No 2 (2025)

There are four redfish species of the genus Sebastes in the North Atlantic: beaked redfish S. mentella Travin, 1951; Norway redfish S. viviparus Kroyer, 1845; golden redfish S. norvegicus (Ascanius, 1772); Acadian redfish S. fasciatus Storer, 1856. However, the taxonomic status of so-called “giant” Sebastes – redfish with average length above 60 cm of the Irminger Sea, Iceland and Greenland slopes, remains unresolved. Using histological and genetic analysis we studied 17 giants which were collected in the North Atlantic (Irminger Sea) in 2011-2021. Based on the results of analysis of nuclear (RP2 S7) and mitochondrial (D-loop) DNA sequences, which are species-specific for North Atlantic Sebastes, it was established that at least some giants are hybrids between S. norvegicus and S. mentella. A descendant of S. norvegicus and the hybrid S. norvegicus × S. viviparus was also revealed. The results of histological analysis confirmed previously published data on the sterility of giant females, but at the same time showed that the reproductive ability of male appears to be preserved.

It is shown that the complex of florotannins isolated from the marine brown alga Sargassum pallidum protects the pool of the oxidized form of NAD⁺-NADP⁺ from depletion during acute alcohol impact. Restoration of NAD+/NADH ratio provided preservation of redox potential in liver, necessary level of oxidized forms of metabolites of lactate dehydrogenase and glycerol-3-phosphate dehydrogenase shuttle cycles for maintenance of reactions of aerobic glycolysis and gluconeogenesis, pentose phosphate cycle, promoted prevention of tissue hypoxia and normalization of blood glucose level. This provides a basis for recommending the use of florotannin complexes as a prophylactic agent to attenuate the toxic effects of ethanol.

This paper presents a comparative analysis of mitochondrial genome of the anchovy sprat Clupeonella engrauliformis and the Black and Caspian Sea sprat C. cultriventris from the Caspian Sea. The mitogenome of tulka has a length of about 16.6 thousand bp and is characterized by a gene order conservative for herring fishes. The difference between the mitochondrial genomes of anchovy and Black and Caspian Sea sprats from concerns 449 bp (2.7%), including two insertions in the control region, unknown in other representatives of the genus Clupeonella. The differentiation of tulkas is probably related to transgression and degradation of the Pontic Lake-Sea: it began in the Miocene, continued in the Pliocene, and was completed by the Pleistocene. The modern differences of tulkas may be connected with different adaptations of their ancestors to specific conditions in different water bodies – remnants of the Pontic “Mega-lake”.

Studies on distribution of rabbits’ Eimeria were performed during 2020–2021 in foothills of Armenia based on the station of Russian-Armenian Center of Zoology and Parasitology of A.N. Severtsov’s Institute of Ecology and Evolution RAS and a Scientific Center of Zoology and Hydroecology of National Academy of Science of Armenia. In the farms studied there were found 7 species of eimerioses’ (g. Eimeria Schneider, 1875) causative agents: E. coecicola Cheissin 1947, E. exigua Yakimoff, 1934, E. irresidua Kessel & Jankiewicz, 1931, E. magna Pérard, 1925, E. media Kessel, 1929, E. perforans (Leuckart, 1879) Sluiter et Swellengrebel, 1912, E. stiedae (Lindemann, 1865) Kisskalt et Hartmann, 1907 and a giant form we have also detected before which we denotate as E. sp. The work describes the frequencies of appearance of the Eimeria species detected dependent on season. Life cycles have been studied and roles various species play as causative agents are established.

The volatile metabolome, reflecting disease-related specific and nonspecific metabolic changes, forms the “olfactory image” of the disease. We investigated changes in the urine volatile metabolome as a result of mild physical trauma – subcutaneous injection. We showed that detection animals, dogs and mice, distinguished the urinary volatile metabolites of model mice subjected to physical trauma (saline injection) from both intact controls and mice injected with healthy and tumor-affected liver tissue. Two successive injuries increased the similarity of odors between healthy and tumor-affected mice. We conclude that physical trauma contributes significantly to the “olfactory image” of the disease.

The state of the plankton community in the locks of the Volga-Don shipping canal and adjacent sections of the unregulated Volga and the Tsimlyansk reservoir was investigated. It includes 195 species of algae, about 65 species of ciliates and 100 species of zooplankton. The low similarity of the composition of all components of the plankton community between individual gateways made it possible to conclude about the special conditions created in each of them and the formation of a high species richness of all components of the plankton community due to specific species-plankters developing in individual gateways. All components of the planktonic community (phyto-, proto- and metazooplankton) included alien species of “southern” complexes. In sluice chambers, despite constant turbulence, the mortality rate of zooplankters was low. The greatest mortality among the representatives of metazooplankton was typical for filtrators (Rotifera and Cladocera) and was recorded in the end locks of the Volga and Don stairs of the VDSK with high rates of turbidity and mineralization.

An ecological assessment of the habitats of Dianthus superbus according to scales of D.N. Tsyganov is given. The ecological valences (potential and realized) and bionality of the species are calculated. According to climatic factors, D. superbus is a mesobiont, and according to the illumination–shading factor, it is a eurybiont. For all soil factors, D. superbus is a hemistheno- and stenovalent species and belongs to the stenobiont group, therefore, all soil factors are limiting for D. superbus, which limits its wide distribution. The biomorphological features of D. superbus individuals have been studied. The ontogenetic structure of D. superbus cenopopulations (CP) was processed using the new ExOS package (Excel Ontogenetic Spectrum). All D. superbus CP are normal, incomplete, and young according to the delta-omega classification. The ontogenetic spectra are left-sided due to the intensive self-maintenance of the CP in both seminal and vegetative ways.

The effect of bifido- and lactobacilli complex on some indices of non-specific humoral immunity of sturgeon hybrid Acipenser gueldaenstaedti Brandt × A. baeri Brandt has been studied. The level of antimicrobial properties, C-reactive protein, lysozyme and the content of non-specific immune complexes in serum were studied. The study showed a high level of bacteriostatic activity and lysozyme, low content of nonspecific immune complexes in the experimental groups compared to the control, which indicates the immunostimulating effect of bifidobacteria and lactobacilli complex on nonspecific mechanisms of antibacterial defence of fish.