Publications by authors named "Viatcheslav V Rozhnov"

A new species of gymnure of the genus Neohylomys is described from northern Vietnam based on morphological and molecular differences. The species Neohylomys vietnamensis sp. nov.

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Background: The paper presents novel findings of little-known species of rodents, the blind tree mice in Son La Province, Vietnam, with the first morphological and genetic characterisation and taxonomical description of the new species, . The study also summarises all the data available on this genus species distribution, museum collections and notes on its taxonomy, which are important to establish the proper conservation status of the species. An exhaustive map of the findings is provided, along with a refined taxonomic key for all six currently morphologically characterised species of the genus.

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The allelic diversity of exon 2 (DQB gene) and exon 3 (DRB gene) of major histocompatibility complex class II was studied for the first time in two species of the landlocked pinnipeds, Baikal (N = 79) and Caspian (N = 32) seals, and these were in compared with the widespread Arctic species, the ringed seal (N = 13). The analysis of the second exon comprising the antigen-binding region revealed high allelic diversity in all three species but the pattern of the diversity was the most specific for the Baikal seal. This species differs from the other two by the smallest number of alleles in the population, yet they have the largest number of alleles per individual and by the maximum similarity of individual genotypes.

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Beluga whales play a critical role in the subsistence economies and cultural heritage of Indigenous communities across the Arctic, yet the effects of Indigenous hunting on beluga whales remain unknown. Here, we integrate paleogenomics, genetic simulations, and stable C and N isotope analysis to investigate 700 y of beluga subsistence hunting in the Mackenzie Delta area of northwestern Canada. Genetic identification of the zooarchaeological remains, which is based on radiocarbon dating, span three time periods (1290 to 1440 CE; 1450 to 1650 CE; 1800 to 1870 CE), indicates shifts across time in the sex ratio of the harvested belugas.

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The paper presented novel findings of little-known species of rodents the Tonkin limestone rat in Cao Bang Province, Vietnam with its morphological and genetic characterisation. The study summarises data on the distribution of this data-deficient species, available museum collections, genetic samples, information on its taxonomy and ecology, important to establish the proper conservation status of the species. An exhaustive map of the findings is provided.

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Climate changes cause a dramatical increase in the ice-free season in the Arctic, forcing polar bears ashore, closer to human settlements associated with new and non-natural food objects. Such a diet may crucially transform the intestinal microbiome and metabolism of polar bears. The aim of this study was to characterize changes in the gut bacterial and fungal communities resulting from the transition to anthropogenic food objects by the means of 16S and ITS metabarcoding.

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Although the home range and habitat selection of animal species is among the fundamental pieces of biological information collected by research projects during recent decades, published information on the snow leopard (Panthera uncia) home range is limited. The Altai Mountains of central Asia contain some of the largest and most important remaining conservation landscapes for snow leopards globally, but there is a limited understanding of the species' ecology in this region. First, we used the data from 5 snow leopards equipped with GPS collars at four study sites in the Altai Mountains of Mongolia to broadly characterize patterns of home range use between 2013 and 2019.

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Article Synopsis
  • Aichi Target 11 aimed to protect at least 17% of terrestrial areas by 2020, but Asia significantly underperformed with only 13.2% protected, raising concerns for the 30% goal by 2030.
  • The study found that 73.1% of terrestrial ecoregions in Asia had less than 17% representation, and only 7% of protected areas were assessed for management effectiveness, indicating major gaps in conservation efforts.
  • To help meet post-2020 biodiversity targets, the authors recommend improving reporting and conservation measures, restoring degraded landscapes, and enhancing transboundary protected areas.
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The mouse-deer or chevrotains are the smallest of the ungulates and ruminants. They are characterized by a number of traits which are considered plesiomorphic for the Artiodactyla order. The objective of this study was to examine sleep in the lesser mouse-deer (Tragulus kanchil), which is the smallest in this group (body mass < 2.

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Several Arctic marine mammal species are predicted to be negatively impacted by rapid sea ice loss associated with ongoing ocean warming. However, consequences for Arctic whales remain uncertain. To investigate how Arctic whales responded to past climatic fluctuations, we analysed 206 mitochondrial genomes from beluga whales (Delphinapterus leucas) sampled across their circumpolar range, and four nuclear genomes, covering both the Atlantic and the Pacific Arctic region.

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The existence of a trans-boundary population of the snow leopard (Panthera uncia) that inhabits the massifs of Tsagaanshuvuut (Mongolia) - Tsagan-Shibetu (Russia) was determined through non-invasive genetic analysis of scat samples and by studying the structure of territory use by a collared female individual. The genetic analysis included species identification of samples through sequencing of a fragment of the cytochrome b gene and individual identification using a panel of 8 microsatellites. The home range of a female snow leopard marked with a satellite Global Positioning System (GPS) collar was represented by the minimum convex polygon method (MCP) 100, the MCP 95 method and the fixed kernel 95 method.

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The Hainan gymnure (Mammalia, Lipotyphla), endemic to Hainan Island (China), is one of the rarest and least-known species within the family Galericidae. The IUCN Red List inferred it as an endangered species due to ongoing population decline caused by natural habitat loss. A recent biodiversity survey has revealed to be rather common in northern Vietnam.

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Gymnures are an ancient group of small insectivorous mammals and are characterized by a controversial taxonomic status and the lack of a description of karyotypes for certain species. In this study, conventional cytogenetic techniques (Giemsa, CBG- and GTG-banding, Ag-NOR), CMA-DAPI staining, and fluorescent hybridization (FISH) with telomeric DNA probes were used to examine for the first time the karyotypes of lesser gymnures of group Müller, 1840 from northern and southern Vietnam. All studied specimens had karyotypes with 2=48, NF=64.

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The phylogeographic pattern of across most of its geographic range was investigated based on existing sequencing from GenBank and new original data from Vietnam to evaluate its natural subdivision and taxonomic structure in Indochina and neighboring regions. Seven major phylogenetic clusters/groups are apparent on the cytochrome (Cyt ) and cytochrome с oxydase subunit 1 gene (COI) trees, corresponding to geographical subpopulations of the species. Among them, distinct position of most divergent, clade Msur7 is also supported by analyses of nuclear (IRBP) gene.

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We analyzed the complete mitochondrial cytochrome b (cytb) gene and fragments of four nuclear loci: ApoB, RAG2, IRBP1 and BRCA1. These data allowed us to provide new insights into the diversity of the Asiatic water shrews of Indochina. A new, highly divergent genetic lineage of Chimarrogale was found in southern Vietnam, and this lineage included specimens from the provinces of Kon Tum, Dak Lak, and Lam Dong.

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Article Synopsis
  • * It investigates the shifts in hearing responses before and after exposure to the noise, showing a notable increase in the threshold of sensitivity—up to 33 dB at supra-threshold levels.
  • * The findings suggest that post-exposure hearing responses depend on stimulus levels, with higher levels leading to lesser suppression of responses, indicating a complex interaction within the cochlea's functioning.
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To date, most research on the adverse effects of anthropogenic noise on marine mammals has focused on auditory and behavioral responses. Other responses have received little attention and are often ignored. In this study, the effect of acoustic noise on heart rate was examined in captive belugas.

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Temporary threshold shift (TTS) and the discrimination of spectrum patterns after fatiguing noise exposure (170 dB re 1 μPa, 10 min duration) was investigated in a beluga whale, Delphinapterus leucas, using the evoked potential technique. Thresholds were measured using rhythmic (1000/s) pip trains of varying levels and recording the rhythmic evoked responses. Discrimination of spectrum patterns was investigated using rippled-spectrum test stimuli of various levels and ripple densities, recording the rhythmic evoked responses to ripple phase reversals.

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To better understand the spatial structure of Amur tigers (Panthera tigris altaica) at the southern edge of their range we fitted 14 tigers (6♀♀ and 8♂♂) with 15 GPS-Argos collars between 2008 and 2011 in 2 study sites: the Ussuriskii Reserve of southern Sikhote-Alin and the Land of the Leopard National Park in southwest Primorye, Russian Far East. Fixed kernel estimates of male home ranges were larger than those of female home ranges (P < 0.05 [mean 95% fixed kernel(♀) = 401 ± 205 km(2) ; mean 95% fixed kernel(♂) = 778 ± 267 km(2)]).

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Based on molecular data for mitochondrial (Cyt b, COI) and nuclear (IRBP, GHR) genes, and morphological examinations of museum specimens, we examined diversity, species boundaries, and relationships within and between the murine genera Chiromyscus and Niviventer. Phylogenetic patterns recovered demonstrate that Niviventer sensu lato is not monophyletic but instead includes Chiromyscuschiropus, the only previously recognized species of Chiropus. To maintain the genera Niviventer and Chiropus as monophyletic lineages, the scope and definition of the genus Chiromyscus is revised to include at least three distinct species: Chiromyscuschiropus (the type species of Chiromyscus), Chiromyscuslangbianis (previously regarded as a species of Niviventer), and a new species, described in this paper under the name Chiromyscusthomasi sp.

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The influence of fatiguing sound level and duration on post-exposure temporary threshold shift (TTS) was investigated in two beluga whales (Delphinapterus leucas). The fatiguing sound was half-octave noise with a center frequency of 22.5 kHz.

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Recent investigations of Southeast Asian white toothed shrews belonging to the genus Crocidura have revealed discrepancies between the results of morphological and molecular studies. The following study concerns three species of Crocidura occurring in Vietnam, namely Crocidura attenuata, Crocidura tanakae and Crocidura wuchihensis, and an undescribed fourth species revealed by molecular analysis. For many years Crocidura attenuata has been known to occur in Vietnam but, until very recently, the morphologically similar and comparably sized Crocidura tanakae was believed to be restricted to Taiwan.

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Temporary threshold shift (TTS) after loud noise exposure was investigated in a male and a female beluga whale (Delphinapterus leucas). The thresholds were evaluated using the evoked-potential technique, which allowed for threshold tracing with a resolution of ~1 min. The fatiguing noise had a 0.

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Tonkinomys daovantieni was recently described from Northern Vietnam, but very sparse information exists for the taxon. We report for the first time the karyotype of this species and investigate its phylogenetic position in the Dacnomys division using both mitochondrial and nuclear genetic data. The diploid chromosome number of the species is 2n=44.

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New findings of the white-toothed shrews (Crocidura spp.) from offshore islands of Vietnam are reported. The species identifications have been confirmed by the analysis of complete mitochondrial cytochrome b gene (1140 bp).

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