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1.
Autumn-winter mortality in shrews (Sorex araneus, S. caecutiens, S. minutus) was estimated on the basis of long-term (12 years) live-trapping on the permanent transect lines in Tver oblast. Relative as well as absolute population numbers were estimated. Lesser shrew (S. minutus) has permanently low population numbers. Fall in this species made 40.1%, and it was scattered through this term. Common shrew (Sorex araneus) lose 89.3% of population and in masked shrew (S. caecutiens) those lost was 73.6%. The most lost was found in autumn and winter fall was as least as 38,2% and 30.4% in the latter two species. The mortality is positively dependent on population density in preceding summer and with severity of winter.  相似文献   

2.
The species composition and seasonal dynamics of ectoparasites of the pygmy shrew Sorex minutus L., 1756 were studied in coniferous and mixed forests of the Ilmen-Volkhov Lowland (Novgorod Province of Russia) in 1999–2003. Examination of 265 specimens of the pygmy shrew revealed 670 specimens of ectoparasites that belonged to 13 species: 8 species of fleas, 2 species of ixodid ticks, 1 species of gamasid mites, and 2 species of myobiid mites. In total, 55.8% of shrew specimens were infested with ectoparasites. No more than 4 species of ectoparasites were found simultaneously on one host, and most of the examined shrews (64.8%) were infested with only 1 ectoparasite species. The pygmy shrew had lower infestation intensity and species diversity of acarines and fleas as compared with those of the common shrew Sorex araneus L., 1758 and the bank vole Myodes glareolus (Schreber, 1780) (13 vs. 23 and 29 species, respectively). Unlike these two other hosts, the prevalent ectoparasite of the pygmy shrew was the tick Ixodes trianguliceps Birula, 1895.  相似文献   

3.
The spatial patterns of individually marked juveniles of red-toothed shrews—the masked shrew (Sorex caecutiens), common shrew (S. araneus), and pygmy shrew (S. minutus)—have been determined by comparing the ratio of traps visited by different numbers of animals (0, 1, 2, 3, etc.) with the Poisson distribution and by using the index of relative variance σ2/m. These tests characterize both the distribution of animal load over different points of the study area and the spatial pattern of individual home ranges. A random type of spatial pattern within relatively uniform biotopes prevails in juveniles of all three red-toothed shrew species, regardless of their properties, abundance, and factors accounting for it. This facilitates the formation of a system of non-overlapping home ranges of adult females after wintering. The stability of spatial patterns contributes to the efficiency of population self-regulation.  相似文献   

4.
A chigger mite species, Neotrombicula absoluta Schluger, 1966, previously known only from its type locality in Transcarpathian Region of Ukraine, was found in the vicinity of Kurgolovo Village (Kingisepp District, Leningrad Province, Russia). A single specimen of this species was collected off the common shrew Sorex araneus L. This is the first record of the genus Neotrombicula (which includes the most usual causative agents of trombiculiasis of humans and domestic animals in Europe) in the northwestern part of European Russia.  相似文献   

5.
A FISH with a probe for telomeric and rDNA repeats and immunofluorescence with ANA CREST and antibodies to nucleolae protein B23 were used to study the three-dimensional (3D) organization of fibroblast interphase nuclei in two shrew twin species, Sorex granarius and Sorex araneus, of the Cordon race. Karyotypes of these species are composed of nearly identical chromosomal arms and differ in the number of their metacentrics and the structures of their terminal chromosome regions. In the short arms of S. granarius, 32 of the acrocentrics have large telomeres that contain an average of 218 kb telomere repeats, which alternate with ribosomal repeats. These regions also contain active nucleolar organizing regions (NORs). In contrast, in active NORs in S. araneus are localized at the terminal regions of 8 chromosomal arms (Zhdanova et al., 2005; 2007b). Here, we show that associations of chromosomes by telomeres and the contact of a part of the telomere clusters with the inner nuclear membrane and nucleolus characterize the interphase nuclei of both Sorex granarius and Sorex araneus. We also reveal the partial colocalization of telomere and ribosomal clusters and the spatial proximity of centomeric and telomeric regions in the interphase nuclei of S. granarius. It appears that only ribosomal clusters containing a sufficient number of active ribosomal genes exhibit a connection with the nucleolus. Nucleolus disassembly during the fibroblastís transition to mitosis and the role of the B23 protein in this process have been studied.  相似文献   

6.
This review summarizes available data on the problem of taxonomic and evolutionary differentiation in the “araneus” groups of species of the genus Sorex (Eulipotyphla, Mammalia). Report 2 describes the hierarchical structuring, population system, and interracial hybrid zones in the common shrew (Sorex araneus).  相似文献   

7.
This review summarizes the available data on multilevel differentiation in the araneus species group of the genus Sorex (Eulipotyphla, Mammalia). Communication 1 gives basic information about the biology and morphological and karyotypic differentiation of some species belonging to this genus, as well as about the subdivision of one of the species, the common shrew (Sorex araneus), into intraspecific chromosomal races. The list of the 75 races known so far is included (26 of them dwell in Russia).  相似文献   

8.
The composition of two samples of the masked shrew Sorex caecutiens Lax. from the middle taiga zone of the European part of Russia is analyzed with consideration of morphometric data. Analysis of individual variability of shrews revealed special distinctions of subspecies organization within the climatic zone.  相似文献   

9.
The value of fluctuating asymmetry (FA) of trees and small mammals is considered as an indicator of developmental instability. The urban territories with recreation zones, sites with increased radiation background, and the areas affected by mining facilities have been analyzed as anthropogenically transformed areas. The following tree and small mammalian species are the objects of the study: Siberian silver birch (Betula platyphylla), spreading birch (B. divaricata), dwarf birch (B. exilis), shrub alder (Duschekia fruticosa), basket willow (Salix viminalis), northern red-backed vole (Clethrionomys rutilus), tundra vole (Microtus oeconomus), Laxmann’s shrew (Sorex caecutiens), and tundra shrew (S. tundrensis). In total, 60000 leaves have been measured and 3500 rodent sculls have been examined. The issues of selection of bioindicator species and the factors distorting the results of environmental quality assessment according to developmental instability are discussed. A statistically significant increase in FA of plants is recorded in urban territories as compared with the wildlife biotopes. A positive correlation of FA value with transport load, concentration of heavy metals in soil, and atmospheric air pollution is observed. The proximity to a roadway and the state of road pavement influence the FA value. The main source of pollution in the administrative center (Yakutsk) is motor vehicles; correspondingly, large streets and crossroads with a high transport load are the most polluted sites. As for the industrial center (city of Mirnyi), pollution spreads from the areas affected by mining to the residential area. The main pollution source in a small administrative center (city of Aldan) is the federal highway. It is recommended to concurrently use the FA characteristics of plant and animals in the area affected by the mining industry. Characteristic of this industry is withdrawal of large areas of natural landscapes; typically, transformed plots alternate weakly affected plots. The specific features of the effects of diamond, gold, and coalmining industries, as well as oil and gas field development, are discussed, which should be taken into account in sampling for bioindication. The problem of bioindication in the areas completely devoid of soil and plant cover can be solved by biotesting via assessment of bunching onion seed germination rate and the rate of mitotic aberrations. An increase in the FA level in trees and small mammals is observed in the areas transformed by the mining industry displaying a chronically increased radiation background and oil-polluted as a result of technogenic accidents. The use of FA index makes it possible to estimate the environmental quality and to compare the state of territories located under different natural and climatic conditions and influenced by multicomponent anthropogenic impacts differing in their strength and genesis, which interferes with their comparison.  相似文献   

10.
This study assessed the taxonomic hierarchy of the phylum Firmicutes as well as elucidated the isolation and classification states of novel Firmicutes species isolated from Korean territory. The hierarchical classification system of the phylum Firmicutes has been developed since 1872 when the genus Bacillus was first reported and has been generally adopted since 2001. However, this taxonomic hierarchy is still being modified. Until Feb. 2017, the phylum Firmicutes consisted of seven classes (Bacilli, Clostridia, Erysipelotrichia, Limnochordia, Negativicutes, Thermolithobacteria, and Tissierellia), 13 orders, 45 families, and 421 genera. Firmicutes species isolated from various environments in Korea have been reported from 2000, and 187 species have been approved as of Feb. 2017. All Firmicutes species were affiliated with three classes (Bacilli, Clostridia, and Erysipelotrichia), four orders (Bacillales, Lactobacillales, Clostridiales, and Erysipelotrichales), 17 families, and 54 genera. A total of 173 species belong to the class Bacilli, of which 151 species were affiliated with the order Bacillales and the remaining 22 species with the order Lactobacillales. Twelve species belonging to the class Clostridia were affiliated within only one order, Clostridiales. The most abundant family was Bacillaceae (67 species), followed by the family Paenibacillaceae (56 species). Thirteen novel genera were created using isolates from the Korean environment. A number of Firmicutes species were isolated from natural environments in Korean territory. In addition, a considerable number of species were isolated from artificial resources such as fermented foods. Most Firmicutes species, belonging to the families Bacillaceae, Planococcaceae, and Staphylococcaceae, isolated from Korean fermented foods and solar salterns were halophilic or halotolerant. Firmicutes species were isolated from the whole territory of Korea, especially large numbers from Provinces Gyeonggi, Chungnam, and Daejeon.  相似文献   

11.
Previously, we described the unique feature of telomeric regions in Iberian shrew Sorex granarius: its telomeres have two ranges of size, very small (3.8 kb of telomeric repeats on average) and very large discontinuous telomeres (213 kb) interrupted with 18S rDNA. In this study, we have demonstrated extraordinary replication pattern of S. granarius large telomeres that have not been shown before in other studied mammal. Using the ReD-FISH procedure, we observed prolonged, through S period, large telomere replication. Furthermore, revealed ReD-FISH asymmetric signals were probably caused by partial replication of telomeres within an hour of 5-bromodeoxyuridine treatment due to the large size and special organization. We also found that in contrast to the telomeric halo from primary fibroblasts of bovine, mink, and common shrew, telomere halo of S. granarius consists of multiple loops bundled together, some of which contain rDNA. Here, we suggested several replicons firing possibly stochastic in each large telomere. Finally, we performed the TIF assay to reveal DNA damage responses at the telomeres, and along with TIF in nuclei, we found large bodies of telomeric DNA and ?-H2AX in the cytoplasm and on the surface of fibroblasts. We discuss the possibility of additional origin activation together with recombination-dependent replication pathways, mainly homologous recombination including BIR for replication fork stagnation overcoming and further S. granarius large telomere replication.  相似文献   

12.
This study is aimed at analyzing the total mercury in the tissues of mammals adapted to a semiaquatic or subterranean lifestyle and at analyzing the possible role of their antioxidant system in heavy metal detoxication. The water shrew Neomis fodiens Pennant, 1771, European mole Talpa europaea Linnaeus, 1758, muskrat Ondatra zibethicus Linnaeus, 1766, and water vole Arvicola terrestris Linnaeus, 1758 were the species under study. Our results indicate that mercury accumulation in the tissue depends on the age, tissue type, and diet of the species. The highest mercury content was recorded in water shrew tissues compared to other species. Age-dependent accumulation of the toxicant in the animals is reported. A correlation between mercury accumulation and catalase activity in the kidneys of the animals studied was found.  相似文献   

13.
The absence of significant distinctions between the species of the genus Planorbarius in the narrow sense (P. corneus, P. banaticus, P. purpura, and P. grandis) has been established. All investigated species had identical chromosomal formulas (2n = 30m + 6sm = 36) and fundamental numbers (FN = 72). Reproducible distinctions between them were not found by total complement length (TCL), relative length of chromosomes (RL), and centromeric indexes. The species selected on the basis of genetic marking differed clearly by centromeric index of chromosome 12, which confirms the allospecies frame of P.corneus s. lato.  相似文献   

14.
We examined the temporal variation in capture rates of shrewsNotiosorex crawfordi (Coues, 1877) and Sorex ornatus (Merriam, 1895) in 20 sites representing fragmented and continuous habitats in southern California, USA. InN. crawfordi, the temporal variation was significantly correlated with the mean capture rates. Of the 6 landscape variables analyzed (size of the landscape, size of the sample area, altitude, edge, longitude and latitude), sample area was positively correlated with variation in capture rates ofN. crawfordi. InS. ornatus, longitude was negatively correlated with variation in capture rates. Analysis of the effect of precipitation on the short- and long-term capture rates at 2 of the sites showed no correlation between rainfall and capture rates of shrews even though peak number of shrews at both sites were reached during the year of highest amount of rainfall. A key problem confounding capture rates of shrews in southern California is the low overall abundance of both shrew species in all habitats and seasons.  相似文献   

15.
We conducted a cytogenetic study of four hyline frog species (Dendropsophus elegans, D. microps, D. minutus and D. werneri) from southern Brazil. All species had 2n = 30 chromosomes, with interspecific and intraspecific variation in the numbers of metacentric, submetacentric, subtelocentric and telocentric chromosomes. C-banding and fluorochrome staining revealed conservative GC-rich heterochromatin localized in the pericentromeric regions of all species. The location of the nucleolus organizer regions, as confirmed by fluorescent in situ hybridization, differed between species. Telomeric probes detected sites that were restricted to the terminal regions of all chromosomes and no interstitial or centromeric signals were observed. Our study corroborates the generic synapomorphy of 2n = 30 chromosomes for Dendropsophus and adds data that may become useful for future taxonomic revisions and a broader understanding of chromosomal evolution among hylids.  相似文献   

16.
Chaetogastra is the largest genus in Melastomateae, with about 165–190 species. The genus was only recently resurrected, based on species that have been traditionally treated in Tibouchina sects. Diotanthera, Pseudopterolepis, Purpurella and Simplicicaules. This article presents 15 chromosome counts for the genus, a review of the available counts and also a discussion of these counts in a systematic context. Although the sampling in the genus is still poor, the data found in the literature and in our research indicate x=9 as the base chromosome number for the genus. We also found that euploidy may be common in Chaetogastra, with diploid, tetraploid and hexaploid species. Basic chromosome numbers also seem to be a taxonomic character that distinguishes Chaetogastra (x=9) from Brachyotum (x=10).  相似文献   

17.
A complex of the heteropteran genera centering around Peribalus Mulsant et Rey and Holcostethus Fieber is considered. The genus Dryadocoris Kirkaldy reveals no relationship with the above genera and is believed to represent a separate clade of the family Pentatomidae. The genera Peribalus and Holcostethus are revised. The former includes three subgenera: Peribalus s. str. with two species, Asioperibalus subgen. n. (type species Cimex inclusus Dohrn) with six species, and Tianocoris subgen. n. (type species Holcostethus manifestus Kiritshenko) with two species. Holcostethus embraces two subgenera: Holcostethus s. str. and the monotypic Enigmocoris subgen. n. (type species H. fissiceps Horváth). Two new species are described: Peribalus tianshanicus sp. n. from the Tien Shan Mts. and P. przewalskii sp. n. from the northern part of China (Huan He River). P. capitatus Jakovlev and P. vernalis (Wolff) are downgraded to subspecies of P. strictus (F.). P. ovatus Jakovlev is synonymized with P. inclusus (Dohrn). Two new monotypic genera related to the revised complex of genera are established, Paraholcostethus gen. n. (type species Peribalus breviceps Horváth) and Himalayastethus gen. n. (type species H. pilosus sp. n. from Kashmir). A key to, and morphometric characters for all the taxa considered are provided. The key characters, including both male and female genitalia, are illustrated, and distributional maps are given.  相似文献   

18.
Gudrun Strauss 《BioControl》2009,54(2):163-171
Neodryinus typhlocybae (Ashmead) (Hymenoptera: Dryinidae) is a natural enemy of the planthopper Metcalfa pruinosa (Say) (Hemiptera: Flatidae), introduced from North America into Europe and regionally established as a pest species. Prior to possible utilization of the parasitoid as a biocontrol agent in Austria, its potential negative impacts on eight native plant- and leaf-hopper species were examined in the laboratory. Non-target species were selected according to the following criteria (a) occurrence in Austria, (b) close phylogenetic relationship with M. pruinosa, (c) larvae free-living and surface-dwelling, (d) phenology, (e) larval size, (f) ecological similarity with M. pruinosa and (g) availability of sufficient numbers of individuals. The Auchenorrhyncha species Issus coleoptratus (Fabricius), Chloriona smaragdula (Stål), Conomelus anceps (Germar), Alebra wahlbergi (Boheman), Empoasca sp., Idiocerus stigmaticalis (Lewis), Macrosteles septemnotatus (Fallén) and Japananus hyalinus (Osborn) were chosen for testing. Larvae from both the target and the non-target species were offered separately to N. typhlocybae females in no-choice laboratory tests and all attacks, instances of host feeding and parasitizations were recorded. No non-target species was attacked, fed upon or parasitized by N. typhlocybae, whereas M. pruinosa was attacked frequently. This study supports the assumption that the host range of N. typhlocybae is restricted to Flatidae, of which only the introduced species occurs in Austria. Direct negative effects on other Auchenorryncha species in Austria are therefore unlikely to occur.  相似文献   

19.
Invasive candidiasis is caused mainly by Candida albicans, but other Candida species have increasing etiologies. These species show different virulence and susceptibility levels to antifungal drugs. The aims of this study were to evaluate the usefulness of the non-conventional model Caenorhabditis elegans to assess the in vivo virulence of seven different Candida species and to compare the virulence in vivo with the in vitro production of proteinases and phospholipases, hemolytic activity and biofilm development capacity. One culture collection strain of each of seven Candida species (C. albicans, Candida dubliniensis, Candida glabrata, Candida krusei, Candida metapsilosis, Candida orthopsilosis and Candida parapsilosis) was studied. A double mutant C. elegans AU37 strain (glp-4;sek-1) was infected with Candida by ingestion, and the analysis of nematode survival was performed in liquid medium every 24 h until 120 h. Candida establishes a persistent lethal infection in the C. elegans intestinal tract. C. albicans and C. krusei were the most pathogenic species, whereas C. dubliniensis infection showed the lowest mortality. C. albicans was the only species with phospholipase activity, was the greatest producer of aspartyl proteinase and had a higher hemolytic activity. C. albicans and C. krusei caused higher mortality than the rest of the Candida species studied in the C. elegans model of candidiasis.  相似文献   

20.
Yeast abundance and species diversity in the latex of rubber tree Hevea brasiliensis (Willd. ex Juss.) Müll. Arg., on its green leaves, and in soil below the plant were studied. The yeasts present in the fresh latex in numbers of up to 5.5 log(CFU/g) were almost exclusively represented by the species Candida heveicola. This species was previously isolated from Hevea latex in China. In the course of natural modification of the latex (turned from liquid to solid form), yeast diversity increased, while yeast abundance decreased. The yeasts in thickened and solidified latex were represented by typical epiphytic and ubiquitous species: Kodamea ohmeri, Debaryomyces hansenii, Rhodotorula mucilaginosa, and synanthropic species Candida parapsilosis and Cutaneotrichosporon arboriformis. The role of yeasts in latex modification at the initial stages of succession and their probable role in development of antifungal activity in the latex are discussed.  相似文献   

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