Infectious haematopoietic necrosis virus (IHNV) is one of the most important viral pathogens of salmonids. In rainbow trout, IHNV isolates in the M genogroup are highly pathogenic, while U genogroup isolates are significantly less pathogenic. We show here that, at a multiplicity of infection (MOI) of 1, a representative U type strain yielded 42-fold less infectious virus than an M type strain i...

Infectious hematopoietic necrosis virus (IHNV) is a negative-sense RNA virus that infects wild and cultured salmonids throughout the Pacific Coastal United States and Canada, from California to Alaska. Although infection of adult fish is usually asymptomatic, juvenile infections can result in high mortality events that impact salmon hatchery programs and commercial aquaculture. We used epidemio...

Multiple virus infections have recently been observed during routine examination of salmonid fish.1) Infectious hematopoietic necrosis virus (IHNV) and infectious pan creatic necrosis virus (IPNV) are often isolated together or with other viruses, such as a herpes virus or a retro-like virus.1,2) In case of multiple virus infections, only the virus which replicates most efficiently will be dete...

To further enhance our understanding of immunological gene expression in rainbow trout, Oncorhynchus mykiss, after infection with naturally occurring pathogens, a series of probes and primers were developed for the quantification of immune factors. Separate groups of specific-pathogen-free rainbow trout were infected with either Flavobacterium psychrophilum, Aeromonas salmonicida or infectious ...

Seven rainbow trout cytokine genes (interleukin (IL)-2, IL-8, IL-15, IL-17, IL-1β, intracellular interferon (iIFN) 1a, and IFN-γ2) were evaluated for their adjuvant effects on a DNA vaccine, called pG, containing the glycoprotein gene of infectious hematopoietic necrosis virus (IHNV). Distinct DNA constructs in expression plasmid pcDNA3.1 encoding a cytokine gene were generated. Immunofluoresce...

The mRNA transcribed from the N gene of viral haemorrhagic septicaemia virus (VHSV) of salmonids has been cloned in Escherichia coli and expressed. Fusion proteins were recognized by monoclonal antibody directed against the N protein from the viral particle. A 1212 bp long open reading frame (ORF) coding for 404 amino acids with a calculated Mr of 44590 was deduced from the nucleotide sequence....

We have developed a novel in vivo superinfection fitness assay to examine superinfection dynamics and the role of virulence in superinfection fitness. This assay involves controlled, sequential infections of a natural vertebrate host, Oncorhynchus mykiss (rainbow trout), with variants of a coevolved viral pathogen, infectious hematopoietic necrosis virus (IHNV). Intervals between infections ran...

BPA project number: 20056 Contract renewal date (mm/yyyy): Multiple actions? Business name of agency, institution or organization requesting funding Business acronym (if appropriate) USGS-WFRC Short description RNase protection technology will be used to survey the genetic types of IHN virus throughout the Columbia Basin, to identify sources of disease outbreaks, and to infer viral traffic patt...