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[enzyme serologic studies of the arctic char (salvelinus alpinus l.) of lake königssee affected by triaenophorus nodulosus]. 19863814071
infectious pancreatic necrosis virus: isolation from asymptomatic wild arctic char (salvelinus alpinus l.). 19846530721
systemic spironucleosis in sea-farmed atlantic salmon salmo salar, caused by spironucleus barkhanus transmitted from feral arctic char salvelinus alpinus?a hexamitid flagellate was found in the gall bladder and intestine of arctic char salvelinus alpinus in northern norway. scanning and transmission electron microscopy showed this flagellate to be identical to spironucleus barkhanus from grayling thymallus thymallus and farmed atlantic salmon salmo salar. it is hypothesized that systemic spironucleosis in sea-caged atlantic salmon was due to transmission of flagellates from feral char to the salmon.19989653460
the effect of dietary fatty acids on lactic acid bacteria associated with the epithelial mucosa and from faecalia of arctic charr, salvelinus alpinus (l.).arctic charr, salvelinus alpinus (l.), held in fresh water, were fed four experimental diets containing different polyunsaturated fatty acids (pufa). in addition, one group fed a diet containing only coconut oil as sole lipid source served as control. the population of aerobic heterotrophic bacteria associated with the epithelial mucosa and the faecalia was estimated using the dilution plate technique. generally, the population level of adherent bacteria increased along the digestive tract (stom ...19989830121
experimental and natural host specificity of loma salmonae (microsporidia).the microsporidian loma salmonae (putz, hoffman & dunbar, 1965) morrison & sprague, 1981 has caused significant gill disease in pacific salmon oncorhynchus spp. host specificity of the parasite was examined experimentally by per os challenge of selected salmonids and non-salmonids with infective chinook salmon o. tshawytscha gill material. pink oncorhynchus gorbuscha and chum salmon o. keta, brown salmo trutta and brook trout salvelinus fontinalis, and chinook salmon (controls) were positive, wh ...200010782347
comparative analysis of intra-individual and inter-species dna sequence variation in salmonid ribosomal dna cistrons.this study examines sequence divergence in three spacer regions of the ribosomal dna (rdna) cistron, to test the hypothesis of unequal mutation rates. portions of two transcribed spacers (its-1 and 5' ets) and the non-transcribed spacer (nts) or intergenic spacer (igs) formed the basis of comparative analyses. sequence divergence was measured both within an individual lake trout (salvelinus namaycush) and among several related salmonid species (lake trout; brook trout, salvelinus fontinalis; arc ...200010831845
molecular characterization and cytogenetic analysis of highly repeated dnas of lake trout, salvelinus namaycush.the chromosomes of lake trout (salvelinus namaycush) contain a considerable amount of heterochromatin located at the centromeres and/or telomeres of several chromosomes, including a sex-specific block located distally on the x chromosome. in order to investigate further the repetitive dnas of lake trout, genomic dna from a female was size fractionated (<600 bp) with the restriction endonuclease alui and fragments were cloned into the bacteriophage m13. a total of 42 clones were isolated. relativ ...19958565700
the effects of trh on plasma thyroid hormone levels of rainbow trout (salmo gairdneri) and arctic charr (salvelinus alpinus).plasma levels of l-thyroxine (t4) and 3,5,3'-triiodo-l-thyronine (t3) were measured in 2- to 4-year-old rainbow trout (salmo gairdneri) and arctic charr (salvelinus alpinus) intraperitoneally injected with 0.7% nacl alone (controls) or 0.7% nacl containing synthetic thyrotropin-releasing hormone (trh). blood was obtained from terminally sampled fish or from serially sampled fish cannulated in the dorsal aorta. in trout, trh (1 microgram/g body wt) significantly raised plasma t4 to maximal values ...19883149247
associations between single nucleotide polymorphisms in candidate genes and growth rate in arctic charr (salvelinus alpinus l.).we tested for associations between single nucleotide polymorphisms (snps) in five candidate genes allied with the growth hormone axis and the age-specific growth rate of arctic charr (salvelinus alpinus l.: salmonidae). two large full sib families (n=217 and 95) were created by backcrossing males that were hybrids between two phenotypically divergent populations from labrador, canada and from nauyuk lake, canada to females that were from nauyuk lake. measures of individual growth rate (wet weigh ...200312815454
nodular gill disease (amoebic gill infestation) in arctic char, salvelinus alpinus.two groups of arctic char (salvelinus alpinus) and one of rainbow trout (oncorhynchus mykiss) from a commercial fish farm in eastern canada were found to have mixed infection of the gills with flavobacterium branchiophilum (the causative agent of bacterial gill disease (bgd) and amoebae similar to those responsible for nodular gill disease (ngd). the diagnoses were confirmed by immunofluorescence antibody testing and transmission electron microscopy. the gill lesions were typical for a mixed bgd ...199910486164
putative virulence factors of atypical aeromonas salmonicida isolated from arctic charr, salvelinus alpinus (l.), and european grayling, thymallus thymallus (l.).atypical aeromonas salmonicida (aas) causes generalized lethal infections in farmed arctic charr, salvelinus alpinus (l.), and european grayling, thymallus thymallus (l.), and is thus a serious threat for culture of these fish species. virulence factors were studied among isolates of aas from arctic charr (n = 20), european grayling (n = 19) and other fish species (n = 20), of which 48 were of finnish and 11 of swedish origin. all isolates produced an a-layer. extracellular products (ecp) of the ...200312899410
[investigations in the occurrence of triaenophorus nodulosus in salvelinus alpinus in the lake of st. bartholomew]. 196414340323
baseline studies of the global pollution. i. occurrence of organohalogens in pristine european and antarctic aquatic environments.pristine alpian fresh water lakes with no run off were selected to monitor the atmospheric fall-out of c6--c12 -organochlorine compounds. off-shore marine areas were taken for monitoring the average marine pollution by these compounds. in both cases fishes have been used as bioextractors. the analytical work-up combines solvent-partition, liquid chromatography and glass capillary gas chromatography with the electron capture detector. the idenfification is done by matching high-resilution retenti ...19807399798
selective predation on parasitized prey--a comparison between two helminth species with different life-history strategies.in lake fjellfrøsvatn, northern norway, the larval helminths cyathocephalus truncatus and cystidicola farionis use gammarus lacustris as intermediate hosts and arctic charr (salvelinus alpinus) as final hosts. there was sampled 1,433 live g. lacustris from the lake and 1,964 g. lacustris from stomach contents of the charr. prevalence of infection were, respectively, 0.49% and 3.72% for c. truncatus, and 0.21% and 0.20% for c. farionis. usually, only 1 parasite was present in each host, and the 2 ...200111695412
changes in tissue cellularity are associated with growth enhancement in genetically modified arctic char (salvelinus alpinus l.) carrying recombinant growth hormone gene.biochemical and histological analyses were used to study the number and size of cells (cellularity) in tissues of fast-growing, genetically modified arctic char (salvelinus alpinus l.), overexpressing sockeye salmon (oncorhynchus nerka) growth hormone gene (ongh1). dna contents of muscle, heart, and liver were compared in transformed, sibling (age control) and 1 year older (size control) char. total white muscle cross-sectional area, white muscle fiber number, and total nuclei number within the ...200114961382
aggregation of helminths: the role of feeding behavior of fish hosts.individual arctic charr (salvelinus alpinus) from fjellfrøsvatn, northern norway, could be categorized by their stomach contents as zooplanktivores or benthivores. feeding specialization among these fish was evident from negative correlations between helminths transmitted by pelagic copepods (diphyllobothrium dendriticum and d. ditremum) and those transmitted by the benthic amphipod gammarus lacustris (cystidicola farionis and cyathocephalus truncatus). occurrences of parasite species acquired f ...200415040660
molecular genetic examination of the polymorphic arctic charr salvelinus alpinus of thingvallavatn, iceland.thingvallavatn, iceland contains two sympatric morphotypes (benthic and limnetic) of arctic charr salvelinus alpinus. each morphotype is composed of two morphs and these differ markedly in ecology, behaviour and life history. we used molecular genetic approaches to test whether (i) genetic heterogeneity exists among morphs and (ii) if morphs arose in allopatry and came into secondary contact or arose sympatrically within the lake through genetic segregation and/or phenotypic plasticity. direct s ...19968981767
a repetitive element in the genome of atlantic salmon, salmo salar.when atlantic salmon (salmo salar) genomic dna is digested with the restriction endonuclease bgli and the fragments separated by agarose-gel electrophoresis, bands corresponding to approximately 430 and 923 bp are visualized after etdbr staining. the 923-bp band was excised from a preparative gel and used to screen a salmon genomic library for recombinant phage (re-phage) containing the repeat. the bgli repeat element is tandemly arrayed, and an array from one re-phage has been sequenced. the bg ...19938406016
kinetics of t4 and t3 binding to plasma sites in salmonid teleost fish.the relative affinities and maximum capacities of the classes of l-thyroxine (t4)- and 3,5,3'-triiodo-l-thyronine (t3)-binding sites in plasma of three species of salmonid teleost fish were determined by saturation analysis on miniature sephadex g-25 columns at 20-21 degrees and kinetic data were analyzed by the multiligand, multisite ligand computer program. in plasma of rainbow trout (salmo gairdneri) homologous ligand displacement indicated that both thyroid hormones (th) bound to a minimum o ...19873817450
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, ...200312733793
comparative genome analysis of the primary sex-determining locus in salmonid fishes.we compared the y-chromosome linkage maps for four salmonid species (arctic charr, salvelinus alpinus; atlantic salmon, salmo salar; brown trout, salmo trutta; and rainbow trout, oncorhynchus mykiss) and a putative y-linked marker from lake trout (salvelinus namaycush). these species represent the three major genera within the subfamily salmoninae of the salmonidae. the data clearly demonstrate that different y-chromosomes have evolved in each of the species. arrangements of markers proximal to ...200312566405
increased susceptibility of salmonids to the monogenean gyrodactylus salaris following administration of hydrocortisone acetate.gyrodactylus salaris infects numerous salmonid species, ranging from the fully susceptible (norwegian strains of salmo salar), through species which, though initially susceptible, eventually eliminate their infections (salvelinus alpinus and s. fontinalis) to entirely resistant (salmo trutta) species. here we describe experiments in which salvelinus alpinus, s. fontinalis and salmo trutta, implanted with hydrocortisone acetate to simulate stress-induced immunosuppression, were challenged with g. ...200010726266
transfer of growth hormone (gh) transgenes into arctic charr. (salvelinus alpinus l.) ii. nutrient partitioning in rapidly growing fish.to examine whether the utilization of protein and lipids is altered in the genetically modified, rapidly growing charr, we compared cmvongh1 transgenic and sibling fish. muscle composition and rates of gas exchange were analyzed. plasma metabolites were determined in the recently fed and post-absorptive state. no difference was found in muscle composition. at equal rates of protein accretion, the rate of nh4 excretion was 43% greater in sibling charr. the lower molar ratio of nh4 to o2 exchange ...199910596747
transfer of growth hormone (gh) transgenes into arctic charr. (salvelinus alpinus l.) i. growth response to various gh constructs.four constructs containing salmonid growth hormone (gh) genes were transferred to arctic charr (salvelinus alpinus l.). cytomegalovirus (cmv) and piscine metallothionein b (onmt) and histone 3 (onh3) promoters connected to sockeye salmon growth hormone 1 gene (ongh1) were used for ectopic expression, and atlantic salmon growth hormone 2 gene with 5'flanking region (ssgh2) was tested for pituitary-specific expression. charr carrying the ongh1 constructs showed a dramatic increase in growth rate. ...199910596746
the effect of diet on aerobic bacterial flora associated with intestine of arctic charr (salvelinus alpinus l.).in order to extend the knowledge on the possible effect of diet on the gastrointestinal microbial community of fish, arctic charr (salvelinus alpinus l.) were fed diets containing high (23.7%) and low (6.4%) levels of carbohydrate. the number of viable aerobic and facultative aerobic bacteria associated with the digestive tract were not influenced by dietary regimen. a wide range of bacterial species was isolated, and the predominant bacterial species of both rearing groups were identified as st ...199910030010
spatial and temporal trends of mercury and other metals in landlocked char from lakes in the canadian arctic archipelago.spatial and temporal trends of mercury (hg) and 22 other elements were examined in landlocked arctic char (salvelinus alpinus) from six lakes in the canadian arctic (char, resolute and north lakes, and amituk lake on cornwallis island, sapphire lake on devon island and boomerang lake on somerset island). the objectives of the study were to compare recent concentrations of hg and other metals in char with older data from amituk, resolute and char lakes, in order to examine temporal trends as well ...200516165187
similar localization of immunoreactive glutamate and aspartate in the pineal organ and retina of various nonmammalian vertebrates.the localization of immunoreactive glutamate and aspartate was compared in the pineal organ and retina of various vertebrates (raja clavata, carassius auratus, salvelinus alpinus, triturus vulgaris, triturus cristatus, lacerta muralis, lacerta agilis, lacerta viridis, columbia livia and white leghorn chicken) by postembedding immunoelectron microscopy. immunoreaction of both excitatory amino acids was detected in the pinealocytes in a localization similar to that of retinal photoreceptors. the r ...19958714767
trophic transfer of persistent organochlorine contaminants (ocs) within an arctic marine food web from the southern beaufort-chukchi seas.stable isotope values (13c, 15n) and concentrations of persistent organochlorine contaminants (ocs) were determined to evaluate the near-shore marine trophic status of biota and biomagnification of ocs from the southern beaufort-chukchi seas (1999-2000) near barrow, ak. the biota examined included zooplankton (calanus spp.), fish species such as arctic cod (boreogadus saida), arctic char (salvelinus alpinus), pink salmon (oncorhynchus gorbuscha), and fourhorn sculpin (myoxocephalus quadricornis) ...200312758030
are secondary sex traits, parasites and immunity related to variation in primary sex traits in the arctic charr?primary and secondary sex traits are influenced by the same sex hormones, and the expression of secondary sex traits may consequently signal males' capacity for sperm production. sperm quality may also be influenced by immune activity, as sperm are non-self to the male. parasite infections alter immune activity and may thus reduce ejaculate quality. in the arctic charr (salvelinus alpinus) the red abdominal colour is considered an ornament that signals important information in mate choice. we ca ...200415101414
sacciform cells in the epidermis of the brown trout, salmo trutta, and the arctic char, salvelinus alpinus.sacciform cells containing an acidophilic, proteinaceous secretion, were identified in the epidermis of the brown trout and arctic char. this cell type increased in number during the chronic stages of infestation by the ectoparasitic flagellate, ichthyobodo sp., in immature brown trout, and decreased during sexual maturation in male brown trout and char. it is suggested that the salmonid sacciform cell produces a secretion which protects the fish against infestation or damage by skin parasites.19873815480
effects of catecholamines on plasma thyroid hormone levels in arctic charr, salvelinus alpinus.plasma levels of l-thyroxine (t4) and 3,5,3'-triiodo-l-thyronine (t3) were measured in arctic charr at 2, 6, or 24 hr after single intraperitoneal injection of epinephrine (e) or norepinephrine (ne). at a dose of approximately 1 microgram/g body wt (sufficient to cause a submaximal dermal melanophore pallor response) plasma t4 was usually elevated at 2 hr, consistently depressed at 6 hr, and unaffected at 24 hr. there was no effect of e on plasma [125i]t4 kinetics or [125i]t4 5'-monodeiodination ...19863557064
short-term treatment with testosterone increases plasma 3,5,3'-triiodo-l-thyronine and hepatic l-thyroxine 5'-monodeiodinase levels in arctic charr, salvelinus alpinus.testosterone (t), methyl testosterone (mt), and testosterone propionate (tp) (0.5 mg/100 g body wt in 40 microliter peanut oil) or peanut oil alone were injected (ip) on days 0 and 3 into immature arctic charr (salvelinus alpinus). charr were sampled on days 7 and 12 and plasma testosterone, l-thyroxine (t4), 3,5,3'-triiodo-l-thyronine (t3), and hepatic microsomal t4 5'-monodeiodinase (t4 5'd) measured. plasma androgen levels were elevated by all androgen treatments to levels similar to those ob ...19883410289
host specificity and geographical distribution of eubothrium in european salmonid fish.the host specificity and distribution of eubothrium crassum (bloch, 1779) and eubothrium salvelini (schrank, 1790), morphologically fairly similar pseudophyllidean tapeworms parasitizing salmonid fish, were critically assessed on the basis of morphological and genetic evaluation of extensive material collected from different definitive hosts and geographical regions in europe. eubothrium crassum occurs in fish of the genera salmo, i.e. salmon (s. salar - both freshwater and marine), sea trout (s ...200312895285
comparison of myosin isoenzymes present in skeletal and cardiac muscles of the arctic charr salvelinus alpinus (l.). sequential expression of different myosin heavy chains during development of the fast white skeletal muscle.the expression of myosin isoforms and their subunit composition in the white skeletal body musculature of arctic charr (salvelinus alpinus) of different ages (from 77-day embryos until about 5 years old) was studied at the protein level by means of electrophoretic techniques. myosin from the white muscle displayed three types of light chain during all the developmental stages examined: two myosin light chains type 1 (lc1f) differing in both apparent molecular mass and pi, one myosin light chain ...19911825632
levels and spatial and temporal trends of contaminants in greenland biota: an updated review.knowledge of contaminant levels in greenland biota has increased substantially in recent years, particularly for persistent organic pollutants. this paper reviews and updates knowledge of spatial and temporal trends of cd, hg and organochlorines (pcbs, ddts, hchs, hcb and chlordane-related compounds) in greenland terrestrial, freshwater and marine biota. the most comprehensive studies of spatial trends of cd and hg in the terrestrial ecosystem concern lichens, with relatively complete coverage, ...200415325140
rapid evolution of muscle fibre number in post-glacial populations of arctic charr salvelinus alpinus.thingvallavatn, the largest and one of the oldest lakes in iceland, contains four morphs of arctic charr salvelinus alpinus. dwarf benthic (db), large benthic (lb), planktivorous (pl) and piscivorous (pi) morphs can be distinguished and differ markedly in head morphology, colouration and maximum fork length (fl(max)), reflecting their different resource specialisations within the lake. the four morphs in thingvallavatn are thought to have been isolated for approximately 10 000 years, since short ...200415557021
comparison of antimicrobial activity in the epidermal mucus extracts of fish.the mucus layer on the surface of fish consists of several antimicrobial agents that provide a first line of defense against invading pathogens. to date, little is known about the antimicrobial properties of the mucus of arctic char (salvelinus alpinus), brook trout (s. fontinalis), koi carp (cyprinus carpio sub sp. koi), striped bass (morone saxatilis), haddock (melanogrammus aeglefinus) and hagfish (myxine glutinosa). the epidermal mucus samples from these fish were extracted with acidic, orga ...200818342561
elevated spring temperature stimulates growth, but not smolt development, in anadromous arctic charr.parr-smolt transformation and growth were studied in captive offspring of anadromous arctic charr (salvelinus alpinus) from the hals watercourse in northern norway (70 degrees n), held either at a natural temperature (<1 degrees c until may) or at a temperature elevated to 6 degrees c in late march. in mid-may, 5 weeks after the increase in photoperiod from 8:16 h light:dark to continuous light, gill na+, k(+)-atpase activity started to increase in both temperature groups, concurrent with the fi ...200818700168
temperature effect on the immune defense functions of arctic charr salvelinus alpinus.the arctic charr salvelinus alpinus is an endangered fish species in finland, and thus farming is carried out mainly for stocking purposes. farmed charr are susceptible to infection with atypical aeromonas salmonicida (aas). losses of valuable brood stock will severely reduce the genetic diversity of stocked charr. no commercial vaccines are available to prevent aas infection, and vaccines against furunculosis (caused by typical a. salmonicida, tas) do not protect the charr against aas infection ...200212517005
analysis of two igm isotypes in atlantic salmon and brown trout.atlantic salmon (salmo salar) possesses two distinct subpopulations of polymeric igm which are separable by anion exchange chromatography. consistent with this finding there are two isotypic igm heavy chain genes, cmua and cmub, in the genome of this species, presumably as a result of ancestral tetraploidy. in the present study it was shown that igm of brown trout (salmo trutta) is also separated into two subpopulations by anion exchange chromatography, while igm of rainbow trout (oncorhynchus m ...200212220889
characterization of carnobacterium divergens strain 6251 isolated from intestine of arctic charr (salvelinus alpinus l.).an atypical strain of carnobacterium divergens, strain 6251, was isolated from the small intestine of arctic charr (salvelinus alpinus l.), fed high dietary carbohydrate. this strain showed marked growth inhibitory effects in vitro against the fish pathogens aeromonas salmonicida subsp. salmonicida (furunculosis), vibrio anguillarum (vibriosis) and vibrio viscocus (winter ulcer). the strain is a non-motile gram-positive psychrotrophic rod that lacks both catalase and oxidase, grows at ph 9.1 (ct ...200212086178
bis(4-chlorophenyl) sulfone (bcps) in swedish marine and fresh water wildlife-a screening study.bis(4-chlorophenyl) sulfone (bcps) is a high production volume chemical (hpvc) applied in thermostable polymers. bcps has been detected as an environmental contaminant both in europe and in north america but it is still not a commonly studied pollutant. in this study, three baltic sea fish species; herring (clupea harengus), salmon (salmo salar) and perch (perca fluviatilis) from the swedish coast, and one inland fish species, arctic char (salvelinus alpinus), were analysed to screen for the occ ...200415051243
identification and characterization of carnobacteria isolated from fish intestine.eleven bacterial strains were isolated from the gastrointestinal tract of four fish species, atlantic salmon (salmo salar l.), arctic charr (salvelinus alpinus l.), atlantic cod (gadus morhua l.) and wolffish (anarhichas lupus l.). all the strains were gram-positive rods, non-sporing, catalase and oxidase-negative, able to grow at ph 9.0 but not on acetate containing media (ph < or = 5.4), and were fermentative. they had a high content of oleic acid (18:1 n-9) in cellular lipid, and were found t ...200111518321
vaccination influences growth of arctic charr.there is limited knowledge about the effects of oil-based vaccines on the growth of arctic charr salvelinus alpinus, in particular at different rearing temperatures. one-year-old arctic charr were immunized intraperitoneally at 2.9 degrees c with a metabolizable oil-adjuvanted, bivalent vaccine containing killed typical and atypical aeromonas salmonicida bacteria. after vaccination the non-vaccinated (controls) and vaccinated individually marked fish were held for 20 d at 10.0 degrees c and then ...200011129384
ssu rrna gene sequence reveals two genotypes of spironucleus barkhanus (diplomonadida) from farmed and wild arctic charr salvelinus alpinus.spironucleus barkhanus isolated from the blood of arctic charr salvelinus alpinus from a marine fish farm were genetically compared with s. barkhanus isolated from the gall bladder of wild arctic charr. the wild arctic charr were caught in the lake used as the water source for the hatchery from which the farmed fish originated. sequencing of the small subunit ribosomal rna gene (ssu rdna) from these 2 populations showed that the isolates obtained from farmed and wild arctic charr were only 92.7 ...200415648835
aroclor 1254 exposure reduces disease resistance and innate immune responses in fasted arctic charr.to examine the immunological impacts of polychlorinated biphenyls (pcbs) in an environmentally relevant way, we orally contaminated arctic charr (salvelinus alpinus) with aroclor 1254. after contamination, fish were either fed (0 and 100 mg aroclor 1254 kg(-1) fish wt) or fasted (0, 1, 10, and 100 mg kg(-1)) to mimic cycles of feeding-fasting experienced by arctic animals. after four months, pcb concentrations in muscle were the same in fasted and fed fish; however, pcbs in kidneys of fed fish w ...200515683174
growth, nutritional composition, and hematology of arctic charr (salvelinus alpinus) exposed to toxaphene and tapeworm (diphyllobothrium dendriticum) larvae.toxaphene, an organochlorine pesticide, is the major contaminant of arctic charr (salvelinus alpinus) in the canadian arctic. the objective of this study was to investigate the combined effects of toxaphene exposure and infection by the larval stage of the cestode diphyllobothrium dendriticum on fish growth, nutritional composition, and hematology. hatchery-reared arctic charr were subjected to one of four treatments: (1) oral administration of corn oil (control); (2) single oral dose of 10 micr ...200515719195
enantiomer-specific biomagnification of alpha-hexachlorocyclohexane and selected chiral chlordane-related compounds within an arctic marine food web.concentrations of achiral and chiral organochlorine contaminants (ocs), including hexachlorocyclohexane isomers (hch), chlordane congeners (cis- and trans-chlordane, cis- and trans-nonachlor, mc5, mc7, and u82), and related metabolites (oxychlordane [oxy] and heptachlor exo-epoxide [hepx]), were quantified in seawater (100 l; n = 6) and biota from the coastal beaufort-chukchi seas food web near barrow (ak, usa). the biota included zooplankton (calanus spp.; n = 5), fish species such as arctic co ...200314552014
characterisation of atypical aeromonas salmonicida infection in arctic charr salvelinus alpinus and european grayling thymallus thymallus.cultured stocks of arctic charr salvelinus alpinus and european grayling thymallus thymallus are vulnerable to infection by achromogenic atypical aeromonas salmonicida (aas). in finland, natural stocks of both fish species have to be supported by restocking, and aas infection poses a threat to successful restocking because no preventive means are available. in this study, we analysed aas isolates from arctic charr and european grayling and from other sources genetically, and characterised the si ...200516231637
toxicity of acid aluminium-rich water to seven freshwater fish species: a comparative laboratory study.the present study focuses on the relative sensitivity among freshwater fish species to aqueous aluminium. seven common scandinavian fish species were exposed to acidic al-rich water, acidic al-poor water, and approximately neutral water as a control. the relative sensitivity among the species to an acute aluminium challenge was documented, and was in the following order: atlantic salmon, salmo salar, as the most sensitive; then roach, rutilus rutilus; minnow, phoxinus phoxinus; perch, perca fluv ...199715093412
the effect of dietary supplementation with blueberry, alpha-tocopherol or astaxanthin on oxidative stability of arctic char (salvelinus alpinus) semen.the objective was to determine the oxidative stability of arctic char (salvelinus alpinus) semen following dietary supplementation with lowbush blueberry (vaccinium angustifolium) product, alpha-tocopherol, alpha-tocopherol+blueberry product, or alpha-tocopherol+astaxanthin. sperm lipid peroxidation was initiated by challenging with ferrous sulphate/ascorbic acid (fe(++)/asc) at level of 0.04/0.2 mmol/l. addition of blueberry, alpha-tocopherol, or both to char diets inhibited semen lipid peroxid ...200616420960
a linkage map for brown trout (salmo trutta): chromosome homeologies and comparative genome organization with other salmonid fish.we report on the construction of a linkage map for brown trout (salmo trutta) and its comparison with those of other tetraploid-derivative fish in the family salmonidae, including atlantic salmon (salmo salar), rainbow trout (oncorhynchus mykiss), and arctic char (salvelinus alpinus). overall, we identified 37 linkage groups (2n = 80) from the analysis of 288 microsatellite polymorphisms, 13 allozyme markers, and phenotypic sex in four backcross families. additionally, we used gene-centromere an ...200616452148
occurrence of the microsporidian parasite nucleospora salmonis in four species of salmonids from the massif central of france.nucleospora salmonis (hedrick, groff et baxa, 1991), an intranuclear microsporidian parasite of marine and freshwater fish, causes diseases mainly in salmonid species. losses have been reported in stocks of salmonid fish reared in the region of auvergne (france). the cause of chronic mortalities in the local host species raised in aquaculture and destined for supplementation of the river system loire-allier was examined. the presence of n. salmonis was confirmed by pcr and histology in salmo sal ...200616696429
intracellular infection with spironucleus barkhanus (diplomonadida: hexamitidae) in farmed arctic char salvelinus alpinus.a case of intracellular systemic infection with the diplomonad flagellate spironucleus barkhanus in farmed arctic char salvelinus alpinus is described. the parasites were widely disseminated throughout the vasculature and in most organs. aggregates of the parasites were seen within well-defined structures regarded as host cells in capillaries and sinusoids of the liver, spleen and head kidney. intracellular infection with spironucleus spp. has never previously been reported. the prevalence of in ...200314598991
a new akirin1 gene in turbot (scophthalmus maximus): molecular cloning, characterization and expression analysis in response to bacterial and viral immunological challenge.smakirin1, a member of the nf-?b signaling pathway, was isolated from turbot by race. its cdna was 564 bp and encoded a putative protein of 187 amino acids with a predicted molecular mass of 21 kda and an isoelectric point (pi) of 9.05. amino acid sequence alignments showed that smakirin1 was 91% identical to the salvelinus alpinus akirin1 protein acv49694. transient expression of smakirin1-gfp in the turbot kidney cell line smkc revealed a nuclear localization of the protein, and a typical nls ...201121300161
development of a multichemical food web model: application to pbdes in lake ellasjoen, bear island, norway.a multichemical food web model has been developed to estimate the biomagnification of interconverting chemicals in aquatic food webs. we extended a fugacity-based food web model for single chemicals to account for reversible and irreversible biotransformation among a parent chemical and transformation products, by simultaneously solving mass balance equations of the chemicals using a matrix solution. the model can be applied to any number of chemicals and organisms or taxonomic groups in a food ...200616913129
relationships between plasmids and phenotypes of presumptive strains of vibrio anguillarum isolated from different fish species.on the basis of plasmid composition as well as serological and biochemical properties, 26 strains identified as vibrio anguillarum isolated from diseased fish could be assigned to two different groups. except for three reference strains, these++ strains were isolated from norwegian fish. the four strains isolated from rainbow trout (salmo gairdneri), the only strain isolated from char (salvelinus alpinus), and three of six strains isolated from atlantic salmon (salmo salar) harbored a plasmid of ...19892729984
characterization of a neochlamydia-like bacterium associated with epitheliocystis in cultured arctic charr salvelinus alpinus.infections of branchial epithelium by intracellular gram-negative bacteria, termed epitheliocystis, have limited culture of arctic charr salvelinus alpinus. to characterize a bacterium associated with epitheliocystis in cultured charr, gills were sampled for histopathologic examination, conventional and immunoelectron microscopy, in situ hybridization, 16s ribosomal dna (rdna) amplification, sequence analysis and phylogenetic inference. sampling was conducted at the freshwater institute (shepher ...200717718162
[peculiarities of the parasitofauna of atlantic salmon parr (salmo salar l.), brown trout (salmo truttae l.), and char (salvelinus alpinus l.) in the utsjoki river system (northern finland)].data on the parasite diversity in salmonidae fish parr from different parts of the utsjoki river obtained during 1993-1995 and 2006-2007 are presented. three fish species, salmo salar l., s. truttae l., and salvelinus alpinus l., were examined on the presence of helminthes. twenty species of salmon parasites were found, the majority of which are the parasites with complicated life cycles. infusorians c apriniana piscium, myxosporidia chloromyxum januaricus and myxobolus neurobius, metacercaria o ...201121598666
metamorphosis in chironomids, more than mercury supply, controls methylmercury transfer to fish in high arctic lakes.lake-dwelling arctic char (salvelinus alpinus) are monitored internationally as a sentinel species for effects of atmospheric mercury deposition on arctic fresh waters. we investigated the control of mercury supply and biological processes on the methylmercury (mehg) content of their main food, aquatic chironomids, in 22 lakes and ponds in the canadian high arctic. total mercury (thg) concentrations in sediment (corrected for organic matter content) increased with drainage basin size, suggesting ...200819174879
outbreaks of an ulcerative and haemorrhagic disease in arctic char salvelinus alpinus caused by aeromonas salmonicida subsp. smithia.arctic char salvelinus alpinus farmed in different places in austria and free of the viral diseases viral haemorrhagic septcaemia (vhs), infectious haematopoietic necrosis (ihn) and infectious pancreatic necrosis (ipn) experienced disease and mortality. diseased fish showed skin ulceration and pathological signs of sepsis. aeromonas sp. was isolated as pure culture from the kidney of freshly euthanized diseased fish. three independent isolates from outbreaks that occurred on 2 of the affected fa ...200919899353
bulbodacnitis alpinus sp. nov. (nematoda: cucullanidae) from arctic char, salvelinus alpinus l., with notes on other species of bulbodacnitis. 20154832960
linkage relationships reflecting ancestral tetraploidy in salmonid fish.fifteen classical linkage groups were identified in two salmonid species (salmo trutta and salmo gairdneri) and three fertile, interspecific hybrids (s. gairdneri x salmo clarki, salvelinus fontinalis x salvelinus namaycush and s. fontinalis x salvelinus alpinus) by backcrossing multiply heterozygous individuals. these linkage relationships of electrophoretically detected, protein coding loci were highly conserved among species. the loci encoding the enzymes appeared to be randomly distributed a ...20133623080
exposure and effects assessment of persistent organohalogen contaminants in arctic wildlife and fish.persistent organic pollutants (pops) encompass an array of anthropogenic organic and elemental substances and their degradation and metabolic byproducts that have been found in the tissues of exposed animals, especially pops categorized as organohalogen contaminants (ohcs). ohcs have been of concern in the circumpolar arctic for decades. for example, as a consequence of bioaccumulation and in some cases biomagnification of legacy (e.g., chlorinated pcbs, ddts and chls) and emerging (e.g., bromin ...201019910021
the placement of gyrodactylus salmonis (yin & sproston) in the molecular phylogeny of studied members of the gyrodactylus wageneri-group parasitizing salmonids.the molecular phylogeny of gyrodactylus salmonis from brook charr, salvelinus fontinalis, rainbow trout, oncorhynchus mykiss, cutthroat trout, o. clarkii, and atlantic salmon, salmo salar, in canada is presented using sequences from its-rdna and the mitochondrial cox 1 gene. sequence variation among g. salmonis specimens from the different north american hosts was consistent with within-species variation reported for other gyrodactylus. sequence data are compared to those from other members of t ...201020367738
identification of 'candidatus piscichlamydia salmonis' in arctic charr salvelinus alpinus during a survey of charr production facilities in north america.arctic charr salvelinus alpinus production facilities, nonproduction water sources and effluents in the united states and canada were sampled to determine if chlamydiae associated with epitheliocystis were present in water and were associated with inclusions of epitheliocystis in gill tissue. gills from 607 fish from 13 sites were processed for histopathologic examination and dna extraction. water was collected from 21 locations for dna testing. eighteen fish from one location had inclusions of ...201020391911
morphological variation over ontogeny and environments in resource polymorphic arctic charr (salvelinus alpinus).natural selection requires genetically based phenotypic variation to facilitate its action and cause adaptive evolution. it has become increasingly recognized that morphological development can become canalized likely as a result of selection. however, it is largely unknown how selection may influence canalization over ontogeny and differing environments. changes in environments or colonization of a novel one is expected to result in adaptive divergence from the ancestral population when selecti ...201020565535
a multivariate comparison of the stress response in three salmonid and three cyprinid species: evidence for inter-family differences.the response of six species of freshwater fishes, from the families cyprinidae (common carp cyprinus carpio, roach rutilus rutilus and chub leuciscus cephalus) and salmonidae (rainbow trout oncorhynchus mykiss, brown trout salmo trutta and arctic charr salvelinus alpinus), to a standardized stressor was evaluated. a 6 h period of confinement resulted in changes to plasma cortisol, glucose, amino acid and lactate levels compared with unconfined controls. there were significant differences in the ...201020666900
polybromodiphenyl ether flame retardants in fish from lakes in european high mountains and greenland.individual polybromodiphenyl ethers (pbdes) were investigated in liver and muscle tissue of trout from 11 high mountain lakes in europe and one in greenland. trouts in these lakes [brown trout (salmo trutta), brook trout (salvelinus fontinalis) and arctic char (salvelinus alpinus)] are important sentinel species because they are located in the top of the food chain and pollution can only reach these ecosystems by atmospheric transport. the major pbde congeners were bde 47 and bde 99, followed by ...200415116838
incipient speciation through niche expansion: an example from the arctic charr in a subarctic lake.two reproductive isolated morphs of arctic charr (salvelinus alpinus), termed profundal and littoral charr according to their different spawning habitats, co-occur in the postglacial lake fjellfrøsvatn in north norway. all profundal charr live in deep water their entire life and have a maximum size of 14cm, while the littoral charr grow to 40cm. some small and young littoral charr move to the profundal zone in an ontogenetic habitat shift in the ice-free season and the rest of the population rem ...200616928630
characterisation and expression of the paired box protein 7 (pax7) gene in polymorphic arctic charr (salvelinus alpinus).arctic charr (salvelinus alpinus l.) from lake thingvallavatn, iceland occur as four distinct morphs: large benthivorous (lb), dwarf benthivorous (db), piscivorous (pi) and planktonivorous (pl). the morphs differ with respect to body size, head morphology, growth rate, and life history. the aim of this study was to investigate the paired box protein 7 (pax7) gene as a candidate for such polymorphisms due to its importance in cranio-facial, skeletal muscle, and central nervous system development. ...200617049897
arctic charr (salvelinus alpinus) is a suitable host for gyrodactylus salaris (monogenea, gyrodactylidae) in norway.gyrodactylus specimens infecting both anadromous arctic charr (salvelinus alpinus) from river signaldalselva (northern norway) and resident arctic charr from lake pålsbufjorden (southern norway) were identified as g. salaris using molecular markers and morphometrics. the infection in pålsbufjorden represents the first record of a viable g. salaris population infecting a host in the wild in the absence of salmon (salmo salar). g. salaris on charr from signaldalselva and pålsbufjorden bear differe ...200717054822
direct and indirect climatic drivers of biotic interactions: ice-cover and carbon runoff shaping arctic char salvelinus alpinus and brown trout salmo trutta competitive asymmetries.one of the major challenges in ecological climate change impact science is to untangle the climatic effects on biological interactions and indirect cascading effects through different ecosystems. here, we test for direct and indirect climatic drivers on competitive impact of arctic char (salvelinus alpinus l.) on brown trout (salmo trutta l.) along a climate gradient in central scandinavia, spanning from coastal to high-alpine environments. as a measure of competitive impact, trout food consumpt ...201121805086
wild arctic char salvelinus alpinus and trout salmo trutta: hosts and reservoir of the salmonid pathogen spironucleus salmonicida (diplomonadida; hexamitidae).spironucleus salmonicida is a diplomonad flagellate known to cause systemic infections in farmed salmonids. in northern norway, outbreaks of spironucleosis in farmed atlantic salmon salmo salar have been a recurring problem. common to all these outbreaks was the origin of smolts: all came from the same farm. in the present study, wild arctic char salvelinus alpinus and brown trout salmo trutta were sampled from the lakes used as a water source for the smolt supplier. in addition, smolt and three ...201122235595
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 ...201526213992
density-dependent diel activity in stream-dwelling arctic charr salvelinus alpinus.intraspecific competition plays a significant role in shaping how animals use and share habitats in space and time. however, the way individuals may modify their diel activity in response to increased competition has received limited attention. we used juvenile (age 1+) arctic charr salvelinus alpinus to test the prediction that individuals at high population density are more active and distribute their foraging activity over a greater portion of the 24-h cycle than individuals at low population ...201627247761
mercury concentrations in arctic food fishes reflect the presence of anadromous arctic charr (salvelinus alpinus), species, and life history.single-spawning (semelparous) anadromous fishes are known to transport contaminants from marine to freshwater habitats, but little research has been conducted on contaminant biotransport by multiple-spawning (iteroparous) anadromous fishes. we examined the effect of iteroparous, anadromous arctic charr (salvelinus alpinus) on mercury concentrations ([hg]) in freshwater biota and compared [hg] between species and life history types of arctic charr and lake trout (salvelinus namaycush). data from ...201020384334
implications of climate change for the fishes of the british isles.recent climatic change has been recorded across the globe. although environmental change is a characteristic feature of life on earth and has played a major role in the evolution and global distribution of biodiversity, predicted future rates of climatic change, especially in temperature, are such that they will exceed any that has occurred over recent geological time. climate change is considered as a key threat to biodiversity and to the structure and function of ecosystems that may already be ...200920735625
experiments to test if allopatric salvelinus alpinus are suitable year-round hosts of gyrodactylus salaris (monogenea).there has been an increased focus on salvelinus alpinus as a potential long-term host to gyrodactylus salaris and, here, both susceptibility to g. salaris and ability to sustain a parasite population seasonally, was tested using fry and parr of s. alpinus from the river skibotnelva, northern norway. fry were highly susceptible. gyrodactylus salaris survived on allopatric s. alpinus parr during the 5 month-long winter when water temperatures were c. 1 degrees c. salvelinus alpinus fry also mainta ...200920735647
mercury concentrations in landlocked arctic char (salvelinus alpinus) from the canadian arctic. part i: insights from trophic relationships in 18 lakes.concentrations of mercury (hg) have increased slowly in landlocked arctic char over a 10- to 15-year period in the arctic. fluxes of hg to sediments also show increases in most arctic lakes. correlation of hg with trophic level (tl) was used to investigate and compare biomagnification of hg in food webs from lakes in the canadian arctic sampled from 2002 to 2007. concentrations of hg (total hg and methylmercury [mehg]) in food webs were compared across longitudinal and latitudinal gradients in r ...201020821487
mercury concentrations in landlocked arctic char (salvelinus alpinus) from the canadian arctic. part ii: influence of lake biotic and abiotic characteristics on geographic trends in 27 populations.among-lake variation in mercury (hg) concentrations in landlocked arctic char was examined in 27 char populations from remote lakes across the canadian arctic. a total of 520 landlocked arctic char were collected from 27 lakes, as well as sediments and surface water from a subset of lakes in 1999, 2002, and 2005 to 2007. size, length, age, and trophic position (delta(15)n) of individual char were determined and relationships with total hg (thg) concentrations investigated, to identify a common c ...201020821488
the utilization of a pacific salmon oncorhynchus nerka subsidy by three populations of charr salvelinus spp.the l(f) -at-age trajectories differentiated two populations of dolly varden charr salvelinus malma and a population of arctic charr salvelinus alpinus from the eastern end of iliamna lake, alaska. salvelinus malma from the pedro bay ponds were the smallest for a given age, followed by salvelinus alpinus from the lake, and s. malma from the iliamna river were much larger. the utilization of a large sockeye salmon oncorhynchus nerka subsidy by the three salvelinus spp. populations was then invest ...201020840627
temperature requirements of atlantic salmon salmo salar, brown trout salmo trutta and arctic charr salvelinus alpinus: predicting the effects of climate change.atlantic salmon salmo salar, brown trout salmo trutta (including the anadromous form, sea trout) and arctic charr salvelinus alpinus (including anadromous fish) provide important commercial and sports fisheries in western europe. as water temperature increases as a result of climate change, quantitative information on the thermal requirements of these three species is essential so that potential problems can be anticipated by those responsible for the conservation and sustainable management of t ...201021078091
ice-cover effects on competitive interactions between two fish species.1. variations in the strength of ecological interactions between seasons have received little attention, despite an increased focus on climate alterations on ecosystems. particularly, the winter situation is often neglected when studying competitive interactions. in northern temperate freshwaters, winter implies low temperatures and reduced food availability, but also strong reduction in ambient light because of ice and snow cover. here, we study how brown trout [salmo trutta (l.)] respond to va ...201021198589
reproduction impairment following paternal genotoxin exposure in brown trout (salmo trutta) and arctic charr (salvelinus alpinus).this work describes some consequences of paternal germ cell dna damage on the reproduction success in two fish species. male brown trout (n=31) and male arctic charr (n=28) were exposed to the model genotoxicant mms at the end of spermatogenesis to generate a significant dna damage level in mature spermatozoa (28% and 25% tail dna in trout and charr sperm, respectively, evaluated through the comet assay). sperm from each mms exposed and control fish was then used to fertilize in vitro an aliquot ...201021216351
comparison of mercury concentrations in landlocked, resident, and sea-run fish (salvelinus spp.) from nunavut, canada.mercury concentrations ([hg]) in arctic food fish often exceed guidelines for human subsistence consumption. previous research on two food fish species, arctic char (salvelinus alpinus) and lake trout (salvelinus namaycush), indicates that anadromous fish have lower [hg] than nonanadromous fish, but there have been no intraregional comparisons. also, no comparisons of [hg] among anadromous (sea-run), resident (marine access but do not migrate), and landlocked (no marine access) life history type ...201121381088
real-time pcr detection of parvicapsula pseudobranchicola (myxozoa: myxosporea) in wild salmonids in norway.the myxozoan genus parvicapsula contains 14 species infecting fish, some of which are known to cause severe disease in farmed and wild salmonids. parvicapsula pseudobranchicola infections were first reported from seawater-reared atlantic salmon, salmo salar, in norway in 2002 and have since then been an increasing problem. the present study describes a taqman real-time pcr assay for specific detection of p. pseudobranchicola. the taqman assay targets the 18s rrna gene of p. pseudobranchicola and ...201121401644
same barcode, different biology: differential patterns of infectivity, specificity and pathogenicity in two almost identical parasite strains.two norwegian isolates of the monogenean gyrodactylus salaris malmberg, 1957 with identical cytochrome c oxidase subunit i barcodes from different hosts, show highly divergent biological and behavioural characteristics. the lierelva parasite strain, typically infecting atlantic salmon, salmo salar l., grew exponentially on atlantic salmon, but the pålsbufjorden parasite strain, commonly infecting arctic charr, salvelinus alpinus l., grew slowly on both hosts and was non-pathogenic to atlantic sa ...201424874264
freshwater charr (salvelinus alpinus) as hosts for gyrodactylus salaris: implications for management. 201121493514
variation in host preference within gyrodactylus salaris (monogenea): an experimental approach.the monogenean ectoparasite, gyrodactylus salaris malmberg, 1957, has had a devastating effect on wild atlantic salmon (salmo salar) since its introduction to norway in the mid-1970s. in lake pålsbufjorden, southern norway, upstream of the stretches of the river numedalslågen with anadromous atlantic salmon, a resident arctic charr (salvelinus alpinus) population has been reported to be infected with g. salaris which is viable in the absence of its normal host, the atlantic salmon. currently, th ...200717166321
experimental challenges with renibacterium salmoninarum in arctic charr salvelinus alpinus.arctic charr salvelinus alpinus l. is an important species in icelandic aquaculture and the most common wild salmonid in iceland. a study on the course of infection with the bacterium renibacterium salmoninarum was conducted using 3 different challenge methods in brackish and fresh water. bacterial isolation, elisa and pcr tests were used for detection of the bacterium in multiple organ samples. in an experiment, run for 34 wk in brackish water, infection was established by intraperitoneal injec ...201728357983
evaluation of chitinolytic activities and membrane integrity in gut tissues of arctic charr (salvelinus alpinus) fed fish meal and zygomycete biomass.chitinolytic activity, nutrient uptake and intestinal barrier functions were investigated in gut tissues of arctic charr (salvelinus alpinus) fed iso-nitrogenous diets based on fish meal, with or without inclusion of zygomycetes (rhizopus oryzae). we found that gut tissue of arctic charr had significant chitinase activity, of both endo- and exo-chitinase iso-forms. moreover, the distribution pattern along the gi tract of arctic charr differed between endo-chitinase and exo-chitinase. the endo-ch ...201424947208
piscine reovirus (prv) in wild atlantic salmon, salmo salar l., and sea-trout, salmo trutta l., in norway.this is the first comprehensive study on the occurrence and distribution of piscine reovirus (prv) in atlantic salmon, salmo salar l., caught in norwegian rivers. prv is a newly discovered reovirus associated with heart and skeletal muscle inflammation (hsmi), a serious and commercially important disease affecting farmed atlantic salmon in norway. a cross-sectional survey based on real-time rt-pcr screening of head kidney samples from wild, cultivated and escaped farmed atlantic salmon caught fr ...201323167652
erod activity in gill filaments of anadromous and marine fish as a biomarker of dioxin-like pollutants.the applicability of a gill filament-based ethoxyresorufin o-deethylase (erod) assay, originally developed in rainbow trout, was examined in atlantic salmon (salmo salar), arctic charr (salvelinus alpinus), atlantic cod (gadus morhua), saithe (pollachius virens) and spotted wolffish (anarhichas minor). all species but spotted wolffish showed strong erod induction in tip pieces of gill filaments following 48 h of exposure to waterborne beta-naphthoflavone. atlantic salmon parr, smolts held in fre ...200314659457
construction of aeromonas salmonicida subsp. achromogenes asap1-toxoid strains and study of their ability to induce immunity in arctic char, salvelinus alpinus l.the metalloendopeptidase asap1 is one of the major extracellular virulence factors of a. salmonicida subsp. achromogenes, expressed as a 37-kda pre-pro-peptide and processed to a 19-kda active peptide. the aim of this study was to construct mutant strains secreting an asap1-toxoid instead of asap1-wt, to study virulence of these strains and to test the potency of the asap1-toxoid bacterin and the recombinant asap1-toxoids to induce protective immunity in arctic char. two a. salmonicida mutants w ...201425271952
high-resolution ¹h magic angle spinning nmr spectroscopy of intact arctic char (salvelinus alpinus) muscle. quantitative analysis of n-3 fatty acids, epa and dha.the lipid and small metabolite profiles from intact muscles of arctic char were investigated using (1)h high-resolution magic angle spinning ((1)h hr-mas) nmr spectroscopy. not only the total n-3 fatty acid content but also the eicosapentaenoic acid (epa) and docosahexaenoic acid (dha) contents of the muscle were obtained from the (1)h hr-mas nmr spectra without pretreatment of the tissue or lipophilic extraction. a number of small metabolites could also be observed, where creatine/phosphocreati ...201020873863
innate and adaptive immune responses of arctic charr (salvelinus alpinus, l.) during infection with aeromonas salmonicida subsp. achromogenes and the effect of the asap1 toxin.aeromonas salmonicida subsp. achromogenes, the causative agent of atypical furunculosis in many fish species, secretes the toxic metalloendopeptidase asap1. this study aimed to analyze innate and adaptive immune parameters induced in arctic charr (salvelinus alpinus, l.) infected with wild type (wt) a. salmonicida subsp. achromogenes and its isogenic asap1 deletion mutant (asap1-deficient). head-kidney, liver and spleen were obtained from i.p. infected charr (wt, asap1-deficient), during a time ...201323811350
toxoid construction of asap1, a lethal toxic aspzincin metalloendopeptidase of aeromonas salmonicida subsp. achromogenes, and studies of its activity and processing.asap1 is a toxic aspzincin metalloendopeptidase secreted by the fish pathogen aeromonas salmonicida subsp. achromogenes. the protease is highly immunogenic and antibodies against asap1 evoke a passive protection against infection with a. salmonicida subsp. achromogenes. the protease is expressed as 37 kda pre-pro-protein and processed to an active enzyme of 19kda in a. salmonicida subsp. achromogenes. recombinant expression of asap1(rec) in e. coli results in a protease of 22 kda that is not sec ...201323031341
vaccination against furunculosis in arctic char: efficacy of a commercial vaccine.arctic char salvelinus alpinus are susceptible to furunculosis, a serious bacterial disease that affects the productivity of salmonid farms around the world. the objective of this laboratory study was to evaluate the efficacy of a commercially available vaccine against furunculosis in two strains of arctic char. labrador and nauyuk char were injected with aqua health furogen 2 or 0.9% nacl. at 87 and 108 d postvaccination, fish were challenged with aeromonas salmonicida by immersion. in both cha ...200626599045
handling and storage procedures have variable effects on fatty acid content in fishes with different lipid quantities.it is commonly assumed that the most accurate data on fatty acid (fa) contents are obtained when samples are analyzed immediately after collection. for logistical reasons, however, this is not always feasible and samples are often kept on ice or frozen at various temperatures and for diverse time periods. we quantified temporal changes of selected fa (μg fame per mg tissue dry weight) from 6 fish species subjected to 2 handling and 3 storage methods and compared them to fa contents from muscle t ...201627479304
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