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Bifidobacterium castoris strains isolated from wild mice show evidence of frequent host switching and diverse carbohydrate metabolism potential /
No full textMembers of the gut microbiota genus Bifidobacterium are widely distributed human and animal symbionts believed to exert beneficial effects on their hosts. However, in-depth genomic analyses of animal-associated species and strains are somewhat lacking, particularly in wild animal populations. Here, to examine patterns of host specificity and carbohydrate metabolism capacity, we sequenced whole genomes of Bifidobacterium isolated from wild-caught small mammals from two European countries (UK and Lithuania). Members of Bifidobacterium castoris, Bifidobacterium animalis and Bifodobacterium pseudolongum were detected in wild mice (Apodemus sylvaticus, Apodemus agrarius and Apodemus flavicollis), but not voles or shrews. B. castoris constituted the most commonly recovered Bifidobacterium (78% of all isolates), with the majority of strains only detected in a single population, although populations frequently harboured multiple co-circulating strains. Phylogenetic analysis revealed that the mouse-associated B. castoris clades were not specific to a particular location or host species, and their distribution across the host phylogeny was consistent with regular host shifts rather than host-microbe codiversification. Functional analysis, including in vitro growth assays, suggested that mouse-derived B. castoris strains encoded an extensive arsenal of carbohydrate-active enzymes, including putative novel glycosyl hydrolases such as chitosanases, along with genes encoding putative exopolysaccharides, some of which may have been acquired via horizontal gene transfer. Overall, these results provide a rare genome-level analysis of host specificity and genomic capacity among important gut symbionts of wild animals, and reveal that Bifidobacterium has a labile relationship with its host over evolutionary time scales
New data on the diversity and distribution of the Balkan Tachinidae (Diptera: Oestroidea) /
No full textData on 48 species of the family Tachinidae from the Balkan Peninsula are listed. Of them, 27 species are recorded for the first time for different Balkan countries, specifically for Bulgaria (12 spp.), Croatia (8 spp.), Greece (6 spp.) and Slovenia (1 sp.). These records also include four species considered as new records for the fauna of the Balkan Peninsula: Athrycia curvinervis, Admontia grandicornis, Aphantorhaphopsis siphonoides (first Bulgarian records) and Prosethilla kramerella (first Croatian record). The remaining 21 species listed are recorded from only one or two countries in this region and are considered as regionally rare. However, a considerable number of new findings is not considered as regionally rare records and might be explained by the insufficient knowledge of the family in some countries of this region
Angling counts: Harnessing the power of technological advances for recreational fishing surveys /
No full textAs the popularity of recreational fishing gathers global momentum, so does the importance of knowing the number of active anglers and their spatial behaviour. Conventional counting methods, however, can be inaccurate and time-consuming. Here we present two novel methods to monitor recreational fishing applied in Kaunas water reservoir (ca 65 km2), Lithuania, comparing their performance to a conventional visual count. First, we employed a remotely piloted fixed wing drone which conducted 39 missions distributed over one year and compared its accuracy to conventional visual land or boat-based counts. With these data we developed a linear model to predict the annual number of anglers depending on weekday and ice conditions. Second, we used anonymous data from a popular GPS-enabled sonar device Deeper®, used by anglers to explore underwater landscapes and to find fish. The sonar usage probability was calibrated with angler observations from drones using Bayesian methods, demonstrating that at any given time ~2 % of anglers are using the sonar device during the open water season and ~15 % during the ice fishing season. The calibrated values were then used to estimate the total number of anglers, given the daily records of sonar usage in Kaunas water reservoir. The predicted annual number of anglers from both linear drone-based and Bayesian sonar-based methods gave similar results of 25 and 27 thousand anglers within the area during the period of day surveyed, which corresponded to nearly 110 thousand angling trips in the total reservoir area annually. Our study shows high potential of both drone and fish finder digital devices for assessing recreational fishing activities through space and time
Analysis of interannual and seasonal nearshore bar behaviour observed from decadal optical satellite data in the Curonian Spit, Baltic Sea /
No full textLong-term observations of nearshore bar behaviour are a vital component of coastal monitoring, management, and prediction. Optical satellite remote sensing enables the possibility of such observations over large spatial areas, but its full potential remains unexploited. This study assessed alongshore variability in cross-shore nearshore bar behaviour on a wave-dominated multi-bar coast of the Curonian Spit (south-eastern Baltic Sea) between 2011 and 2021, using satellite-derived bar data. Nearshore bars were extracted from a time series of PlanetScope and RapidEye satellite images with an automated GIS-based algorithm, previously proposed by the study authors. The cross-shore behaviour of a multiple bar system was analysed by adapting traditional bathymetry-based analysis techniques to satellite-derived data that included bar crestlines and images of multi-scale Relative Bathymetric Position Index (RBPI). The analysis was performed on 1071 shore-perpendicular transects. Multi-bar onshore and offshore migration rates were quantified on interannual and seasonal timescales. The results show that, on an interannual timescale, bars migrated offshore at rates up to 9.7 m/month, while the rates of onshore migration reached up to 11 m/month. During the months of low wave energy, bars moved offshore at rates up to 6.2 m/month, and during the months of high wave energy, up to 12.9 m/month. However onshore migration rates, during the months of low and high wave energy, reached up to 7.0 and 13.4 m/month, respectively. A complex empirical orthogonal function (CEOF) analysis was performed on RBPI-derived cross-shore profiles, and cyclic offshore directed bar behaviour was examined. For the first time, the net offshore migration (NOM) cycle with bar cycle return periods of 1.8 to 13.5 years was investigated on the south-eastern Baltic Sea coast. Bar cycle return periods increased and rates of bar cross-shore migration decreased from north to south along the Curonian Spit. Similar nearshore bar behaviour regions were identified using clustering analysis based on quantified temporal and morphological characteristics of the bars. Factors controlling alongshore variability in bar cross-shore behaviour were determined. The study results suggest that small alongshore variations in nearshore hydrodynamics, caused by the local wave climate and its interplay with the shoreline orientation, determine the morphological and temporal variability of the multi-bar system in the Curonian Spit
Molecular identification of Sarcocystis species in sheep from Lithuania /
No full textData on the distribution of different Sarcocystis species in various muscles of sheep are scarce. In the present study, 190 diaphragm, oesophagus, and heart muscle samples of 69 sheep raised in Lithuania were examined for the presence of Sarcocystis spp. Under a light microscope, two morphological types of microcysts corresponding to S. arieticanis and S. tenella were detected. Eight and 12 sarcocysts of S. arieticanis and S. tenella, respectively, were isolated and characterised by the sequencing of a portion of cox1. The sequence comparisons revealed the highest similarity between European and Asian isolates of S. arieticanis and S. tenella obtained from domestic sheep and other wild Caprinae hosts. Based on peptic digestion, nested PCR targeting cox1, and sequencing, a 100% infection prevalence of S. arieticanis and S. tenella was observed in the 69 studied animals. The occurrence of S. tenella was significantly higher in the diaphragm than in the oesophagus (χ2 = 13.14, p 0.05). Further molecularly based epidemiological studies are needed to compare the prevalence of Sarcocystis species in various muscles of sheep raised in different geographic regions
Vilkyškiai end-morainic ridge (Rambynas Hill): Evolution of Nemunas river during the Late Glacial and Holocene /
No full textKeys to the avian Haemoproteus parasites (Haemosporida, Haemoproteidae) /
No full textBackground Haemoproteus is a sister genus to malaria parasites (Plasmodium), which both belong to the order Haemosporida (Apicomplexa). Parasites of both genera are flourishing in birds, however, Haemoproteus species are noticeably less investigated. This is unfortunate because knowledge about close relatives of malaria pathogens is important for better understanding the evolutionary origin and basic biological features of the entire group of haemosporidian infections. Moreover, recent findings show that Haemoproteus species can cause severe damage of various bird organs due to megalomeronts and other exo-erythrocytic stages. These haemosporidians are remarkably diverse, but remain neglected partly due to difficulties in species identification. Hundreds of Haemoproteus genetic lineages have been reported in birds, and numerous new lineages are found each year, but most remain unidentified to the species level. Numerous new Haemoproteus pathogens were described during the past 20 years. However, keys for their identification are absent. Identification of Haemoproteus species remains a difficult task and is an obstacle for better understanding of the distribution and epidemiology of these parasites. This study aimed to develop comprehensive keys for the identification of described avian Haemoproteus species using morphological features of their blood stages (gametocytes). Methods Type and voucher preparations of avian Haemoproteus species were accessed in museums in Europe, Australia and the USA. Gametocytes of most described species were examined, and these data formed a background for this study. The data also were considered from published articles containing parasite species descriptions. The method of dichotomous keys was applied. The most difficult steps in the keys were accompanied with references to the corresponding parasite pictures. Results In all, 201 published articles were included in this review. Morphological diagnostic features of gametocytes of all described Haemoproteus species were analysed and compared. Illustrated keys for identification of these parasite species were developed. Available information about the molecular characterization of Haemoproteus parasites was provided. Conclusion This review shows that 177 described species of avian Haemoproteus can be distinguished and identified in blood films using morphological characters of their gametocytes and host cells. These species were incorporated in the keys. Information about possible morphologically cryptic parasites was provided. Molecular markers are available for only 42% of the described Haemoproteus parasites, calling for researchers to fill this gap
Cyanobacteria and their metabolites in mono- and polidominant shallow eutrophic temperate lakes /
No full textMonodominant (one species dominates) or polidominant (multiple species dominate) cyanobacterial blooms are pronounced in productive freshwater ecosystems and pose a potential threat to the biota due to the synthesis of toxins. Seasonal changes in cyanobacteria species and cyanometabolites composition were studied in two shallow temperate eutrophic lakes. Data on cyanobacteria biomass and diversity of dominant species in the lakes were combined with chemical and molecular analyses of fifteen potentially toxin-producing cyanobacteria species (248 isolates from the lakes). Anatoxin-a, saxitoxin, microcystins and other non-ribosomal peptides formed the diverse profiles in monodominant (Planktothrix agardhii) and polidominant (Aphanizomenon gracile, Limnothrix spp. and Planktolyngbya limnetica) lakes. However, the harmfulness of the blooms depended on the ability of the dominant species to synthesize cyanometabolites. It was confirmed that P. agardhii produced a greater amount and diverse range of MCs and other NRPs. In the polidominant lake, isolates of the co-dominant A. gracile, L. planctonica and P. limnetica synthesized no or only small amounts of cyanometabolites. In general, the profile of cyanometabolites was greater in cyanobacteria isolates than in environmental samples, indicating a high potential for toxic cyanobacteria bloom
A review of the subtribe Centaureinae (Asteraceae, Cardueae) in Lithuania with information on new alien species /
No full textThe study’s objective was to overview all Centaureinae species recorded in Lithuania, evaluate the distribution and population state of the newly discovered four alien species and provide information on the residence status, distribution and habitats occupied by all species of the subtribe. The subtribe Centaureinae in Lithuania is now represented by five genera: Centaurea, Leuzea, Psephellus, Serratula and Zoegea. The largest genus in the flora of the country is Centaurea, which includes four native and six alien species. The genus Serratula is represented by one native species, while the genera Leuzea, Psephellus and Zoegea each have one alien species. Tree alien species (an archaeophyte, Centaurea cyanus, and neophytes Centaurea montana and Psephellus dealbatus) are naturalised aliens, whereas Centaurea cheiranthifolia, Centaurea diffusa, Centaurea iberica, Centaurea macrocephala, Leuzea repens and Zoegea crinita are casual aliens. Five species of the subtribe Centaureinae (Centaurea jacea, Centaurea phrygia, Centaurea scabiosa, Centaurea stoebe and Serratula tinctoria) are native to Lithuania. Maps of the distribution of newly discovered alien species in Lithuania are presented
Genetic diversity of inlet systems along non-tidal coasts: examples from the Black Sea and Sea of Azov (Ukraine) /
No full textIn the coastal zone of the oceans, coastal barriers are quite widespread. Within their limits, inlets periodically arise and exist for a certain time, which is of great geological, hydrological, ecological, and navigational significance. Along the coasts where tidal fluctuations predominate, tidal inlets stand out, which are quite well studied in terms of genesis, morpho-, hydro-and litho-dynamics. Inland, semi-isolated marine basins, where tidal fluctuations do not reach a significant amplitude, are called non-tidal seas. Within the coastal barriers of non-tidal seas, channels periodically arise and develop, which are called breaches or pror-vas. Breaches are quite often mentioned in the specialized literature along the coasts of non-tidal seas, but they have not been purposefully studied. In this article, we tried to analyze the conditions for the formation of pror-vas within non-tidal seas based on many years of research. We have identified four hydrodynamic situations in which breaches are formed. The presented variety of situations allows us to identify and describe four genetic types of prorvas: storm-generated, storm-surge-generated, wind-stress-generated, and river-stress (fluvially induced). The presented article is the first attempt to analyze the genetic characteristics of the breaches