To study the genetic differentiation and phylogeny of the breeds and populations of reindeer (Rangifer tarandus L.), a test system based on multiplex PCR analysis of 16 highly polymorphic STR markers (Rt6, BMS1788, Rt30, Rt1, Rt9, FCB193, Rt7, BMS745, С143, Rt24, OheQ, С217, С32, NVHRT16, T40 and C276) was developed. Using this test system, 397 animals from 11 samples were studied. Four of these samples belonged to the wild forms of reindeer, while the rest of the samples represented the Nenets, Even, and Evenk breeds reared in different climatic zones of the Russian Federation. For 16 microsatellite loci, 204 alleles were identified, some of which could be considered breed-specific. It was demonstrated that more than 70% of the unique allele pool was concentrated in wild populations of reindeer. Statistical analysis of microsatellite data showed that the developed test system was an effective tool for identifying domesticated and wild forms of reindeer, testing the breed assignment, and determining the migration flows of a species over the vast territory of its distribution.

Wild waterbirds are circulating important RNA viruses, such as avian coronaviruses, avian astroviruses, avian influenza viruses, and avian paramyxoviruses. Waterbird migration routes cover vast territories both within and between continents. The breeding grounds of many species are in the Arctic, but research into this region is rare. This study reports the first Newcastle disease virus (NDV) detection in Arctic Russia. As a result of a five-year study (from 2019 to 2023) of avian paramyxoviruses and avian influenza viruses in wild waterbirds of the Taimyr Peninsula, whole-genome sequences of NDV and H3N8 were obtained. The resulting influenza virus isolate was phylogenetically related to viruses that circulated between 2021 and 2023 in Eurasia, Siberia, and Asia. All NDV sequences were obtained from the Herring gull, and other gull sequences formed a separate gull-like clade in the sub-genotype I.1.2.1, Class II. This may indirectly indicate that different NDV variants adapt to more host species than is commonly believed. Further surveillance of other gull species may help to test the hypothesis of putative gull-specific NDV lineage and better understand their role in the evolution and global spread of NDV.

The industrial pollution in the Norilsk industrial region and its continuous adverse impact on the local ecosystem un derscore the need to study how chemical substances enter and accumulate in living organisms. This study aimed to investigate the accumulation of heavy metals (Zn, Cu, Cd, and Pb) in the kidneys and livers of voles and shrews in habiting areas adjacent to the Nadezhdinsky Metallurgical Plant and the Copper Plant. Animals were captured at sites located an average of 9.2 km from industrial emission sources. A total of 48 kidney and liver samples were analyzed, comprising 24 samples from voles and 24 from shrews. Heavy metal concentrations were determined by atomic absorption spectrometry with plasma and electrothermal atomization using a Kvant-2mt spectrometer. The results indicated that zinc was distributed more homogeneously in the organs of both voles and shrews than the other metals, with its concentration varying 3.8 to 10.5 times less. In contrast, copper exhibited the greatest variability, particularly inrenal tissue, reflecting considerable individual variation in kidney Cu accumulation. Variability analysis further confirmed that the toxic elements exhibited the highest coefficients of variation. Furthermore, pronounced organ-specificdifferences in metal accumulation were observed. The kidneys of both voles and insectivores contained significantly higher levels of copper, cadmium, and lead (P < 0.01–0.001) than their livers. Diet also influenced accumulation patterns, as insectivorous shrews showed elevated concentrations of Cu, Cd, and Pb in their organs relative to herbivorousvoles. Consequently, these findings provide valuable baseline data for assessing the impact of industrial pollution on small mammals and can inform future environmental monitoring in affected areas.