Taxonomic Interpretation of Allopatric Mammalian Forms on the Example of Two Karyoforms of Microtus (Terricola) subterraneus (Rodentia, Arvicolinae) from Eastern Europe.

New European pine vole records from the Novgorod, Kaluga, Voronezh, and Belgorod oblasts were studied by sequencing of the mtDNA cytb gene (1143 bp) and by karyotyping (routine staining and G-banding techniques). The results enabled us to summarize chromosome variability of this species throughout Eastern Europe. In the sample studied, two geographically replacing chromosomal forms have been identified: northern, 2n = 54 (Novgorod and Kaluga oblasts), and southern, 2n = 52 (Voronezh and, presumably, Belgorod oblasts). Our data make the boundaries of these two karyoforms in Eastern Europe more precise and testify to intraspecific level of their taxonomic differentiation.

[RATS OF THE GENUS RATTUS AS HOSTS FOR NATURAL FOCAL INFECTIOUS AGENTS].

The paper reviews the significance of rats of the genus Rattus as hosts for zoogenous infections in a genus formation area (Southeast Asia) as compared to the invasion part of the genus area. The rats of the genus Rattus and their related disease agents are shown to be a uniqe model for the formation and development of a host-pathogen system. In the modern period of urbanization growth, the rats are among few species of warm-blooded vectors that can maintain the anthropurgic foci of feral nidal infections in the cities and towns and transmit their pathogens to the urban population. There are all prerequisites for the high activity of these foci in the native area of rats. By having settled, the rats have carried infectious agents outside this area along all continents in historical times. During invasions, the rats have become carriers of many other infections.

Dynamics of Puumala hantavirus infection in naturally infected bank voles (Clethrinomys glareolus).

Specific features of hantavirus infection in bank vole (Clethrionomys glareolus) were studied in the endemic area of hemorrhagic fever with renal syndrome (HFRS) in the foothills of the Ural mountains, using long-term observations on living animals by the capture-mark-recapture (CMR) method. The results demonstrated that the infection naturally circulating in the voles is chronic (lasting for up to 15 months) and asymptomatic, with a peak of Puumala virus accumulation and release from the organism during the first month after infection. It was shown that the bank vole population includes young animals with maternal immunity, which remain resistant to the Puumala virus infection for 3-3.5 months. The infection rate in voles depended on the age and sexual maturity of animals. The greatest proportion of seropositive animals was observed among overwintered males. Seroconversion in voles was more frequent during the period of high reproductive activity.