| salmon pancreas disease virus, an alphavirus infecting farmed atlantic salmon, salmo salar l. | a 5.2-kb region at the 3' terminus of the salmon pancreas disease virus (spdv) rna genome has been cloned and sequenced. the nucleotide and predicted amino acid sequences show that spdv shares considerable organizational and sequence identity to members of the genus alphavirus within the family togaviridae. the spdv structural proteins encoded by the 5.2-kb region contain a number of unique features when compared to other sequenced alphaviruses. based on cleavage site homologies, the predicted s ... | 1999 | 10191183 |
| rainbow trout sleeping disease virus is an atypical alphavirus. | sleeping disease (sd) is currently a matter of concern for salmonid fish farmers in most parts of the world. a viral etiology of sd has recently been suspected, since virus-like particles have been observed in infected rainbow trout cells. in salmonid-derived cell lines, the maximal rate of virus production was observed at 10 degrees c, while little virus was produced at 14 degrees c. through biochemical, physicochemical, and morphological studies, sd virus (sdv) was shown to be an enveloped vir ... | 2000 | 10590104 |
| biochemical characterization of salmon pancreas disease virus. | salmon pancreas disease virus (spdv) has been shown to cause severe economic losses in farmed atlantic salmon (salmo salar) and has been reported to occur in europe, scandinavia and the united states. this paper describes the biochemical characterization of spdv in terms of its rna and protein composition. spdv was purified by precipitation from infected chinook salmon embryo (chse-214) cell-culture supernatant and sucrose density-gradient centrifugation. fractions containing virus were identifi ... | 2000 | 10675419 |
| an rt-pcr-based method for the diagnosis of the sleeping disease virus in experimentally and naturally infected salmonids. | the sleeping disease (sd) of rainbow trout (oncorhynchus mykiss) is a worldwide disease for which the causative agent, the sleeping disease virus (sdv), has been recently characterized as an atypical alphavirus (villoing et al. 2000). up to now, no diagnostic tools were available and thus no epidemiological studies have been undertaken to evaluate the occurrence of this disease on the field. we present in this paper a sensitive and highly specific 1 working day method, which allows the detection ... | 2000 | 10785859 |
| sequence requirements for sindbis virus subgenomic mrna promoter function in cultured cells. | the sindbis virus minimal subgenomic mrna promoter (spanning positions -19 to +5 relative to the subgenomic mrna start site) is approximately three- to sixfold less active than the fully active -98 to +14 promoter region. we identified two elements flanking the -19 to +5 region which increase its transcription to levels comparable to the -98 to +14 region. these elements span positions -40 to -20 and +6 to +14 and act synergistically to enhance transcription. nine different virus libraries were ... | 2001 | 11264340 |
| arbovirus of marine mammals: a new alphavirus isolated from the elephant seal louse, lepidophthirus macrorhini. | a novel alphavirus was isolated from the louse lepidophthirus macrorhini, collected from southern elephant seals, mirounga leonina, on macquarie island, australia. the virus displayed classic alphavirus ultrastructure and appeared to be serologically different from known australasian alphaviruses. nearly all macquarie island elephant seals tested had neutralizing antibodies against the virus, but no virus-associated pathology has been identified. antarctic division personnel who have worked exte ... | 2001 | 11287559 |
| isolation of salmon pancreas disease virus (spdv) in cell culture and its ability to protect against infection by the 'wild-type' agent. | a scottish salmon pancreas disease virus (spdv) has been isolated and its optimum growth conditions determined. although several fish cell lines have been tested, successful culture was achieved only with chse-214 cells. cytopathic effects were observed after 5 days. the highest virus titres, calculated by microtitration assay, were reached at 15 degrees c. after 7-9 days post-inoculation, chse-214 cell supernatants contained between 10(7)-10(5) tcid50 ml(-1) the cultured isolate is chloroform- ... | 2001 | 11556480 |
| evolutionary relationships and systematics of the alphaviruses. | partial e1 envelope glycoprotein gene sequences and complete structural polyprotein sequences were used to compare divergence and construct phylogenetic trees for the genus alphavirus. tree topologies indicated that the mosquito-borne alphaviruses could have arisen in either the old or the new world, with at least two transoceanic introductions to account for their current distribution. the time frame for alphavirus diversification could not be estimated because maximum-likelihood analyses indic ... | 2001 | 11581380 |
| production and characterisation of monoclonal antibodies to salmon pancreas disease virus. | six mouse monoclonal antibodies (mabs) specific to salmon pancreas disease virus (spdv) were produced following immunisation with purified virus preparations. these mabs and 2 mabs resulting from an earlier investigation were characterised. none of the mabs possessed virus neutralising activity but all reacted with 4 geographically different spdv isolates as determined by indirect immunofluorescence. three mabs produced positive immunostaining with western blots of spdv proteins. the 4h1 mab rea ... | 2001 | 11678224 |
| pathogenesis and immune response in atlantic salmon (salmo salar l.) parr experimentally infected with salmon pancreas disease virus (spdv). | atlantic salmon parr were injected intraperitoneally with salmon pancreas disease virus (spdv) grown on chse-214 cells. the viraemia, the histopathological changes in target organs and some immune parameters were taken at intervals up to 30 days post-infection (dpi). the earliest kind of lesion was necrosis of exocrine pancreas, appearing as soon as 2 dpi. it progressed towards complete tissue breakdown at 9 dpi before resolving gradually. concurrent to this necrosis, a strong inflammatory respo ... | 2002 | 11866132 |
| comparison of two aquatic alphaviruses, salmon pancreas disease virus and sleeping disease virus, by using genome sequence analysis, monoclonal reactivity, and cross-infection. | cell culture isolates of salmon pancreas disease virus (spdv) of farmed atlantic salmon and sleeping disease virus (sdv) of rainbow trout were compared. excluding the poly(a) tracts, the genomic nucleotide sequences of spdv and sdv rnas include 11,919 and 11,900 nucleotides, respectively. phylogenetic analysis places spdv and sdv between the new world viruses of venezuelan equine encephalitis virus and eastern equine encephalitis virus and the old world viruses of aura virus and sindbis virus. w ... | 2002 | 12021349 |
| detection of infectious salmon anaemia virus (isav) by in situ hybridisation. | an in situ hybridisation method was developed to detect infectious salmon anaemia virus (isav) in fixed tissues from atlantic salmon salmo salar l. three dna probes detected isav in heart, liver, kidney, spleen, caeca, and mid-gut from infected farmed atlantic salmon obtained from a natural outbreak of isa. the strongest signals were obtained using probe s8, from segment 8 of isav. hybridisation was most prominent in the endothelial cells of heart tissue. the probes reacted specifically with isa ... | 2002 | 12180700 |
| haemorrhagic smolt syndrome (hss) in norway: pathology and associated virus-like particles. | atlantic salmon salmo salar pre-smolt, smolt and post-smolt, with clinical signs of haemorrhagic smolt syndrome (hss) have been found in several locations along the norwegian coast (rogaland to troms). affected fish had pale gills and bleeding at the fin bases, but seemed to be in good physical condition with no obvious weight loss. the internal organs and body cavity showed distinct bleedings. petechiae were found on the gastrointestinal tract, swim bladder and peritoneum, visceral adipose tiss ... | 2003 | 12718466 |
| a rapid immunoperoxidase-based virus neutralization assay for salmonid alphavirus used for a serological survey in northern ireland. | a modified virus neutralization (vn) assay was developed to replace an existing assay read on the presence or absence of virus-induced cytopathic effect (cpe). the modified assay used a monoclonal antibody to salmon pancreas disease virus as the first layer of an immunoperoxidase (ipx)-based immunostaining technique to detect viral growth. the ipx-based vn assay required only 3 days to perform, and the adoption of a 96-well microtitre format facilitated a high throughput of samples requiring sma ... | 2003 | 12946010 |
| detection and antigenic characterization of salmonid alphavirus isolates from sera obtained from farmed atlantic salmon, salmo salar l., and farmed rainbow trout, oncorhynchus mykiss (walbaum). | a simple method of detecting the presence of the salmonid alphaviruses (savs), salmon pancreas disease virus (spdv) and sleeping disease virus (sdv), from serum samples is described. using a 96-well tissue-culture plate format, test sera are diluted in medium and added to chinook salmon embryo (chse-214) cells. after incubation for 3 days at 15 degrees c, plates are fixed and stained using a monoclonal antibody (mab)-based immunoperoxidase (ipx) detection system, and virus-infected cells are obs ... | 2004 | 15009240 |
| longitudinal serological surveys of atlantic salmon, salmo salar l., using a rapid immunoperoxidase-based neutralization assay for salmonid alphavirus. | longitudinal serological surveys for salmon pancreas disease virus (spdv), the causal agent of pancreas disease (pd), were conducted on multiple caged populations of atlantic salmon, salmo salar l., on two farms over a 77-week period (farm 1, freshwater and marine stages) and a 36-week period (farm 2, marine stage only), using a microtitre-based virus neutralization (vn) assay. collected sera were also screened for viraemia with spdv, and pancreas, heart and muscle tissues were examined for lesi ... | 2005 | 15960660 |
| sensitive and specific detection of salmonid alphavirus using real-time pcr (taqman). | pancreas disease is responsible for major economic losses in the european salmonid farming industry. it was previously believed that a single subtype (salmon pancreas disease virus) of the virus species salmonid alphavirus (sav) was responsible for all outbreaks of pancreas disease in the uk and norway. however, the recent discovery that pancreas disease in norway is caused by a new and distinct subtype of salmonid alphavirus, exclusively found in norway, has advocated the need for better diagno ... | 2006 | 16202457 |
| nucleotide sequence variation in salmonid alphaviruses from outbreaks of salmon pancreas disease and sleeping disease. | we compared 18 salmonid alphaviruses (sav) including the reference f93-125 salmon pancreas disease virus (spdv) and s49p sleeping disease virus (sdv) isolates by nucleotide sequence analyses of regions within the e1, nsp4 and nsp3 genes, and found these to comprise 3 distinct groups, which we have designated subtypes 1, 2 and 3: subtype 1, which comprised savs with sequences closely similar to the reference spdv isolate, included savs from pancreas disease (pd) outbreaks in farmed salmon in irel ... | 2005 | 16231635 |
| recovery of a recombinant salmonid alphavirus fully attenuated and protective for rainbow trout. | sleeping disease virus (sdv) is a member of the new salmonid alphavirus genus within the togaviridae family. the single-stranded rna genome of sdv is 11,894 nucleotides long, excluding the 3' poly(a) tail. a full-length cdna has been generated; the cdna was fused to a hammerhead ribozyme sequence at the 5' end and inserted into a transcription plasmid (pcdna3) backbone, yielding psdv. by transfection of psdv into fish cells, recombinant sdv (rsdv) was successfully recovered. demonstration of the ... | 2006 | 16571825 |
| virological, serological and histopathological evaluation of fish strain susceptibility to experimental infection with salmonid alphavirus. | pancreas disease (pd) of farmed atlantic salmon salmo salar l., which is caused by an alphavirus known as salmon pancreas disease virus (spdv), can have serious economic consequences. an epidemiological survey carried out in ireland in 2003 indicated that within individual farms there were significant differences in the susceptibility of different strains of farmed atlantic salmon to infection with spdv, as measured by levels of clinical disease and mortality. the aim of this preliminary study w ... | 2006 | 17140135 |
| alphavirus infections in salmonids--a review. | the first alphavirus to be isolated from fish was recorded in 1995 with the isolation of salmon pancreas disease virus from atlantic salmon, salmo salar l., in ireland. subsequently, the closely related sleeping disease virus was isolated from rainbow trout, oncorhynchus mykiss (walbaum), in france. more recently norwegian salmonid alphavirus (sav) has been isolated from marine phase production of atlantic salmon and rainbow trout in norway. these three viruses are closely related and are now co ... | 2007 | 17718707 |
| a recombinant chse-214 cell line expressing an mx1 promoter-reporter system responds to both interferon type i and type ii from salmonids and represents a versatile tool to study the ifn-system in teleost fish. | a transgenic cell line for the detection of salmon interferons (ifns) has been established. it is based on a chse-214 cell line containing a reporter construct expressing firefly luciferase under the control of the rainbow trout promoter for the ifn-induced mx1 gene. this cell line, named chse-mx10, showed ifn-induced luciferase expression after more than 80 passages, confirming the stability of this cell line. interestingly, the mx promoter was shown to respond to both salmon ifn-alpha/beta and ... | 2007 | 17804253 |
| the dynamic envelope of a fusion class ii virus. e3 domain of glycoprotein e2 precursor in semliki forest virus provides a unique contact with the fusion protein e1. | in alphaviruses, here represented by semliki forest virus, infection requires an acid-responsive spike configuration to facilitate membrane fusion. the creation of this relies on the chaperone function of glycoprotein e2 precursor (p62) and its maturation cleavage into the small external e3 and the membrane-anchored e2 glycoproteins. to reveal how the e3 domain of p62 exerts its control of spike functions, we determine the structure of a p62 cleavage-impaired mutant virus particle (sql) by elect ... | 2008 | 18596032 |
| discovery of frameshifting in alphavirus 6k resolves a 20-year enigma. | the genus alphavirus includes several potentially lethal human viruses. additionally, species such as sindbis virus and semliki forest virus are important vectors for gene therapy, vaccination and cancer research, and important models for virion assembly and structural analyses. the genome encodes nine known proteins, including the small '6k' protein. 6k appears to be involved in envelope protein processing, membrane permeabilization, virion assembly and virus budding. in protein gels, 6k migrat ... | 2008 | 18822126 |
| a structural and functional perspective of alphavirus replication and assembly. | alphaviruses are small, spherical, enveloped, positive-sense ssrna viruses responsible for a considerable number of human and animal diseases. alphavirus members include chikungunya virus, sindbis virus, semliki forest virus, the western, eastern and venezuelan equine encephalitis viruses, and the ross river virus. alphaviruses can cause arthritic diseases and encephalitis in humans and animals and continue to be a worldwide threat. the viruses are transmitted by blood-sucking arthropods, and re ... | 2009 | 19722838 |
| characterization of untranslated regions of the salmonid alphavirus 3 (sav3) genome and construction of a sav3 based replicon. | salmonid alphavirus (sav) causes disease in farmed salmonid fish and is divided into different genetic subtypes (sav1-6). here we report the cloning and characterization of the 5'- and 3'- untranslated regions (utr) of a sav3 isolated from atlantic salmon in norway. the sequences of the utrs are very similar to those of sav1 and sav2, but single nucleotide polymorphisms are present, also in the 3' - conserved sequence element (3'-cse). prediction of the rna secondary structure suggested putative ... | 2009 | 19860871 |
| alpha interferon and not gamma interferon inhibits salmonid alphavirus subtype 3 replication in vitro. | salmonid alphavirus (sav) is an emerging virus in salmonid aquaculture, with sav-3 being the only subtype found in norway. until now, there has been little focus on the alpha interferon (ifn-alpha)-induced antiviral responses during virus infection in vivo or in vitro in fish. the possible involvement of ifn-gamma in the response to sav-3 is also not known. in this study, the two ifns were cloned and expressed as recombinant proteins (recombinant ifn-alpha [rifn-alpha] and rifn-gamma) and used f ... | 2010 | 20573808 |
| development of infectious cdna clones of salmonid alphavirus subtype 3. | abstract: | 2010 | 20858233 |
| a comparative study of marine salmonid alphavirus subtypes 1-6 using an experimental cohabitation challenge model. | a comparative challenge study of six marine isolates representing subtypes 1-6 of salmonid alphavirus (salmon pancreas disease virus, genus alphavirus, family togaviridae) was conducted in atlantic salmon in a fresh water cohabitation trial. histopathological lesions typical of pancreas disease were observed with all subtypes, and virus was re-isolated from serum of cohabitant fish in each case. using a virus neutralization (vn) test neutralizing salmonid alphavirus (sav) subtype 1 strain f93-12 ... | 2011 | 21294751 |
| the contribution of molecular epidemiology to the understanding and control of viral diseases of salmonid aquaculture. | abstract: molecular epidemiology is a science which utilizes molecular biology to define the distribution of disease in a population (descriptive epidemiology) and relies heavily on integration of traditional (or analytical) epidemiological approaches to identify the etiological determinants of this distribution. the study of viral pathogens of aquaculture has provided many exciting opportunities to apply such tools. this review considers the extent to which molecular epidemiological studies hav ... | 2011 | 21466673 |
| evolutionary genetics and vector adaptation of recombinant viruses of the western equine encephalitis antigenic complex provides new insights into alphavirus diversity and host switching. | western equine encephalitis virus (weev), highlands j virus (hjv), and fort morgan virus (fmv) are the sole representatives of the wee antigenic complex of the genus alphavirus, family togaviridae, that are endemic to north america. all three viruses have their ancestry in a recombination event involving eastern equine encephalitis virus (eeev) and a sindbis (sin)-like virus that gave rise to a chimeric alphavirus that subsequently diversified into the present-day weev, hjv, and fmv. here, we pr ... | 2014 | 25463613 |
| in- silico exploration of thirty alphavirus genomes for analysis of the simple sequence repeats. | the compilation of simple sequence repeats (ssrs) in viruses and its analysis with reference to incidence, distribution and variation would be instrumental in understanding the functional and evolutionary aspects of repeat sequences. present study encompasses the analysis of ssrs across 30 species of alphaviruses. the full length genome sequences, assessed from ncbi were used for extraction and analysis of repeat sequences using imex software. the repeats of different motif sizes (mono- to penta ... | 2014 | 25606453 |
| a genome-wide analysis of rna pseudoknots that stimulate efficient -1 ribosomal frameshifting or readthrough in animal viruses. | programmed -1 ribosomal frameshifting (prf) and stop codon readthrough are two translational recoding mechanisms utilized by some rna viruses to express their structural and enzymatic proteins at a defined ratio. efficient recoding usually requires an rna pseudoknot located several nucleotides downstream from the recoding site. to assess the strategic importance of the recoding pseudoknots, we have carried out a large scale genome-wide analysis in which we used an in-house developed program to d ... | 2013 | 24298557 |
| experimental piscine alphavirus rna recombination in vivo yields both viable virus and defective viral rna. | rna recombination in non-segmented rna viruses is important for viral evolution and documented for several virus species through in vitro studies. here we confirm viral rna recombination in vivo using an alphavirus, the sav3 subtype of salmon pancreas disease virus. the virus causes pancreas disease in atlantic salmon and heavy losses in european salmonid aquaculture. atlantic salmon were injected with a sav3 6k-gene deleted cdna plasmid, encoding a non-viable variant of sav3, together with a he ... | 2016 | 27805034 |
| a 6k-deletion variant of salmonid alphavirus is non-viable but can be rescued through rna recombination. | pancreas disease (pd) of atlantic salmon is an emerging disease caused by salmonid alphavirus (sav) which mainly affects salmonid aquaculture in western europe. although genome structure of sav has been characterized and each individual viral protein has been identified, the role of 6k protein in viral replication and infectivity remains undefined. the 6k protein of alphaviruses is a small and hydrophobic protein which is involved in membrane permeabilization, protein processing and virus buddin ... | 2014 | 25009976 |
| a review of intra- and extracellular antigen delivery systems for virus vaccines of finfish. | vaccine efficacy in aquaculture has for a long time depended on evaluating relative percent survival and antibody responses after vaccination. however, current advances in vaccine immunology show that the route in which antigens are delivered into cells is deterministic of the type of adaptive immune response evoked by vaccination. antigens delivered by the intracellular route induce mhc-i restricted cd8+ responses while antigens presented through the extracellular route activate mhc-ii restrict ... | 2015 | 26065009 |
| replication of west nile virus, rabensburg lineage in mammalian cells is restricted by temperature. | the genus flavivirus currently consists of approximately 80 single-strand positive-sense rna viruses. these replicate in a range of hosts including myriad vertebrate, insect, and tick species. as a consequence of this broad host range, the majority of flaviviruses can be propagated in most vertebrate and insect cell cultures. this ability to infect arthropods and vertebrates usually is essential for maintenance of these viruses in nature. but recently, there has been the discovery of a number of ... | 2012 | 23241081 |
| relationship between viral dose and outcome of infection in atlantic salmon, salmo salar l., post-smolts bath-challenged with salmonid alphavirus subtype 3. | salmonid alphavirus subtype 3 (sav3) causes pancreas disease (pd) and adversely affects salmonid aquaculture in europe. a better understanding of disease transmission is currently needed in order to manage pd outbreaks. here, we demonstrate the relationship between viral dose and the outcome of sav3 infection in atlantic salmon post-smolts using a bath challenge model. fish were challenged at 12 °c with 3 different sav3 doses; 139, 27 and 7 tcid50 l(-1) of seawater. a dose of as little as 7 tcid ... | 2016 | 27760562 |
| experimental piscine orthoreovirus infection mediates protection against pancreas disease in atlantic salmon (salmo salar). | viral diseases are among the main challenges in farming of atlantic salmon (salmo salar). the most prevalent viral diseases in norwegian salmon aquaculture are heart and skeletal muscle inflammation (hsmi) caused by piscine orthoreovirus (prv), and pancreas disease (pd) caused by salmonid alphavirus (sav). both prv and sav target heart and skeletal muscles, but sav additionally targets exocrine pancreas. prv and sav are often present in the same locations and co-infections occur, but the effect ... | 2016 | 27769313 |
| vaccination against pancreas disease in atlantic salmon, salmo salar l., reduces shedding of salmonid alphavirus. | salmon pancreas disease virus, often referred to as salmonid alphavirus (sav), causes pancreas disease (pd) in european salmonids. sav transmits horizontally from fish shedding virus into the water and ocean currents are believed to be a main contributor of viral spread between marine farms. vaccination against pd is previously shown to reduce mortality and severity of clinical pd. in this study, we demonstrate that vaccination against pd significantly reduces viral shedding from infected indivi ... | 2016 | 27496170 |
| atlantic salmon (salmo salar l.) post-smolts challenged two or nine weeks after seawater-transfer show differences in their susceptibility to salmonid alphavirus subtype 3 (sav3). | pancreas disease (pd), caused by salmonid alphavirus (sav), is an important disease affecting salmonid aquaculture. it has been speculated that atlantic salmon post-smolts are more prone to infections in the first few weeks following seawater- transfer. after this period of seawater acclimatization, the post-smolts are more robust and better able to resist infection by pathogens. here we describe how we established a bath immersion (bi) model for sav subtype 3 (sav3) in seawater. we also report ... | 2016 | 27068518 |
| pathological pigmentation in cardiac tissues of atlantic salmon (salmo salar l.) with cardiomyopathy syndrome. | it is widely accepted that melanin formation may play an immunologic role in invertebrates and ectothermic vertebrates. in farmed atlantic salmon, cardiomyopathy syndrome (cms) is a common viral disease associated with severe cardiac inflammation that may be accompanied by heavy melanisation of the heart. by the use of histology, laser capture microdissection and transcription analysis of tyrosinase genes, we here show that this melanisation is linked to de novo melanogenesis by melanomacrophage ... | 2013 | 24219276 |
| salmonid alphavirus glycoprotein e2 requires low temperature and e1 for virion formation and induction of protective immunity. | salmonid alphavirus (sav; also known as salmon pancreas disease virus; family togaviridae) causes pancreas disease and sleeping disease in atlantic salmon and rainbow trout, respectively, and poses a major burden to the aquaculture industry. sav infection in vivo is temperature-restricted and progeny virus is only produced at low temperatures (10-15 °c). using engineered sav replicons we show that viral rna replication is not temperature-restricted suggesting that the viral structural proteins d ... | 2014 | 25269093 |
| immune parameters correlating with reduced susceptibility to pancreas disease in experimentally challenged atlantic salmon (salmo salar). | two strains of atlantic salmon (salmon salar) with different susceptibility to infectious salmon anaemia (isa) were challenged with salmon pancreas disease virus (spdv), the etiological agent of salmon pancreas disease (pd), by cohabitation. serum and tissues were sampled at 0, 1, 3, 6 and 8 weeks post-challenge. experimental challenge with sav did not cause mortality, but virus loads and assessment of histopathology indicated that the fish more resistant to isav (isahi) also was more resistant ... | 2013 | 23306092 |
| liquid fat, a potential abiotic vector for horizontal transmission of salmonid alphavirus? | viral diseases represent serious challenge in marine farming of atlantic salmon (salmo salar l). pancreas disease (pd) caused by a salmonid alphavirus (sav) is by far the most serious in northern europe. to control pd, it is necessary to identify virus transmission routes. one aspect to consider is whether the virus is transported as free particles or associated with potential vectors. farmed salmonids have high lipid content in their tissue which may be released into the environment from decomp ... | 2016 | 25952607 |
| cross-sectional study to investigate the presence of salmon pancreas disease virus in wild and feral fish populations in 10 lakes, los lagos region, chile. | | 2015 | 24382013 |
| estimation of the reproduction number of salmon pancreas disease virus subtype 3 in homogeneously mixed populations of norwegian farmed atlantic salmon. | the reproduction number (r) of salmon pancreas disease (pd) was estimated within homogeneously mixing populations (within-cage) of norwegian farmed atlantic salmon (salmo salar l.) based on data collected during pd epidemics from 10 cages at 2 farming sites. two approaches were used: (a) estimation of an overall reproduction number (r(cmd)) and a time-dependent reproduction number (r(t)) using mortality records during pd epidemics, and (b) estimating the reproduction number during the early stag ... | 2013 | 23810623 |
| natural infection of atlantic salmon (salmo salar l.) with salmonid alphavirus 3 generates numerous viral deletion mutants. | salmon pancreas disease virus (spdv) also referred to as salmonid alphavirus (sav) is a virus causing pancreas disease in atlantic salmon (salmo salar l.) and rainbow trout (oncorhynchus mykiss). although the virus causes an economically important disease, relatively few full-length genome sequences of sav strains are currently available. here, we report full-length genome sequences of nine sav3 strains from sites farming atlantic salmon geographically spread along the norwegian coastline. the v ... | 2013 | 23704276 |
| comparison of complete polyprotein sequences of two isolates of salmon alphavirus (sav) type i and their behaviour in a salmonid cell line. | salmon pancreas disease virus is an alphavirus (family togaviridae) affecting mainly atlantic salmon (salmo salar l.). both polyprotein sequences of the scottish isolate (sav4640) were determined and compared with those of irish isolate savf93-125. high amino acid sequence similarity (99.4 %) was found. six amino acid deletions were found in the e2 gene of sav4640. savf93-125 demonstrated a high viral load in culture despite high mx expression. approximately 50 % of cells infected with savf93-12 ... | 2013 | 23595129 |
| transmission dynamics of pancreas disease (pd) in a norwegian fjord: aspects of water transport, contact networks and infection pressure among salmon farms. | pancreas disease (pd) in marine salmon farming is caused by salmon pancreas disease virus (spdv). virus survival, infection pressure and contact networks among farms influence the potential of pd to spread. the present study aims to explore contact networks and infection pressure and their ability to explain transmission dynamics of pd in a norwegian fjord. in this study, we included all records of pd by subtype 3 (spdv3) in the study population from the first reported in august 2006 to the last ... | 2014 | 23452114 |
| detection of salmon pancreas disease virus in the faeces and mucus of atlantic salmon, salmo salar l., by real-time rt-pcr and cell culture following experimental challenge. | | 2012 | 22924477 |
| transcription of reference genes used for quantitative rt-pcr in atlantic salmon is affected by viral infection. | relative quantification using rt-qpcr is a widely used method for transcription profiling. transcript levels of target genes in fish after experimental infection is often reported without documentation of stably transcribed reference genes. we present results demonstrating that transcription of typically used reference genes in atlantic salmon is not stable during experimental infection with salmon pancreas disease virus (spdv). transcript levels 0 to 6 weeks after challenge revealed statistical ... | 2011 | 21314970 |
| use of salmon cardiac primary cultures (scpcs) of different genotypes for comparative kinetics of mx expression, viral load and ultrastructure pathology, after infection with salmon pancreas disease virus (spdv). | in vitro fish based models have been extensively applied in human biomedical research but, paradoxically, less frequently in the research of fish health issues. farmed atlantic salmon can suffer from several viral conditions affecting the heart. therefore, species-specific, cardiac in vitro models may represent a useful tool to help further understanding and management of these diseases. the mechanisms underlying genotype based resistance are complex and usually rely on a combined effect of elem ... | 2018 | 29102629 |