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1.
J Fish Dis ; 40(4): 507-516, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-27593619

RESUMO

Rainbow trout, Oncorhynchus mykiss (Walbaum), are able to raise a protective immune response against Aeromonas salmonicida subsp. salmonicida (AS) following injection vaccination with commercial vaccines containing formalin-killed bacteria, but the protection is often suboptimal under Danish mariculture conditions. We elucidated whether protection can be improved by increasing the concentration of antigen (formalin-killed bacteria) in the vaccine. Rainbow trout juveniles were vaccinated by intraperitoneal (i.p.) injection with a bacterin of Aeromonas salmonicida subsp. salmonicida strain 090710-1/23 in combination with Vibrio anguillarum serotypes O1 and O2a supplemented with an oil adjuvant. Three concentrations of AS antigens were applied. Fish were subsequently challenged with the homologous bacterial strain administered by perforation of the tail fin epidermis and 60-s contact with live A. salmonicida bacteria. The infection method proved to be efficient and could differentiate efficacies of different vaccines. It was shown that protection and antibody production in exposed fish were positively correlated to the AS antigen concentration in the vaccine.


Assuntos
Aeromonas salmonicida/imunologia , Antígenos de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Doenças dos Peixes/prevenção & controle , Infecções por Bactérias Gram-Negativas/veterinária , Vacinação/veterinária , Adjuvantes Imunológicos/administração & dosagem , Animais , Doenças dos Peixes/microbiologia , Infecções por Bactérias Gram-Negativas/microbiologia , Infecções por Bactérias Gram-Negativas/prevenção & controle , Injeções Intraperitoneais/veterinária , Oncorhynchus mykiss , Vibrio/imunologia
3.
Dis Aquat Organ ; 44(1): 1-6, 2001 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-11253869

RESUMO

The sequences of gene segments 2 and 8 from 10 different isolates of infectious salmon anaemia virus (ISAV) sampled in Norway, Canada and Scotland between 1987 and 1999 were determined and compared. Pairwise comparisons revealed a high degree of homology between the European isolates, with identities of 98 to 100% for both genes examined. The Canadian isolate showed identities of 84 and 87 to 88% with the European isolates for the nucleotide sequence of segments 2 and 8, respectively. Phylogenetic analyses were performed to establish the interrelationship between the European virus isolates. The evolutionary rate based on 4 Norwegian isolates clustered together in the analysis of segment 2 was calculated to be 0.96 x 10(-3) nucleotides site(-1) yr(-1). On the basis of this mutation rate it was estimated that the Norwegian Glesvaer 90 and Canadian Bay of Fundy 97 isolates diverged around 1900, which coincides with transportation of salmonids between Europe and North America starting in the late nineteenth century.


Assuntos
Doenças dos Peixes/virologia , Infecções por Orthomyxoviridae/veterinária , Orthomyxoviridae/classificação , Salmo salar , Sequência de Aminoácidos , Substituição de Aminoácidos , Animais , Aquicultura , Canadá , Células Cultivadas , Dados de Sequência Molecular , Noruega , Orthomyxoviridae/química , Orthomyxoviridae/genética , Infecções por Orthomyxoviridae/virologia , Filogenia , RNA Viral/química , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Escócia
4.
Dis Aquat Organ ; 47(2): 119-28, 2001 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-11775793

RESUMO

Infectious salmon anemia (ISA) is caused by a virus that probably belongs to the Orthomyxoviridae and was first recorded in Norway in 1984. The disease has since spread along the Norwegian coast and has later been found in Canada, Scotland, the Faroe Islands, Chile, and the USA. This study presents sequence variation of the hemagglutinin gene from 37 ISA virus isolates, viz. one isolate from Scotland, one from Canada and 35 from Norway. The hemagglutinin gene contains a highly polymorphic region (HPR), which together with the rest of the gene sequence provides a good tool for studies of epizootics. The gene shows temporal and geographical sequence variation, where certain areas are dominated by distinct groups of isolates. Evidence of transmission of ISA virus isolates within and between regions is given. It is suggested that the hemagglutinin gene from different isolates may recombine. Possible recombination sites are found within the HPR and in the 5'-end flanking region close to the HPR.


Assuntos
Doenças dos Peixes/virologia , Hemaglutininas Virais/genética , Infecções por Orthomyxoviridae/veterinária , Orthomyxoviridae/genética , Recombinação Genética , Salmão , Anemia/epidemiologia , Anemia/veterinária , Anemia/virologia , Animais , Sequência de Bases , Doenças dos Peixes/epidemiologia , Doenças dos Peixes/transmissão , Variação Genética , Novo Brunswick/epidemiologia , Noruega/epidemiologia , Orthomyxoviridae/isolamento & purificação , Infecções por Orthomyxoviridae/epidemiologia , Infecções por Orthomyxoviridae/transmissão , Infecções por Orthomyxoviridae/virologia , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Escócia/epidemiologia , Alinhamento de Sequência/veterinária
5.
Dis Aquat Organ ; 40(1): 9-18, 2000 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-10785858

RESUMO

The emergence of infectious salmon anaemia virus (ISAV) in Canada and Scotland and frequent new outbreaks of the disease in Norway strongly suggest that there are natural reservoirs for the virus. The main host for the ISA virus is probably a fish occurring in the coastal area, most likely a salmonid fish. Since sea trout is an abundant species along the Norwegian coast, common in areas where ISA outbreaks occur, and possibly a life-long carrier of the ISA virus, a study was initiated to evaluate reverse transcriptase polymerase chain reaction (RT-PCR) for diagnosis of the virus in experimentally infected trout. Several tissues (kidney, spleen, heart and skin) were collected from the trout during a 135 d period. The following diagnostic methods for detection of the ISA virus were compared: cell culture (Atlantic Salmon Kidney, ASK cells), challenge of disease-free salmon with blood from the infected trout, and RT-PCR. The RT-PCR was the most sensitive of these methods. With the help of this technique it was possible to pick out positive individuals throughout the experimental period of 135 d. Challenge of disease-free salmon were more sensitive than cell culture (ASK cells). These 2 latter methods require use of the immunofluorescent antibody test (IFAT) or RT-PCR for verification of presence of ISA virus.


Assuntos
Doenças dos Peixes/diagnóstico , Infecções por Orthomyxoviridae/veterinária , Truta/virologia , Animais , Células Cultivadas , Transmissão de Doença Infecciosa , Feminino , Doenças dos Peixes/transmissão , Técnica Indireta de Fluorescência para Anticorpo/veterinária , Rim/virologia , Infecções por Orthomyxoviridae/diagnóstico , Infecções por Orthomyxoviridae/transmissão , Reação em Cadeia da Polimerase/veterinária , Salmo salar , Salmão/virologia , Sensibilidade e Especificidade
6.
Scand J Immunol ; 50(2): 202-10, 1999 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-10447926

RESUMO

A gene homologous to the IgD heavy chain (delta) gene in channel catfish (Ictalurus punctatus) was found 0.9 kb downstream of the IgM heavy chain (mu) gene in Atlantic salmon (Salmo salar). As in catfish, the first constant mu exon is spliced into the delta transcripts. In agreement with the tetraploid ancestry of the salmonid fish family there are two highly similar delta genes in Atlantic salmon. Characterization of these genes showed that they encode seven 'unique' Ig domains, three of which are tandem duplicated, i.e. like delta1-(delta2-delta3-delta4)*-(delta2- delta3-delta4)-delta5-delta6-d elta7. Sequence analysis indicates that delta1-delta7 arose from two duplication events. Accordingly, salmon delta can be reduced to a unit of three Ig domains corresponding to the three C-terminal domains of a prototypic Ig molecule. The ancestral three-domain unit is apparently best conserved in delta1-delta5-delta6. Phylograms indicate a relationship between teleost and mammalian IgD mainly because of the similarity between the teleost delta5 and human delta2. The corresponding domain in mouse IgD has been deleted during evolution. The teleost delta1 and delta6 sequences are most similar to domains of other non-IgM isotypes, including those in cartilaginous fishes.


Assuntos
Imunoglobulina D/genética , Salmo salar/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Gatos , Clonagem Molecular , DNA Complementar , Éxons , Duplicação Gênica , Genes de Imunoglobulinas , Humanos , Ictaluridae/genética , Ictaluridae/imunologia , Imunoglobulina D/classificação , Cadeias Pesadas de Imunoglobulinas/classificação , Cadeias Pesadas de Imunoglobulinas/genética , Isotipos de Imunoglobulinas , Cadeias mu de Imunoglobulina/genética , Camundongos , Dados de Sequência Molecular , Filogenia , Splicing de RNA , Salmo salar/imunologia , Homologia de Sequência de Aminoácidos
7.
J Virol ; 73(3): 2136-42, 1999 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9971796

RESUMO

The infectious salmon anemia virus (ISAV) is an orthomyxovirus-like virus infecting teleosts. The disease caused by this virus has had major economic consequences for the Atlantic salmon farming industry in Norway, Canada, and Scotland. In this work, we report the cloning and sequencing of an ISAV-specific cDNA comprising 2,245 bp with an open reading frame coding for a predicted protein with a calculated molecular weight of 80.5 kDa. The putative protein sequence shows the core polymerase motifs characteristic of all viral RNA-dependent RNA polymerases. Comparison of the conserved motifs with the corresponding regions of other segmented negative-stranded RNA viruses shows a closer relationship with members of the Orthomyxoviridae than with viruses in other families. The putative ISAV polymerase protein (PB1) has a length of 708 amino acids, a charge of +22 at neutral pH, and a pI of 9.9, which are consistent with the properties of the PB1 proteins of other members of the family. Calculations of the distances between the different PB1 proteins indicate that the ISAV is distantly related to the other members of the family but more closely related to the influenza viruses than to the Thogoto viruses. Based on these and previously published results, we propose that the ISAV comprises a new, fifth genus in the Orthomyxoviridae.


Assuntos
Anemia/veterinária , Doenças dos Peixes/virologia , Orthomyxoviridae/classificação , RNA Polimerase Dependente de RNA/química , Salmão/virologia , Sequência de Aminoácidos , Anemia/virologia , Animais , Clonagem Molecular , Sequência Conservada , Dados de Sequência Molecular , RNA Polimerase Dependente de RNA/genética
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