeneity on the population dynamics of four animal species in a Danish landscape

    Directory of Open Access Journals (Sweden)

    Forchhammer Mads C


    Full Text Available Abstract Background Variation in carrying capacity and population return rates is generally ignored in traditional studies of population dynamics. Variation is hard to study in the field because of difficulties controlling the environment in order to obtain statistical replicates, and because of the scale and expense of experimenting on populations. There may also be ethical issues. To circumvent these problems we used detailed simulations of the simultaneous behaviours of interacting animals in an accurate facsimile of a real Danish landscape. The models incorporate as much as possible of the behaviour and ecology of skylarks Alauda arvensis, voles Microtus agrestis, a ground beetle Bembidion lampros and a linyphiid spider Erigone atra. This allows us to quantify and evaluate the importance of spatial and temporal heterogeneity on the population dynamics of the four species. Results Both spatial and temporal heterogeneity affected the relationship between population growth rate and population density in all four species. Spatial heterogeneity accounted for 23–30% of the variance in population growth rate after accounting for the effects of density, reflecting big differences in local carrying capacity associated with the landscape features important to individual species. Temporal heterogeneity accounted for 3–13% of the variance in vole, skylark and spider, but 43% in beetles. The associated temporal variation in carrying capacity would be problematic in traditional analyses of density dependence. Return rates were less than one in all species and essentially invariant in skylarks, spiders and beetles. Return rates varied over the landscape in voles, being slower where there were larger fluctuations in local population sizes. Conclusion Our analyses estimated the traditional parameters of carrying capacities and return rates, but these are now seen as varying continuously over the landscape depending on habitat quality and the mechanisms

  2. Interview de Simon Chignard

    Directory of Open Access Journals (Sweden)

    Matthieu Noucher


    Full Text Available Simon Chignard est l’auteur de « L’open data, comprendre l’ouverture des données publiques » (FYP éditions, mars 2012. Dans ce livre il propose des repères pour replacer l’open data dans le contexte français et comprendre les enjeux et les limites de l’ouverture des données publiques. Il a participé dès 2010 à l’animation de l’ouverture des données publiques de Rennes Métropole, territoire pionnier en France. Consultant et formateur indépendant, il est à titre bénévole président de l’association Bug (innovation sociale et numérique et vice-président de la Cantine numérique rennaise. Il anime le blog :

  3. Congruent responses to weather variability in high arctic herbivores. (United States)

    Stien, Audun; Ims, Rolf A; Albon, Steve D; Fuglei, Eva; Irvine, R Justin; Ropstad, Erik; Halvorsen, Odd; Langvatn, Rolf; Loe, Leif Egil; Veiberg, Vebjørn; Yoccoz, Nigel G


    Assessing the role of weather in the dynamics of wildlife populations is a pressing task in the face of rapid environmental change. Rodents and ruminants are abundant herbivore species in most Arctic ecosystems, many of which are experiencing particularly rapid climate change. Their different life-history characteristics, with the exception of their trophic position, suggest that they should show different responses to environmental variation. Here we show that the only mammalian herbivores on the Arctic islands of Svalbard, reindeer (Rangifer tarandus) and sibling voles (Microtus levis), exhibit strong synchrony in population parameters. This synchrony is due to rain-on-snow events that cause ground ice and demonstrates that climate impacts can be similarly integrated and expressed in species with highly contrasting life histories. The finding suggests that responses of wildlife populations to climate variability and change might be more consistent in Polar regions than elsewhere owing to the strength of the climate impact and the simplicity of the ecosystem.

  4. Advantage of rare infanticide strategies in an invasion experiment of behavioural polymorphism. (United States)

    Mappes, Tapio; Aspi, Jouni; Koskela, Esa; Mills, Suzanne C; Poikonen, Tanja; Tuomi, Juha


    Killing conspecific infants (infanticide) is among the most puzzling phenomena in nature. Stable polymorphism in such behaviour could be maintained by negative frequency-dependent selection (benefit of rare types). However, it is currently unknown whether there is genetic polymorphism in infanticidal behaviour or whether infanticide may have any fitness advantages when rare. Here we show genetic polymorphism in non-parental infanticide. Our novel invasion experiment confirms negative frequency-dependent selection in wild bank vole populations, where resource benefits allow an infanticidal strategy to invade a population of non-infanticidal individuals. The results show that infanticidal behaviour is highly heritable with genetic correlation across the sexes. Thus, a positive correlative response in male behaviour is expected when selection operates on females only and vice versa. Our results, on one hand, demonstrate potential benefits of infanticide, and on the other, they open a new perspective of correlative evolution of infanticide in females and males.

  5. Sex differences in microglial colonization and vulnerabilities to endocrine disruption in the social brain. (United States)

    Rebuli, Meghan E; Gibson, Paul; Rhodes, Cassie L; Cushing, Bruce S; Patisaul, Heather B


    During development, microglia, the resident immune cells of the brain, play an important role in synaptic organization. Microglial colonization of the developing brain is sexually dimorphic in some regions, including nuclei critical for the coordination of social behavior, suggesting steroid hormones have an influencing role, particularly estrogen. By extension, microglial colonization may be vulnerable to endocrine disruption. Concerns have been raised regarding the potential for endocrine disrupting compounds (EDCs) to alter brain development and behavior. Developmental exposure to Bisphenol A (BPA), a ubiquitous EDC, has been associated with altered sociosexual and mood-related behaviors in various animal models and children. Through a comparison of the promiscuous Wistar rat (Rattus norvegicus) and the socially monogamous prairie vole (Microtus ochrogaster), we are the first to observe that developmental exposure to the synthetic estrogen ethinyl estradiol (EE) or BPA alters the sex-specific colonization of the hippocampus and amygdala by microglia.

  6. Implications of increased susceptibility to predation for management of the sylvatic cycle of Echinococcus multilocularis

    DEFF Research Database (Denmark)

    Vervaeke, V; Davis, S; Leirs, Herwig;


    to predation in the intermediate host reduces the sensitivity of the parasite population to adverse conditions. For example, there is no critical density of foxes below which the parasite is expected to die out, even if the effect of the parasite on infected prey is very small. We suggest that increased......The ability to increase the chances that infectious prey are taken by predators is an observed feature of many parasites that rely on one or more predator-prey relationships to complete their life-cycle. In the sylvatic life-cycle of Echinococcus multilocularis - the causative agent of human...... alveolar echinococcosis - foxes are the final host, with voles acting as intermediate hosts. Here we review the evidence that E. multilocularis causes increased susceptibility to predation and present a general mathematical model for the sylvatic life-cycle. The ability to increase susceptibility...

  7. Offering solutions of sustainable urban tourism by the use of SWOT model, case study Isfahan city

    Directory of Open Access Journals (Sweden)

    Monireh Roustazadeh Sheikh Yousefi


    Full Text Available Tourism phenomenon has been spread world wildtoday. It's because of technological innovation development and overallcapitalism expansion in current age. Tourism in this situation has caused humanbeing relocation and mobility and in worldwide level, has created concept ofrelationship with other cultures in different locations, as socio-geographicalphenomenon. In this case cities includes important scientific, recreational,sport, shrine, historical, culture, medical, centers, etc., in addition to thiscases, also utilities natural attraction, etc., can play vole as touristic cityin the center of the country. in this research discursive- analysis method hasbeen used for collecting data and proceed to identify tourism potentials ,abilities, limitations and inadequacy of Isfahan by documental and librarydeliberations and field studies, SWOT model has been used for analyzing data.Then, offering solutions for sustainable urban development and eventuallymovement toward tourism development have been emphasized on.

  8. [An assessment of the status of natural foci of Crimean-Congo hemorrhagic fever in the Crimea]. (United States)

    Markeshin, S Ia; Smirnova, S E; Evstaf'ev, I L


    The parasitological data and the results of the virological and serological investigations of materials, collected in nature and in the course of study of the immune structure of the population, are indicative of the circulation of CHF virus in the Crimea and the possibility of human infection. Data on spontaneous infection of four species of Ixodes ticks with CHF virus have been confirmed, including the data, obtained for the first time for this region, on the participation of Dermacentor marginatus in this process. The study has revealed, also for the first time, that, together with European brown hares, the natural foci of this infection may be maintained by scilly shrews, common voles and European wood mice. Low activity of the Crimean focus may be the result of active land reclamation, keeping the cattle stalled in most of the stock-breeding farms of the region, as well as a sharp decline in the number of hares at the territories of hunting preserves.

  9. [An evaluation of the status of natural foci of Crimean-Congo hemorrhagic fever in the Crimea]. (United States)

    Markeshin, S Ia; Smirnova, S E; Evstaf'ev, I L


    Parasitological data, the results of virological and serological investigations of materials, collected in nature and during the study of the immune structure of the population and indicative of the circulation of CCHF, virus in the Crimea and the possibility of human infection, are presented. The data on the spontaneous CCHF virus infection of 4 tick species belonging to the genus Ixodes have been confirmed, and evidence on the participation of Dermacentor marginatus in this process obtained for the first time in this region. The study has revealed for the first time that, besides European brown hares, scilly shrews, common voles and field mice may contribute to the maintenance of the natural foci of this infection. The low activity of the Crimean focus of CCHF may be the result of the intensive use of land, the widely spread stall-feeding of cattle, as well as a sharp decrease in the number of hares on the territories of hunting preserves.

  10. Evaluation of management practices in wetland meadows at Grays Lake National Wildlife Refuge, Idaho, 1997-2000 (United States)

    Austin, J.E.; Pyle, W.H.; Keough, J.R.; Johnson, D.H.


    experimental units, the most common were American coot, sandhill crane, Canada goose, American avocet, mallard, and cinnamon teal. Daily survival rates (DSRs) of dabbling duck nests (all species pooled) were negatively affected by fall grazing. We detected no effects of treatments on DSRs of Canada geese or sandhill crane nests. DSRs for sandhill crane nests were higher in 1998 than in 1999 or 2000 and were slightly higher than that in 1997. DSRs for coot nests were affected by both year and treatment; within-treatment differences among years were extensive, In 1998, when all units were idled, DSRs for coot nests were higher in units assigned to idle treatment than those assigned to fall-grazed or rotation treatment. DSRs for coot nests did not differ among treatment blocks in 1997 (all units idled) or 1999 (first year after treatments). We speculate that compaction of residual vegetation by snowpack reduced any differences between idle and treated units and thus lessened the value of idle habitat for most nesting birds. Nesting densities and nest success rates of Canada geese, dabbling ducks, and sandhill cranes were lower those that reported from Steel's (1952) study in 1949-1950, but differences in habitats and areas searched relative to our study make comparisons difficult. Nest success rates of sandhill cranes also were lower than those reported by Drewien (1973). Declines in nest success probably are related to changes in predator community. We captured 5 species of small mammals (meadow vole, montane vole, deer mouse, vagrant shrew, and ermine). Populations of meadow and montane voles irrupted in 1998 then crashed in spring 1999; the most marked changes were in montane vole numbers. Capture rates of ermine and observation rates for striped skunks and raptors suggested a numerical response (higher recruitment) by these predators to higher prey abundance and possibly distributional shifts (movement into areas of more abundant microtines). We did not detect differences

  11. New microbial growth factor (United States)

    Bok, S. H.; Casida, L. E., Jr.


    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  12. On the systematic position of Collyricloides massanae Vaucher, 1969 (Platyhelminthes: Digenea) with notes on distribution of this trematode species. (United States)

    Kanarek, Gerard; Zaleśny, Grzegorz; Czujkowska, Agnieszka; Sitko, Jiljí; Harris, Philip D


    The systematic position of the Collyricloides massanae, a rare cyst-dwelling parasite, located on intestinal wall of European birds and rodents, have always been controversial. Based on newly obtained sequences of the 28 sDNA of C. massanae from avian and rodent host from Central Europe, and on the previously published sequences of several genera and families among Microphalloidea, we evaluate its taxonomic position and the phylogenetic relationships within the genera Collyriclum Kossack, 1911 and Collyricloides Vaucher, 1969 which form the family Collyriclidae Ward, 1917. In the cladogram, C. massanae appears among the Pleurogenidae, forming a clade with Gyrabascus amphoraeformis (Modlinger, 1930) and Cortrema magnicaudata (Bykhovskaya-Pavlovskaya, 1950). We reject the commonly accepted placement of Collyricloides as the sister genus to Collyriclum within the Collyriclidae. Besides, we present and discuss the unusual records of C. massanae in the bank vole Myodes glareolus from northeastern Poland.

  13. Analysis of capture-recapture models with individual covariates using data augmentation (United States)

    Royle, J. Andrew


    I consider the analysis of capture-recapture models with individual covariates that influence detection probability. Bayesian analysis of the joint likelihood is carried out using a flexible data augmentation scheme that facilitates analysis by Markov chain Monte Carlo methods, and a simple and straightforward implementation in freely available software. This approach is applied to a study of meadow voles (Microtus pennsylvanicus) in which auxiliary data on a continuous covariate (body mass) are recorded, and it is thought that detection probability is related to body mass. In a second example, the model is applied to an aerial waterfowl survey in which a double-observer protocol is used. The fundamental unit of observation is the cluster of individual birds, and the size of the cluster (a discrete covariate) is used as a covariate on detection probability.

  14. Isolation of pathogenic Yersinia enterocolitica 1B/O:8 from Apodemus mice in Japan. (United States)

    Oda, Shinya; Kabeya, Hidenori; Sato, Shingo; Shimonagane, Ai; Inoue, Kai; Hayashidani, Hideki; Takada, Nobuhiro; Fujita, Hiromi; Kawabata, Hiroki; Maruyama, Soichi


    Yersinia enterocolitica was isolated from 15.7% (88/560) of wild rodents captured in 15 prefectures in Japan. Prevalences by rodent species were 18.0% (70/388) in Japanese field mice (Apodemus speciosus), 20% (14/71) in small Japanese field mice (Apodemus argenteus), and 11% (4/38) in gray red-backed vole (Myodes rufocanus bedfordiae), suggesting that these rodent species are important reservoirs of Y. enterocolitica. Although most of the isolates were identified as biotype 1A, the pathogenic bioserotype 1B/O:8 was detected in one of the A. speciosus and in three of the A. argenteus captured in Aomori Prefecture. It is suggested that Apodemus mice may be an important reservoir of Y. enterocolitica, and that there are foci of the pathogenic bioserotype 1B/O:8 in Aomori Prefecture, because human sporadic cases by the serotype have been reported in this prefecture.

  15. Polyandry enhances offspring survival in an infanticidal species. (United States)

    Klemme, Ines; Ylönen, Hannu


    The adaptive significance of polyandry is an intensely debated subject in sexual selection. For species with male infanticidal behaviour, it has been hypothesized that polyandry evolved as female counterstrategy to offspring loss: by mating with multiple males, females may conceal paternity and so prevent males from killing putative offspring. Here we present, to our knowledge, the first empirical test of this hypothesis in a combined laboratory and field study, and show that multiple mating seems to reduce the risk of infanticide in female bank voles Myodes glareolus. Our findings thus indicate that females of species with non-resource based mating systems, in which males provide nothing but sperm, but commit infanticide, can gain non-genetic fitness benefits from polyandry.

  16. Quel modèle de gouvernance pour les associations ?


    Biondi, Yuri; Chatelain-Ponroy, Stéphanie; Eynaud, Philippe; Sponem, Samuel


    Avec un budget cumulé de 59 milliards d'euros en 2007, un volume d'emploi de plus d'un million d'emploi en équivalent temps plein, 14 millions de bénévoles, les associations (dont le nombre dépasse le million) ont un poids considérable dans l'économie française. Par ailleurs, elles ont de plus en plus tendance à se professionnaliser, à adopter des méthodes de management et à généraliser leur recours aux outils de gestion. Ce phénomène, observable dans de nombreux pays, s'accompagne de l'appar...

  17. The neurobiology of social attachment: A comparative approach to behavioral, neuroanatomical, and neurochemical studies. (United States)

    Young, Kimberly A; Liu, Yan; Wang, Zuoxin


    The formation and maintenance of social bonds in adulthood is an essential component of human health. However studies investigating the underlying neurobiology of such behaviors have been scarce. Microtine rodents offer a unique comparative animal model to explore the neural processes responsible for pair bonding and its associated behaviors. Studies using monogamous prairie voles and other related species have recently offered insight into the neuroanatomical, neurobiological, and neurochemical underpinnings of social attachment. In this review, we will discuss the utility of the microtine rodents in comparative studies by exploring their natural history and social behavior in the laboratory. We will then summarize the data implicating vasopressin, oxytocin, and dopamine in the regulation of pair bonding. Finally, we will discuss the ways in which these neurochemical systems may interact to mediate this complex behavior.

  18. Could oxytocin administration during labor contribute to autism and related behavioral disorders?--A look at the literature. (United States)

    Wahl, Roy U Rojas


    This literature review summarizes recent potential evidence, most of which is at the molecular/mechanistic level, in support of Hollander's hypothesis that excess oxytocin (OT), possibly through OT administration at birth, could contribute to the development of autistic spectrum disorders and related syndromes by proposed down regulation of the OT receptor (OTR). In this review, recent molecular evidence for OTR internalization by excess OT is related to OT's reported effects on animal social behavior, favoring social bondage, notably in sheep, voles, rats and especially mice. Adding indications for OT's capability of crossing the maternal placenta and OT's possibility of crossing an underdeveloped or stressed infantile blood brain barrier at birth, a causal connection between OT excess and behavioral disorders such as autism can be supported from a molecular perspective. Possible strategies such as a thorough statistical analysis of numerous birth records as well as molecular studies such as radiotracing using labeled OT are proposed to test this hypothesis.

  19. [Helminth fauna and steroid hormones concentration of wild rodents]. (United States)

    Kuliś, Karolina; Bajer, Anna; Siński, Edward


    Fragmentation of the environment by natural barriers (lakes, mountain ranges) and human activities (towns, major roads, agriculture) can lead to isolate subpopulations of hosts. The study was based in Mazury lake district in north-eastern Poland, the region rich in forests, lakes, rivers and canals, which can create impassable barriers. Population of bank voles (Clethrionomys glareolus)--dominant woodland rodent--showed local differences in helminth communities in fragmented forest habitat. The sites were chosen on the basis of the similarity of their habitat structure and type, and isolation from one another. There are evidences that steroids hormones associated with stress and reproduction may mediate trade-offs between physiology and immune function.

  20. The structure of small mammal communities in some alpine habitats

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    Roberta Locatelli


    Full Text Available Abstract We studied the composition of several small mammal communities living in different mountain and forest habitats of the central eastern Italian Alps. The small mammals were then grouped together, by cluster analysis, according to similarities in species and density. From the 22 stations investigated, five groups emerged, each one having also distinct environmental characteristics. We observed that spruce forest communities are grouped separately from those of mixed forests (larch and Swiss stone pine. We must stress the considerable difference existing between the small mammal communities living in different kinds of coniferous forests. The larch and Swiss stone pine forest seem to be able to support a greater density of small mammals, which includes in particular the bank vole (Clethrionomys glareolus.

  1. Contribution to the distribution of terrestrial small mammals in the Sǎlaj county, Romania

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    Gubányi A.


    Full Text Available During the research period (2014-2015 287 small mammals, five species of shrews and eight species of rodents (Crocidura leucodon, C. suaveolens, Sorex araneus, S. minutus, Neomys anomalus, Microtus agrestis M. arvalis, M. subterraneus, Myodes glareolus. Apodemus agrarius, A. flavicollis, A. sylvaticus, A. uralensis were detected in the Sǎlaj County. The striped field mouse (Apodemus agrarius and the common vole (Microtus arvalis proved to be the characteristic dominant species of the small mammal communities investigated in this area. The number of terrestrial small mammalian species lagged behind our expectations. Micromys minutus was not collected during the research period in the habitats characterized by reed-bed and/or tall sedge vegetation.

  2. Hantaviruses and climate change. (United States)

    Klempa, B


    Most hantaviruses are rodent-borne emerging viruses. They cause two significant human diseases, haemorrhagic fever with renal syndrome in Asia and Europe, and hantavirus cardiopulmonary syndrome in the Americas. Very recently, several novel hantaviruses with unknown pathogenic potential have been identified in Africa and in a variety of insectivores (shrews and a mole). Because there is very limited information available on the possible impact of climate change on all of these highly dangerous pathogens, it is timely to review this aspect of their epidemiology. It can reasonably be concluded that climate change should influence hantaviruses through impacts on the hantavirus reservoir host populations. We can anticipate changes in the size and frequency of hantavirus outbreaks, the spectrum of hantavirus species and geographical distribution (mediated by changes in population densities), and species composition and geographical distribution of their reservoir hosts. The early effects of global warming have already been observed in different geographical areas of Europe. Elevated average temperatures in West-Central Europe have been associated with more frequent Puumala hantavirus outbreaks, through high seed production (mast year) and high bank vole densities. On the other hand, warm winters in Scandinavia have led to a decline in vole populations as a result of the missing protective snow cover. Additional effects can be caused by increased intensity and frequency of extreme climatic events, or by changes in human behaviour leading to higher risk of human virus exposure. Regardless of the extent of climate change, it is difficult to predict the impact on hantavirus survival, emergence and epidemiology. Nevertheless, hantaviruses will undoubtedly remain a significant public health threat for several decades to come.

  3. The effects of seasonal, ontogenetic, and genetic factors on lifespan of male and female progeny of Arvicola amphibius

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    Galina eNazarova


    Full Text Available The water vole (Arvicola amphibius in the forest-steppe of West Siberia is known to have wide fluctuations in abundance. These fluctuations are accompanied by changes in birth and death rates, sex-age structure of the population, and individual morphophysiological and behavioral characteristics of the animals. Survival of the animals depends on season, phase of population cycle, and sex. Based on the data of long-term captive breeding of water voles, the maximal lifespan of males was found to be 1188 days and that of females, 1108 days. There were no differences between the sexes in mean lifespan. The probability of living 2 years or longer was 0.21. Individuals who began breeding at an older age had a significantly longer lifespan and produced more offspring. The survival curves of the spring-born animals were steeper than of those summer/autumn-born. Maternal factors had differential effect on males and females with respect to lifespan. Male lifespan correlated negatively with maternal age, parity, and litter size, whereas female lifespan did not correlate with these characteristics. To estimate heritability, parent-offspring correlations of a lifespan were calculated, as well as full-sib intraclass correlations. No statistically significant correlation was found between sons’ and maternal, sons’ and paternal, and daughters’ and paternal lifespans. Daughters’ lifespan correlated positively with maternal lifespan (r = 0.21, p < 0.001. Female full-sibs and male full-sibs had the same intraclass correlations, 0.22, p < 0.001. The differences between heritability estimates obtained by different methods may be explained by sex-specific genetic controls over lifespan and/or sex-specific effects of the environment.

  4. Estrogen receptors in the medial amygdala inhibit the expression of male prosocial behavior. (United States)

    Cushing, Bruce S; Perry, Adam; Musatov, Sergei; Ogawa, Sonoko; Papademetriou, Eros


    Studies using estrogen receptor alpha (ERalpha) knock-out mice indicate that ERalpha masculinizes male behavior. Recent studies of ERalpha and male prosocial behavior have shown an inverse relationship between ERalpha expression in regions of the brain that regulate social behavior, including the medial amygdala (MeA), and the expression of male prosocial behavior. These studies have lead to the hypothesis that low levels of ERalpha are necessary to "permit" the expression of high levels of male prosocial behavior. To test this, viral vectors were used to enhance ERalpha in male prairie voles (Microtus ochrogaster), which display high levels of prosocial behavior and low levels of MeA ERalpha. Adult male prairie voles were transfected with ERalpha in the MeA (MeA-ERalpha) or the caudate-putamen (ERalpha control) or luciferase (MeA-site-specific control), and 3 weeks later tested for spontaneous alloparental behavior and partner preference. Enhancing ERalpha in the MeA altered/reduced male prosocial behavior. Only one-third of MeA-ERalpha males, compared with all control males, were alloparental. MeA-ERalpha males also displayed a significant preference for a novel female. This is a critical finding because the manipulations of neuropeptides, oxytocin and vasopressin, can inhibit the formation of a partner preference, but do not lead to the formation of a preference for a novel female. The results support the hypothesis that low levels of ERalpha are necessary for high levels of male prosocial behavior, and provide the first direct evidence that site-specific ERalpha expression plays a critical role in the expression of male prosocial behavior.

  5. Energetic dose: Beyond fire and flint? (United States)

    Linder, G.; Rattner, B.; Cohen, J.


    Nutritional and bioenergetic interactions influence exposure to environmental chemicals and may affect the risk realized when wildlife are exposed in the field. Here, food-chain analysis focuses on prairie voles (Microtus ochrogaster) and the evaluation of chemical risks associated with paraquat following 10-d dietary exposures. Reproductive effects were measured in 60-d trials that followed exposures to paraquat-tainted feed: control (untainted feed); 21 mg paraquat/kg feed; 63 mg paraquat/kg feed; and feed-restricted control (untainted feed restricted to 60% baseline consumption). Reproductive success was evaluated in control and treated breeding pairs, and a preliminary bioenergetics analysis was completed in parallel to derive exposure dose. Although reproductive performance differed among groups, feed-restriction appeared to be the dominant treatment effect observed in these 10-d feeding exposure/limited reproductive trials. Exposure dose ranged from 3.70-3.76 to 9.41-11.51 mg parquat/kg BW/day at 21 and 63 mg paraquat/kg feed stock exposures, respectively. Energetic doses as ug paraquat/kcal yielded preliminary estimates of energetic costs associated with paraquat exposure, and were similar within treatments for both sexes, ranging from 4.2-5.5 and 13.1-15.0 ug paraquat/kcal for voles exposed to 21 mg/kg feed stock and 63 mg/kg feed stock, respectively. Given the increasing likelihood that environmental chemicals will be found in wildlife habitat at 'acceptable levels', the critical role that wildlife nutrition plays in evaluating ecological risks should be fully integrated into the assessment process. Tools applied to the analysis of risk must gain higher resolution than the relatively crude methods we currently bring to the process.

  6. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada.

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    Justin S Strong

    Full Text Available The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator. This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland.

  7. Three-dimensional reconstruction techniques to study ditches eco-hydrology (United States)

    Vinatier, Fabrice; Bailly, Jean-Stéphane; Combemale, David


    Agricultural ditches are common linear features of cultivated landscapes assuming several primary functions: soil water drainage, retention of pollutants, soil erosion prevention. In Mediterranean hilly areas, ditches shape a network over a catchment in order to convey surface runoff out of the plots during short but intense storms. Furthermore, these man made ditches provide valuable habitat for fauna and flora. Our study aims at exploring how the hydraulic functioning of ditches is affected by biotic activities occurring at ditch scale, such as plant development (canopy height, vegetation covering and blockage factor which is the fraction of the channel cross-section blocked by vegetation, which all determines the flow resistance due to vegetation) and soil disturbance by burrowing herbivores. To this end, we applied a stereophotogrammetric study to monitor vegetation and ditch geometry on a 100 meters long ditch segment. The study was conducted from April to December 2014 on an agricultural ditch in South of France. Plant species were collected for referencing and manifestation of soil disturbance by Mediterranean Pine Vole were noticed. The data collected gathered a chronosequence of twenty point clouds at 1 mm resolution. Clouds coherence and precision were confronted to Terrestrial Lidar Scans acquired in April and September 2014 for validation. Clouds were classified to disentangle the ground from the canopy vegetation . The Pine Vole excavations and the plant species were classified inside the ground and vegetation clouds, respectively. Different vegetation metrics related to ditch hydraulics were estimated and map from the chronosequence : the canopy height dynamics, the vegetation cover dynamics and the blockage factors dynamic.. Vegetation metrics appears to be highly variable temporally and spatially, mainly due to plant development and species traits. Thanks to these three-dimensional reconstruction techniques, data clouds at high resolution linked to

  8. Late Quaternary environments and biogeography in the Great Basin (United States)

    Thompson, R. S.; Mead, J. I.


    Plant and animal remains found in packrat ( Neotoma spp.) middens and cave fill from the eastern and southern Great Basin region reveal the presence of subalpine conifers and boreal mammals at relatively low elevations during the Late Wisconsin. Limber pine ( Pinus flexilis) and bristlecone pine ( P. longaeva) were important in the late Pleistocene plant communities throughout this region. Spruce ( Picea cf. engelmannii) and common juniper ( Juniperus communis) were present in some of the more northerly localities, and Douglas fir ( Pseudotsuga menziesii) and white fir ( Abies concolor) were present in southern and eastern localities. Single needle pinyon pine ( Pinus monophylla), common across this region today, was apparently not present north of the Sheep Range of southern Nevada during the Late Wisconsin. Pikas ( Ochotona cf. princeps), small boreal mammals present in only a few Great Basin mountain ranges today, were common throughout the region. Heather voles ( Phenacomys cf. intermedius) have been found in two cave fill deposits in Nevada, though they are unknown in the Great Basin today. Limber and bristlecone pines are generally restricted to rocky substrates in modern subalpine habitats in the Great Basin, and this may also have been the case when these plants grew at lower elevations during the Late Wisconsin. Subalpine conifers were present on the rock outcrops sampled by the packrat middens, but shrub communities, perhaps dominated by sagebrush ( Artemisia spp.), may have been present on alluvial valley-bottom substrates. Forested habitats would thus have been isolated habitat islands, as they are today. Boreal small mammals, including pikas and heather voles, were able to colonize the Great Basin mountain ranges during the late Pleistocene. We suggest that these mammals were able to survive in the intervening valley-bottoms under a cool-summer climatic regime, and that continuous forest or woodland corridors were not necessary for migration.

  9. Neural Regulation of Pair Bond Formation in a Monogamous Rodent Species%单配制啮齿动物Pair Bond形成的神经调节机制

    Institute of Scientific and Technical Information of China (English)

    Brandon J.Aragona; J.Thomas Curtis; 刘彦; 汪作新


    单配制啮齿动物社会结构的神经生物学原理可以通过实验室研究Social bonding而获得.在本文中,我们探讨了如何利用单配制的草原田鼠(Microtus ochrogaster)作为研究模型揭示pair bond形成的神经调控机制.我们进而探讨了单配制与多配制田鼠之间神经解剖学的差异以及神经化学物质的调节是怎样影响pair bond的.本篇综述还讨论了与pair bond形成有关的神经化学系统之间的相互影响以及pair bond形成过程中的两性差异.最后,我们预测了这一研究领域的未来研究方向以及研究social bonding的神经调控对人类健康的重要性.%The neurobiology of monogamous social organization can be studied by laboratory examination of social bonding. In this review, we discuss how the monogamous prairie vole (Microtus ochrogaster) has been used as a model system to provide tremendous insight into the neural regulation of pair bond formation. Neuroanatomical differences between monogamous and non-monogamous voles, as well as how neurochemical manipulations affect pair bond formation are reviewed. In addition, interactions among neurochemical systems that regulate pair bond formation and the extent of sexual dimorphism associated with pair bonding are discussed. Finally, we propose future directions for this line of research and explain why understanding the neural regulation of social bonding is important for human health.

  10. Ecology and management of rodents in no-till agriculture in Washington, USA. (United States)

    Witmer, Gary; Sayler, Rodney; Huggins, David; Capelli, Jason


    No-till farming is an important approach to sustainable agriculture because it can conserve soil and water resources. Unfortunately, rodent populations can thrive under no-till conditions because burrow systems are not disrupted by annual plowing and plant residues build-up on the surface, providing cover and insulation. This can result in substantial crop damage. We assessed rodent populations, habitat use, food habits, and crop damage in a no-till cropping system in Washington, USA. We also conducted preliminary trials of methods to reduce rodent populations and crop damage. In the fall, many more rodents were captured in fields with unharvested crops than in fields containing only plant stubble, suggesting that rodents leave fields after crop harvest, providing that suitable habitats are nearby, even when adequate cover is still available in harvested crop fields. By spring, the number of voles captured was much lower relative to fall. Despite this, capture rates were much higher in surrounding permanent grass areas than in crop (barley, wheat, pea) fields, suggesting that these grassy areas serve as refugia for rodents. Furthermore, the permanent grass cover type was the landscape variable most associated with rodent capture rates. In three winter pea fields, rodents removed 5-15% of the pea plants over winter. Examination of stomach contents revealed that voles mainly fed on grain plants in spring, but that their diet was more diversified in fall. Deer mice fed heavily on grain plants in both spring and fall, but also used insects as food. Metal barrier exclosures (9 m × 9 m), extending above and below ground, did not prevent access by rodents. Rodent populations in areas treated with zinc phosphide on grain were comparable to untreated areas 1 year after application of the rodenticide, perhaps because of immigration and recruitment, suggesting that baiting does not provide a long-term solution to rodent damage in no-till agricultural fields.

  11. Lack of a distinct gradient in biomarker responses in small mammals collected at different distances from a highway. (United States)

    Hamers, T; Smit, L A M; Bosveld, A T C; van den Berg, J H J; Koeman, J H; van Schooten, F J; Murk, A J


    This study describes biomarker effects in small mammals exposed to traffic emissions. Animals were collected at 10-50 m (site 1), 150-200 m (site 2), and 5 km (site 3) from a very busy highway (A2). To distinguish between routes of exposure, strictly carnivorous common shrews ( Sorex araneus) and predominantly herbivorous bank voles ( Clethrionomys glareolus) were collected. As a measure of exposure to polycyclic aromatic hydrocarbons (PAHs), aromatic DNA adduct levels were determined by (32)P-postlabeling techniques in tissue from heart, lung, and liver. Lead (Pb), cadmium (Cd), and copper (Cu) levels were analyzed in kidney as a measure of exposure to heavy metals. EROD and PROD activity and retinoid levels were determined in liver as effect biomarkers for exposure to PAHs and polyhalogenated aromatic hydrocarbons (PHAHs). Relatively high Cd levels in S. araneus and in particular elevated DNA adduct levels in C. glareolus indicated that small mammals at site 3 were exposed to more compounds than at sites 1 and 2 (3 > or = 1 > 2). The latter effect is probably due to an incidental and actual input of airborne pollutants that is deposited on plant surfaces. By consumption of above-ground vegetation, voles are chronically exposed to this pollution. Relatively high background input of PAHs probably hinders that the traffic-related gradient of airborne PAH concentrations found in an earlier study is reflected in DNA adduct levels in small mammals in the present study. Moreover, historical biomarkers for exposure to traffic emissions, such as increased kidney Pb levels, increased hepatic EROD activity, and disturbed hepatic vitamin A homeostasis are no longer applicable to indicate differences in exposure. This is a result of the ban on addition of Pb and chlorinated scavengers to gasoline and of cleaner combustion techniques, which were enforced by law over the past decade. Finally, it is advisable to use only juvenile small mammals for in situ monitoring of diffuse

  12. Neuroendocrine perspectives on social attachment and love. (United States)

    Carter, C S


    The purpose of this paper is to review existing behavioral and neuroendocrine perspectives on social attachment and love. Both love and social attachments function to facilitate reproduction, provide a sense of safety, and reduce anxiety or stress. Because social attachment is an essential component of love, understanding attachment formation is an important step toward identifying the neurobiological substrates of love. Studies of pair bonding in monogamous rodents, such as prairie voles, and maternal attachment in precocial ungulates offer the most accessible animal models for the study of mechanisms underlying selective social attachments and the propensity to develop social bonds. Parental behavior and sexual behavior, even in the absence of selective social behaviors, are associated with the concept of love; the analysis of reproductive behaviors, which is far more extensive than our understanding of social attachment, also suggests neuroendocrine substrates for love. A review of these literatures reveals a recurrent association between high levels of activity in the hypothalamic pituitary adrenal (HPA) axis and the subsequent expression of social behaviors and attachments. Positive social behaviors, including social bonds, may reduce HPA axis activity, while in some cases negative social interactions can have the opposite effect. Central neuropeptides, and especially oxytocin and vasopressin have been implicated both in social bonding and in the central control of the HPA axis. In prairie voles, which show clear evidence of pair bonds, oxytocin is capable of increasing positive social behaviors and both oxytocin and social interactions reduce activity in the HPA axis. Social interactions and attachment involve endocrine systems capable of decreasing HPA reactivity and modulating the autonomic nervous system, perhaps accounting for health benefits that are attributed to loving relationships.

  13. Genetic variability of Rickettsia spp. in Ixodes persulcatus/Ixodes trianguliceps sympatric areas from Western Siberia, Russia: Identification of a new Candidatus Rickettsia species. (United States)

    Igolkina, Yana P; Rar, Vera A; Yakimenko, Valeriy V; Malkova, Marina G; Tancev, Aleksey K; Tikunov, Artem Yu; Epikhina, Tamara I; Tikunova, Nina V


    Rickettsia spp. are the causative agents of a number of diseases in humans. These bacteria are transmitted by arthropods, including ixodid ticks. DNA of several Rickettsia spp. was identified in Ixodes persulcatus ticks, however, the association of Ixodes trianguliceps ticks with Rickettsia spp. is unknown. In our study, blood samples of small mammals (n=108), unfed adult I. persulcatus ticks (n=136), and I. persulcatus (n=12) and I. trianguliceps (n=34) ticks feeding on voles were collected in two I. persulcatus/I. trianguliceps sympatric areas in Western Siberia. Using nested PCR, ticks and blood samples were studied for the presence of Rickettsia spp. Three distinct Rickettsia species were found in ticks, but no Rickettsia species were found in the blood of examined voles. Candidatus Rickettsia tarasevichiae DNA was detected in 89.7% of unfed I. persulcatus, 91.7% of engorged I. persulcatus and 14.7% of I. trianguliceps ticks. Rickettsia helvetica DNA was detected in 5.9% of I. trianguliceps ticks. In addition, a new Rickettsia genetic variant was found in 32.4% of I. trianguliceps ticks. Sequence analysis of the 16S rRNA, gltA, ompA, оmpB and sca4 genes was performed and, in accordance with genetic criteria, a new Rickettsia genetic variant was classified as a new Candidatus Rickettsia species. We propose to name this species Candidatus Rickettsia uralica, according to the territory where this species was initially identified. Candidatus Rickettsia uralica was found to belong to the spotted fever group. The data obtained in this study leads us to propose that Candidatus Rickettsia uralica is associated with I. trianguliceps ticks.

  14. Prevalence of infection with Rickettsia helvetica in Ixodes ricinus ticks feeding on non-rickettsiemic rodent hosts in sylvatic habitats of west-central Poland. (United States)

    Biernat, Beata; Stańczak, Joanna; Michalik, Jerzy; Sikora, Bożena; Wierzbicka, Anna


    Ixodes ricinus is the most prevalent and widely distributed tick species in European countries and plays a principal role in transmission of a wide range of microbial pathogens. It is also a main vector and reservoir of Rickettsia spp. of the spotted fever group with the infection level ranging in Poland from 1.3% to 11.4%. Nevertheless, little research has been conducted so far to identify reservoir hosts for these pathogens. A survey was undertaken to investigate the presence of Rickettsia spp. in wild small rodents and detached I. ricinus. Rodents, Apodemus flavicollis mice and Myodes glareolus voles were captured in typically sylvatic habitats of west-central Poland. Blood samples and collected ticks were analyzed by conventional, semi-nested and nested PCRs. Rickettsial species were determined by sequence analysis of obtained fragments of gltA and 16S rRNA genes. A total of 2339 immature I. ricinus (mostly larvae) were collected from 158 animals. Proportion of hosts carrying ticks was 84%, being higher for A. flavicollis than for M. glareolus. Rickettsia helvetica, the only species identified, was detected in 8% of 12 nymphs and in at least 10.7% (MIR) of 804 larvae investigated. Prevalence of infected ticks on both rodent species was comparable (10.8 vs. 9%). None of blood samples tested was positive for Rickettsia spp. The results showed that in sylvatic habitats the level of infestation with larval I. ricinus was higher in A. flavicollis mice in comparison with M. glareolus voles. They show that R. helvetica frequently occurred in ticks feeding on rodents. Positive immature ticks were collected from non-rickettsiemic hosts what might suggest a vertical route of their infection (transovarial and/or transstadial) or a very short-lasting rickettsiemia in rodents. A natural vertebrate reservoir host for R. helvetica remains to be determined.

  15. Babesia spp. and Anaplasma phagocytophilum in questing ticks, ticks parasitizing rodents and the parasitized rodents – Analyzing the host-pathogen-vector interface in a metropolitan area

    Directory of Open Access Journals (Sweden)

    Silaghi Cornelia


    Full Text Available Abstract Background The aims of this study were to evaluate the host-tick-pathogen interface of Babesia spp. and Anaplasma phagocytophilum in restored areas in both questing and host-attached Ixodes ricinus and Dermacentor reticulatus and their small mammalian hosts. Methods Questing ticks were collected from 5 sites within the city of Leipzig, Germany, in 2009. Small mammals were trapped at 3 of the 5 sites during 2010 and 2011. DNA extracts of questing and host-attached I. ricinus and D. reticulatus and of several tissue types of small mammals (the majority bank voles and yellow-necked mice, were investigated by PCR followed by sequencing for the occurrence of DNA of Babesia spp. and by real-time PCR for A. phagocytophilum. A selected number of samples positive for A. phagocytophilum were further investigated for variants of the partial 16S rRNA gene. Co-infection with Rickettsia spp. in the questing ticks was additionally investigated. Results 4.1% of questing I. ricinus ticks, but no D. reticulatus, were positive for Babesia sp. and 8.7% of I. ricinus for A. phagocytophilum. Sequencing revealed B. microti, B. capreoli and Babesia spp. EU1 in Leipzig and sequence analysis of the partial 16S RNA gene of A. phagocytophilum revealed variants either rarely reported in human cases or associated with cervid hosts. The statistical analysis revealed significantly less ticks infected with A. phagocytophilum in a city park in Leipzig as compared to the other sampling sites. A. phagocytophilum-DNA was detected in 2 bank voles, DNA of B. microti in 1 striped field-mouse and of Babesia sp. EU1 in the skin tissue of a mole. Co-infections were detected. Conclusion Our results show the involvement of small mammals in the natural endemic cycles of tick-borne pathogens. A more thorough understanding of the interactions of ticks, pathogens and hosts is the essential basis for effective preventive control measures.

  16. Using a data-constrained model of home range establishment to predict abundance in spatially heterogeneous habitats.

    Directory of Open Access Journals (Sweden)

    Mark C Vanderwel

    Full Text Available Mechanistic modelling approaches that explicitly translate from individual-scale resource selection to the distribution and abundance of a larger population may be better suited to predicting responses to spatially heterogeneous habitat alteration than commonly-used regression models. We developed an individual-based model of home range establishment that, given a mapped distribution of local habitat values, estimates species abundance by simulating the number and position of viable home ranges that can be maintained across a spatially heterogeneous area. We estimated parameters for this model from data on red-backed vole (Myodes gapperi abundances in 31 boreal forest sites in Ontario, Canada. The home range model had considerably more support from these data than both non-spatial regression models based on the same original habitat variables and a mean-abundance null model. It had nearly equivalent support to a non-spatial regression model that, like the home range model, scaled an aggregate measure of habitat value from local associations with habitat resources. The home range and habitat-value regression models gave similar predictions for vole abundance under simulations of light- and moderate-intensity partial forest harvesting, but the home range model predicted lower abundances than the regression model under high-intensity disturbance. Empirical regression-based approaches for predicting species abundance may overlook processes that affect habitat use by individuals, and often extrapolate poorly to novel habitat conditions. Mechanistic home range models that can be parameterized against abundance data from different habitats permit appropriate scaling from individual- to population-level habitat relationships, and can potentially provide better insights into responses to disturbance.

  17. Losing ground: past history and future fate of Arctic small mammals in a changing climate. (United States)

    Prost, Stefan; Guralnick, Robert P; Waltari, Eric; Fedorov, Vadim B; Kuzmina, Elena; Smirnov, Nickolay; van Kolfschoten, Thijs; Hofreiter, Michael; Vrieling, Klaas


    According to the IPCC, the global average temperature is likely to increase by 1.4-5.8 °C over the period from 1990 to 2100. In Polar regions, the magnitude of such climatic changes is even larger than in temperate and tropical biomes. This amplified response is particularly worrisome given that the so-far moderate warming is already impacting Arctic ecosystems. Predicting species responses to rapid warming in the near future can be informed by investigating past responses, as, like the rest of the planet, the Arctic experienced recurrent cycles of temperature increase and decrease (glacial-interglacial changes) in the past. In this study, we compare the response of two important prey species of the Arctic ecosystem, the collared lemming and the narrow-skulled vole, to Late Quaternary climate change. Using ancient DNA and Ecological Niche Modeling (ENM), we show that the two species, which occupy similar, but not identical ecological niches, show markedly different responses to climatic and environmental changes within broadly similar habitats. We empirically demonstrate, utilizing coalescent model-testing approaches, that collared lemming populations decreased substantially after the Last Glacial Maximum; a result consistent with distributional loss over the same period based on ENM results. Given this strong association, we projected the current niche onto future climate conditions based on IPCC 4.0 scenarios, and forecast accelerating loss of habitat along southern range boundaries with likely associated demographic consequences. Narrow-skulled vole distribution and demography, by contrast, was only moderately impacted by past climatic changes, but predicted future changes may begin to affect their current western range boundaries. Our work, founded on multiple lines of evidence suggests a future of rapidly geographically shifting Arctic small mammal prey communities, some of whom are on the edge of existence, and whose fate may have ramifications for the

  18. Abundance of wild rodents, ticks and environmental risk of Lyme borreliosis: a longitudinal study in an area of Mazury Lakes district of Poland. (United States)

    Siński, Edward; Pawełczyk, Agnieszka; Bajer, Anna; Behnke, Jerzy


    The results of a longitudinal epidemiological survey in two contrasting habitats in an area of the Mazury Lakes district of Poland indicate that both host and vector (Ixodes ricinus) densities, may be the most important risk factors for the tick-transmitted spirochetes of Borrelia burgdirferi s.l. However, the results also highlight that even related host species, such as the wild rodents Apodemus flavicollis and Clethrionomys glareolus that share the same habitat, can show quite different dynamics of tick infestation. We provide evidence that the woodland populations of A. flavicollis and C. glareolus are more frequently infested with larvae than nymphs, and more frequently with both stages than M. arvalis in the neighbouring open fallow lands. The prevalence of infestation with larvae varied from 92 % for A. flavicollis, and 76 % for C. glareolus to 37 % for M. arvalis. Other factors, such as population age structure and sex, were also shown to impact on tick densities on hosts at particular times of the year and hence on the zoonotic risk. Moreover, particular species of rodents from different habitats, A. flavicollis (woodlands) and Microtus arvalis (fallow lands) carry infected immature I. ricinus ticks more frequently than C. glareolus voles (woodlands). Thus, the relative contribution of each species to the cumulative reservoir competence differs among species living in the woodland habitats and in relation to voles living in the fallow lands. It follows, therefore, that any factor which reduces the relative density of A. flavicollis in comparison to other hosts in the wild rodent community, will reduce also the risk of human exposure to Lyme borreliosis spirochetes.

  19. Entre la indignación y la interpretación lúdica: el diálogo intergeneracional ante el falso documental Operación Palace

    Directory of Open Access Journals (Sweden)

    Marta Montagut


    Full Text Available La emisión del falso documental Operación Palace acerca del intento de golpe de 1981, dirigido por el periodista Jordi Évole, generó un aluvión de reacciones altamente polarizadas entre actores políticos, académicos y periodísticos. Este artículo analiza las opiniones publicadas en El Mundo, El País, Ara y La Vanguardia. Así, observamos que las voces de los testigos directos del golpe son más proclives a considerar el programa como un mal ejercicio periodístico de banalización histórica, mientras que las voces de segunda generación son más capaces de valorar su dimensión crítica con respecto a la falta de transparencia del golpe de estado y con respecto al lenguaje de los medios audiovisuales.Palabras clave: falso documental, 23F, memoria directa, memoria de 2ª generación, posmemoria, frame, periodismo, formatos audiovisuales._______________Abstract: The broadcast of the faux documentary Operación Palace (Operation Palace about the attempted coup in 1981, directed by journalist Jordi Évole, generated a flood of highly polar reactions among politicians, academics and journalists. In this article we analyze the opinions published in El Mundo, El País, Ara and La Vanguardia. Consequently, we observed that the voices of the direct witnesses of the coup are more inclined to consider the program a bad journalistic exercise in historic trivialization, while second generation voices are more capable of valuing its critical dimension with regards to the lack of transparency in the coup d’etat and the language of the audiovisual media.Keywords: mockumentary, 23F, direct memory, 2nd generation memory, postmemory, frame, journalism, audiovisual formats.

  20. Small mammal community succession on the beach of Dongting Lake, China after the Three Gorges Project. (United States)

    Zhang, Meiwen; Wang, Yong; Li, Bo; Guo, Cong; Huang, Guoxian; Shen, Guo; Zhou, Xunjun


    Although the Three Gorges Project (TGP) may have affected the population structure and distribution of plant and animal communities, few studies have analyzed the effect of this project on small mammal communities. Therefore, the present paper compares the small mammal communities inhabiting the beaches of Dongting Lake using field investigations spanning a 20-year period, both before and after the TGP was implemented. Snap traps were used throughout the census. The results indicate that the TGP caused major changes to the structure of the small mammal community at a lake downstream of the dam. First, species abundance on the beaches increased after the project commenced. The striped field mouse (Apodemus agrarius) and the Norway rat (Rattus norvegicus), which rarely inhabited the beach before the TGP, became abundant (with marked population growth) once water was impounded by the Three Gorges Reservoir. Second, dominant species concentration indices exhibited a stepwise decline, indicating that the community structure changed from a single dominant species to a more diverse species mix after TGP implementation. Third, the regulation of water discharge release by the TGP might have caused an increase in the species diversity of the animal community on the beaches. A significant difference in diversity indices was obtained before and after the TGP operation. Similarity indices also indicate a gradual increase in species numbers. Hence, a long-term project should be established to monitor the population fluctuations of the Yangtze vole (Microtus fortis), the striped field mouse and the Norway rat to safeguard against population outbreaks (similar to the Yangtze vole outbreak in 2007), which could cause crop damage to adjacent farmland, in addition to documenting the succession process of the small mammal community inhabiting the beaches of Dongting Lake. © 2013 International Society of Zoological Sciences, Institute of Zoology/Chinese Academy of Sciences and Wiley

  1. Impact of non-native terrestrial mammals on the structure of the terrestrial mammal food web of Newfoundland, Canada. (United States)

    Strong, Justin S; Leroux, Shawn J


    The island of Newfoundland is unique because it has as many non-native terrestrial mammals as native ones. The impacts of non-native species on native flora and fauna can be profound and invasive species have been identified as one of the primary drivers of species extinction. Few studies, however, have investigated the effects of a non-native species assemblage on community and ecosystem properties. We reviewed the literature to build the first terrestrial mammal food web for the island of Newfoundland and then used network analyses to investigate how the timing of introductions and trophic position of non-native species has affected the structure of the terrestrial mammal food web in Newfoundland. The first non-native mammals (house mouse and brown rat) became established in Newfoundland with human settlement in the late 15th and early 16th centuries. Coyotes and southern red-backed voles are the most recent mammals to establish themselves on the island in 1985 and 1998, respectively. The fraction of intermediate species increased with the addition of non-native mammals over time whereas the fraction of basal and top species declined over time. This increase in intermediate species mediated by non-native species arrivals led to an overall increase in the terrestrial mammal food web connectance and generality (i.e. mean number of prey per predator). This diverse prey base and sources of carrion may have facilitated the natural establishment of coyotes on the island. Also, there is some evidence that the introduction of non-native prey species such as the southern red-backed vole has contributed to the recovery of the threatened American marten. Long-term monitoring of the food web is required to understand and predict the impacts of the diverse novel interactions that are developing in the terrestrial mammal food web of Newfoundland.

  2. Variation and Evolution of the Meiotic Requirement for Crossing Over in Mammals. (United States)

    Dumont, Beth L


    The segregation of homologous chromosomes at the first meiotic division is dependent on the presence of at least one well-positioned crossover per chromosome. In some mammalian species, however, the genomic distribution of crossovers is consistent with a more stringent baseline requirement of one crossover per chromosome arm. Given that the meiotic requirement for crossing over defines the minimum frequency of recombination necessary for the production of viable gametes, determining the chromosomal scale of this constraint is essential for defining crossover profiles predisposed to aneuploidy and understanding the parameters that shape patterns of recombination rate evolution across species. Here, I use cytogenetic methods for in situ imaging of crossovers in karyotypically diverse house mice (Mus musculus domesticus) and voles (genus Microtus) to test how chromosome number and configuration constrain the distribution of crossovers in a genome. I show that the global distribution of crossovers in house mice is thresholded by a minimum of one crossover per chromosome arm, whereas the crossover landscape in voles is defined by a more relaxed requirement of one crossover per chromosome. I extend these findings in an evolutionary metaanalysis of published recombination and karyotype data for 112 mammalian species and demonstrate that the physical scale of the genomic crossover distribution has undergone multiple independent shifts from one crossover per chromosome arm to one per chromosome during mammalian evolution. Together, these results indicate that the chromosomal scale constraint on crossover rates is itself a trait that evolves among species, a finding that casts light on an important source of crossover rate variation in mammals. Copyright © 2017 by the Genetics Society of America.

  3. Effects of the mitochondria-targeted antioxidant SkQ1 on lifespan of rodents (United States)

    Anisimov, Vladimir N.; Egorov, Maxim V.; Krasilshchikova, Marina S.; Lyamzaev, Konstantin G.; Manskikh, Vasily N.; Moshkin, Mikhail P.; Novikov, Evgeny A.; Popovich, Irina G.; Rogovin, Konstantin A.; Shabalina, Irina G.; Shekarova, Olga N.; Skulachev, Maxim V.; Titova, Tatiana V.; Vygodin, Vladimir A.; Vyssokikh, Mikhail Yu.; Yurova, Maria N.; Zabezhinsky, Mark A.; Skulachev, Vladimir P.


    The effect of the mitochondria-targeted, plastoquinone-containing antioxidant SkQ1 on the lifespan of outbred mice and of three strains of inbred mice was studied. To this end, low pathogen (LP) or specific pathogen free (SPF) vivaria in St. Petersburg, Moscow, and Stockholm were used. For comparison, we also studied mole-voles and dwarf hamsters, two wild species of small rodents kept under simulated natural conditions. It was found that substitution of a LP vivarium for a conventional (non-LP) one doubled the lifespan of female outbred mice, just as SkQ1 did in a non-LP vivarium. SkQ1 prevented age-dependent disappearance of estrous cycles of outbred mice in both LP and non-LP vivaria. In the SPF vivarium in Moscow, male BALB/c mice had shorter lifespan than females, and SkQ1 increased their lifespan to the values of the females. In the females, SkQ1 retarded development of such trait of aging as heart mass increase. Male C57Bl/6 mice housed individually in the SPF vivarium in Stockholm lived as long as females. SkQ1 increased the male lifespan, the longevity of the females being unchanged. SkQ1 did not change food intake by these mice. Dwarf hamsters and mole-voles kept in outdoor cages or under simulated natural conditions lived longer if treated with SkQ1. The effect of SkQ1 on longevity of females is assumed to mainly be due to retardation of the age-linked decline of the immune system. For males under LP or SPF conditions, SkQ1 increased the lifespan, affecting also some other system(s) responsible for aging. PMID:22166671

  4. An analysis of living environment of late Cretaceous pterosaur and birds in Linhai national geopark%临海国家地质公园晚白垩世翼龙及鸟类生存环境分析∗

    Institute of Scientific and Technical Information of China (English)

    张岩; 齐岩辛


    Specimens of the pterosaur Zhej iangopterus linhaiensis and the birdYandangornis longicau-dus are found from upper Cretaceous strata in the Xiaoxiong basin in eastern Zhejiang Province.Having comprehensively analyzed these paleovertebrates’ossatures,occurrences and ecological behavior,com-bined with paleobotany,sporopollen assemblages,sedimentary,lithofacies,palaeogeographical and palae-oecological environments,as well as geologic background of their locality,it is considered that the Xiaox-iong basin inherited geological tectonic framework in Yongkang period during late period of early Creta-ceous,remnants of lakes and marshes spreaded all over the region,in where pterosaurs and birds living and multiplying during the early Xiaoxiong period of late Cretaceous.With intermittent volcanic erup-tions,pyroclastic material accumulating and dry hot climate,lakes and marshes shrank,the ecological en-vironmental degradation caused mass mortality of pterosaurs and birds.In mid-late Xiaoxiong period,a se-ries of large-scale acidic magmatic erupted and volcanic cinder piled,laying the foundations for evolution of rhyolite landform in Linhai national geopark.%临海浙江翼龙及长尾雁荡鸟化石赋存于浙东小雄盆地晚白垩世形成的地层中。通过对比化石骨骼结构及生态习性,结合对地质背景、古地理、古生态环境及化石产地剖面岩性岩相、沉积构造、化石赋存状态、古植物及孢粉组合等研究认为:小雄盆地继承了早白垩世晚期永康期陆相盆地的构造格局,晚白垩世小雄早期,盆地间分布众多残存的湖泊沼泽,它们是翼龙类和鸟类最后的栖息地。受间歇性火山喷发影响,空落相火山碎屑物导致的湖泊萎缩及沼泽化、水体酸化、气候干热等是造成生活在湖泊沼泽周边和翱翔于天空中的翼龙及鸟类集群死亡的主要因素。小雄中晚期,浙东地区经历了较大规模的酸性岩浆喷溢及火山喷发

  5. New Advances in Study of Animal Behavior(Ⅲ): Neurobiological Underpinning of Behavior%动物行为研究新进展(三):动物行为的神经生物学基础

    Institute of Scientific and Technical Information of China (English)



    近年来动物行为学家从神经生物学的角度研究了普通田鼠的空间学习能力和定向能力,发现雄性田鼠的巢域比雌鼠大,因而比雌鼠有更强的空间定向和导航能力,而且发现多配偶制田鼠雄性个体的脑海马比雌性个体大,而单配偶制田鼠两性个体的脑海马大小没有差异.此外,大脑的颅内皮质和前额皮质对田鼠的空间学习过程也起着重要作用.睡眠是动物行为的一种表现,绿头鸭在睡眠时是睁一只眼闭一只眼,实际上是半个脑在睡眠,半个脑保持清醒状态.这种单半球的睡眠方式能使动物在睡眠中对捕食者作出快速反应.对于一些海洋哺乳动物来说,这种睡眠方式则能使动物在睡眠时游到水面进行呼吸换气.动物行为学家已经能够利用脑电图和测脑温技术对动物在睡眠期间的脑动态进行分析,这不仅对动物行为本身的研究开辟了新的前景,而且也揭示了前所未知的大脑活动.%In this paper, we shall examine spatial learning in voles from a neurobiological perspective. Male meadow voles have very large home ranges and have better navigational skills than female. The males in polygamous species would have larger hippocampuses than females, but that no such sex difference in hippocampul size would be seen in monogamous species of voles. Researchers found that the parietal and prefrontal cortex areas of brain also played an important role in the spatial learning process, and in particular that the number of dendritic spines is correlated with learning.Mallards have the ability to sleep with one eye open and the other eye close. In essence, these birds sleep with half of their brain awake and half of their brain asleep. This sleep state allows quick responses to predators, but it does not interfere with the sleep half the birds brain until danger in present. In aquatic mammals like dolphins, whales, fur seals and sea lions, unihemi-spheric sleep is thought to

  6. Microtines: a Model System for Studying the Evolution and Regulation of Social Monogamy%小型田鼠:研究单配制进化与调控的模型

    Institute of Scientific and Technical Information of China (English)

    Bruce S Cushing; Kristin M Kramer


    In mammals monogamy occurs in a form known as social monogamy, which is defined not by sexual exclusivity, but by a suite of characteristics including the formation of long-term pair bonds, biparental care of offspring, incest avoidance, and a lack of sexual dimorphism. In this review we examine the contribution that comparative studies using rodents of the genus Microtus(voles) have made to understanding the evolution of social monogamy and the underlying mechanisms, including the neural circuitry, that regulate the expression of monogamy. Studies with Microtus species support the hypothesis that monogamy may evolve under harsh conditions, while also suggesting that female sexual selection may help to maintain monogamy. The evolution of monogamy in mammals requires an increase in the expression of male prosocial behaviors, such as affiliation, which facilitate pair bond formation and male parental care. The increased expression of prosocial behaviors associated with monogamy are the product of the interaction of neuropeptides, oxytocin (OT) and vasopressin (AVP), and steroids. OT and AVP regulate the expression of pair bonds and parental care and polygynous and monogamous voles express significantly different patterns of OT and V1a (AVP) receptors. While comparative studies have provided insight into the regulation of social monogamy in microtines, the occurrence of intraspecific variation and behavioral plasticity has provided even greater understanding of its regulation. For example, under some conditions polygynous meadow vole (Microtus pennsylvanicus) males display paternal behavior. Despite the fact that they display the V1a receptor pattern associated with polygyny, central administration of vasopressin stimulates the expression of paternal behavior. In the monogamous prairie vole(Microtus ochrogaster), voles from Illinois display high levels of prosocial behavior, while prairie voles from Kansas are much less social and are sexually dimorphic. While the

  7. A new method for the characterization of strain-specific conformational stability of protease-sensitive and protease-resistant PrPSc.

    Directory of Open Access Journals (Sweden)

    Laura Pirisinu

    Full Text Available Although proteinacious in nature, prions exist as strains with specific self-perpetuating biological properties. Prion strains are thought to be associated with different conformers of PrP(Sc, a disease-associated isoform of the host-encoded cellular protein (PrP(C. Molecular strain typing approaches have been developed which rely on the characterization of protease-resistant PrP(Sc. However, PrP(Sc is composed not only of protease-resistant but also of protease-sensitive isoforms. The aim of this work was to develop a protocol for the molecular characterization of both, protease-resistant and protease-sensitive PrP(Sc aggregates. We first set up experimental conditions which allowed the most advantageous separation of PrP(C and PrP(Sc by means of differential centrifugation. The conformational solubility and stability assay (CSSA was then developed by measuring PrP(Sc solubility as a function of increased exposure to GdnHCl. Brain homogenates from voles infected with human and sheep prion isolates were analysed by CSSA and showed strain-specific conformational stabilities, with mean [GdnHCl](1/2 values ranging from 1.6 M for MM2 sCJD to 2.1 for scrapie and to 2.8 M for MM1/MV1 sCJD and E200K gCJD. Interestingly, the rank order of [GdnHCl](1/2 values observed in the human and sheep isolates used as inocula closely matched those found following transmission in voles, being MM1 sCJD the most resistant (3.3 M, followed by sheep scrapie (2.2 M and by MM2 sCJD (1.6 M. In order to test the ability of CSSA to characterise protease-sensitive PrP(Sc, we analysed sheep isolates of Nor98 and compared them to classical scrapie isolates. In Nor98, insoluble PrP(Sc aggregates were mainly protease-sensitive and showed a conformational stability much lower than in classical scrapie. Our results show that CSSA is able to reveal strain-specified PrP(Sc conformational stabilities of protease-resistant and protease-sensitive PrP(Sc and that it is a valuable tool

  8. 50 years of snow stratigraphy observations (United States)

    Johansson, C.; Pohjola, V.; Jonasson, C.; Challagan, T. V.


    With start in autumn 1961 the Abisko Scientific Research Station (ASRS) located in the Swedish sub Arctic has performed snow stratigraphy observations, resulting in a unique 50 year long time series of data. The data set contains grain size, snow layer hardness, grain compactness and snow layer dryness, observed every second week during the winter season. In general snow and snow cover are important factors for the global radiation budget, and the earth's climate. On a more local scale the layered snowpack creates a relatively mild microclimate for Arctic plants and animals, and it also determines the water content of the snowpack (snow water equivalent) important for e.g. hydrological applications. Analysis of the snow stratigraphy data, divided into three consecutive time periods, show that there has been a change in the last time period. The variable most affected is the snow layer hardness, which shows an increase in hardness of the snowpack. The number of observations with a very hard snow layer/ice at ground level increased three-fold between the first two time periods and the last time period. The thickness of the bottom layer in the snowpack is also highly affected. There has been a 60% increase in layers thinner than 10 cm in the last time period, resulting in a mean reduction in the thickness of the bottom layer from 14 cm to 11 cm. Hence the living conditions for plants and animals at the ground surface have been highly changed. The changes in the snowpack are correlated to an increased mean winter air temperature. Thus, continued increasing, or temperatures within the same ranges as in the last time period, is likely to create harder snow condition in the future. These changes are likely to affect animals that live under the snow such as lemmings and voles or animals that graze sub-Arctic vegetation in winter (e.g. reindeer that would potentially require increased supplementary feeding that incurs financial costs to Sami reindeer herders). Any decrease

  9. A Comparison between Transcriptome Sequencing and 16S Metagenomics for Detection of Bacterial Pathogens in Wildlife.

    Directory of Open Access Journals (Sweden)

    Maria Razzauti

    Full Text Available Rodents are major reservoirs of pathogens responsible for numerous zoonotic diseases in humans and livestock. Assessing their microbial diversity at both the individual and population level is crucial for monitoring endemic infections and revealing microbial association patterns within reservoirs. Recently, NGS approaches have been employed to characterize microbial communities of different ecosystems. Yet, their relative efficacy has not been assessed. Here, we compared two NGS approaches, RNA-Sequencing (RNA-Seq and 16S-metagenomics, assessing their ability to survey neglected zoonotic bacteria in rodent populations.We first extracted nucleic acids from the spleens of 190 voles collected in France. RNA extracts were pooled, randomly retro-transcribed, then RNA-Seq was performed using HiSeq. Assembled bacterial sequences were assigned to the closest taxon registered in GenBank. DNA extracts were analyzed via a 16S-metagenomics approach using two sequencers: the 454 GS-FLX and the MiSeq. The V4 region of the gene coding for 16S rRNA was amplified for each sample using barcoded universal primers. Amplicons were multiplexed and processed on the distinct sequencers. The resulting datasets were de-multiplexed, and each read was processed through a pipeline to be taxonomically classified using the Ribosomal Database Project. Altogether, 45 pathogenic bacterial genera were detected. The bacteria identified by RNA-Seq were comparable to those detected by 16S-metagenomics approach processed with MiSeq (16S-MiSeq. In contrast, 21 of these pathogens went unnoticed when the 16S-metagenomics approach was processed via 454-pyrosequencing (16S-454. In addition, the 16S-metagenomics approaches revealed a high level of coinfection in bank voles.We concluded that RNA-Seq and 16S-MiSeq are equally sensitive in detecting bacteria. Although only the 16S-MiSeq method enabled identification of bacteria in each individual reservoir, with subsequent derivation of

  10. Why is tick-borne encephalitis increasing? A review of the key factors causing the increasing incidence of human TBE in Swedena

    Directory of Open Access Journals (Sweden)

    Jaenson Thomas GT


    Full Text Available Abstract The highest annual incidence of human tick-borne encephalitis (TBE in Sweden ever recorded by the Swedish Institute for Communicable Disease Control (SMI occurred last year, 2011. The number of TBE cases recorded during 2012 up to 6th August 2012 indicates that the incidence for 2012 could exceed that of 2011. In this review of the ecology and epidemiology of TBE in Sweden our main aim is to analyse the possible reasons behind the gradually increasing incidence of human TBE during the last 20 years. The main TBE virus (TBEV vector to humans in Sweden is the nymphal stage of the common tick Ixodes ricinus. The main mode of transmission and maintenance of TBEV in the tick population is considered to be when infective nymphs co-feed with uninfected but infectible larvae on rodents. In most locations the roe deer, Capreolus capreolus is the main host for the reproducing adult I. ricinus ticks. The high number of roe deer for more than three decades has resulted in a very large tick population. Deer numbers have, however, gradually declined from the early 1990s to the present. This decline in roe deer numbers most likely made the populations of small rodents, which are reservoir-competent for TBEV, gradually more important as hosts for the immature ticks. Consequently, the abundance of TBEV-infected ticks has increased. Two harsh winters in 2009–2011 caused a more abrupt decline in roe deer numbers. This likely forced a substantial proportion of the “host-seeking” ticks to feed on bank voles (Myodes glareolus, which at that time suddenly had become very numerous, rather than on roe deer. Thus, the bank vole population peak in 2010 most likely caused many tick larvae to feed on reservoir-competent rodents. This presumably resulted in increased transmission of TBEV among ticks and therefore increased the density of infected ticks the following year. The unusually warm, humid weather and the prolonged vegetation period in 2011 permitted

  11. Study on Population Ecology of Small Mammal in an Abandoned Landfill Using Mark and Recapture Method%用标志重捕法研究废弃地小型兽类群落物种组成及种群生态学特征

    Institute of Scientific and Technical Information of China (English)

    艾尼瓦尔·吐米尔; 阿孜古丽·克依木; 马合木提·哈力克


    The purpose of this study is to observe the population ecology of small mammals in an abandoned landfill using mark and recapture method. Eight species were trapped in Longworth and Sherman traps and ear tags while specific data were recorded. These species included 52 common vole Microtus arvalis, 230 house mouse Mus musculus, 103 white toothed shrews Crocidura russula, 24 House rat Rattus rattus, 96 Norway rats Rattus norvegicus, 15 wood mouse Apodemus sylvaticus, 5 Field vole Microtus agrestis, and 1 Pygmy white toothed shrew Suncus etruscus. The cumulative home ranges indicate the animals have separate microhabitats in the field. The population densities, reproductive cycles, and immigrations show possible movement patterns of the animals throughout the grid. The landfill appears to be recovering as it provides a sufficient habitat for breeding.%我们采用标志重捕方法对废弃地小型兽类群落的物种组成及种群生态学特征进行了初步研究.结果表明, 废弃地小型兽类群落由以下八个物种组成:共捕鼠类529只,分别是普通田鼠52只,小家鼠230只, 中麝鼠句103只, 黑家鼠24只, 褐家鼠96只,小林姬鼠15只,田鼠5只和Pygmy中麝鼠句1只,根据活动区大小的分析发现各物种在废弃地具有各自的活动领域和微栖息地.各物种的种群密度,繁殖周期,迁移特征表明,它们在不同的样地之间进行交流. 总的来说,废弃地为不同的小型兽类提供丰富的食物资源和繁殖活动场所,同时有利于小型兽类的隐蔽,减少捕食危险,因此该景观中的小型兽类物种多样性比较大, 已形成比较稳定的鼠类群落.

  12. The Ecology of the Ural Owl at South-Western Border of Its Distribution (Slovenia

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    Al Vrezec


    Full Text Available In Slovenia the Ural Owl (Strix uralensis is on its south-western limit of distribution and belongs to the southern subspecies Strix uralensis macroura. Dark coloured owls are characteristic for this subspecies and represent between 5 to 15% of the population. Slovenian breeding population size is estimated at 400 to 700 pairs. The densities of territories ranges between 0.9 to 13.4 territories per 10 km2, and the highest are reached in mountain forests of southern Dinaric region. In the forests with dominant deciduous trees, e.g. Beech (Fagus sylvatica and Pedinculate Oak (Quercus robur, the breeding densities are significantly higher than in the forests with higher proportion of coniferous trees, e.g. Norway Spruce (Picea abies. The species does not select specific altitude and throughout Slovenia it occurs between 150 and 1600 m a.s.l.  The most of the nest found at natural nest-sites were in tree holes or semi-holes (56% and at the tree stumps (20%. Nest boxes were occupied less frequently in Slovenia with occupancy rate of 29%. At least in mountain regions breeding begins quite late, between 15 March to 21 June. Average clutch size is 3.3 ± 1.0 eggs per nest. About 80% of all nests are successful raising at least one young. The diet shifts significantly between breeding and non-breeding period due to the seasonality in prey availability. According to the biomass the most important prey in breeding period are mice (Muridae, voles (Arvicollidae and mole (Talpa europaea, but in the non-breeding period voles and dormice (Gliridae predominate. Large Fat Dormouse (Glis glis seems to have very important role in the post-breeding period, but not in the breeding period due to its dormancy. As a large forest-dwelling predator the Ural Owl shapes the raptor community in the forest by excluding mezopredator species, as Tawny Owl (Strix aluco, what allows smaller raptors, e.g. Boreal Owl (Aegolius funereus to expend their ranges to lower elevations


    Kim, Kyeong Soon; Inoue, Kai; Kabeya, Hidenori; Sato, Shingo; Takada, Tomoe; Pangjai, Decha; Chiu, Shih-Hui; Fujita, Hiromi; Kawabata, Hiroki; Takada, Nobuhiro; Kariwa, Hiroaki; Maruyama, Soichi


    We collected 641 small mammals belonging to 17 species of Rodentia and four species of Soricomorpha in Japan, Korea, Russia, Taiwan, and Thailand and investigated the prevalence and genetic diversity of Bartonella species. Apodemus (field mice) and Rattus (rats) were the most-common genera captured, making up 56.0% and 23.1% of the total specimens, respectively. Bartonellae were isolated from 54.6% of the collected animals, and the prevalence varied depending on the host species and the country of origin. The isolates were identified to the species level based on gltA and rpoB sequences. Although most Bartonella species were shared by more than two host species, the distribution patterns of Bartonella species clearly differed among the four most-common host genera: Apodemus, Rattus, Myodes (voles), and Suncus (shrews). The predominant Bartonella species were Bartonella grahamii in Apodemus, Bartonella tribocorum in Rattus, B. grahamii and Bartonella taylorii in Myodes, and an unclassified Bartonella sp. in Suncus.

  14. The complete mitochondrial genome of Microtus fortis calamorum (Arvicolinae, Rodentia) and its phylogenetic analysis. (United States)

    Jiang, Xianhuan; Gao, Jun; Ni, Liju; Hu, Jianhua; Li, Kai; Sun, Fengping; Xie, Jianyun; Bo, Xiong; Gao, Chen; Xiao, Junhua; Zhou, Yuxun


    Microtus fortis is a special resource of rodent in China. It is a promising experimental animal model for the study on the mechanism of Schistosome japonicum resistance. The first complete mitochondrial genome sequence for Microtus fortis calamorum, a subspecies of M. fortis (Arvicolinae, Rodentia), was reported in this study. The mitochondrial genome sequence of M. f. calamorum (Genbank: JF261175) showed a typical vertebrate pattern with 13 protein coding genes, 2 ribosomal RNAs, 22 transfer RNAs and one major noncoding region (CR region).The extended termination associated sequences (ETAS-1 and ETAS-2) and conserved sequence block 1 (CSB-1) were found in the CR region. The putative origin of replication for the light strand (O(L)) of M. f. calamorum was 35bp long and showed high conservation in stem and adjacent sequences, but the difference existed in the loop region among three species of genus Microtus. In order to investigate the phylogenetic position of M. f. calamorum, the phylogenetic trees (Maximum likelihood and Bayesian methods) were constructed based on 12 protein-coding genes (except for ND6 gene) on H strand from 16 rodent species. M. f. calamorum was classified into genus Microtus, Arvcicolinae for the highly phylogenetic relationship with Microtus kikuchii (Taiwan vole). Further phylogenetic analysis results based on the cytochrome b gene ranged from M. f. calamorum to one of the subspecies of M. fortis, which formed a sister group of Microtus middendorfii in the genus Microtus.

  15. Inhaled oxytocin amplifies both vicarious reinforcement and self reinforcement in rhesus macaques (Macaca mulatta). (United States)

    Chang, Steve W C; Barter, Joseph W; Ebitz, R Becket; Watson, Karli K; Platt, Michael L


    People attend not only to their own experiences, but also to the experiences of those around them. Such social awareness profoundly influences human behavior by enabling observational learning, as well as by motivating cooperation, charity, empathy, and spite. Oxytocin (OT), a neurosecretory hormone synthesized by hypothalamic neurons in the mammalian brain, can enhance affiliation or boost exclusion in different species in distinct contexts, belying any simple mechanistic neural model. Here we show that inhaled OT penetrates the CNS and subsequently enhances the sensitivity of rhesus macaques to rewards occurring to others as well as themselves. Roughly 2 h after inhaling OT, monkeys increased the frequency of prosocial choices associated with reward to another monkey when the alternative was to reward no one. OT also increased attention to the recipient monkey as well as the time it took to render such a decision. In contrast, within the first 2 h following inhalation, OT increased selfish choices associated with delivery of reward to self over a reward to the other monkey, without affecting attention or decision latency. Despite the differences in species typical social behavior, exogenous, inhaled OT causally promotes social donation behavior in rhesus monkeys, as it does in more egalitarian and monogamous ones, like prairie voles and humans, when there is no perceived cost to self. These findings potentially implicate shared neural mechanisms.

  16. Higher nest predation risk in association with a top predator: mesopredator attraction? (United States)

    Morosinotto, Chiara; Thomson, Robert L; Hänninen, Mikko; Korpimäki, Erkki


    Breeding close to top predators is a widespread reproductive strategy. Breeding animals may gain indirect benefits if proximity to top predators results in a reduction of predation due to suppression of mesopredators. We tested if passerine birds gain protection from mesopredators by nesting within territories of a top predator, the Ural owl (Strix uralensis). We placed nest boxes for pied flycatchers (Ficedula hypoleuca) in Ural owl nest sites and in control sites (currently unoccupied by owls). The nest boxes were designed so that nest predation risk could be altered (experimentally increased) after flycatcher settlement; we considered predation rate as a proxy of mesopredator abundance. Overall, we found higher nest predation rates in treatment than in control sites. Flycatcher laying date did not differ between sites, but smaller clutches were laid in treatment sites compared to controls, suggesting a response to perceived predation risk. Relative nest predation rate varied between years, being higher in owl nest sites in 2 years but similar in another; this variation might be indirectly influenced by vole abundance. Proximity to Ural owl nests might represent a risky habitat for passerines. High predation rates within owl territories could be because small mesopredators that do not directly threaten owl nests are attracted to owl nest sites. This could be explained if some mesopredators use owl territories to gain protection from their own predators, or if top predators and mesopredators independently seek similar habitats.

  17. Birds and bornaviruses. (United States)

    Payne, Susan L; Delnatte, Pauline; Guo, Jianhua; Heatley, J Jill; Tizard, Ian; Smith, Dale A


    In 2008, avian bornaviruses (ABV) were identified as the cause of proventricular dilatation disease (PDD). PDD is a significant condition of captive parrots first identified in the late 1970s. ABV infection has subsequently been shown to be widespread in wild waterfowl across the United States and Canada where the virus infects 10-20% of some populations of ducks, geese and swans. In most cases birds appear to be healthy and unaffected by the presence of the virus; however, infection can also result in severe non-suppurative encephalitis and lesions similar to those seen in parrots with PDD. ABVs are genetically diverse with seven identified genotypes in parrots and one in canaries. A unique goose genotype (ABV-CG) predominates in waterfowl in Canada and the northern United States. ABV appears to be endemic in North American waterfowl, in comparison to what appears to be an emerging disease in parrots. It is not known whether ABV can spread between waterfowl and parrots. The discovery of ABV infection in North American waterfowl suggests that European waterfowl should be evaluated for the presence of ABV, and also as a possible reservoir species for Borna disease virus (BDV), a related neurotropic virus affecting horses and sheep in central Europe. Although investigations have suggested that BDV is likely derived from a wildlife reservoir, for which the shrew and water vole are currently prime candidates, we suggest that the existence of other mammalian and avian reservoirs should not be discounted.

  18. A probabilistic model in cross-sectional studies for identifying interactions between two persistent vector-borne pathogens in reservoir populations.

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    Elise Vaumourin

    Full Text Available BACKGROUND: In natural populations, individuals are infected more often by several pathogens than by just one. In such a context, pathogens can interact. This interaction could modify the probability of infection by subsequent pathogens. Identifying when pathogen associations correspond to biological interactions is a challenge in cross-sectional studies where the sequence of infection cannot be demonstrated. METHODOLOGY/PRINCIPAL FINDINGS: Here we modelled the probability of an individual being infected by one and then another pathogen, using a probabilistic model and maximum likelihood statistics. Our model was developed to apply to cross-sectional data, vector-borne and persistent pathogens, and to take into account confounding factors. Our modelling approach was more powerful than the commonly used Chi-square test of independence. Our model was applied to detect potential interaction between Borrelia afzelii and Bartonella spp. that infected a bank vole population at 11% and 57% respectively. No interaction was identified. CONCLUSIONS/SIGNIFICANCE: The modelling approach we proposed is powerful and can identify the direction of potential interaction. Such an approach can be adapted to other types of pathogens, such as non-persistents. The model can be used to identify when co-occurrence patterns correspond to pathogen interactions, which will contribute to understanding how organism communities are assembled and structured. In the long term, the model's capacity to better identify pathogen interactions will improve understanding of infectious risk.

  19. Organizational effects of oxytocin on serotonin innervation. (United States)

    Eaton, Jennifer L; Roache, Laura; Nguyen, Khanhbao N; Cushing, Bruce S; Troyer, Emma; Papademetriou, Eros; Raghanti, Mary Ann


    Oxytocin (OT) has an organizational effect within the central nervous system and can have long-lasting effects on the expression of social behavior. OT has recently been implicated in modulating the release of serotonin through activation of receptors in the raphe nuclei. Here we test the hypothesis that OT can have an organizational effect on the serotonergic system. Male prairie voles received an intraperitoneal injection on postnatal day 1 with 3.0 or .3 µg OT, an OT antagonist, or a saline control. Brains were collected on day 21 and immunostained for serotonin. Serotonin axons were quantified in the anterior hypothalamus, cortical amygdala, medial amygdala, paraventricular nucleus of the hypothalamus, and ventromedial hypothalamus. Males treated with 3.0 µg OT displayed significantly higher serotonin axon length densities in the anterior hypothalamus, cortical amygdala, and the ventromedial hypothalamus than control males. These results support the hypothesis that OT has an organizational effect on the serotonin system during the neonatal period, and that these effects are site-specific.

  20. Analysing diet of small herbivores: the efficiency of DNA barcoding coupled with high-throughput pyrosequencing for deciphering the composition of complex plant mixtures

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    Sønstebø Jørn H


    Full Text Available Abstract Background In order to understand the role of herbivores in trophic webs, it is essential to know what they feed on. Diet analysis is, however, a challenge in many small herbivores with a secretive life style. In this paper, we compare novel (high-throughput pyrosequencing DNA barcoding technology for plant mixture with traditional microhistological method. We analysed stomach contents of two ecologically important subarctic vole species, Microtus oeconomus and Myodes rufocanus, with the two methods. DNA barcoding was conducted using the P6-loop of the chloroplast trnL (UAA intron. Results Although the identified plant taxa in the diets matched relatively well between the two methods, DNA barcoding gave by far taxonomically more detailed results. Quantitative comparison of results was difficult, mainly due to low taxonomic resolution of the microhistological method, which also in part explained discrepancies between the methods. Other discrepancies were likely due to biases mostly in the microhistological analysis. Conclusion We conclude that DNA barcoding opens up for new possibilities in the study of plant-herbivore interactions, giving a detailed and relatively unbiased picture of food utilization of herbivores.

  1. Investigating the evolutionary history of the Pacific Northwest mesic forest ecosystem: hypothesis testing within a comparative phylogeographic framework. (United States)

    Carstens, Bryan C; Brunsfeld, Steven J; Demboski, John R; Good, Jeffrey M; Sullivan, Jack


    We examine the evolution of mesic forest ecosystems in the Pacific Northwest of North America using a statistical phylogeography approach in four animal and two plant lineages. Three a priori hypotheses, which explain the disjunction in the mesic forest ecosystem with either recent dispersal or ancient vicariance, are tested with phylogenetic and coalescent methods. We find strong support in three amphibian lineages (Ascaphus spp., and Dicampton spp., and Plethodon vandykei and P. idahoensis) for deep divergence between coastal and inland populations, as predicted by the ancient vicariance hypothesis. Unlike the amphibians, the disjunction in other Pacific Northwest lineages is likely due to recent dispersal along a northern route. Topological and population divergence tests support the northern dispersal hypothesis in the water vole (Microtus richardsoni) and northern dispersal has some support in both the dusky willow (Salix melanopsis) and whitebark pine (Pinus albicaulis). These analyses demonstrate that genetic data sampled from across an ecosystem can provide insight into the evolution of ecological communities and suggest that the advantages of a statistical phylogeographic approach are most pronounced in comparisons across multiple taxa in a particular ecosystem. Genetic patterns in organisms as diverse as willows and salamanders can be used to test general regional hypotheses, providing a consistent metric for comparison among members of an ecosystem with disparate life-history traits.

  2. Survival and growth for pubescent birch, pendula birch and common alder growing on farmland areas; Oeverlevnad och tillvaext hos glasbjoerk, vaartbjoerk och klibbal planterade paa aakermark

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, Tord


    Pendula birches (Betula pendula Roth) and pubescent birches (Betula pubescens Ehrh.) were planted on former farmland. Before planting, the ground was harrowed or the ground was sprayed with terbuthylazine. Tree shelters were used as protection against weeds, voles and wild habitat. Birches treated with terbuthylazine showed the lowest survival. Birches growing in tree shelters were tallest and those growing on spots treated with terbuthylazine were smallest. The diameter at 0.1 m did not differ in a statistically significant way between the treatments. In another experiment with different herbicides, common alder (Alnus glutinosa (L.) Gaertn.) and pendula birch (Betula pendula Roth) were planted on former farmland that had been treated with glyphosate, terbuthylazine and propyzamide or after ground had been harrowed or not treated. In the study on herbicide-treated plants, birch had the highest plant survival. Mostly, species treated with glyphosate were thicker than species treated in other ways. Both species appeared sensitive to terbuthylazine, but not to glyphosate. Birch was not sensitive for propyzamide in opposite to alder. Some practical recommendations concerning afforestation of former farmland, especially weeding, are given.

  3. Role of pet dogs and cats in the transmission of helminthic zoonoses in Europe, with a focus on echinococcosis and toxocarosis. (United States)

    Deplazes, Peter; van Knapen, Frans; Schweiger, Alexander; Overgaauw, Paul A M


    The close emotional tie between people and companion animals is a beneficial relation known as the human-animal bond. However, pet dogs and cats can play an important role in the transmission of helminthic zoonotic agents such as the tapeworms Echinococcus and the roundworms Toxocara which are directly transmitted from pets to the human environment without the involvement of vectors or intermediate hosts. In humans, echinococcosis has emerged in Europe and toxocarosis is still persisting in large endemic areas despite the availability of highly efficient anthelminthics for dogs and cats. Ecological changes significantly contributed to these trends: the high wild fox populations and the high density of freely roaming dogs and cats maintain a permanent infection pressure of these and other parasites. Further, the establishment of urban recreational environments closer to natural ecological systems boosted vole populations that represent urban reservoirs for zoonotic helminths. A good understanding of the parasites' biology and epidemiology including the transmission to humans is required for planning and implementing effective prevention strategies. The continuous education of veterinarians and the information of the pet owners by providing uniform recommendations are of priority importance. A close collaboration between veterinary and public health professionals in a 'One Health' concept is required.

  4. Identification of a New Borrelia Species among Small Mammals in Areas of Northern Spain Where Lyme Disease Is Endemic (United States)

    Gil, Horacio; Barral, Marta; Escudero, Raquel; García-Pérez, Ana L.; Anda, Pedro


    The role of small mammals as reservoir hosts for Borrelia burgdorferi was investigated in several areas where Lyme disease is endemic in northern Spain. A low rate of infestation by Ixodes ricinus nymphs was found in the small mammal populations studied that correlated with the near-absence of B. burgdorferi sensu lato in 184 animals tested and with the lack of transmission of B. burgdorferi sensu lato to I. ricinus larvae that fed on them. In contrast, questing ticks collected at the same time and in the same areas were found to carry a highly variable B. burgdorferi sensu lato repertoire (B. burgdorferi sensu stricto, Borrelia garinii, Borrelia valaisiana, and Borrelia afzelii). Interestingly, the only isolate obtained from small mammals (R57, isolated from a bank vole) grouped by phylogenetic analyses with other Borrelia species but in a separate clade from the Lyme disease and relapsing fever organisms, suggesting that it is a new species. This new agent was widely distributed among small mammals, with infection rates of 8.5 to 12% by PCR. Moreover, a high seroprevalence to B. burgdorferi sensu lato was found in the animal sera, suggesting cross-reactivity between B. burgdorferi sensu lato and R57. Although small mammals do not seem to play an important role as reservoirs for B. burgdorferi sensu lato in the study area, they seem to be implicated in the maintenance of spirochetes similar to R57. PMID:15746336

  5. Albert Camus : colonisateur de bonne volonté ?

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    Bousse Allouche


    Full Text Available Cet article analyse les raisons qui expliquent l'intérêt bénévole qu'Albert Camus avait démontré à l'endroit des Kabyles dans une série de reportages publiés dans Alger Républicain en juin 1939. Malgré une dénonciation franche et sincère de la souffrance dont les Kabyles étaient victimes, les écrits de Camus soulèvent des questions liées à la perception du sujet colonial. La représentation que Camus se faisait des Kabyles était entachée de préjugés et de stéréotypes coloniaux. Le présent article tentera d'établir que le contenu du reportage d'Albert Camus sur les Kabyles évoque à l'esprit l'attitude du colonisateur bienveillant.

  6. Interfon

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    Découvrez nos news sur notre site « News »  Interfon  « News »   Interfon « Au service de nos adhérents »   Interfon est un groupement de fonctionnaires nationaux et internationaux (y compris retraités) de la zone franco-genevoise regroupant plus de 6 000 adhérents. Mise en place avec le statut de « Coopérative » créée dans les années 60, elle a pour mission d’informer, de recommander et de faire bénéficier à ses sociétaires, d’un certain nombre de services et de prix préférentiels auprès de plus de 80 entreprises de la région. Gérée par des administrateurs bénévoles. Interfon s’est développée...


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    Full Text Available Baranica is a cave in the Balkan mountain range in the eastern part of Serbia. It contains four layers of sediments of Quaternary age. The Upper Pleistocene deposits (layers 2-4 have yielded a rich and diverse assemblage of vertebrate fauna, including fish, amphibians, reptiles, birds, and small and large mammals. In this work, preliminary results of a study of the rodent fauna from the Upper Pleistocene deposits of the Baranica Cave (Knjazevac, eastern Serbia are presented. The fossil material comes from the 1995 archaeological excavation. The remains of 10 rodent species are described herein: Spermophilus cf. citelloides, Castor fiber, Sicista subtilis, Cricetulus migratorius, Cricetus cricetus, Mesocricetus newtoni, Apodemus ex gr. sylvaticus-flavicollis, Spalax leucodon, Dryomys nitedula, and Muscardinus avellanarius. Along with eight vole species, this makes altogether 18 species of rodents found in this locality. Both layers 2 and 4 (layer 3 is very poor in fossils have yielded a rodent fauna typical for the cold periods of the Late Pleistocene on the Balkan Peninsula, with a prevalence of open and steppe inhabitants, but some forest dwellers were also present. The assemblages from these layers are similar, but there are some differences in the composition of the fauna, which may indicate a slight shift towards drier conditions. They have also been compared to rodent associations from some Serbian and Bulgarian localities of the same age and their similarities and differences are discussed. SHORT NOTE-NOTA BREVE

  8. Population synchrony in small-world networks. (United States)

    Ranta, Esa; Fowler, Mike S; Kaitala, Veijo


    Network topography ranges from regular graphs (linkage between nearest neighbours only) via small-world graphs (some random connections between nodes) to completely random graphs. Small-world linkage is seen as a revolutionary architecture for a wide range of social, physical and biological networks, and has been shown to increase synchrony between oscillating subunits. We study small-world topographies in a novel context: dispersal linkage between spatially structured populations across a range of population models. Regular dispersal between population patches interacting with density-dependent renewal provides one ecological explanation for the large-scale synchrony seen in the temporal fluctuations of many species, for example, lynx populations in North America, voles in Fennoscandia and grouse in the UK. Introducing a small-world dispersal kernel leads to a clear reduction in synchrony with both increasing dispersal rate and small-world dispersal probability across a variety of biological scenarios. Synchrony is also reduced when populations are affected by globally correlated noise. We discuss ecological implications of small-world dispersal in the frame of spatial synchrony in population fluctuations.

  9. Community-level response to different human disturbances and land use of small mammals in two marshland habitat patches in Hungary

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    Horváth G.F.


    Full Text Available Marshlands are important ecosystems that provide valuable habitats for wildlife communities. We investigated the small mammal community-level response to different human disturbances and land use in the Kis-Balaton Landscape Protection Area, which is an endangered marshland ecosystem of Hungary. Land use, conservation management and other human disturbances (burning, mowing together with unfavorable weather conditions have caused the degradation of the original homogeneous sedgy marshland on both sampled areas. We measured the species turnover between the different periods separated by the habitat changes. Our results suggest that populations of the habitat-specialist species of marshland areas (e.g. endangered Hungarian subspecies of root vole are sensitive to the negative effects of environment and human disturbances. The combined effect of human disturbances and the stochastic processes of the environment can cause the disappearance and substitution of character species stabilizing the communities, which in turn leads to the modification of species composition and structure of small mammal assemblages.

  10. Molecular analyses of mitochondrial pseudogenes within the nuclear genome of arvicoline rodents. (United States)

    Triant, Deborah A; DeWoody, J Andrew


    Nuclear sequences of mitochondrial origin (numts) are common among animals and plants. The mechanism(s) by which numts transfer from the mitochondrion to the nucleus is uncertain, but their insertions may be mediated in part by chromosomal repair mechanisms. If so, then lineages where chromosomal rearrangements are common should be good models for the study of numt evolution. Arvicoline rodents are known for their karyotypic plasticity and numt pseudogenes have been discovered in this group. Here, we characterize a 4 kb numt pseudogene in the arvicoline vole Microtus rossiaemeridionalis. This sequence is among the largest numts described for a mammal lacking a completely sequenced genome. It encompasses three protein-coding and six tRNA pseudogenes that span approximately 25% of the entire mammalian mitochondrial genome. It is bordered by a dinucleotide microsatellite repeat and contains four transposable elements within its sequence and flanking regions. To determine the phylogenetic distribution of this numt among the arvicolines, we characterized one of the mitochondrial pseudogenes (cytochrome b) in 21 additional arvicoline species. Average rates of nucleotide substitution in this arvicoline pseudogene are estimated as 2.3 x 10(-8) substitutions/per site/per year. Furthermore, we performed comparative analyses among all species to estimate the age of this mitochondrial transfer at nearly 4 MYA, predating the origin of most arvicolines.

  11. Fitness loss and germline mutations in barn swallows breeding in Chernobyl

    Energy Technology Data Exchange (ETDEWEB)

    Ellegren, Hans; Lindgren, Gabriella; Primmer, C.R. [Swedish Univ. of Agricultural Sciences, Animal Breeding and Genetics Dept., Uppsala (Sweden); Moeller, A.P. [Universite Pierre et Marie Curie. Lab. d`Ecologie, Paris, 75 (France)


    The severe nuclear accident at Chernobyl in 1986 resulted in the worst reported accidental exposure of radioactive material to free-living organisms. Short-term effects on human populations inhabiting polluted areas include increased incidence of thyroid cancer, infant leukaemia, and congenital malformations in newborns. Two recent studies have reported, although with some controversy, that germline mutation rates were increased in humans and voles living close to Chernobyl, but little is known about the viability of the organisms affected. Here we report an increased frequency of partial albinism, a morphological aberration associated with a loss of fitness, among barn swallows, Hirundo rustica, breeding close to Chernobyl. Heretability estimates indicate that mutations causing albinism were at least partly of germline origin. Furthermore, evidence for an increased germline mutation rate was obtained from segregation analysis at two hypervariable microsatellite loci, indicating that mutation events in barn swallows from Chernobyl were two- to tenfold higher than in birds from control areas in Ukraine and Italy. (author).

  12. Developmental integration in a functional unit: deciphering processes from adult dental morphology. (United States)

    Labonne, Gaëlle; Navarro, Nicolas; Laffont, Rémi; Chateau-Smith, Carmela; Montuire, Sophie


    The evolution of mammalian dentition is constrained by functional necessity and by the non-independence of morphological structures. Efficient chewing implies coherent tooth coordination from development to motion, involving covariation patterns (integration) within dental parts. Using geometric morphometrics, we investigate the modular organization of the highly derived vole dentition. Integration patterns between and within the upper and lower molar rows are analyzed to identify potential modules and their origins (functional and developmental). Results support an integrated adult dentition pattern for both developmental and functional aspects. The integration patterns between opposing molar pairs suggest a transient role for the second upper and lower molars during the chewing motion. Upper and lower molar rows form coherent units but the relative integration of molar pairs is in contradiction with existing developmental models. Emphasis on the first three cusps to grow leads to a very different integration pattern, which would be congruent with developmental models. The early developmental architecture of traits is masked by later stages of growth, but may still be deciphered from the adult phenotype, if careful attention is paid to relevant features.

  13. Description of the population structure and genetic diversity of tuberculosis in Estado de México, a low prevalence setting from Mexico. (United States)

    Zenteno-Cuevas, Roberto; Mendoza-Damián, Fabiola; Muñoz, Irving Cansino; Enciso-Moreno, Leonor; Pérez-Navarro, Lucia Monserrat; Ramírez-Hernández, Ma Dolores; Vázquez-Medina, Karen; Widrobo-García, Lorena; Lauzardo, Michael; Enciso-Moreno, José Antonio


    In order to identify the genetic characteristics of the strains of mycobacteria circulating in the Estado de México, one of the states with the lowest prevalence of tuberculosis in Mexico, spoligotyping and 12-loci MIRU-VNTR typing were used to genotype tuberculosis clinical isolates. The average age of the 183 patients analyzed was 50 (± 17) years, drug resistance was noted in 57 (31%) and multidrug resistance in 22 (12%) individuals. The results from the isolates recovered showed that 80% were located in four major Euro-American lineages: Haarlem (17%), LAM (15%), T (20%) and X (29%). Other lineages found in lower proportions were: EAI, S, Beijing, West African, Turkey, Vole and Bovis. Eighteen isolates were orphans. Only 57 isolates were grouped in nine clusters and the SIT119 (X1) showed the highest number of members (23). The LAM lineage showed an increased risk for development of drug resistance (RR=4, IC: 95%: 1.05-14.2, p = 0.03). Despite the important prevalence of four major lineages found and the diversity of strains circulating in the population, we found the presence of one of the largest populations of isolates clustered to the X lineage in a setting from a Latin American country.

  14. Do multiple herbivores maintain chemical diversity of Scots pine monoterpenes? (United States)

    Iason, Glenn R; O'Reilly-Wapstra, Julianne M; Brewer, Mark J; Summers, Ron W; Moore, Ben D


    A central issue in our understanding of the evolution of the diversity of plant secondary metabolites (PSMs) is whether or not compounds are functional, conferring an advantage to the plant, or non-functional. We examine the hypothesis that the diversity of monoterpene PSMs within a plant species (Scots pine Pinus sylvestris) may be explained by different compounds acting as defences against high-impact herbivores operating at different life stages. We also hypothesize that pairwise coevolution, with uncorrelated interactions, is more likely to result in greater PSM diversity, than diffuse coevolution. We tested whether up to 13 different monoterpenes in Scots pine were inhibitory to herbivory by slugs (Arion ater), bank voles (Clethrionomys glareolus), red deer (Cervus elaphus) and capercaillie (Tetrao urogallus), each of which attack trees at a different life stage. Plants containing more α-pinene were avoided by both slugs and capercaillie, which may act as reinforcing selective agents for this dominant defensive compound. Herbivory by red deer and capercaillie were, respectively, weakly negatively associated with δ(3)-carene, and strongly negatively correlated with the minor compound β-ocimene. Three of the four herbivores are probably contributory selective agents on some of the terpenes, and thus maintain some, but by no means all, of the phytochemical diversity in the species. The correlated defensive function of α-pinene against slugs and capercaillie is consistent with diffuse coevolutionary processes.

  15. A simple, versatile and sensitive cell-based assay for prions from various species.

    Directory of Open Access Journals (Sweden)

    Zaira E Arellano-Anaya

    Full Text Available Detection and quantification of prion infectivity is a crucial step for various fundamental and applied aspects of prion research. Identification of cell lines highly sensitive to prion infection led to the development of cell-based titration procedures aiming at replacing animal bioassays, usually performed in mice or hamsters. However, most of these cell lines are only permissive to mouse-adapted prions strains and do not allow titration of prions from other species. In this study, we show that epithelial RK13, a cell line permissive to mouse and bank vole prion strains and to natural prion agents from sheep and cervids, enables a robust and sensitive detection of mouse and ovine-derived prions. Importantly, the cell culture work is strongly reduced as the RK13 cell assay procedure designed here does not require subcultivation of the inoculated cultures. We also show that prions effectively bind to culture plastic vessel and are quantitatively detected by the cell assay. The possibility to easily quantify a wider range of prions, including rodent experimental strains but also natural agents from sheep and cervids, should prompt the spread of cell assays for routine prion titration and lead to valuable information in fundamental and applied studies.

  16. Experimental infection of chicken embryos with recently described Brucella microti: Pathogenicity and pathological findings. (United States)

    Wareth, Gamal; Böttcher, Denny; Melzer, Falk; Shehata, Awad Ali; Roesler, Uwe; Neubauer, Heinrich; Schoon, Heinz-Adolf


    Brucellae are facultative intracellular pathogens causing disease in a wide range of domestic and wild animals as well as in humans. Brucella (B.) microti is a recently recognized species and was isolated from common voles (Microtus arvalis), red foxes and soil in Austria and the Czech Republic. Its pathogenicity for livestock and its zoonotic potential has not been confirmed yet. In the present study 25 SPF chicken embryos were inoculated at day 11 of age with 1.6×10(3) and 1.6×10(5)B. microti by yolk sac and allantoic sac routes. Re-isolation of B. microti indicated rapid multiplication of bacteria (up to 1.7×10(12)CFU). B. microti provoked marked gross lesions, i.e. hemorrhages and necroses. All inoculated embryos were dead (100% mortality) in between 2nd and 4th day post inoculation. The predominant histopathological lesion was necroses in liver, kidneys, lungs, spleen, gastrointestinal tract, spinal meninges, yolk sac and chorioallantoic membrane. Immunohistochemical examination showed the presence of Brucella antigen in nearly all of these organs, with infection being mainly restricted to non-epithelial cells or tissues. This study provides the first results on the multiplication and pathogenicity of the mouse pathogenic B. microti in chicken embryos. These data suggest that, even though chicken are not mammals, they could provide a useful tool for understanding the pathogenesis of B. microti associated disease.

  17. Bovine tuberculosis infection in wild mammals in the South-West region of England: a survey of prevalence and a semi-quantitative assessment of the relative risks to cattle. (United States)

    Delahay, R J; Smith, G C; Barlow, A M; Walker, N; Harris, A; Clifton-Hadley, R S; Cheeseman, C L


    In the United Kingdom, badgers are implicated in the transmission of Mycobacterium bovis to cattle, but little information is available on the potential role of other wild mammals. This paper presents the results of the largest systematic UK survey of M. bovis infection in other wild mammals. Mammal carcasses (4715) from throughout the South-West region of England were subjected to a systematic post mortem examination, microbiological culture of tissues and spoligotyping of isolates. Infection was confirmed in fox, stoat, polecat, common shrew, yellow-necked mouse, wood mouse, field vole, grey squirrel, roe deer, red deer, fallow deer and muntjac. Prevalence in deer may have been underestimated because the majority were incomplete carcasses, which reduced the likelihood of detecting infection. Infected cases were found in Wiltshire, Somerset, Devon and Cornwall, Gloucestershire and Herefordshire. Lesions were found in a high proportion of spoligotype-positive fallow, red and roe deer, and a single fox, stoat and muntjac. M. bovis spoligotypes occurred in a similar frequency of occurrence to that in cattle and badgers. Data on prevalence, pathology, abundance and ecology of wild mammals was integrated in a semi-quantitative risk assessment of the likelihood of transmission to cattle relative to badgers. Although most species presented a relatively low risk, higher values and uncertainty associated with muntjac, roe, red and in particular fallow deer, suggest they require further investigation. The results suggest that deer should be considered as potential, although probably localised, sources of infection for cattle.

  18. Road network in an agrarian landscape: Potential habitat, corridor or barrier for small mammals? (United States)

    Redon (de), Louis; Le Viol, Isabelle; Jiguet, Frédéric; Machon, Nathalie; Scher, Olivier; Kerbiriou, Christian


    If the negative effects of road networks on biodiversity are now recognized, their role as barriers, habitats or corridors remain to be clarified in human altered landscapes in which road verges often constitute the few semi-natural habitats where a part of biodiversity important for ecosystem functioning may maintain. In human-dominated landscape, their roles are crucial to precise in comparison to other habitats for small mammal species considered as major natural actors (pests (voles) or biological control agents (shrew)). We studied these roles through the comparison of small mammal abundance captured (418 individuals belonging to 8 species) using non-attractive pitfall traps (n = 813) in 176 sampled sites distributed in marginal zones of road and crop, in natural areas and in fields. We examined the effect of roadside width and isolation of sites. We found the higher small mammal abundances in roadside verges and an effect of width margins for shrews. The significant effect of the distance to the next adjacent natural habitat at the same side of the road on the relative abundance of Sorex coronatus, and the absence of a significant effect of distance to the next natural habitat at the opposite side of road, suggest that highway and road verges could be used as corridor for their dispersal, but have also a barrier effect for shrews. Our results show that in intensive agricultural landscapes roadside and highway verges may often serve as refuge, habitat and corridor for small mammals depending on species and margin characteristics.

  19. Characterization of small mammal populations inhabiting the B-C cribs environs

    Energy Technology Data Exchange (ETDEWEB)

    Hedlund, J.D.; Rogers, L.E.


    The purpose of this study was to document the current status of small mammal populations inhibiting the 200 Area plateau near the B-C Crib management area and to compare them with populations inhabiting a protected (control) area within the confines of the Hanford ALE Reserve. Sampling sessions were conducted over two field seasons (1974 and 1975). A total of five species was detected within intensive study areas. These included the Great Basin pocket mouse (Perognathus parvus), deer mouse (Peromyscus maniculatus), northern grasshopper mouse (Onychomys leucogaster), sagebrush vole (Lagurus curtatus), and western harvest mouse (Reithrodontomys megalotis). These species are probably representative of those found throughout the area at this particular elevation. Townsends ground squirrel (Spermophilus townsendii) also occurs in this area but did not occur on the sampling plots during the study duration. The pocket mouse was the only species present in sufficient numbers to permit a detailed analysis of population parameters. A discussion concerning the role small mammals play in mineral cycling and energy transfer processes is included along with a diagram depicting food web interrelationships for consumers inhabiting the 200 Area plateau region. Estimates of small mammal density and biomass provided in this document are needed for an overall understanding of the role biota play in the transfer of waste nuclides.

  20. First detection of Echinococcus multilocularis infection in two species of nonhuman primates raised in a zoo: a fatal case in Cercopithecus diana and a strongly suspected case of spontaneous recovery in Macaca nigra. (United States)

    Yamano, Kimiaki; Kouguchi, Hirokazu; Uraguchi, Kohji; Mukai, Takeshi; Shibata, Chikako; Yamamoto, Hideaki; Takaesu, Noboru; Ito, Masaki; Makino, Yoshinori; Takiguchi, Mitsuyoshi; Yagi, Kinpei


    The causative parasite of alveolar echinococcosis, Echinococcus multilocularis, maintains its life cycle between red foxes (Vulpes vulples, the definitive hosts) and voles (the intermediate hosts) in Hokkaido, Japan. Primates, including humans, and some other mammal species can be infected by the accidental ingestion of eggs in the feces of red foxes. In August 2011, a 6-year-old zoo-raised female Diana monkey (Cercopithecus diana) died from alveolar echinococcosis. E. multilocularis infection was confirmed by histopathological examination and detection of the E. multilocularis DNA by polymerase chain reaction (PCR). A field survey in the zoo showed that fox intrusion was common, and serodiagnosis of various nonhuman primates using western blotting detected a case of a 14-year-old female Celebes crested macaque (Macaca nigra) that was weakly positive for E. multilocularis. Computed tomography revealed only one small calcified lesion (approximately 8mm) in the macaque's liver, and both western blotting and enzyme-linked immunosorbent assay (ELISA) showed a gradual decline of antibody titer. These findings strongly suggest that the animal had recovered spontaneously. Until this study, spontaneous recovery from E. multilocularis infection in a nonhuman primate had never been reported.

  1. Introduzione / Introduction

    Directory of Open Access Journals (Sweden)

    Anna Patullo


    Full Text Available The aim of this article is to show how Bologna City Council is involved in forest fire prevention through control in rural areas and training of the Civil Protection volunteers.Moreover, in 2005, Bologna City Council started a cooperation with the Territorial Informative System (SIT, the Civil Protection, and the National Forestry Commission in order to create a land register for the burnt areas.Cet article a pour objectif de mettre en évidence l'engagement de l'administration municipale de Bologne dans la prévention des incendies de forêts grâce au contrôle du territoire et à la formation des bénévoles de la Protection Civile.En plus, la Mairie de Bologne a entamé depuis 2005 une coopération entre le Système d'Information Territorial (SIT, la Protection Civile et le Corps National des Gardes Forestiers pour créer un cadastre des terrains parcourus par le feu.

  2. Pétanque Club

    CERN Multimedia

    Club de pétanque


    Notre dernier concours interne de la saison challenge Pierre Lecossec du jeudi 29 septembre réunissait onze doublettes sous un temps estival. Cette fois l’honneur revenait aux dames, Sylvie Bosseboeuf et Françoise Vuillier ne pouvaient être départagées et finissaient donc première. Ces deux dames représentent les couleurs du Cern au Championnat Corporatif Genevois. Le 3e est notre précieux juge arbitre en la personne d’Albert Menetrey aussi habile à la pétanque que sur son ordinateur. Merci à Annie et Pierre qui malgré une absence forcée contribuent chaque année aux diverses dotations et autres. Cette excellente soirée se finissait avec le succulent repas élaborer par Michel et Françoise Vuillier. Encore un grand merci à tous les participants ainsi que les bénévoles...

  3. Middle Pleistocene Climate Change in the Colorado Rocky Mountains Indicated by Fossil Mammals from Porcupine Cave (United States)

    Wood, David L.; Barnosky, Anthony D.


    Fossiliferous sediments from The Pit Locality in Porcupine Cave, Park County, Colorado, span multiple glacial and interglacial cycles between ca. 800,000 and 400,000 yr B.P. at 2900 m elevation. The uppermost cycle probably represents oxygenisotope glacial Stage 12 (stratigraphic Levels 4 and 3) and interglacial Stage 11 (Levels 3, 2, and 1) as determined by arvicoline biostratigraphic data that place the sequence between 487,000 and 365,000 yr B.P. A no-analog assemblage comprising the bog lemming Mictomys meltoni (of the M. borealis lineage) and the sagebrush vole Lemmiscus curtatus (= Lagurus curtatus) characterizes both the glacial and the interglacial deposits. Climatographs for these two species suggest that, compared to present conditions, the following local climatic limits can be imposed on oxygenisotope Stages 12 and 11: (1) January effective moisture was greater, resulting from average temperatures of at least 5°C cooler and/or at least 15 mm more precipitation; (2) January solar radiation was lower by at least 75 Langleys; (3) effective July solar radiation might have been lower by at least 50 Langleys. Seasonal temperature extremes were not necessarily different from those of the present, but seasonal precipitation was more equable. Relative abundance of mammal taxa and sedimentological data indicate that aridity increased at the onset of the interglacial.

  4. Designing acorn protection for direct seeding of quercus species in high predation areas

    Directory of Open Access Journals (Sweden)

    Jose A. Reque


    Full Text Available Aim of the study: a To present the trial-and-error approach followed in the design and patent of a manufactured seed and seedling protector effective against mice and voles, rabbits, wild boar and deer ( b To assess the viability of direct oak seeding with and without protection in the complex acorn predation reality of post fire restoration and underplanting in existing pine afforestations. Study area: Northern Plateau of Spain, in an area of extreme acorn predation. Material and methods: We followed a classical trial-and-error approach for problem solving. Different modifications to a wire mesh screen cylinder were tested in subsequent trials aiming to evaluate the effects on acorn predation and early emerging plant survival and growth. The final protector is based on a thin wire mesh cylinder with three innovations: a truncated cone, a circular crown and a sphere compartment. Further we assessed the viability of direct oak seeding with and without protection in the complex acorn predation reality of post fire restoration and underplanting in existing pine afforestations. Main results: The manufactured seed protector was found to be effective against synergic attacks of mice, rodents, wild boars and herbivores. Survival of protected oak was 77% under canopies and 32% in open light conditions two years after sowing. Research highlights: Our results confirm the viability of direct oak seeding for woodland restoration if seed predation is controlled.

  5. Wild small mammals as sentinels for the environmental transmission of antimicrobial resistance. (United States)

    Furness, Lauren E; Campbell, Amy; Zhang, Lihong; Gaze, William H; McDonald, Robbie A


    Antimicrobial resistance (AMR) represents a serious threat to human health worldwide. We have tested the use of free-living small mammals (mice, voles and shrews) as sentinels of variation in the distribution of AMR in the environment and the potential for transmission from the natural environment to animal hosts. Escherichia coli isolated from the faeces of small mammals trapped at paired coastal and inland sites were tested for resistance to four antibiotics: trimethoprim, ampicillin, ciprofloxacin and cefotaxime. Coastal individuals were over twice as likely to carry AMR E. coli than inland individuals (79% and 35% respectively), and both between-site and between-species variation was observed. Animals from coastal populations also excreted increased numbers of AMR E. coli and a greater diversity of E. coli phylotypes, including human-associated pathogenic strains. Small mammals appear to be useful bioindicators of fine-scale spatial variation in the distribution of AMR and, potentially, of the risks of AMR transmission to mammalian hosts, including humans. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  6. Results of long-term genetic monitoring of animal populations chronically irradiated in the radiocontaminated areas

    Energy Technology Data Exchange (ETDEWEB)

    Goncharova, R.; Riabokon, N. [Institute of Genetics and Cytology, National Academy of Sciences of Belarus, Minsk (Belarus)


    The artificial geochemical land where all organisms lived and will live under the conditions of increased level of radiation was set up due to the Chernobyl disaster in 1986. An urgent necessity for studying the various biological effects of chronic influence of low intensity radiation on both individual organisms and populations arose. Combined cytogenetic and radioecological investigations in wild populations of terrestrial small mammals (bank vole = Clethrionomys glareolus, Schreber and yellow-necked mouse = Apodemus flavicollus, Melchior) and in laboratory mice have been carried out by our laboratory since 1986. Our test organis