Yellow-necked Field Mouse Apodemus Flavicollis Research Articles

Discrimination of the sibling species Apodemus flavicollis and A. sylvaticus (Rodentia, Muridae)

Karyotyping and several molecular methods have allowed successful identification of two morphologically similar wide-ranging Western Palearctic species, the yellow-necked field mouse Apodemus flavicollis (Melchior, 1934) and the long-tailed wood mouse A. sylvaticus (Linnaeus, 1758), but reliable species diagnosis on the basis of morphometric characters is particularly problematic. Although they are easily morphologically distinguishable in Central and Northern Europe, this is not the case in southern parts of their distribution areas. Despite that, we have successfully discriminated A. flavicollis and A. sylvaticus from Serbia (Southern Europe) using geometric and traditional morphometric methods on a data set for ventral crania of specimens previously genotyped by the Inter Simple Sequence Repeat-PCR (ISSR-PCR). Discrimination power of applied approaches was more or less similar. The majority of our results were consistent with those obtained for specimens collected across the Czech Republic (Central Europe). Morphological differences observed herein, as well as those already reported between A. flavicollis and A. sylvaticus from the central and northern parts of their distribution areas, could be the outcome of their biology, i.e. ecological discrepancies, different assumed evolutionary scenarios considering biogeography, phylogeny, history and ontogeny.

Preliminary Study on Microsatellite and Mitochondrial DNA Variation of the Stone MartenMartes foinain Bulgaria

In Europe, distribution of many animal species has been severely restricted to small refugia during the last glacial period. The Balkan Peninsula including Bulgaria has been identified as one of the three main glacial refugia (Randi 2007). To know biogeographical history in Europe, molecualr phylogeographical studies about various European mammal species have been performed: for example, the least weasel Mustela nivalis by the mitochondrial DNA (mtDNA) control region and cytochrome b (Lebarbenchon et al. 2010), the ground squirrel Spermophilus citellus by cytochrome b (Krystufek et al. 2009), the yellow-necked fieldmouse Apodemus flavicollis and the woodmouse A. sylvaticus by cytochrome b (Michaux et al. 2005), the brown bear Ursus arctos by mtDNA control region (Taberlet and Bouvet 1994; Taberlet et al. 1998) and the hedgehogs Erinaceus europaeus and E. concolor by cytochorome b (Santucci et al. 1998). These studies commonly show that distribution of European species was influenced by climate changes in the Quaternary glaciations, and they survived in different ways (Michaux et al. 2005). Studies on the genetic diversity of mammals in Bulgaria as part of the Balkan Peninsula provides further insights to understanding of biogeographical history from the last glacial maximum (LGM) to present in south Europe. The stone marten Martes foina is a medium-sized carnivore of the family Mustelidae, and is distributed from Spain and Portugal in the west, through central and southern Europe, the Middle East, and central Asia, extending as far east as the Altai and Tien Shan Mountains and northwest China (Abramov et al. 2006). This species prefers more open areas than other martens (Sacchi and Meriggi 1995). Its habitat preferences vary in different parts of its range. Martes foina is typically found in deciduous forests, forest edges and open rocky hillsides. In some areas, however, M. foina also inhabits suburban and urban areas, with rare woods (Tikhonov et al. 2008). Because the Balkan Peninsula is one of the southern limit of distribution of M. foina, the analysis of its Balkan population would contribute to further understanding of refugia and phylogeography in Europe. Whereas there have been some phylogenetic studies about the family Mustelidae including M. foina (Marmi et al. 2003; Li et al. 2011) and a microsatellite variation study of M. foina in southern Portugal (Basto et al. 2010), no population genetic studies about this species in Bulgaria have been reported. In the present study, to know the population structure and phylogeography of the Bulgarian population of M. foina, we studied its microsatellite polymorphisms and mtDNA control region variation, and then discuss the genetic diversity in the population.

Yeast-expressed hantavirus Dobrava nucleocapsid protein induces a strong, long-lasting, and highly cross-reactive immune response in mice.

In Europe, Dobrava virus (DOBV) carried by the yellow-necked field mouse Apodemus flavicollis is one of the hantaviruses that can cause severe hemorrhagic fever with renal syndrome in humans. For several hantaviruses, the nucleocapsid (N) protein has proven to be very immunogenic in humans and rodents and even can protect rodents against a virus challenge. To investigate the immunogenicity of DOBV N protein, BALB/c and C57BL/6 mice were immunized three times with a DOBV recombinant N (rN) protein expressed in yeast Saccharomyces cerevisiae together with complete Freund's, with incomplete Freund's, and without adjuvant, respectively. Mice of both strains elicited N-specific antibodies with end-point titers being as high as 1:1,000,000 in C57BL/6 mice. The antibodies induced by DOBV rN protein were highly cross-reactive to the rN proteins of hantaviruses Puumala and Hantaan. In both mice strains, DOBV rN protein induced N-specific antibodies of all IgG subclasses (IgG1, IgG2a, IgG2b, and IgG3), suggesting a mixed Th1/Th2 immune response. Taken together, yeast-expressed DOBV rN protein represents a promising vaccine candidate.

The response of small mammal populations to flooding

Populations of common voles Microtus arvalis (Pallas, 1779), bank voles Clethrionomys glareolus (Schreber, 1780) and yellow-necked field mice Apodemus flavicollis (Melchior, 1834) were studied by live-trapping for two years before and one year after major floods in a flood plain area in central Germany. After floods, the common voles living in undyked grassland died out whereas the population in grassland behind the dyke (control) persisted. Bank voles and yellow-necked field mice in an undyked flood plain forest remained as well. Floods did not decrease survival rates compared to the years prior to floods for bank voles. Survival rates for yellow-necked field mice were highly variable before and after the floods. After floods, reproduction of bank voles commenced later than in previous years while yellow-necked field mice and the common voles on the control plot bred in spring as usual. Young animals were present in the control population of common voles and in the populations of bank voles and yellow-necked field mice in the summer after the floods but not on the flooded grassland. It is concluded that floods have the potential to greatly effect common voles and can lead to low density for at least one growing season. In contrast, bank voles and yellow- necked field mice can continue to thrive after major flood events. By flooding of relevant habitats for short periods of time, combined with other methods of integrated rodent pest management such as grazing, further pressure on common voles could be added to maintain low densities.

The development of mice and voles in an oak forest with a surplus of acorns

Abstract 130 kg of acorns of Common Oak (Quercus robur L.) were distributed on an area of 1.44 ha in an oak forest near Zagreb (Croatia), where acorns were lacking. The influence of this surplus of food on the development of mice and voles was observed from September 1999 till February 2000 on the experimental plot and on an untreated control area before and after offering the acorns. The Redbacked Vole Clethrionomys glareolus was the most abundant and dominant species in both observed areas. After distribution of the acorns, all species of mice, e. g. the Yellownecked Fieldmouse Apodemus flavicollis, the Longtailed Fieldmouse A. sylvaticus, and the Striped Field Mouse A. agrarius, increased up to 4 times in number on the area treated with a surplus of acorns. On the same area, however, all species of voles, e. g. the Redbacked Vole C. glareolus, the Field Vole Microtus agrestis, and the Common Vole M. arvalis, decreased. The numbers of captured and recaptured rodents before and after offering acorns on the treated and the untreated control area were compared by statistical analysis (Chi2‐test). The results show how food can influence the competitive relations between mice and voles.