Determination of the Protective Effect of IHNV Plaque Neutralizing Antibody Titres (PNT) when Passively Transferred to Naïve Atlantic Salmon

Description

Infectious hematopoietic necrosis virus (IHNV), the causative agent of IHN, is endemic to the western coast of North America. IHNV is the most economically important viral disease of salmonids. In British Columbia the virus is most often detected in sockeye salmon (Onchorhynchus nerka) where high losses have been reported in young fish in rivers and spawning channels (Williams and Amend, 1976, Traxler and Rankin, 1989). While many species of Pacific salmon are refractory to IHNV infection in the marine environment (Traxler et al., 1997), IHNV is highly infective, pathogenic and virulent in Atlantic salmon (Traxler et al., 1998). Atlantic salmon were introduced into British Columbia for aquaculture purposes in the mid-1980's and IHN was diagnosed in a marine net-pen in 1992 (Armstrong et al. 1993; Traxler et al., 1993). There have been two serious outbreaks of infectious hematopoietic necrosis (IHN) in farmed Atlantic salmon in British Columbia: 1992-1996 and 2001-2003 (St-Hilaire, 2000; Saksida, 2004). During the latest epizootic, mortalities were greater than 70% in fish less than 1 kg and averaged 40-50% when fish were larger than 1 kg. Thirty-six farm sites were diagnosed with IHNV during this epizootic (Saksida, 2004). The estimated economic loss resulting from both epizootics was $40 million in inventory representing $200 million in lost sales.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)

Year(s)

2005 - 2007

Ecoregion(s)

Pacific: Vancouver Island West Coast

Principal Investigator(s)

Garth Traxler
Email: TraxlerG@pac.dfo-mpo.gc.ca