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nocardiosis in freshwater reared chinook salmon (oncorhynchus tshawytscha).an investigation was conducted to identify the cause of mortalities in freshwater reared chinook salmon (oncorhynchus tshawytscha). mortalities occurred in juvenile salmon, at a salmon rearing facility in the south island of new zealand. the affected fish were from a pen inside the facility with no surrounding pens or other year classes affected.201728372487
a survey of microparasites present in adult migrating chinook salmon (oncorhynchus tshawytscha) in south-western british columbia determined by high-throughput quantitative polymerase chain reaction.microparasites play an important role in the demography, ecology and evolution of pacific salmonids. as salmon stocks continue to decline and the impacts of global climate change on fish populations become apparent, a greater understanding of microparasites in wild salmon populations is warranted. we used high-throughput, quantitative pcr (ht-qrt-pcr) to rapidly screen 82 adult chinook salmon from five geographically or genetically distinct groups (mostly returning to tributaries of the fraser r ...201728188649
evaluating signals of oil spill impacts, climate, and species interactions in pacific herring and pacific salmon populations in prince william sound and copper river, alaska.the exxon valdez oil spill occurred in march 1989 in prince william sound, alaska, and was one of the worst environmental disasters on record in the united states. despite long-term data collection over the nearly three decades since the spill, tremendous uncertainty remains as to how significantly the spill affected fishery resources. pacific herring (clupea pallasii) and some wild pacific salmon populations (oncorhynchus spp.) in prince william sound declined in the early 1990s, and have not r ...201728296895
modeling magnetic fields from a dc power cable buried beneath san francisco bay based on empirical measurements.the trans bay cable (tbc) is a ±200-kilovolt (kv), 400 mw 85-km long high voltage direct current (dc) buried transmission line linking pittsburg, ca with san francisco, ca (sf) beneath the san francisco estuary. the tbc runs parallel to the migratory route of various marine species, including green sturgeon, chinook salmon, and steelhead trout. in july and august 2014, an extensive series of magnetic field measurements were taken using a pair of submerged geometrics magnetometers towed behind a ...201626915084
method for somatic cell nuclear transfer in zebrafish.this chapter presents a detailed methodology for somatic cell nuclear transfer-cloning of zebrafish. we aim to place the reader in a virtual lab experience to assist acquisition of the technical skills required for reproducing the published protocol. all materials, including catalog numbers for reagents and techniques for their preparation, are provided. our protocols describe laser inactivation of egg chromosomes, the transfer of a cell through the oocyte micropyle, and spontaneous activation o ...201627443929
gamete-associated flavobacteria of the oviparous chinook salmon (oncorhynchus tshawytscha) in lakes michigan and huron, north america.flavobacterial diseases, caused by multiple members of the family flavobacteriaceae, elicit serious losses in wild and farmed fish around the world. flavobacteria are known to be transmitted horizontally; however, vertical transmission has been suspected but proven only for one fish-pathogenic flavobacterial species (e.g., flavobacterium psychrophilum). herein, we report on the isolation and molecular identification of multiple flavobacterium and chryseobacterium taxa from the ovarian fluid and ...201627350613
genetic diversity of flavobacterium psychrophilum isolates from three oncorhynchus spp. in the united states, as revealed by multilocus sequence typing.the use of a multilocus sequence typing (mlst) technique has identified the intraspecific genetic diversity of u.s. flavobacterium psychrophilum, an important pathogen of salmonids worldwide. prior to this analysis, little u.s. f. psychrophilum genetic information was known; this is of importance when considering targeted control strategies, including vaccine development. herein, mlst was used to investigate the genetic diversity of 96 f. psychrophilum isolates recovered from rainbow trout (onco ...201627016570
susceptibility of ocean- and stream-type chinook salmon to isolates of the l, u, and m genogroups of infectious hematopoietic necrosis virus (ihnv).this study examined the susceptibility of chinook salmon oncorhynchus tshawytscha to viral strains from the l, u, and m genogroups of infectious hematopoietic necrosis virus (ihnv) present in western north america. the goal of this investigation was to establish a baseline understanding of the susceptibility of ocean- and stream-type chinook salmon to infection and mortality caused by exposure to commonly detected strains of l, u, and m ihnv. the l ihnv strain tested here was highly infectious a ...201627596856
effects of temperature on renibacterium salmoninarum infection and transmission potential in chinook salmon, oncorhynchus tshawytscha (walbaum).renibacterium salmoninarum is a significant pathogen of salmonids and the causative agent of bacterial kidney disease (bkd). water temperature affects the replication rate of pathogens and the function of the fish immune system to influence the progression of disease. in addition, rapid shifts in temperature may serve as stressors that reduce host resistance. this study evaluated the effect of shifts in water temperature on established r. salmoninarum infections. we challenged chinook salmon wit ...201626449619
identification, library synthesis and anti-vibriosis activity of 2-benzyl-4-chlorophenol from cultures of the marine bacterium shewanella halifaxensis.summer gut syndrome (sgs) is caused by various vibrio bacterial species and can have negative effects on aquaculture farms worldwide. in new zealand, sgs is caused by vibrio harveyii infecting king salmon (oncorhynchus tshawytscha). to find leads for the prevention of sgs, we screened the inhibitory effects of 16 strains of shewanella upon v. harveyii growth in competitive solid phase cultures. the detailed investigation of shewanella halifaxensis irl548 revealed 2-benzyl-4-chlorophenol (1), a k ...201627185331
ichthyophonus parasite phylogeny based on its rdna structure prediction and alignment identifies six clades, with a single dominant marine type.despite their widespread, global impact in both wild and cultured fishes, little is known of the diversity, transmission patterns, and phylogeography of parasites generally identified as ichthyophonus. this study constructed a phylogeny based on the structural alignment of internal transcribed spacer (its) rdna sequences to compare ichthyophonus isolates from fish hosts in the atlantic and pacific oceans, and several rivers and aquaculture sites in north america, europe, and japan. structure of ...201627409236
the pacific white shrimp β-actin promoter: functional properties and the potential application for transduction system using recombinant baculovirus.a newly isolated pacific white shrimp (litopenaeus vannamei) beta-actin promoter sbap and its derivative compact construct sbap (enx) have recently been demonstrated to promote ectopic gene expression in vitro and in vivo. to further explore the potential transduction application, this newly isolated shrimp promoter sbap was comparatively tested with cytomegalovirus (cmv), simian virus 40 (sv40), polyhedrin (polh), and white spot syndrome virus immediate early gene 1 (wssv ie1) four constitutive ...201627177910
full-genome sequencing and confirmation of the causative agent of erythrocytic inclusion body syndrome in coho salmon identifies a new type of piscine orthoreovirus.erythrocytic inclusion body syndrome (eibs) causes mass mortality in farmed salmonid fish, including the coho salmon, onchorhynchus kisutchi, and chinook salmon, o. tshawytscha. the causative agent of the disease is a virus with an icosahedral virion structure, but this virus has not been characterized at the molecular level. in this study, we sequenced the genome of a virus purified from eibs-affected coho salmon. the virus has 10 dsrna genomic segments (l1, l2, l3, m1, m2, m3, s1, s2, s3, and ...201627788206
a polyprotein-expressing salmonid alphavirus replicon induces modest protection in atlantic salmon (salmo salar) against infectious pancreatic necrosis.vaccination is an important strategy for the control and prevention of infectious pancreatic necrosis (ipn) in farmed atlantic salmon (salmo salar) in the post-smolt stage in sea-water. in this study, a heterologous gene expression system, based on a replicon construct of salmonid alphavirus (sav), was used for in vitro and in vivo expression of ipn virus proteins. the large open reading frame of segment a, encoding the polyprotein nh2-pvp2-vp4-vp3-cooh, as well as pvp2, were cloned and expresse ...201525606973
effect of nanophyetus salmincola and bacterial co-infection on mortality of juvenile chinook salmon.the freshwater trematode nanophyetus salmincola has been demonstrated to impair salmonid immune function and resistance to the marine pathogen vibrio anguillarum, potentially resulting in ocean mortality. we examined whether infection by the parasite n. salmincola similarly increases mortality of juvenile chinook salmon oncorhynchus tshawytscha when they are exposed to the freshwater pathogens flavobacterium columnare or aeromonas salmonicida, two bacteria that juvenile salmonids might encounter ...201526671546
a review of fish lectins.lectins have been reported from various tissues of a diversity of fish species including japanese eel, conger eel, electric eel, bighead carp, gibel carp, grass carp, arabian gulf catfish, channel catfish, blue catfish, catfish, pike perch, perch, powan, zebrafish, toxic moray, cobia fish, steelhead trout, japanese trout, atlantic salmon, chinook salmon, olive rainbow smelt, rainbow smelt, white-spotted charr, tilapia, blue gourami, ayu, potca fish, spanish mackerel, gilt head bream, tench, roac ...201525929869
dietary exposure to individual polybrominated diphenyl ether congeners bde-47 and bde-99 alters innate immunity and disease susceptibility in juvenile chinook salmon.polybrominated diphenyl ethers (pbdes), used as commercial flame-retardants, are bioaccumulating in threatened pacific salmon. however, little is known of pbde effects on critical physiological functions required for optimal health and survival. bde-47 and bde-99 are the predominant pbde congeners found in chinook salmon collected from the pacific northwest. in the present study, both innate immunity (phagocytosis and production of superoxide anion) and pathogen challenge were used to evaluate h ...201525938634
testing of candidate non-lethal sampling methods for detection of renibacterium salmoninarum in juvenile chinook salmon oncorhynchus tshawytscha.non-lethal pathogen testing can be a useful tool for fish disease research and management. our research objectives were to determine if (1) fin clips, gill snips, surface mucus scrapings, blood draws, or kidney biopsies could be obtained non-lethally from 3 to 15 g chinook salmon oncorhynchus tshawytscha, (2) non-lethal samples could accurately discriminate between fish exposed to the bacterial kidney disease agent renibacterium salmoninarum and non-exposed fish, and (3) non-lethal samples could ...201525958804
flavobacterium psychrophilum infections in salmonid broodstock and hatchery-propagated stocks of the great lakes basin.bacterial coldwater disease (bcwd), caused by flavobacterium psychrophilum, threatens wild and propagated salmonids worldwide and leads to substantial economic losses. in addition to being horizontally transmitted, f. psychrophilum can be passed from infected parents to their progeny, furthering the negative impacts of this pathogen. in michigan, both feral and captive salmonid broodstocks are the gamete sources used in fishery propagation efforts. a 5-year study was initiated to follow the prev ...201526636411
occupancy modeling for improved accuracy and understanding of pathogen prevalence and dynamics.most pathogen detection tests are imperfect, with a sensitivity < 100%, thereby resulting in the potential for a false negative, where a pathogen is present but not detected. false negatives in a sample inflate the number of non-detections, negatively biasing estimates of pathogen prevalence. histological examination of tissues as a diagnostic test can be advantageous as multiple pathogens can be examined and providing important information on associated pathological changes to the host. however ...201525738709
infections by renibacterium salmoninarum and nanophyetus salmincola chapin are associated with reduced growth of juvenile chinook salmon, oncorhynchus tshawytscha (walbaum), in the northeast pacific ocean.we examined 1454 juvenile chinook salmon, oncorhynchus tshawytscha (walbaum), captured in nearshore waters off the coasts of washington and oregon (usa) from 1999 to 2004 for infection by renibacterium salmoninarum, nanophyetus salmincola chapin and skin metacercariae. the prevalence and intensities for each of these infections were established for both yearling and subyearling chinook salmon. two metrics of salmon growth, weight residuals and plasma levels of insulin-like growth factor-1, were ...201524720546
neoparamoeba perurans loses virulence during clonal culture.amoebic gill disease affects farmed salmonids and is caused by neoparamoeba perurans. clonal cultures of this amoeba have been used for challenge experiments, however the effect of long-term culture on virulence has not been investigated. here we show, using in vitro and in vivo methods, that a clone of n. perurans which was virulent 70 days after clonal culture lost virulence after 3 years in clonal culture. we propose that this is related either to the lack of attachment to the gills or the ab ...201526008963
aluminium oxide nanoparticles induced morphological changes, cytotoxicity and oxidative stress in chinook salmon (chse-214) cells.aluminium oxide nanoparticles (al2 o3 nps) are increasingly used in diverse applications that has raised concern about their safety. recent studies suggested that al2 o3 nps induced oxidative stress may be the cause of toxicity in algae, ceriodaphnia dubia, caenorhabditis elegans and danio rerio. however, there is paucity on the toxicity of al2 o3 nps on fish cell lines. the current study was aimed to investigate al2 o3 nps induced cytotoxicity, oxidative stress and morphological abnormality of ...201525875951
method to measure the force to pull and to break pin bones of fish.a texture measurement device was modified to measure the force required to pull pin bones from king salmon (oncorhynchus tshawytscha), snapper (pagrus auratus), and kahawai (arripis trutta). pulled bones were also subjected to tension to measure the breaking force. for all fish, the pulling force depended on the size of the fish, and on the length of the pin bone (p < 0.05). in general, larger fish required greater pulling force to remove pin bones. for example, fresh small salmon (about 1500 g ...201525604165
complexity of bioindicator selection for ecological, human, and cultural health: chinook salmon and red knot as case studies.there is considerable interest in developing bioindicators of ecological health that are also useful indicators for human health. yet, human health assessment usually encompasses physical/chemical exposures and not cultural well-being. in this paper, we propose that bioindicators can be selected for all three purposes. we use chinook or king salmon (oncorhynchus tshawytscha) and red knot (calidris canutus rufa, a sandpiper) as examples of indicators that can be used to assess human, ecological, ...201525666646
salmon blood plasma: effective inhibitor of protease-laden pacific whiting surimi and salmon mince.the effect of salmon plasma (sp) from chinook salmon on proteolytic inhibition was investigated. sp was found to inhibit both cysteine and serine proteases as well as protease extracted from pacific whiting muscle. sp was found to contain a 55kda cysteine protease inhibitor through sds-page inhibitor staining. freeze dried salmon plasma (fsp) and salmon plasma concentrated by ultrafiltration (csp) were tested for their ability to inhibit autolysis in pacific whiting surimi and salmon mince at co ...201525624255
effects of pyrethroid insecticides in urban runoff on chinook salmon, steelhead trout, and their invertebrate prey.pyrethroid insecticides can affect salmonids either indirectly through toxicity to their prey or directly by toxicity to the fish themselves. in support of a study on pyrethroid impacts to chinook salmon and steelhead trout in the american river (sacramento, california, usa), 96-h median effective concentration (ec50) and median lethal concentration (lc50) values for the pyrethroid bifenthrin were determined for taxa not traditionally used for toxicity testing but of interest as salmonid prey, i ...201525545717
predation on the invasive copepod, pseudodiaptomus forbesi, and native zooplankton in the lower columbia river: an experimental approach to quantify differences in prey-specific feeding rates.invasive planktonic crustaceans have become a prominent feature of aquatic communities worldwide, yet their effects on food webs are not well known. the asian calanoid copepod, pseudodiaptomus forbesi, introduced to the columbia river estuary approximately 15 years ago, now dominates the late-summer zooplankton community, but its use by native aquatic predators is unknown. we investigated whether three species of planktivorous fishes (chinook salmon, three-spined stickleback, and northern pikemi ...201526618851
flavobacterium spartansii sp. nov., a pathogen of fishes, and emended descriptions of flavobacterium aquidurense and flavobacterium araucananum.two strains (t16(t) and s12) of a gram-reaction-negative, rod-shaped, yellow-pigmented bacterium were recovered from kidneys of feral spawning adult chinook salmon (oncorhynchus tshawytscha) and the gills of captive-reared chinook salmon fingerlings suffering a mortality episode, respectively. polyphasic characterization revealed that these strains possessed gliding motility, contained a flexirubin-type pigment, proteolysed multiple substrates (i.e. gelatin, casein and elastin), and had a mean d ...201424096350
cooking fish is not effective in reducing exposure to perfluoroalkyl and polyfluoroalkyl substances.consumption of fish is considered a part of a healthy diet; however, health risks from fish consumption exist due to potential exposure to various contaminants accumulated in fish. cooking fish can reduce exposure to many organic chemicals in fish. similar results have been presented for low levels of perfluoroalkyl and polyfluoroalkyl substances (pfass), a class of contaminants of emerging concern, in grocery store fish. we examined the effectiveness of three cooking methods (i.e., baking, broi ...201424561272
in vitro cultivation model for heterosporis saurida (microsporidia) isolated from lizardfish, saurida undosquamis (richardson).heterosporis saurida is a microsporidian that infects lizardfish, saurida undosquamis (richardson, 1848), in the arabian sea. spores were isolated from infected lizardfish and used to infect derived fish cell lines: common carp brain (ccb), epithelioma papulosum cyprinid (epc), fathead minnow epithelial (fhm), rainbow trout gonad (rtg), bluegill fry (bf-2) and chinook salmon embryo (chse). non-fish cell lines were also tested that include: insect (sf-9), rabbit (rk-13) and african green monkey ( ...201423957717
genetic variation in bacterial kidney disease (bkd) susceptibility in lake michigan chinook salmon and its progenitor population from the puget sound.mass mortality events in wild fish due to infectious diseases are troubling, especially given the potential for long-term, population-level consequences. evolutionary theory predicts that populations with sufficient genetic variation will adapt in response to pathogen pressure. chinook salmon oncorhynchus tshawytscha were introduced into lake michigan in the late 1960s from a washington state hatchery population. in the late 1980s, collapse of the forage base and nutritional stress in lake michi ...201424689954
in vivo and in vitro phenotypic differences between great lakes vhsv genotype ivb isolates with sequence types vcg001 and vcg002.viral hemorrhagic septicemia virus (vhsv) is an aquatic rhabdovirus first recognized in farmed rainbow trout in denmark. in the past decade, a new genotype of this virus, ivb was discovered in the laurentian great lakes basin and has caused several massive die-offs in some of the 28 species of susceptible north american freshwater fishes. since its colonization of the great lakes, several closely related sequence types within genotype ivb have been reported, the two most common of which are vcg0 ...201425722533
the impact of temperature stress and pesticide exposure on mortality and disease susceptibility of endangered pacific salmon.anthropogenic stressors, including chemical contamination and temperature stress, may contribute to increased disease susceptibility in aquatic animals. specifically, the organophosphate pesticide malathion has been detected in surface waters inhabited by threatened and endangered salmon. in the presence of increasing water temperatures, malathion may increase susceptibility to disease and ultimately threaten salmon survival. this work examines the effect of acute and sublethal exposures to mala ...201424559935
differential response of the senegalese sole (solea senegalensis) mx promoter to viral infections in two salmonid cell lines.mx proteins are main effectors of the antiviral innate immune defence mediated by type i interferon (ifn i). the ifn i response is under a complex regulation; hence, one of the key issues in understanding virus-host interaction is the knowledge of the regulatory mechanisms governing this response. with this purpose, in this study chinook salmon embryo cells (chse-214) and rainbow trout gonad cells (rtg-2) were transiently transfected with a vector containing the luciferase reporter gene under th ...201425217803
salmonid alphavirus replication in mosquito cells: towards a novel vaccine production system.salmonid alphavirus (sav) causes pancreas disease and sleeping disease in atlantic salmon (salmo salar) and rainbow trout (oncorhynchus mykiss) and confers a major burden to the aquaculture industry. a commercial inactivated whole virus vaccine propagated in a salmon cell line at low temperature provides effective protection against sav infections. alphaviruses (family togaviridae) are generally transmitted between vertebrate hosts via blood-sucking arthropod vectors, typically mosquitoes. sav i ...201424418177
sensitivity and specificity of histology for diagnoses of four common pathogens and detection of nontarget pathogens in adult chinook salmon (oncorhynchus tshawytscha) in fresh water.histology is often underutilized in aquatic animal disease screening and diagnostics. the agreement between histological classifications of infection and results using diagnostic testing from the american fisheries society's blue book was conducted with 4 common salmon pathogens: aeromonas salmonicida, renibacterium salmoninarum, ceratomyxa shasta, and nanophyetus salmincola. adult chinook salmon (oncorhynchus tshawytscha) in oregon were evaluated, and agreement between tests was calculated. liv ...201323536613
polyphasic characterization of aeromonas salmonicida isolates recovered from salmonid and non-salmonid fish.michigan's fisheries rely primarily upon the hatchery propagation of salmonid fish for release in public waters. one limitation on the success of these efforts is the presence of bacterial pathogens, including aeromonas salmonicida, the causative agent of furunculosis. this study was undertaken to determine the prevalence of a. salmonicida in michigan fish, as well as to determine whether biochemical or gene sequence variability exists among michigan isolates. a total of 2202 wild, feral and hat ...201323444966
development and validation of a real-time pcr assay for the detection of aeromonas salmonicida.a real-time pcr assay using a molecular beacon was developed and validated to detect the vapa (surface array protein) gene in the fish pathogen, aeromonas salmonicida. the assay had 100% analytical specificity and analytical sensitivities of 5 ± 0 fg (dna), 2.2 × 10(4) ± 1 × 10(4) cfu g(-1) (without enrichment) and 40 ± 10 cfu g(-1) (with enrichment) in kidney tissue. the assay was highly repeatable and proved to be robust following equivalency testing using a different real-time pcr platform. f ...201323121198
virulence of viral hemorrhagic septicemia virus (vhsv) genotypes ia, iva, ivb, and ivc in five fish species.the susceptibility of yellow perch perca flavescens, rainbow trout oncorhynchus mykiss, chinook salmon o. tshawytscha, koi cyprinus carpio koi, and pacific herring clupea pallasii to 4 strains of viral hemorrhagic septicemia virus (vhsv) was assessed. fish were challenged via intraperitoneal injection with high (1 × 106 plaque-forming units, pfu) and low (1 × 103 pfu) doses of a european strain (genotype ia), and north american strains from the west coast (genotype iva), great lakes (genotype iv ...201324334352
molecular epidemiology of viral haemorrhagic septicaemia virus (vhsv) in british columbia, canada, reveals transmission from wild to farmed fish.viral haemorrhagic septicaemia virus (vhsv) is a fish pathogen found throughout the northern hemisphere and is capable of infecting and causing mortality in numerous marine and freshwater hosts. in the coastal waters of british columbia, canada, the virus has been detected for 20 yr with many occurrences of mass mortalities among populations of pacific herring clupea pallasii (valenciennes) and sardine sardinops sagax as well as detections among cultured atlantic salmo salar and chinook oncorhyn ...201323709462
toxicity of forest fire retardant chemicals to stream-type chinook salmon undergoing parr-smolt transformation.long-term fire retardants are used to prevent the spread of wildland fires. these products are normally applied by aircraft and are intended specifically for terrestrial application, but fire retardants have entered aquatic habitats by misapplication and/or accidental spills and have resulted in fish mortalities. the authors examined the toxicity of two fire retardant products, phos-chek 259f and lc-95a, to salmon undergoing parr-smolt transformation. yearling stream-type chinook salmon at the s ...201323161484
isolation of a novel gene from photobacterium damselae subsp. piscicida and analysis of the recombinant antigen as promising vaccine candidate.photobacterium damselae subsp. piscicida (pdp) is the causative agent of fish pasteurellosis, a bacterial disease causing important losses in marine aquaculture. vaccines against the pathogen can be a way to control the infection and avoid antibiotic treatments. however, a satisfactory protective vaccine against fish pasteurellosis is not commercially available. in this study, a biotechnogical approach based on reverse vaccinology has been used to identify potential vaccine candidates for the de ...201323219776
multilocus variable-number tandem-repeat genotyping of renibacterium salmoninarum, a bacterium causing bacterial kidney disease in salmonid fish.bacterial kidney disease (bkd), caused by renibacterium salmoninarum, is a bacterial disease of fish, which is both geographically widespread and difficult to control. previously, application of various molecular typing methods has failed to reliably discriminate between r. salmoninarum isolates originating from different host species and geographic areas. the current study aimed to utilize multilocus variable number tandem repeats (vntr) to investigate inter-strain variation of r. salmoninarum ...201324313994
bench-top validation testing of selected immunological and molecular renibacterium salmoninarum diagnostic assays by comparison with quantitative bacteriological culture.no gold standard assay exhibiting error-free classification of results has been identified for detection of renibacterium salmoninarum, the causative agent of salmonid bacterial kidney disease. validation of diagnostic assays for r. salmoninarum has been hindered by its unique characteristics and biology, and difficulties in locating suitable populations of reference test animals. infection status of fish in test populations is often unknown, and it is commonly assumed that the assay yielding th ...201323346868
cutthroat trout virus as a surrogate in vitro infection model for testing inhibitors of hepatitis e virus replication.hepatitis e virus (hev) is one of the most important causes of acute hepatitis worldwide. although most infections are self-limiting, mortality is particularly high in pregnant women. chronic infections can occur in transplant and other immune-compromised patients. successful treatment of chronic hepatitis e has been reported with ribavirin and pegylated interferon-alpha, however severe side effects were observed. we employed the cutthroat trout virus (ctv), a non-pathogenic fish virus with rema ...201323916729
pcr testing can be as accurate as culture for diagnosis of ichthyophonus hoferi in yukon river chinook salmon oncorhynchus tshawytscha .we evaluated the comparability of culture and pcr tests for detecting ichthyophonus in yukon river chinook salmon oncorhynchus tshawytscha from field samples collected at 3 locations (emmonak, chena, and salcha, alaska, usa) in 2004, 2005, and 2006. assuming diagnosis by culture as the 'true' infection status, we calculated the sensitivity (correctly identifying fish positive for ichthyophonus), specificity (correctly identifying fish negative for ichthyophonus), and accuracy (correctly identify ...201323836767
brain acetylcholinesterase activity in shiner perch (cymatogaster aggregata) and juvenile chinook salmon (oncorhynchus tshawytscha) after application of carbaryl to control burrowing shrimp within willapa bay, washington.carbaryl has been applied in willapa bay, washington, for five decades to control burrowing shrimp (neotrypaea californiensis and upogebia pugettensis) on commercial oyster (crassostrea gigas) beds. concerns about effects on nontarget species, including fishes, have led to restrictions in use despite a lack of data on in situ exposure. we measured brain acetylcholinesterase (ache) activity in adult shiner perch (cymatogaster aggregata) and juvenile chinook salmon (oncorhynchus tshawytscha) after ...201324042340
public willingness to pay for recovering and downlisting threatened and endangered marine species.nonmarket valuation research has produced economic value estimates for a variety of threatened, endangered, and rare species around the world. although over 40 value estimates exist, it is often difficult to compare values from different studies due to variations in study design, implementation, and modeling specifications. we conducted a stated-preference choice experiment to estimate the value of recovering or downlisting 8 threatened and endangered marine species in the united states: loggerh ...201222827248
epidemiological investigation of renibacterium salmoninarum in three oncorhynchus spp. in michigan from 2001 to 2010.bacterial kidney disease (bkd) has caused mortalities and chronic infections in wild and farm-raised salmonids throughout the world. in the laurentian great lakes of north america, bkd was associated with several large-scale mortality events of oncorhynchus spp. throughout the 1980s and 1990s. in response to these mortality events, the state of michigan implemented several enhanced biosecurity measures to limit the occurrence of bkd in state-operated hatcheries and gamete-collection weirs. the o ...201222874662
fugu double u6 promoter-driven long double-stranded rna inhibits proliferation of viral hemorrhagic septicemia virus (vhsv) in fish cell lines.a long double-stranded rna (dsrna)-producing vector driven by fugu double u6 promotors, in which the two promoters were arranged in a head-to-head fashion, was newly constructed. to determine whether the dna-vector-based long dsrnas can induce sequence-specific rna interference (rnai), epithelioma papulosum cyprini (epc) cells and chinook salmon embryonic (chse-214) cells were transfected with the long dsrna vector targeting the g gene of vhsv, and its effect on expression of the g gene and vira ...201222398916
isolation and molecular characterization of a novel infectious pancreatic necrosis virus strain in returning atlantic salmon salmo salar from the connecticut river, usa.after 22 years of negative viral screening results, the viral pathogen infectious pancreatic necrosis virus (ipnv) was isolated from the ovarian fluid of two pooled samples of returning connecticut river atlantic salmon salmo salar during the 2007 spawning season at richard cronin national salmon station (rcnss), hadley, massachusetts. cytopathic effect was observed in chinook salmon embryo (chse-214) cells, and ipnv was confirmed by reverse transcriptase-polymerase chain reaction (rt-pcr). sequ ...201222838076
infectivity study of streptococcus phocae to seven fish and mammalian cell lines by confocal microscopy.streptococcus phocae is a beta-haemolytic bacterium that causes systemic infections in atlantic salmon, salmo salar l., cultured in southern chile and also in seals. in this study, the host-pathogen interaction between s. phocae and seven types of cell lines (fish and mammalian) was examined using an indirect fluorescent antibody and confocal microscopy (cm). chinook salmon embryo (chse-214), epithelioma papulosum cyprini (epc), salmon head kidney (shk-1) and atlantic salmon kidney were used as ...201222524521
development of an in vitro system to measure the sensitivity to the antiviral mx protein of fish viruses.mx is a structural protein, induced by type i interferon (ifn), with direct antiviral properties. in fish the inherent contribution of mx protein to viral protection is unknown. the transgenic chinook salmon embryonic (chse)-tof cell line was genetically modified to express the rainbow trout mx (rbtmx1) protein under the control of the tetracycline derivative, doxycycline (dox). two clones chse-tof-mx8 and chse-tof-mx10 were isolated and characterised by qpcr. the level of resistance to infectio ...201222405879
early interactions of edwardsiella ictaluri, with pangasianodon catfish and its invasive ability in cell lines.commercial pangasianodon catfish production is heavily impacted by bacillary necrosis of pangasius (bnp) caused by edwardsiella ictaluri. this study aimed to investigate the early bacterium-host interactions following immersion challenge and to compare the retrieved data with the invasion ability of the used isolates in fish cell lines. firstly, pangasianodon hypophthalmus fingerlings were challenged via immersion using e. ictaluri isolate ho2 or 223. at different times post inoculation, fish we ...201222422551
a cytotoxicity and comparative antibacterial study on the effect of zataria multiflora boiss, trachyspermum copticum essential oils, and enrofloxacin on aeromonas hydrophila.this study designed to test the antibacterial potency of enrofloxacin (enr) and essential oils from zataria multiflora boiss (zeo) and trachyspermum copticum (teo) on aeromonas hydrophila.201225050249
reproductive success of captively bred and naturally spawned chinook salmon colonizing newly accessible habitat.captively reared animals can provide an immediate demographic boost in reintroduction programs, but may also reduce the fitness of colonizing populations. construction of a fish passage facility at landsburg diversion dam on the cedar river, wa, usa, provided a unique opportunity to explore this trade-off. we thoroughly sampled adult chinook salmon (oncorhynchus tshawytscha) at the onset of colonization (2003-2009), constructed a pedigree from genotypes at 10 microsatellite loci, and calculated ...201223467446
Bacterial infections of Chinook salmon, Oncorhynchus tshawytscha (Walbaum), returning to gamete collecting weirs in Michigan.Herein, we describe the prevalence of bacterial infections in Chinook salmon, Oncorhynchus tshawytscha (Walbaum), returning to spawn in two tributaries within the Lake Michigan watershed. Ten bacterial genera, including Renibacterium, Aeromonas, Carnobacterium, Serratia, Proteus, Pseudomonas, Hafnia, Salmonella, Shewanella and Morganella, were detected in the kidneys of Chinook salmon (n = 480) using culture, serological and molecular analyses. Among these, Aeromonas salmonicida was detected at ...201222168454
circulating salmon 28- and 22-kda insulin-like growth factor binding proteins (igfbps) are co-orthologs of igfbp-1.circulating insulin-like growth factor binding proteins (igfbps) play pivotal roles in stabilizing igfs and regulating their availability to target tissues. in the teleost circulation, three major igfbps are typically detected by ligand blotting with molecular masses around 20-25, 28-32 and 40-45kda. however, their identity is poorly established and often confused. we previously identified salmon 22- and 41-kda forms as igfbp-1 and -2b, respectively. in the present study, we cloned the cdna of 2 ...201121888908
The use of a real-time PCR primer/probe set to observe infectivity of Yersinia ruckeri in Chinook salmon, Oncorhynchus tshawytscha (Walbaum), and steelhead trout, Oncorhynchus mykiss (Walbaum).Yersinia ruckeri is the causative agent of enteric redmouth disease (ERM), a common pathogen affecting aquaculture facilities and implicated in large losses of cultured fish. Fisheries scientists continue to gain a greater understanding of the disease and the pathogen by investigating methods of identification and pre- and post-infection treatment. In this study, a real-time PCR probe set for Y. ruckeri was developed to detect daily changes in the bacterial load during pathogen challenges. Two s ...201121916903
in situ biomonitoring of caged, juvenile chinook salmon (oncorhynchus tshawytscha) in the lower duwamish waterway.contaminated sediments may have wide-ranging impacts on human and ecological health. a series of in situ caged exposure studies using juvenile chinook salmon was conducted in the lower duwamish waterway (ldw). chemical analysis of sediment, water, and fish tissue were completed. additionally, in 2004, dna adducts in hepatic and gill tissues were measured. gills contained significantly higher dna adducts at stations b2 and b4, prompting further analysis of gills in 2006 and 2007. fluorescent arom ...201121906759
sphaerothecum destruens pathology in cyprinids.sphaerothecum destruens is a significant intracellular parasite of fish which has caused disease and mortalities in cultured north american chinook salmon oncorhynchus tshawytscha and atlantic salmon salmo salar. several hosts for s. destruens have been identified within the salmonidae family, and the histopathology of the infection can differ between hosts. recently, s. destruens has been associated with the most invasive cyprinid species in europe, topmouth gudgeon pseudorasbora parva. accurat ...201121848122
carnobacterium maltaromaticum infections in feral oncorhynchus spp. (family salmonidae) in michigan.members of the genus oncorhynchus were introduced from the pacific northwest to the laurentian great lakes basin and now constitute one of its most commercially and ecologically valuable fisheries. recently, infections by a group of gram-positive atypical lactobacilli belonging to the genus carnobacterium have been detected in feral and captive oncorhynchus spp. broodstock, some of which were associated with mortalities. out of 1564 rainbow and steelhead trout (o. mykiss), coho salmon (o. kisutc ...201122068485
development and validation of real-time pcr for the detection of yersinia ruckeri.yersiniosis (enteric red mouth disease) is a contagious bacterial disease caused by yersinia ruckeri, which primarily affects salmonids. a real-time pcr assay using a molecular beacon has been developed and validated to improve the detection of the causative biotypes of y. ruckeri. the assay, which targets the glna (glutamine synthetase) gene, proved to have 100% analytical specificity and analytical sensitivities of 5 fg and 3 × 10(3)  cfu g(-1) for dna and seeded kidney tissue, respectively. ...201122175801
the strength and timing of the mitochondrial bottleneck in salmon suggests a conserved mechanism in vertebrates.in most species mitochondrial dna (mtdna) is inherited maternally in an apparently clonal fashion, although how this is achieved remains uncertain. population genetic studies show not only that individuals can harbor more than one type of mtdna (heteroplasmy) but that heteroplasmy is common and widespread across a diversity of taxa. females harboring a mixture of mtdnas may transmit varying proportions of each mtdna type (haplotype) to their offspring. however, mtdna variants are also observed t ...201121655224
human influence on the spatial structure of threatened pacific salmon metapopulations.to remain viable, populations must be resilient to both natural and human-caused environmental changes. we evaluated anthropogenic effects on spatial connections among populations of chinook salmon (oncorhynchus tshawytscha) and steelhead (o. mykiss) (designated as threatened under the u.s. endangered species act) in the lower columbia and willamette rivers. for several anthropogenic-effects scenarios, we used graph theory to characterize the spatial relation among populations. we plotted varian ...201121797926
an evaluation of the influence of stock origin and out-migration history on the disease susceptibility and survival of juvenile chinook salmon.various methods have been developed to mitigate the adverse effects of the federal columbia river power system on juvenile pacific salmon out-migrating through the columbia river basin. in this study, we found that hatchery-reared spring chinook salmon oncorhynchus tshawytscha in the river are in varying degrees of health, which may affect delayed mortality and the assessment of the effectiveness of management actions to recover listed stocks (e.g., barging fish downstream versus leaving fish in ...201121699135
survey of pathogens in hatchery chinook salmon with different out-migration histories through the snake and columbia rivers.the operation of the federal columbia river power system (fcrps) has negatively affected threatened and endangered salmonid populations in the pacific northwest. barging snake river spring chinook salmon oncorhynchus tshawytscha through the fcrps is one effort to mitigate the effect of the hydrosystem on juvenile salmon out-migration. however, little is known about the occurrence and transmission of infectious agents in barged juvenile salmon relative to juvenile salmon that remain in-river to n ...201121834329
self-sustaining populations, population sinks or aggregates of strays: chum (oncorhynchus keta) and chinook salmon (oncorhynchus tshawytscha) in the wood river system, alaska.small populations can provide insights into ecological and evolutionary aspects of species distributions over space and time. in the wood river system in alaska, usa, small aggregates of chinook (oncorhynchus tshawytscha) and chum salmon (o. keta) spawn in an area dominated by sockeye salmon (o. nerka). our objective was to determine whether these chinook and chum salmon are reproductively isolated, self-sustaining populations, population sinks that produce returning adults but receive immigrati ...201122026559
surface properties of streptococcus phocae strains isolated from diseased atlantic salmon, salmo salar l.streptococcus phocae is an emerging pathogen for chilean atlantic salmon, salmo salar, but the factors determining its virulence are not yet elucidated. in this work, cell surface-related properties such as hydrophobicity and haemagglutination, adhesion to mucus and cell lines, capsule detection, survival and biofilm formation in skin mucus and serum resistance of the isolates responsible for outbreaks in atlantic salmon and seals were examined. adhesion to hydrocarbons and the results of salt a ...201121306587
residues of pbdes in northeastern pacific marine fish: evidence for spatial and temporal trends.in the flesh (skinless fillet) of chinook, chum, coho, pink, and sockeye salmon (oncorhynchus tshawytscha, o. keta, o. kisutch, o. gorbuscha, and o. nerka, respectively), sablefish (anoplopoma fimbria) and walleye pollock (theragra chalcogramma) from several sites in the northeast pacific sampled between 2002 and 2008, tetra- and pentabrominated diphenyl ethers (bdes) (bde 47, 49, 99, and 100) dominated the congener distribution. chinook and sablefish contained the highest concentrations, follow ...201121360729
comparison and evaluation of renibacterium salmoninarum quantitative pcr diagnostic assays using field samples of chinook and coho salmon.renibacterium salmoninarum is a gram-positive bacterium causing bacterial kidney disease (bkd) in susceptible salmonid fishes. several quantitative pcr (qpcr) assays to measure r. salmoninarum infection intensity have been reported, but comparison and evaluation of these assays has been limited. here, we compared 3 qpcr primer/probe sets for detection of r. salmoninarum in field samples of naturally exposed chinook and coho salmon first identified as positive by nested pcr (npcr). additional sam ...201121381519
distance-based population classification software using mean-field annealing.we describe a distance-based clustering method using a proximity matrix of genetic distances to partition populations into genetically similar groupings. the optimization heuristic mean-field annealing (mfa) was used to find locally optimal solutions where exhaustive search was not possible. to illustrate this method, we analysed both simulated and real data sets. simulated data indicated that mfa successfully differentiated population groups, even with small f(st) values, as long as there was s ...201121429108
development of 54 novel single-nucleotide polymorphism (snp) assays for sockeye and coho salmon and assessment of available snps to differentiate stocks within the columbia river.single-nucleotide polymorphisms (snps) have potential for broad application in population and conservation genetics, but availability of these markers is limited in many nonmodel species. in this study, genomic and expressed sequence tagged (est) sequences from closely related salmonids (chinook salmon and rainbow trout) were used to design primers for amplification and sequencing of sockeye (oncorhynchus nerka) and coho (oncorhynchus kisutch) salmon dna for snp discovery. one hundred and six pr ...201121429160
purification and characterization of a rhamnose-binding chinook salmon roe lectin with antiproliferative activity toward tumor cells and nitric oxide-inducing activity toward murine macrophages.in this study, a rhamnose-binding lectin from the roe of chinook salmon (oncorhynchus tshawytscha) was purified and characterized, and its biological activities were examined in several model systems. chinook salmon roe lectin had a molecular mass of 30 kda and agglutinated rabbit and bovine erythrocytes. the hemagglutination activity of the lectin was not affected by metal ions. the lectin was stable up to 70 °c and between ph 4 and ph 11. chinook salmon roe lectin did not exert antifungal acti ...201121456624
a novel member of the family hepeviridae from cutthroat trout (oncorhynchus clarkii).beginning in 1988, the chinook salmon embryo (chse-214) cell line was used to isolate a novel virus from spawning adult trout in the state of california, usa. termed the cutthroat trout (oncorhynchus clarkii) virus (ctv), the small, round virus was not associated with disease, but was subsequently found to be present in an increasing number of trout populations in the western usa, likely by a combination of improved surveillance activities and the shipment of infected eggs to new locations. here ...201121458509
comparative evaluation of molecular diagnostic tests for nucleospora salmonis and prevalence in migrating juvenile salmonids from the snake river, usa.nucleospora salmonis is an intranuclear microsporidian that primarily infects lymphoblast cells and contributes to chronic lymphoblastosis and a leukemia-like condition in a range of salmonid species. the primary goal of this study was to evaluate the prevalence of n. salmonis in out-migrating juvenile hatchery and wild chinook salmon oncorhynchus tshawytscha and steelhead o. mykiss from the snake river in the u.s. pacific northwest. to achieve this goal, we first addressed the following concern ...201121699133
species-specific differences and structure-activity relationships in the debromination of pbde congeners in three fish species.previous studies have suggested that there may be species-specific differences in the metabolism of polybrominated diphenyl ethers (pbdes) among different fish species. in this study, we investigated the in vitro hepatic metabolism of eleven individual pbde congeners (tri- through decabdes) in three different fish species: rainbow trout (oncorhynchus mykiss), common carp (cyprinus carpio), and chinook salmon (o. tschwatcha). in addition, we evaluated the influence of pbde structural characterist ...201121291240
automated sperm head morphology analyzer for open-source software.sperm head morphology has been identified as a characteristic that can be used to predict a male's semen quality. in the present study, we have developed an automated sperm head morphology analysis (asma) plug-in for open-source imagej software (http://rsbweb.nih.gov/ij/). we describe the plug-in's functionality, and confirm its validity for sperm head morphology analysis using fish sperm. sperm head morphological measurements (length and width) made with the asma plug-in did not differ from man ...201121962916
conservation of the chromatophore pigment response.toxicant sensing technology has evolved to include biological sensors, such as cell-based biosensors, which rely on viable cells to convey a measurable physiological signal. chromatophores are a class of pigment cells that have been investigated as cell-based biosensors. we report the characterization of oncorhynchus tshawytscha melanophores and describe the melanophore pigment response to neurotransmitters in terms of pigment area occupied. compared with the previously described model, betta sp ...201020809546
interpreting dual elisa and qpcr data for bacterial kidney disease of salmonids.although there are a variety of methods available for the detection of renibacterium salmoninarum, the causative agent of bacterial kidney disease in salmon and trout, the enzyme-linked immunosorbent assay (elisa) is probably the most widely used method. however, elisa measures bacterial antigen, which does not necessarily reflect the number of cells present. we hypothesized that dual analysis of kidney tissue by elisa and a quantitative real-time polymerase chain reaction assay (qpcr) would pro ...201021387990
effects of epinephrine and norepinephrine on glucose release from chinook salmon (oncorhynchus tshawytscha) liver incubated in vitro.the effects of two catecholamines, epinephrine (ep) and norepinephrine (ne), on carbohydrate metabolism were studied by incubating chinook salmon liver in vitro. basal release of glucose over the course of a 5-h incubation was 7.93 +/- 1.70 mumol/g dry weight. both ep and ne (2 x 10(-7) m) stimulated glucose release rapidly during the first hour. after 5 h, ep and ne significantly increased glucose release over basal levels to 43.55 +/- 9.01 and 32.75 +/- 6.17 mumol/g dry weight, respectively. e ...20102904478
transcriptional differences between triploid and diploid chinook salmon (oncorhynchus tshawytscha) during live vibrio anguillarum challenge.understanding how organisms function at the level of gene expression is becoming increasingly important for both ecological and evolutionary studies. it is evident that the diversity and complexity of organisms are not dependent solely on their number of genes, but also the variability in gene expression and gene interactions. furthermore, slight differences in transcription control can fundamentally affect the fitness of the organism in a variable environment or during development. in this stud ...201019707232
gene expression profiling and environmental contaminant assessment of migrating pacific salmon in the fraser river watershed of british columbia.the health and physiological condition of anadromous salmon is of concern as their upriver migration requires navigation of human-impacted waterways and metabolism of stored energy reserves containing anthropogenic contaminants. such factors may affect reproductive success of fish stocks. this study investigates chemical contaminant burdens and select gene expression profiles in pacific sockeye (oncorhynchus nerka) and chinook (oncorhynchus tshawytscha) salmon which traverse the fraser river wat ...201019811841
in vitro markers for virulence in yersinia ruckeri.in this study, different traits that have been associated with bacterial virulence were studied in yersinia ruckeri. two isolates that had been shown to cause disease and mortality in experimentally infected rainbow trout were compared with five avirulent isolates. both virulent isolates showed high adhesion to gill and intestinal mucus of rainbow trout, whereas the majority of non-virulent strains demonstrated significantly lower adhesion. a decrease in adherence capability following bacterial ...201019878528
disparate infection patterns of ceratomyxa shasta (myxozoa) in rainbow trout (oncorhynchus mykiss) and chinook salmon (oncorhynchus tshawytscha) correlate with internal transcribed spacer-1 sequence variation in the parasite.ceratomyxa shasta is a virulent myxosporean parasite of salmon and trout in the pacific northwest of north america. the parasite is endemic in the klamath river, oregon/california, where a series of dams prevent movement of fish hosts between the upper and lower parts of the basin. ceratomyxa shasta exhibits a range of infection patterns in different fish species above and below the dams. we hypothesised that the variations in infection and disease are indicators that different strains of the pa ...201019895812
differentially expressed genes following persistent infection with infectious pancreatic necrosis virus in vitro and in vivo.the mechanisms of viral persistence of infectious pancreatic necrosis virus (ipnv) are not well understood. in this study we have used a model of ipnv persistently infected chse (chinook salmon embryonic) cells as correlate of persistent infection in fish focusing on differentially expressed genes using subtractive hybridization (ssh). selected genes were also analyzed by quantitative real-time pcr (qpcr) in persistently infected parr of atlantic salmon. persistent infection was established by g ...201020152904
disease susceptibility of salmon exposed to polybrominated diphenyl ethers (pbdes).the health effects of the flame retardant polybrominated diphenyl ethers (pbdes) in fish are not well understood. to determine the potential effects of this ubiquitous contaminant class on fish health, juvenile subyearling chinook salmon (oncorhynchus tshawytscha) were fed a diet that reflected the pbde congeners found in the stomach contents of subyearling chinook salmon collected from the highly urbanized and industrialized lower willamette river in the columbia river basin of north america. t ...201020207027
invasion of ceratomyxa shasta (myxozoa) and comparison of migration to the intestine between susceptible and resistant fish hosts.the myxozoan parasite ceratomyxa shasta infects salmonids causing ceratomyxosis, a disease elicited by proliferation of the parasite in the intestine. this parasite is endemic to the pacific northwest of north america and salmon and trout strains from endemic river basins show increased resistance to the parasite. it has been suggested that these resistant fish (i) exclude the parasite at the site of invasion and/or (ii) prevent establishment in the intestine. using parasites pre-labeled with a ...201020385137
the amino terminus of the salmonid alphavirus capsid protein determines subcellular localization and inhibits cellular proliferation.salmonid alphavirus (sav) is the most divergent member of the family togaviridae and constitutes a threat to farming of salmonid fish in europe. here, we report cloning, expression and preliminary functional analysis of the capsid protein of sav, confirming it to be expressed as an approximately 31-kda protein in infected cells. the protein localizes strictly to the cytoplasm in chinook salmon embryo cells, and either to the nucleus or cytoplasm in bluegill fry cells. an expression study of full ...201020556445
pathological and immunological responses associated with differential survival of chinook salmon following renibacterium salmoninarum challenge.chinook salmon oncorhynchus tshawytscha are highly susceptible to renibacterium salmoninarum, the causative agent of bacterial kidney disease (bkd). previously we demonstrated that introduced chinook salmon from lake michigan, wisconsin (wi), usa, have higher survival following r. salmoninarum challenge relative to the progenitor stock from green river, washington, usa. in the present study, we investigated the pathological and immunological responses that are associated with differential surviv ...201020597428
spatial, temporal and host factors structure the ceratomyxa shasta (myxozoa) population in the klamath river basin.the myxozoan parasite ceratomyxa shasta is a virulent pathogen of salmonid fish in the klamath river, oregon/california, usa. we previously defined four principal genotypes of the parasite (o, i, ii, iii) based on a trinucleotide repeat (atc)(0-3) in internal transcribed spacer region 1 sequences. genotypes occur in sympatry and show marked host preference: i in chinook salmon (oncorhynchus tschawytscha) and ii in non-native rainbow trout (o. mykiss). in the present study, we sequenced the paras ...201020601174
color photographic index of fall chinook salmon embryonic development and accumulated thermal units.knowledge of the relationship between accumulated thermal units and developmental stages of chinook salmon embryos can be used to determine the approximate date of egg fertilization in natural redds, thus providing insight into oviposition timing of wild salmonids. however, few studies have documented time to different developmental stages of embryonic chinook salmon and no reference color photographs are available. the objectives of this study were to construct an index relating developmental s ...201020686709
[incomplete congruence between morphobiological characters and sex-specific molecular markers in pacific salmons: 1. analysis of discrepancy in five species of the genus oncorhynchus].the congruence between molecular markers, identifying the presence of the y chromosome, and secondary sexual characters was examined in asian populations of five pacific salmon species: pink salmon (oncorhynchus gorbuscha), chum salmon (o. keta), sockeye salmon (o. nerka), chinook salmon (o. tschawytsha), and sima (o. masou). it was demonstrated that in all species examined, the presence or absence of sex-specific molecular markers was to a considerable degree congruent with secondary sexual cha ...201020795502
development of infectious cdna clones of salmonid alphavirus subtype 3.abstract:201020858233
antiviral function of tilapia hepcidin 1-5 and its modulation of immune-related gene expressions against infectious pancreatic necrosis virus (ipnv) in chinook salmon embryo (chse)-214 cells.antimicrobial peptides, small cysteine-rich molecules, play vital roles in host defense mechanisms against pathogen infection. recently, tilapia hepcidin (th)1-5, was characterized, and its antimicrobial functions against several pathogens were reported. herein, we investigated the antiviral functions of th1-5 against infectious pancreatic necrosis virus (ipnv) in chinook salmon embryo (chse)-214 cells. the presence of th1-5 enhanced the survival of chse-214 cells infected with ipnv. additionall ...201020863896
potential of the melanophore pigment response for detection of bacterial toxicity.chromatophore cells have been investigated as potential biodetectors for function-based detection of chemically and biologically toxic substances. oncorhynchus tshawytscha (chinook salmon) melanophores, a chromatophore cell type containing brown pigment, rapidly detect the salmonid pathogens aeromonas salmonicida, yersinia ruckeri, and flavobacterium psychrophilum and the human pathogen bacillus cereus.201020952639
basis of acoustic discrimination of chinook salmon from other salmons by echolocating orcinus orca.the "resident" ecotype of killer whales (orcinus orca) in the waters of british columbia and washington state have a strong preference for chinook salmon even in months when chinook comprise less than about 10% of the salmon population. the foraging behavior of killer whales suggests that they depend on echolocation to detect and recognize their prey. in order to determine possible cues in echoes from salmon species, a series of backscatter measurements were made at the applied physics laborator ...201020968392
simulating fishery-induced evolution in chinook salmon: the role of gear, location, and genetic correlation among traits.adaptation to human-modified ecosystems has been implicated in changing the life history of a number of wild animal populations, potentially contributing to their collapse. fishing may be an important evolutionary force that can change the distribution of fitness-related traits; however, the magnitude and direction of the evolutionary response may be influenced by different management strategies. most phenotypic traits subject to human-induced selection are simultaneously influenced by the envir ...201021049881
mortality threshold for juvenile chinook salmon oncorhynchus tshawytscha in an epidemiological model of ceratomyxa shasta.the myxozoan parasite ceratomyxa shasta is a significant pathogen of juvenile chinook salmon oncorhynchus tshawytscha in the klamath river, california, usa. this parasite requires 2 hosts to complete its life cycle: a freshwater polychaete (manayunkia speciosa) and a salmonid. the complex life cycle and large geographic area where infection occurs make it difficult to monitor and manage ceratomyxosis. we present a model for ceratomyxosis-induced mortality in o. tshawytscha, from which parameters ...201021290897
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