| non-repetitive dna sequence divergence in phylogenetically diploid and tetraploid teleostean species of the family cyprinidae and the order isospondyli. | non-repetitive dna of anciently tetraploid teleostean species was analysed for the presence of duplicated sequences. closely related diploid species were investigated in comparison. from the reassociation kinetics of total nuclear dna, rate constants and fraction sizes of classes of repetitive and non-repetitive sequences were determined. dna fractions enriched in the slowest renaturing sequence class were determined. dna fractions enriched in the slowest renaturing sequence class were prepared ... | 1979 | 533669 |
| studies on lectins. xli. isolation and characterization of a blood group b specific lectin from the role of the powan (coregonus lavaretus maraena). | a b-specific lectin from the roe of the powan (coregonus lavaretus maraena), a fish of the salmonidae family, was isolated by affinity chromatography on o-alpha-d-galactosyl polyacrylamide gel. from 630 g of the lyophilized roe, 346 mg of pure lectin was obtained in a single isolation step. the lectin is electrophoretically homogeneous, its sedimentation coefficient s20,w is 2.9s and molecular weight 25 000. the molecular weight of the subunits estimated by electrophoresis in the presence of dod ... | 1978 | 564208 |
| [the causes of the formation of an intensive focus of triaenophoriasis in the upper tuloma river reservoir]. | observations on the triaenophorus crassus invasion in coregonus lavaretus and esox lucius were carried out in the period of 1984 to 1989 in the upper tuloma river [correction of verkhnetulomsk] water reservoir and pechozero water body (the pecha river) which form a common basin. significant differences were noted in the infection rate of fishes with this parasite in the above water bodies. in pechozero, where there are preserved natural conditions and therefore an ecological equilibrium in the h ... | 1991 | 1839932 |
| adrenocortical and adrenomedullary homologs in eight species of adult and developing teleosts: morphology, histology, and immunohistochemistry. | morphology, histology, and immunohistochemistry of the adrenocortical and adrenomedullary homologs (adrenal glands) of the following developing and adult teleosts were examined: salmoniformes-oncorhynchus mykiss (rainbow trout), salmo trutta fario (brown trout), coregonus lavaretus (white fish); cyprinodontiformes-gambusia affinis (mosquito fish). perciformes-dicentrarchus labrax (sea bass), sparus aurata (sea bream), diplodus sargus (white bream), oblada melanura (saddled bream). the anatomical ... | 1997 | 9405124 |
| biomarker responses in whitefish (coregonus lavaretus l. s.l.) experimentally exposed in a large lake receiving effluents from pulp and paper industry. | physiological and biochemical biomarker responses were studied in juvenile whitefish (coregonus lavaretus l. s.l.) exposed experimentally to effluent from the forest industry. the large study area (609 km2), southern lake saimaa, in southeast finland, receives 330,000 m3 d-1 of biologically and 55,000 m3 d-1 of chemically treated effluents, discharged from two integrated elementary chlorine free (ecf) bleached kraft pulp and paper mills, from one ecf pulp mill, and from one mill producing unblea ... | 1998 | 9419275 |
| identification of fish species by reversed-phase high-performance liquid chromatography with photodiode-array detection. | a method for the separation of sarcoplasmic fish proteins by rp-hplc is described. the procedure revealed significant differences useful for reliable identification of fish species. sixteen of the most common finnish freshwater fish species were differentiated by species-specific hplc chromatograms obtained using photodiode-array detection (pad) at 200-350 nm. the analytical column was a hi-pore rp-304 reversed-phase column. the separation was performed by a linear gradient of acetonitrile and w ... | 1998 | 9498665 |
| development of fish mercury concentrations in finnish reservoirs from 1979 to 1994. | mercury (hg) concentrations in burbot (lota lota), perch (perca fluviatilis), northern pike (esox lucius), roach (rutilus rutilus), whitefish (coregonus lavaretus) and peled (c. peled) were monitored in 18 reservoirs situated in western and northern finland over a period of 16 years (1979-1994). the reservoirs were impounded from 1964 to 1980. the surface areas ranged between 1 and 417 km2. data from downstream sites and reference lakes were compared to reservoir mercury data. generally, fish hg ... | 1998 | 9652133 |
| expression of the vitellogenin gene in the liver of juvenile whitefish (coregonus lavaretus l. s.l.) exposed to effluents from pulp and paper mills. | juvenile whitefish (coregonus lavaretus l. s.l.) were exposed by caging in the field to diluted effluents from three operating pulp, paper, and paperboard mills in southern lake saimaa, finland. the expression of the vitellogenin gene, used as a biomarker of estrogenic contamination of effluents, was measured using a northern blotting method. increased mrna levels, the most specific and reliable evidence for estrogen receptor-mediated actions in vivo, were found in fish caged in the vicinity of ... | 1999 | 10375415 |
| the influence of food competition and host specificity on the transmission of triaenophorus crassus (cestoda) and cystidicola farionis (nematoda) to coregonus lavaretus and coregonus albula (pisces:coregonidae) in finland. | as a superior competitor for planktonic food, vendace (coregonus albula), when abundant, is expected to displace whitefish (coregonus lavaretus) from feeding on plankton and to force it to rely more on benthic food. the predicted result would be a reduced abundance of the copepod-transmitted cestode triaenophorus crassus in whitefish, but an increase in the abundance of the nematode cystidicola farionis transmitted via benthic amphipods. we studied the occurrence of both parasites in whitefish d ... | 1999 | 10616921 |
| effect of triaenophorus crassus (cestoda) infection on behavior and susceptibility to predation of the first intermediate host cyclops strenuus (copepoda). | some parasites have been shown to manipulate host behavior so that parasite transmission to the next host is enhanced. infection with triaenophorus crassus forel (cestoda) caused alterations in the activity and microhabitat selection of the first intermediate host cyclops strenuus fischer (copepoda) in the laboratory. infected copepods made more starts to swim but spent less time swimming than uninfected copepods. these changes were independent of the intensity of infection. in a water column il ... | 2000 | 10958437 |
| eox and organochlorine compounds in fish and ringed seal samples from lake ladoga, russia. | information about the pollution of lake ladoga, the largest lake in europe, has been controversial. various effluents and drainage waters affect the quality of the lake water. wastewaters have caused eutrophication of parts of lake ladoga, but concentrations of persistent organic pollutants in the lake's food webs are poorly understood. in this study, concentrations of some organochlorine compounds, chlorophenols (cps), and extractable organic halogen (eox) were determined in smelt (osmerus eper ... | 2000 | 11057612 |
| [the morphological variability of the maritae of phyllodistomum umblae and phyllodistomum folium (trematoda: gorgoderidae) from fish in the lake baikal basin]. | the host variability of adults of phyllodistomum umblae and p. folium in fishes of the baikal region has been studied. the absence of considerable geographical variability of p. umblae in coregonus lavaretus (lake baikal, lake storsjön in sweden) has been shown. the complexes of most stable (the size of acetabulum and eggs, location of acetabulum, ovary and vitelline bodies) and variable (the distance from oral sucker to intestinal bifurcation, distance from intestinal back edge to body end, wid ... | 2000 | 11060890 |
| presence of planktothrix sp. and cyanobacterial toxins in lake ammersee, germany and their impact on whitefish (coregonus lavaretus l.). | due to the increasing oligotrophy of lake ammersee, southern germany, metalimnic planktothrix have become one of the dominant planktonic species causing regular blooms. whitefish (coregonus lavaretus) is the dominant local fish species with great importance for the fishing industry. recently, whole age groups of this fish species have disappeared and since 1991, average body-weight has decreased. the causes for this remain unclear. planktothrix species produce the cyclic peptide toxin desmethyl ... | 2001 | 11769245 |
| fish status survey of nordic lakes: effects of acidification, eutrophication and stocking activity on present fish species composition. | the status of fish populations in 3821 lakes in norway, sweden and finland was assessed in 1995-1997. the survey lakes were chosen by stratified random sampling from all (126 482) fennoscandian lakes > or = 0.04 km2. the water chemistry of the lakes was analyzed and information on fish status was obtained by a postal inquiry. fish population losses were most frequent in the most highly acidified region of southern norway and least common in eastern fennoscandia. according to the inquiry results, ... | 2003 | 12733793 |
| the effect of dietary phosphorus deficiency on the immune responses of european whitefish (coregonus lavaretus l.). | low phosphorous (p) feeds in aquaculture are recommended to reduce eutrophication of water systems. however, the feed should be adequate for normal growth and intact immune defence. influence of low dietary p supply on non-specific and specific immune defence of european whitefish (coregonus lavaretus) was studied in two trials. for trial 1, a semi-purified, low-p diet was formulated and supplied with 0, 2.5, 5.0, 7.5, or 10.0 g p kg(-1)to obtain a p gradient of 4.4-14.9 g kg(-1)diet. diets were ... | 2003 | 12834619 |
| prevalence of listeria monocytogenes in, and microbiological and sensory quality of, rainbow trout, whitefish, and vendace roes from finnish retail markets. | the prevalence of listeria monocytogenes in retail roe, as well as the microbiological and sensory qualities of the roe, were studied for three fish species under three different storage conditions. a total of 147 finnish rainbow trout (oncorhynchus mykiss), whitefish (coregonus lavaretus), vendace (coregonus albula), and burbot (lota lota) roe samples were bought fresh, frozen, or frozen-thawed from finnish retail markets. the overall prevalence of l. monocytogenes was 5%; however, the prevalen ... | 2003 | 14572220 |
| investigation of wild caught whitefish, coregonus lavaretus (l.), for infection with viral haemorrhagic septicaemia virus (vhsv) and experimental challenge of whitefish with vhsv. | abstract one hundred and forty-eight wild whitefish, coregonus lavaretus (l.), were caught by electrofishing and sampled for virological examination in december 1999 and 2000, during migration from the brackish water feeding grounds to the freshwater spawning grounds, where the whitefish may come into contact with farmed rainbow trout. all samples were examined on cell cultures. no viruses were isolated. three viral haemorrhagic septicaemia virus (vhsv) isolates of different origin were tested i ... | 2004 | 15228609 |
| helminth assemblages of whitefish (coregonus lavaretus) in interconnected lakes: similarity as a function of species specific parasites and geographical separation. | this article examined the composition of parasite assemblages of whitefish (coregonus lavaretus) in 8 interconnected lakes in northeastern finland and evaluated the role of coregonid specific parasites and the geographical distance between populations in determining the similarity of the assemblages. parasite assemblages were compared using the jaccard qualitative similarity index and a quantitative similarity index and by incorporating the allogenic-autogenic species concept and the effects of ... | 2004 | 15270087 |
| echinorhynchus salmonis müller, 1784 (acanthocephala: echinorhynchidae) from the bothnian bay, baltic sea: morphological variability and radial asymmetry of proboscis hooks. | echinorhynchus salmonis is a common parasite of salmoniform and other fishes, occurring in fresh and brackish waters throughout the holarctic. presented here is the first analysis of the morphometric and meristic variation in a palaearctic population of e. salmonis, collected from whitefish coregonus lavaretus l. and smelt osmerus eperlaus (l.) from the bothnian bay, northern baltic sea. morphological data were compared with published descriptions of congeneric taxa. nearctic populations of salm ... | 2004 | 15449830 |
| toward adaptive management: the impacts of different management strategies on fish stocks and fisheries in a large regulated lake. | we applied the adaptive management approach to analyze the demand and feasibility of adaptive management of fish stocks in a large regulated lake, oulujärvi, in northern finland. the process consisted of four phases: (1) analysis of the current state of the fisheries system (fishers, related markets and industry, fisheries researches and authorities, related organizations, etc.); (2) analysis of the objectives of different stakeholders; (3) the composition of alternative management strategies an ... | 2004 | 15517682 |
| [parasite fauna in salmonidean fishes from the paanaiarvi-olanga lake-river system]. | the data on parasite fauna in the brown trout salmo trutta, white fish coregonus lavaretus, and grayling thymall thymallus from the paanajarvi-olanga lake-river system (white sea basin) are presented. as like-river systems in this area remain in natural conditions, without any anthropogenic pressure, the parasite fauna in salmonoideans from these water bodies had not been changed and has an archetypical state. the parasite fauna core is established in fishes aged 3+. parasite species forming the ... | 2005 | 15810556 |
| morphological divergence and origin of sympatric populations of european whitefish (coregonus lavaretus l.) in lake femund, norway. | combining morphological and genetic analysis, we compared patterns of diversification within and between morphs among sympatric european whitefish (coregonus lavaretus l.) populations in lake femund, norway. seven external populations, from potential colonization routes into lake femund were included. we found that deep-, shallow-, river- and bay spawning populations are distinct morphs in lake femund. within morphs, populations range from being similar genetically (fst=0-0.005) among deep-spawn ... | 2005 | 15842498 |
| histopathology, ultrastructure and immunohistochemistry of coregonus lavaretus hearts naturally infected with ichthyocotylurus erraticus (trematoda). | histopathological, ultrastructural and immunohistochemical investigations were conducted on 26 specimens of powan coregonus lavaretus (l.) from loch lomond (scotland). the hearts of all 26 powan (15 females and 11 males) investigated harboured metacercariae of the digenean trematode ichthyocotylurus erraticus (rudolphi, 1809). the vast majority of metacercariae were located either singly or as an aggregation of white cysts on the surface of the bulbus arteriosus. the intensity of infection range ... | 2005 | 16261940 |
| oral toxicity of the microcystin-containing cyanobacterium planktothrix rubescens in european whitefish (coregonus lavaretus). | the microcystin-producing cyanobacterium planktothrix is one of the most widespread genera amongst toxin producing cyanobacteria in european lakes. in particular, the metalimnic blooms of planktothrix rubescens have been associated with growing problems in the professional freshwater fishery as a decrease in yearly yields in the important coregonids fishery often coincides with the appearance of p. rubescens. p. rubescens is a cyanobacterial species known to produce toxic compounds, e.g. microcy ... | 2006 | 16806524 |
| the parasite fauna of brown trout salmo trutta, white fish coregonus lavaretus, and grayling thymallus thymallus from water bodies of north karelia (russia). | the data on parasite fauna of brown trout salmo trutta, whitefish coregonus lavaretus, and grayling thymallus thymallus from lake-river system paanajarvi-olanga (white sea basin) are presented. as lake-river systems on this area remain in natural conditions, without any anthropogenic pressure, the parasite fauna of salmonidae in these water bodies had not been changed and has an archetypal status. | 2004 | 16865973 |
| parasite fauna of selected fish species of lake miedwie. | a total of 136 fishes, representing 9 species (perch, perca fluviatilis l.; pike, esox lucius l.; european eel, anguilla anguilla (l.); common bream, abramis brama (l.); roach, rutilus rutilus (l.); tench tinca tinca (l.); european whitefish, coregonus lavaretus (l.); vendace, coregonus albula (l.); and zander, sander lucioperca (l.)), from lake miedwie were studied within 1997-1999. the necropsies yielded 41 parasite species (taxa). the most diversified were parasite faunas of pike (19 parasite ... | 2002 | 16888943 |
| parallel evolution of ecomorphological traits in the european whitefish coregonus lavaretus (l.) species complex during postglacial times. | the extensive phenotypic polymorphism in the european whitefish has triggered evolutionary research in order to disentangle mechanisms underlying diversification. to illuminate the ecological distinctiveness in polymorphic whitefish, and evaluate taxonomic designations, we studied nine norwegian lakes in three watercourses, which each harboured pairs of divergent whitefish morphs. we compared the morphology and life history of these morphs, documented the extent of genetic differentiation betwee ... | 2006 | 17054498 |
| influence of climate variability on whitefish (coregonus lavaretus) year-class strength in a deep, warm monomictic lake. | the year-class strength (ycs) of blaufelchen (coregonus lavaretus) in deep upper lake constance was analysed for a 52-year period, from 1947 to 1998. despite strong anthropogenic influences on the species' population dynamics due to cultural eutrophication and oligotrophication, intense fishing, and large-scale stocking, the influence of climate variability associated with the north atlantic oscillation (nao) is apparent in the data set. this influence is significant although large-scale stockin ... | 2007 | 17109176 |
| physiological stress and pathology in european whitefish (coregonus lavaretus) induced by subchronic exposure to environmentally relevant densities of planktothrix rubescens. | planktothrix rubescens belongs to the most ubiquitous cyanobacterial species in mesotrophic and oligotrophic lakes in the pre-alpine regions. in most of these lakes, coregonids are among the dominant species of the ichthyofauna with great importance for the professional fishery. a possible link between the occurrence of toxic planktothrix blooms and the recurrent slumps in coregonid yields has been suggested. indeed, acute toxic effects of microcystins and other cyanobacterial toxins have been s ... | 2007 | 17320197 |
| selected pathological, immunohistochemical and ultrastructural changes associated with an infection by diphyllobothrium dendriticum (nitzsch, 1824) (cestoda) plerocercoids in coregonus lavaretus (l.) (coregonidae). | the pathological changes induced by an infection of diphyllobothrium dendriticum (nitzsch, 1824) plerocercoids in powan, coregonus lavaretus (l.), from loch lomond, scotland, were assessed using immunohistochemical and ultrastructural techniques. in a sample of 26 powan, the occurrence of encysted plerocercoids of d. dendriticum on the outer surface of the stomach was 38.5% (n = 10) with the number of cysts ranging from 4 to 15 and measuring 4.2 +/- 1.0 mm x 3.4 +/- 0.9 mm (mean +/- sd). histolo ... | 2007 | 17640250 |
| lack of circadian regulation of in vitro melatonin release from the pineal organ of salmonid teleosts. | in many teleost species, the photoreceptive pineal organ harbors the circadian clock that regulates melatonin release in the pineal organ itself. however, the pineal organ of three salmonids (rainbow trout oncorhynchus mykiss, masu salmon oncorhynchus masou, and sockeye salmon oncorhynchus nerka) did not exhibit circadian rhythms in melatonin release when maintained under constant darkness (dd) in vitro, suggesting that the pineal organs of all salmonids lack the circadian regulation of melatoni ... | 2007 | 17681505 |
| [comparative study of bile-acid composition in the bile of the european vendace coregonus albula l. and whitefish coregonus lavaretus l. under conditions of technogenic water pollution]. | changes of the bile acid composition were studied in bile of the vendace coregonus albula l. and the whitefish coregonus lavaretus l. under effect of sewers of an ore mining and processing plant, the main pollutin agents of the sewers being heavy metals. the revealed variability of the bile acid composition indicates different species-related sensitivity to the studied pollutants as well as a lower resistance of males as compared with females to this type of pollution. mechanisms of effects of i ... | 2007 | 18038637 |
| genetic differentiation among european whitefish ecotypes based on microsatellite data. | the amount of genetic differentiation at dna microsatellite loci in european whitefish (coregonus lavaretus) was assessed among ecotypes, populations and run-timing types. the magnitude of genetic changes potentially caused by hatchery broodstock rearing were also compared with those observed in corresponding natural populations. a total of 35 populations were studied, including 33 coregonus lavaretus populations and two samples of coregonus peled. five of the six whitefish ecotypes in finland w ... | 2008 | 18503709 |
| human-induced changes in the reproductive traits of lake constance common whitefish (coregonus lavaretus). | size-selective fishery harvest leads to phenotypic changes in fish reproductive traits. when these changes represent an evolutionary response of a stock, they may have severe consequences for future stock dynamics and yields. in freshwater ecosystems, reproductive traits may also be affected by other human impacts such as changes in system productivity. the present study uses regression analysis to evaluate the impacts of changes in lake trophy and of an intensive size-selective harvest over sev ... | 2009 | 19127609 |
| internal exposure of whitefish (coregonus lavaretus) to estrogens. | gonad malformations have been found in fish all over the world. particularly in lake thun (switzerland) a high prevalence of gonad deformations in whitefish has been observed. very often, a link between exposure to endocrine disrupting compounds and altered gonad morphology exists. hence, we analyzed the estrogenic burden in bile and muscle from whitefish (coregonids) from lake thun and linked it to observed gonad malformations. estrogenicity in bile, measured with the yeast estrogen screen (yes ... | 2009 | 19477536 |
| rapid parallel adaptive radiations from a single hybridogenic ancestral population. | the alpine lake whitefish (coregonus lavaretus) species complex is a classic example of a recent radiation, associated with colonization of the alpine lakes following the glacial retreat (less than 15 kyr bp). they have formed a unique array of endemic lake flocks, each with one to six described sympatric species differing in morphology, diet and reproductive ecology. here, we present a genomic investigation of the relationships between and within the lake flocks. comparing the signal between ov ... | 2011 | 20685705 |
| identification of cryptosporidium species in fish from lake geneva (lac léman) in france. | cryptosporidium, a protozoan parasite that can cause severe diarrhea in a wide range of vertebrates including humans, is increasingly recognized as a parasite of a diverse range of wildlife species. however, little data are available regarding the identification of cryptosporidium species and genotypes in wild aquatic environments, and more particularly in edible freshwater fish. to evaluate the prevalence of cryptosporidiumspp. in fish from lake geneva (lac léman) in france, 41 entire fish and ... | 2015 | 26213992 |
| prevalence of diphyllobothrium latum (cestoda: diphyllobothriidae) plerocercoids in fish species from four italian lakes and risk for the consumers. | in recent years there has been a re-emergence of diphyllobothriasis by diphyllobothrium latum (cestoda: diphyllobothriidae) in italy, france and switzerland, where in the past this fish-borne zoonosis was widespread and then virtually disappeared. a change in eating habits such as the consumption of raw/undercooked freshwater fish, has led to an increased risk for consumers of ingesting infective larvae of d. latum. a survey on the factors responsible for the re-emergence of human diphyllobothri ... | 2016 | 27491055 |
| [morphological variability of proteocephalus percae (müller 1780) parasitizing coregonid fishes]. | morphological variability of proteocephalus percae from native host--perch perca fluviatilis and two species of coregonids (whitefish coregonus lavaretus and arctic cisco c. autumnalis) from fish farms of karelia were studied. parasite groups from 3 host species differed by morphometric parameters. morphological structure of p. percae from native host included three morphs, those numbers were almost equal. parasite groups of whitefish and arctic cisco differed from that of perch in morphological ... | 2015 | 26373190 |
| genetic diversity of diplomonadida in fish of the genus coregonus from southeastern siberia. | diplomonadida are primitive flagellate protozoa, among which both commensals and pathogens have been recorded. to date, members of the genera hexamita and spironucleus have been reported in the digestive system of fish in the baikal region. we determined the genetic diversity of diplomonadida in fish of the genus coregonus from south-eastern siberia using molecular-genetic methods. fish for analysis were caught in lake baikal and in the barguzin, nepa, chechuy, and kirenga rivers from 2010 to 20 ... | 2016 | 27078653 |
| infection levels of plerocercoids of the tapeworm triaenophorus crassus and feeding strategy in two fish species from the ultra-oligotrophic lake achensee, austria. | thus far, high burdens of triaenophorus crassus plerocercoids have been reported only in old age groups of coregonid and salmonid fishes. here we show heavy infection with t. crassus in young whitefish coregonus lavaretus in the ultra-oligotrophic and regulated achensee in tyrol, austria. prevalence of t. crassus on c. lavaretus was 100% in all age groups and abundance significantly increased with fish age. the mean annual accumulation of t. crassus was 5.2 parasites in 0- to 7-year-old c. lavar ... | 2016 | 25345803 |
| eye fluke-induced cataracts in natural fish populations: is there potential for host manipulation? | manipulation of host phenotype (e.g. behaviour, appearance) is suggested to be a common strategy to enhance transmission in trophically transmitted parasites. however, in many systems, evidence of manipulation comes exclusively from laboratory studies and its occurrence in natural host populations is poorly understood. here, we examined the potential for host manipulation by diplostomum eye flukes indirectly by quantifying the physiological effects of parasites on fish. earlier laboratory studie ... | 2011 | 20800013 |
| predation by signal crayfish pacifastacus leniusculus on fish eggs and its consequences for coregonid recruitment. | the character and magnitude of predation by the invasive, ectothermic pacifastacus leniusculus, a crayfish widely introduced to europe and japan from north america, on the eggs of coregonid fishes, vendace coregonus albula and whitefish coregonus lavaretus were examined by experimentation, modelling and field data. the present results showed that p. leniusculus has the potential to be very efficient predator of fish eggs under winter conditions, but the predation by p. leniusculus did not signif ... | 2015 | 25605004 |
| speciation reversal in european whitefish (coregonus lavaretus (l.)) caused by competitor invasion. | invasion of exotic species has caused the loss of biodiversity and imparts evolutionary and ecological changes in the introduced systems. in northern fennoscandia, european whitefish (coregonus lavaretus (l.)) is a highly polymorphic species displaying adaptive radiations into partially reproductively isolated and thus genetically differentiated sympatric morphs utilizing the planktivorous and benthivorous food niche in many lakes. in 1993, lake skrukkebukta was invaded by vendace (coregonus alb ... | 2014 | 24626131 |
| species introduction promotes hybridization and introgression in coregonus: is there sign of selection against hybrids? | species introductions are considered one of the major drivers of biodiversity loss via ecological interactions and genetic admixture with local fauna. we examined two well-recognized fish species, native whitefish (coregonus lavaretus) and introduced vendace (coregonus albula), as well as their morphological hybrids in a single lake to test for selection against hybrids and backcrosses in the wild. a representative random subsample of 693 individuals (27.8%) was taken from the total catch of cor ... | 2011 | 21831252 |
| [microevolutionary aspects of morphological variability and specificity of cestodes by the example of proteocephalus longicollis (zeder, 1800) (proteocephalidae), a parasite of coregonids]. | morphological variability of the cestode proteocephalus longicollis from the smelt osmerus eperlanus l., which was spontaneously introduced into the syamozero lake, has been studied. it was established that p. longicollis became an abundant element of the smelt parasite fauna during last 20 years, thereby showing the absence of host specificity. it was revealed that morphological polymorphism of p. longicollis from smelt combines features of ecological forms characteristic for aboriginal host sp ... | 2010 | 20795485 |
| candidate genes and adaptive radiation: insights from transcriptional adaptation to the limnetic niche among coregonine fishes (coregonus spp., salmonidae). | in the past 40 years, there has been increasing acceptance that variation in levels of gene expression represents a major source of evolutionary novelty. gene expression divergence is therefore likely to be involved in the emergence of incipient species, namely, in a context of adaptive radiation. in the lake whitefish species complex (coregonus clupeaformis), previous microarray experiments have led to the identification of candidate genes potentially implicated in the parallel evolution of the ... | 2009 | 18927090 |
| localization of 5s rrna loci in three coregonid species (salmonidae). | in the present study the chromosome distribution of the 5s rdna loci and its relation to the major rdna genes were investigated in three coregonid species (salmonidae): coregonus lavaretus, coregonus peled and coregonus albula, a family which has experienced large karyotype rearrangements along its evolution starting from a tetraploid ancestor. 5s prins/cma3 sequential staining together with previous data enabled us to locate 5s rrna genes and nucleolar organizer regions (nors) in the three spec ... | 2003 | 14620957 |
| ribosomal genes in coregonid fishes (coregonus lavaretus, c. albula and c. peled) (salmonidae): single and multiple nucleolus organizer regions. | major rdna loci, i.e. nucleolus-organizing regions (nors), were assigned using chromomycin-a3 (cma3) staining followed by sequential silver (ag) staining and in situ hybridization (ish) with a rdna probe to the chromosomes of the european whitefish (coregonus lavaretus), the peled (coregonus peled) and the vendace (coregonus albula), three closely related coregonine salmonid fishes. one pair of nor-bearing chromosomes was found in the peled karyotype. multichromosomal, but stable, locations of r ... | 2001 | 11903562 |
| rrna genes map to chromosomes 10, 11 and 12 in european whitefish (coregonus lavaretus) and to chromosomes 1, 5, 9 and 10 in vendace (coregonus albula). | | 2000 | 10997787 |
| resource partitioning in food, space and time between arctic charr (salvelinus alpinus), brown trout (salmo trutta) and european whitefish (coregonus lavaretus) at the southern edge of their continuous coexistence. | arctic charr and european whitefish are considered to be strong competitors in lakes, with the latter usually being the superior species. however, high niche plasticity and lake morphometry may suggestively facilitate resource partitioning and coexistence between charr and whitefish. here, we explore the trophic niche utilization (diet and habitat use) of charr and whitefish co-occurring with brown trout in the deep and oligotrophic lake fyresvatnet, southern norway (59°05'n, 8°10'e). using cpue ... | 2017 | 28122061 |
| tolerance of whitefish (coregonus lavaretus) early life stages to manganese sulfate is affected by the parents. | european whitefish (coregonus lavaretus) embryos and larvae were exposed to 6 different manganese sulfate (mnso4 ) concentrations from fertilization to the 3-d-old larvae. the fertilization success, offspring survival, larval growth, yolk consumption, embryonic and larval mn tissue concentrations, and transcript levels of detoxification-related genes were measured in the long-term incubation. a full factorial breeding design (4 females × 2 males) allowed examination of the significance of both f ... | 2016 | 27791289 |
| potassium ions in extender differentially influence the post-thaw sperm motility of salmonid fish. | potassium ions are known to have an inhibitory effect on the sperm motility of salmonids. for this reason, the addition of k(+) to the extender is frequently applied. however, the effect of the addition of k(+) to the extender has not yet been tested. the aim of this study was to test the influence of potassium ion supplementation of the extender on the sperm motility parameters from five salmonidae species (rainbow trout (oncorhynchus mykiss), sex-reversed female rainbow trout, whitefish (coreg ... | 2016 | 27404573 |
| illumina sequencing reveals aberrant expression of micrornas and their variants in whitefish (coregonus lavaretus) liver after exposure to microcystin-lr. | molecular analyses show that challenging fish with microcystin-lr (mc-lr) causes perturbations of microrna (mirna) signaling. however, the significance and scope of these alterations is currently unknown. to address this issue, we studied mirna gene expression in the liver of juvenile whitefish, c. lavaretus, during 28 days of exposure to a subacute dose of mc-lr (100 μg·kg-1 body mass). using genomic resources of atlantic salmon (agkd03), the mature mirna library of atlantic salmon (mirbase-21) ... | 2016 | 27391076 |
| weighted species richness outperforms species richness as predictor of biotic resistance. | the species richness hypothesis, which predicts that species-rich communities should be better at resisting invasions than species-poor communities, has been empirically tested many times and is often poorly supported. in this study, we contrast the species richness hypothesis with four alternative hypotheses with the aim of finding better descriptors of invasion resistance. these alternative hypotheses state that resistance to invasions is determined by abiotic conditions, community saturation ... | 2016 | 27008794 |
| inter and intra-population phenotypic and genotypic structuring in the european whitefish coregonus lavaretus, a rare freshwater fish in scotland. | this study revealed between-lake genetic structuring between coregonus lavaretus collected from the only two native populations of this species in scotland, u.k. (lochs eck and lomond) evidenced by the existence of private alleles (12 in lomond and four in eck) and significant genetic differentiation (fst = 0·056) across 10 microsatellite markers. juvenile c. lavaretus originating from eggs collected from the two lakes and reared in a common-garden experiment showed clear phenotypic differences ... | 2016 | 26748995 |
| mir-34a and bcl-2 expression in whitefish (coregonus lavaretus) after microcystin-lr exposure. | studies on mammals have demonstrated that the expression of mir-34a is associated with process of apoptosis in many cell types, by lowering expression of the anti-apoptotic protein bcl-2. despite the role of mir-34a, there is no data about the mir-34a:bcl-2 interaction in lower vertebrates, especially in fish. in the current study, we determined the nucleotide sequence of mir-34a precursor, predicted its secondary structure, and shed light on the potential role of p53 in activation of mir-34a in ... | 2016 | 26691544 |
| effects of origin and season on the lipids and sensory quality of european whitefish (coregonus lavaretus). | the effect of variation in origin and season on the lipids and sensory quality of european whitefish (coregonus lavaretus) was studied. the proportion of docosahexaenoic acid (22:6n-3) of the total phospholipid fatty acids in fillets was considerably higher in spring compared with autumn. farmed fish contained 3-4 times more lipids than wild fish. combined, the fillets of farmed fish contained 2-3 times more eicosapentaenoic acid (20:5n-3) and docosahexaenoic acid than the fillets of wild fish. ... | 2016 | 26675838 |
| male investments in high quality sperm improve fertilization success, but may have negative impact on offspring fitness in whitefish. | many ejaculate traits show remarkable variation in relation to male social status. males in disfavoured (subordinate) mating positions often invest heavily on sperm motility but may have less available resources on traits (e.g., secondary sexual ornaments) that improve the probability of gaining matings. although higher investments in sperm motility can increase the relative fertilization success of subordinate males, it is unclear whether status-dependent differences in sperm traits could have ... | 2015 | 26389594 |
| the natural history of echinorhynchus bothniensis zdzitowiecki and valtonen, 1987 (acanthocephala) in a high arctic lake. | the acanthocephalan echinorhynchus bothniensis zdzitowiecki and valtonen, 1987 differs from most other species in the genus echinorhynchus zoega in müller, 1776 by infecting mysids (order mysida) instead of amphipods (order amphipoda) as intermediate hosts. here we report on the occurrence of e. bothniensis in mysids (mysis segerstralei audzijonytė et väinölä) and in its fish definitive hosts in a high arctic lake. out of 15 907 sampled mysids, 4.8% were infected with a mean intensity of 1.05 wo ... | 2015 | 26373432 |
| mir-122-5p as a plasma biomarker of liver injury in fish exposed to microcystin-lr. | recent studies have shown the presence of large amounts of micrornas (mirnas; mirs) from damaged cells in the peripheral blood. in this study, we investigated the levels of mirnas circulating in the blood plasma of whitefish (coregonus lavaretus) after exposure to microcystin-lr. we used real-time pcr to examine the relative expression of plasma levels of 4 mirnas (mir-122-5p and let-7c-5p, the liver-enriched micrornas, mir-148a-3p which promotes the hapatospecific phenotype in mammals, and mir- ... | 2016 | 26345281 |
| c-myc in whitefish (coregonus lavaretus): structure, expression, and insights into possible posttranscriptional regulatory mechanism. | c-myc has a crucial function in growth control, differentiation, and apoptosis of vertebrate cells. despite the important role of c-myc in mediating the biological effects, studies of c-myc gene expression and factors that control it in organisms other than mammals, such as fish, have been rare. in the current study, we asked whether c-myc mrna of whitefish, a feasible organism for pollution monitoring in aquatic systems and a model in toxicological research, contains activity sites for regulato ... | 2015 | 25995172 |
| generation of a neutral fst baseline for testing local adaptation on gill raker number within and between european whitefish ecotypes in the baltic sea basin. | divergent selection at ecologically important traits is thought to be a major factor driving phenotypic differentiation between populations. to elucidate the role of different evolutionary processes shaping the variation in gill raker number of european whitefish (coregonus lavaretus sensu lato) in the baltic sea basin, we assessed the relationships between genetic and phenotypic variation among and within three whitefish ecotypes (sea spawners, river spawners and lake spawners). to generate exp ... | 2015 | 25877003 |
| double-digest rad sequencing using ion proton semiconductor platform (ddradseq-ion) with nonmodel organisms. | research in evolutionary biology involving nonmodel organisms is rapidly shifting from using traditional molecular markers such as mtdna and microsatellites to higher throughput snp genotyping methodologies to address questions in population genetics, phylogenetics and genetic mapping. restriction site associated dna sequencing (rad sequencing or radseq) has become an established method for snp genotyping on illumina sequencing platforms. here, we developed a protocol and adapters for double-dig ... | 2015 | 25808755 |
| adaptive radiation along a thermal gradient: preliminary results of habitat use and respiration rate divergence among whitefish morphs. | adaptive radiation is considered an important mechanism for the development of new species, but very little is known about the role of thermal adaptation during this process. such adaptation should be especially important in poikilothermic animals that are often subjected to pronounced seasonal temperature variation that directly affects metabolic function. we conducted a preliminary study of individual lifetime thermal habitat use and respiration rates of four whitefish (coregonus lavaretus (l. ... | 2014 | 25405979 |
| identification and de novo sequencing of housekeeping genes appropriate for gene expression analyses in farmed maraena whitefish (coregonus maraena) during crowding stress. | maraena whitefish (coregonus maraena; synonym coregonus lavaretus f. balticus) is a high-quality food fish in the southern baltic sea belonging to the group of salmonid fishes. coregonus sp. is successfully kept in aquaculture throughout northern europe (e.g. in finland, germany, russia) and north america. in this regard, the molecular and immunological characterisation of stress response in maraena whitefish contributes to the development of robust and fast-growing maraena whitefish breeding st ... | 2015 | 25249196 |
| fish consumption as a source of human exposure to perfluorinated alkyl substances in italy: analysis of two edible fish from lake maggiore. | extensive screening analyses of perfluorooctane sulfonate and related perfluorinated compounds (pfcs) in biota samples from all over the world have identified pfcs as global pollutants and have shown their bioaccumulation into higher trophic levels in the food chain. perfluorooctanoic acid (pfoa) and perfluorooctane sulfonate (pfos) are environmental contaminants belonging to a chemical group known as perfluorinated compounds. pfos and pfoa are very persistent in the environment and bioaccumulat ... | 2014 | 25113200 |
| metabolic enzymes activity and histomorphology in the liver of whitefish (coregonus lavaretus l.) and pike (esox lucius l.) inhabiting a mineral contaminated lake. | the effects of wastewater from a mining and ore-dressing mill on fish in lake kostomukshskoe, which is used as a cesspool of circulating water and for storage of industrial wastes produced by the kostomuksha mining and ore-dressing mill in northwest russia, were studied. the lake is characterized by heavy mineralization, high ph, elevated levels of k(+), li(+), so4 (2-), no(2-), cl(-), li, mn, and ni, and the presence of a fine-dispersed mechanical suspension. to assess the impact of contaminati ... | 2014 | 24865502 |
| phenotype-environment association of the oxygen transport system in trimorphic european whitefish (coregonus lavaretus) populations. | replicated adaptive radiation events, typified by phenotypic divergence across resource axes, provide important insight into the eco-evolutionary dynamics that lead to the formation of new species. here, we show that in trimorphic adaptive radiations of european whitefish (coregonus lavaretus), divergence of the oxygen transport system has occurred across the pelagic/littoral (shallow)-profundal (deep) resource axis, and at multiple biological scales. profundal whitefish exhibited significantly ... | 2014 | 24766154 |
| dual fuels: intra-annual variation in the relative importance of benthic and pelagic resources to maintenance, growth and reproduction in a generalist salmonid fish. | ecological systems are often characterized as stable entities. however, basal productivity in most ecosystems varies between seasons, particularly in subarctic and polar areas. how this variability affects higher trophic levels or entire food webs remains largely unknown, especially in these high-latitude regions. we undertook a year-long study of benthic (macroinvertebrate) and pelagic (zooplankton) resource availability, along with short (day/days: stomach content)-, medium (month: liver δ(13) ... | 2014 | 24738779 |
| lake morphometry and resource polymorphism determine niche segregation between cool- and cold-water-adapted fish. | climate change is increasing ambient temperatures in arctic and subarctic regions, facilitating latitudinal range expansions of freshwater fishes adapted to warmer water temperatures. the relative roles of resource availability and interspecific interactions between resident and invading species in determining the outcomes of such expansions has not been adequately evaluated. ecological interactions between a cool-water adapted fish, the perch (perca fluviatilis), and the cold-water adapted euro ... | 2014 | 24669746 |
| adhesion mechanisms in european whitefish coregonus lavaretus eggs: is this a survival mechanism for high-energy spawning grounds? | this study examined the potential biochemical and mechanical structures that may contribute to egg adhesion in european whitefish coregonus lavaretus. experiments showed that eggs from a population of c. lavaretus from loch eck remained non-adhesive in a solution chemically similar to ovarian fluid but became adhesive seconds after contact with water. examination of the ultrastructure of the chorion showed that the morphology changed significantly after contact with water, with nodule-like protu ... | 2013 | 24580664 |
| fish length exclusively determines sexual maturation in the european whitefish coregonus lavaretus species complex. | the probability that a fish matures at a certain age and length (the so-called probabilistic maturation reaction norm, pmrn) was analysed for a european whitefish coregonus lavaretus species complex population living in the austrian pre-alpine lake irrsee. fish length was found to be the only relevant determinant of maturation probability, and females matured at slightly smaller sizes than males. | 2014 | 24498908 |
| ecological speciation in postglacial european whitefish: rapid adaptive radiations into the littoral, pelagic, and profundal lake habitats. | understanding how a monophyletic lineage of a species diverges into several adaptive forms has received increased attention in recent years, but the underlying mechanisms in this process are still under debate. postglacial fishes are excellent model organisms for exploring this process, especially the initial stages of ecological speciation, as postglacial lakes represent replicated discrete environments with variation in available niches. here, we combine data of niche utilization, trophic morp ... | 2013 | 24455129 |
| proteome variance differences within populations of european whitefish (coregonus lavaretus) originating from contrasting salinity environments. | variation in gene expression is an important component of the phenotypic differences observed in nature. gene expression variance across biological groups and environmental conditions has been studied extensively and has revealed specific genes and molecular mechanisms of interest. however, little is known regarding the importance of within-population gene expression variation to environmental adaptation. to address this issue, we quantified the proteomes of individuals of european whitefish (co ... | 2014 | 24406297 |
| parallel and non-parallel morphological divergence among foraging specialists in european whitefish (coregonus lavaretus). | parallel phenotypic evolution occurs when independent populations evolve similar traits in response to similar selective regimes. however, populations inhabiting similar environments also frequently show some phenotypic differences that result from non-parallel evolution. in this study, we quantified the relative importance of parallel evolution to similar foraging regimes and non-parallel lake-specific effects on morphological variation in european whitefish (coregonus lavaretus). we found evid ... | 2013 | 23789070 |
| evidence of a recent decline in river lamprey lampetra fluviatilis parasitism of a nationally rare whitefish coregonus lavaretus: is there a diamond in the ruffe gymnocephalus cernuus? | lamprey-induced scarring of the nationally rare coregonus lavaretus, a known host of a freshwater-resident population of european river lamprey lampetra fluviatilis, was found to have declined precipitously since the establishment of several non-native fishes in loch lomond. evidence presented in this study points to the possibility that l. fluviatilis in this lake may have altered its trophic ecology in response to the negative impact that non-native species, in particular ruffe gymnocephalus c ... | 2013 | 23639164 |
| effects of temperature and food supply on the growth of whitefish coregonus lavaretus larvae in an oligotrophic peri-alpine lake. | the relative roles of temperature and food availability on the seasonal and daily growth of whitefish coregonus lavaretus larvae were investigated in the oligotrophic peri-alpine lake annecy, france. during the spring from 2004 to 2007, surface water temperature and density of potential zooplankton prey were monitored, and 2688 larvae were caught and measured. in addition, the daily growth of 130 larvae was estimated retrospectively by investigating the microstructure of their otoliths. temperat ... | 2012 | 23020558 |
| cytogenetic biomarkers for the assessment of the influence of pollution on natural fish populations. | cytogenetic analysis methods were used to study the developing embryos of the following four coregonidae species: coregonus peled (gmelin), coregonus lavaretus (gmelin), coregonus nasus (pallas) and coregonus muksun (pallas). spawners of these species were selected from rivers and lakes of the tyumen region (russia) with different levels of pollution. the variability of the chromosomal aberration rate was analyzed during a monitoring period of more than 20 years. the level of chromosomal mutabil ... | 2012 | 22995782 |
| [specific features of the numbers and structure of the population of proteocephalus longicollis (zeder 1800) (cestoda: proteocephalidea)--a mass parasite of whitefish coregonus lavaretus l. under conditions of technogenic pollution of the water body]. | the numbers, age structure, and morphological variation of the cestode proteocephalus longicollis from whitefish of a natural water body (kamennoe lake) and those of kostomuksha lake polluted with wastes of the mining industry (northern karelia) have been studied. in the polluted water body, a high infestation of whitefish and domination of larval stages in the structure of the parasite population have been established. it is shown that under conditions of pollution, only one of the variations o ... | 2016 | 22988762 |
| ecological proteomics: finding molecular markers that matter. | it is becoming increasingly clear that local adaptation can occur even in the face of high gene flow and limited overall genomic differentiation among populations (reviewed by nosil et al. 2009). thus, one important task for molecular ecologists is to sift through genomic data to identify the genes that matter for local adaptation (hoffmann & willi 2008; stapley et al. 2010). recent advances in high-throughput molecular technologies have facilitated this search, and a variety of approaches can b ... | 2012 | 22953332 |
| expression profiling in vivo demonstrates rapid changes in liver microrna levels of whitefish (coregonus lavaretus) following microcystin-lr exposure. | at present, little is known about the role of mirnas in liver response of fish to the cyanobacterial hepatotoxin microcystin-lr (mc-lr) treatment, despite the fact that the exposure is thought to underlie multiple acute and chronic effects. to address this question, we used the real-time pcr method to examine the differential expression of 6 mirnas putatively playing roles in signal transduction (let-7c, mir-9b), apoptosis and cell cycle (mir-16a, mir-21a, mir-34a) and fatty acid metabolism (mir ... | 2012 | 22819808 |
| microsatellite genotyping of cryopreserved spermatozoa for the improvement of whitefish semen cryobanking. | the cryobanking of semen is recognized as an emerging tool for the conservation of fish biodiversity. microsatellite analysis of the dna of cryopreserved sperm would facilitate the assessment of genetic variability of cryobanked semen specimens. the aim of this study was to compare microsatellite profiles of dna extracted from adipose fins and cryopreserved semen collected from eleven male whitefish (coregonus lavaretus l.). the following microsatellite loci were employed: cocl-lav-8, cocl-lav-1 ... | 2012 | 22750203 |
| dietary ontogeny and niche shift to piscivory in lacustrine brown trout salmo trutta revealed by stomach content and stable isotope analyses. | the feeding ecology and ontogeny of a large size range of brown trout salmo trutta in lake fyresvatnet, southern norway, were examined by stomach content and stable isotope analyses. according to the stomach contents, the s. trutta changed their diet at c. 30 cm total length (l(t) ). the smaller size classes fed on benthic invertebrates and surface insects, whereas larger s. trutta (>30 cm) fed mainly on whitefish coregonus lavaretus. a similar, but more gradual shift to piscivory in the size ra ... | 2012 | 22650427 |
| short-term uptake of microcystin-lr by coregonus lavaretus: gst activity and genotoxicity. | in the present study, juvenile whitefish weighing 2 g were exposed by force-feeding to two ecologically relevant doses (0.05 and 0.5 μg per fish) of microcystin-lr (mc-lr). then over 96 h the mc uptake in fish liver and muscle was measured, as the activity of the detoxification enzyme glutathione s-transferase (gst) in the liver, and the genotoxicity impact on red blood cells. results show that (1) the mc-lr equivalent concentrations increased for both doses and in both organs of whitefish with ... | 2012 | 22539116 |
| mitogenome sequencing reveals shallow evolutionary histories and recent divergence time between morphologically and ecologically distinct european whitefish (coregonus spp.). | the advent of second-generation sequencing has made it possible to quickly and economically generate whole mitochondrial genome (mitogenome) sequences. to date, mitogenome studies of nonmodel organisms have demonstrated increased power for resolving interspecies relationships. we explored an alternate use of such data to recover relationships and population history of closely related lineages with a shallow evolutionary history. using a gs-flx platform, we sequenced 106 mitogenomes from the core ... | 2012 | 22509795 |
| a proteomics approach reveals divergent molecular responses to salinity in populations of european whitefish (coregonus lavaretus). | osmoregulation is a vital physiological function for fish, as it helps maintain a stable intracellular concentration of ions in environments of variable salinities. we focused on a primarily freshwater species, the european whitefish (coregonus lavaretus), to investigate the molecular mechanisms underlying salinity tolerance and examine whether these mechanisms differ between genetically similar populations that spawn in freshwater vs. brackishwater environments. a common garden experiment invol ... | 2012 | 22486940 |
| are phenotypic traits useful for differentiating among a priori coregonus taxa? | a key for three putative species apparently found in three geographic areas, i.e. coregonus clupeoides (in scotland), coregonus stigmaticus (in england), and coregonus pennantii (in wales) given in a recent review was tested quantitatively using 544 individuals from nine populations. the classification success of the key was very low (27%). it was concluded that there is currently no robust evidence for the recognition of the three putative species. furthermore, the use of phenotypic characters ... | 2012 | 22268437 |
| [catalytic characteristics of monoamine oxidase of whitefish coregonus lavaretus ludoga]. | study of substrate-inhibitory specificity of liver mitochondrial monoamine oxidase (mao) of sexually mature individuals of the whitefish coregonus lavaretus ludoga p. from the ladoga lake has revealed distinguished peculiarities of catalytical properties of this enzyme. the studied mao, on one hand, like the classical enzyme of homoiothermal animals, is able to deaminate tyramine, serotonin, benzylamine, tryptamine, and beta-phenylalanine, but, on the other hand, to deaminate histamine, the clas ... | 2011 | 21938908 |
| [comparative sensitivity of liver monoamine oxidases of frog and whitefish to some tricyclic compounds]. | there is performed a comparative analysis of action of four acridine derivatives and of one xanthene derivative (pyronine g) on activity of liver monoamine oxidase (mao) of two species of poikilothermal freshwater animals: a representative of amphibians--the common frog rana temnporaria and a representative of the order salmonidae--the european whitefish coregonus lavaretus. the studied synthetic hexamerous tricyclic compounds show the irreversible character of inhibition of intermediate potency ... | 2013 | 21469337 |
| heavy metal contents in whitefish (coregonus lavaretus) along a pollution gradient in a subarctic watercourse. | metallurgic industry is a source of serious environmental pollution related to the emission of heavy metals. freshwater systems are focal points for pollution, acting as sinks for contaminants that may end up in fish and humans. the pasvik watercourse in the border area between finland, norway and russia is located in the vicinity of the pechenganickel metallurgic enterprises, and the lower part of the watershed drains the nikel smelters directly through lake kuetsjarvi. heavy metal (ni, cu, cd, ... | 2011 | 21287264 |
| food selection of coregonus lavaretus in a brackish water ecosystem. | this study examined how variability in the abundance and biomass structure of benthic invertebrates affected the feeding choice of the whitefish coregonus lavaretus on a hard bottom habitat of the brackish baltic sea. in general, crustaceans such as idotea balthica and gammarus spp. were preferred over molluscs. although being the most numerous taxon in the invertebrate samples, mytilus trossulus was the lowest ranking in c. lavaretus food preference. the availability of benthic invertebrate pre ... | 2011 | 21284633 |
| has habitat heterogeneity promoted phenotypic and ecological sub-structuring among a coregonus lavaretus population in a large scottish lake? | differences in stable-isotope values, morphology and ecology in whitefish coregonus lavaretus were investigated between the three basins of loch lomond. the results are discussed with reference to a genetic investigation to elucidate any substructuring or spawning site fidelity. foraging fidelity between basins of loch lomond was indicated by δ¹³c and δ¹⁵n values of c. lavaretus muscle tissue. there was, however, no evidence of the existence of sympatric morphs in the c. lavaretus population. a ... | 2010 | 21155790 |
| quality and production trait genetics of farmed european whitefish, coregonus lavaretus. | we present here phenotypic and genetic parameters for the major quality and production traits of farmed european whitefish. a total of 70 families were produced by mating each of 45 sires to an average of 1.6 dams and each of the 52 dams to an average of 1.3 sires. a total of 2,100 individuals were recorded for survival, and 507 individuals for growth and quality-related traits. the 4 major results were as follows: first, all traits exhibited nonzero heritabilities except for fillet gaping and f ... | 2011 | 21097679 |
| elevated water temperature impairs fertilization and embryonic development of whitefish coregonus lavaretus. | the adverse effects of high temperatures on the early life stages of anadromous whitefish coregonus lavaretus were experimentally examined by assessing fertilization success, the percentage of developmental abnormalities, cumulative mortality and the rate of embryogenesis across a range of temperatures. temperatures >or= 7 degrees c increased the proportion of unfertilized and abnormally dividing eggs, deformed embryos and consequent mortality. the higher the temperature, the more severe were th ... | 2010 | 20666893 |
| both male and female sexual ornaments reflect offspring performance in a fish. | secondary sexual characters are often expressed in both sexes (mutual ornamentation), but are less often studied simultaneously. we studied the adaptive signaling function of male and female ornamentation in a mutually ornamented fish, the whitefish coregonus lavaretus. in an experimental design in which nongenetic environmental effects were minimized, we found that highly ornamented females, males, and their parental combinations had offspring with better swimming performance and predator-avoid ... | 2010 | 20629728 |
| phenotype-environment correlations in a putative whitefish adaptive radiation. | 1. the adaptive radiation of fishes into benthic (littoral) and pelagic (lentic) morphs in post-glacial lakes has become an important model system for speciation. although these systems are well studied, there is little evidence of the existence of morphs that have diverged to utilize resources in the remaining principal lake habitat, the profundal zone. 2. here, we tested phenotype-environment correlations of three whitefish (coregonus lavaretus) morphs that have radiated into littoral, pelagic ... | 2010 | 20487087 |
| intergenomic epistasis causes asynchronous hatch times in whitefish hybrids, but only when parental ecotypes differ. | support for the theory of ecological speciation requires evidence for ecological divergence between species which directly or indirectly causes reproductive isolation. this study investigates effects of ecological vs. genetic disparity of parental species on the presence of endogenous selection (deformation and mortality rates) and potential sources of exogenous selection (growth rates and hatch timing) on hybrids. hybrid embryonic development is analysed in a common-garden full-sib cross of thr ... | 2009 | 19824932 |
| pax-3 and pax-7 label muscle progenitor cells during myotomal myogenesis in coregonus lavaretus (teleostei: coregonidae). | in coregonus lavaretus, prior the mesoderm segmentation, in cells adjacent to the notochord called adaxial cells myod and slow myosin heavy chain (myhc-slow) proteins were observed. after somite formation, adaxial cells migrate towards the lateral part of the myotome and form a layer of red muscles. deeper cells differentiate into white muscle fibres. in situ hybridization using pax-3 molecular probe revealed, that after somitogenesis, pax-3 is expressed in a layer of cells superficial to the my ... | 2009 | 19793091 |
| intestinal inflammatory response of powan coregonus lavaretus (pisces) to the presence of acanthocephalan infections. | immunopathological and ultrastructural studies were carried out on the gut of 30 specimens of powan coregonus lavaretus (l.) from lake piediluco, italy. the digestive tracts of 10 (33.3%) of the powan were found to harbour an acanthocephalan dentitruncus truttae (sinzar 1955). the numerous trunk spines of d. truttae reduced the number of mucosal folds near the parasite site of infection. the acanthocephalan induced hyperplasia and hypertrophy of the intestinal mucous cells and many worms were su ... | 2009 | 19490730 |