Susceptibility of Sockeye salmon to viral hemorrhagic septicemia virus

Description

As part of the sustainable management of finfish aquaculture, there are regulatory requirements that are designed to minimize the transfer of pathogens from farmed finfish to wild fish. However, finfish cultured in ocean net pens have the potential to be exposed to naturally occurring pathogens and to transfer pathogens to wild fish. Viral hemorrhagic septicemia virus (VHSV) has been identified in farmed Atlantic salmon, Salmo salar, in British Columbia. VHSV is a naturally occurring pathogen in British Columbia and is a cause of serious disease in wild Pacific herring, Clupea pallasii. Pacific herring are known to enter and remain in Atlantic salmon net pens, thereby increasing the potential for the virus to be transferred to farmed Atlantic salmon. Although the occurrence of VHSV in farmed salmon is rarely accompanied with significant disease and mortality, experimental studies have shown that the VHS virus can persist in the tissue of farmed Atlantic salmon. This causes concern for potential host adaptation and viral spillback to fish sharing the marine environment.

This study is investigating what effect, if any, the occurrence of VHSV in farmed Atlantic salmon may have on wild Sockeye salmon. Previous studies have shown that Coho, Chinook, and Chum salmon are natural hosts of VHSV, but less is known about the susceptibility of Sockeye salmon to VHSV. To address this knowledge gap, this project will determine the susceptibility of Sockeye salmon smolts to VHSV using laboratory exposure studies. The results of this study will contribute to the development of adaptive management strategies in British Columbia aimed at minimizing the transfer of pathogens between farmed Atlantic salmon and wild Pacific salmon.

Findings

N/A

Publications

N/A

Program Name

Program for Aquaculture Regulatory Research (PARR)

Year(s)

2015 - 2017

Ecoregion(s)

Pacific: North Coast and Hecate Strait

Principal Investigator(s)

Kyle Garver
Research Scientist, Pacific Biological Station
3190 Hammond Bay Rd., Nanaimo, British Columbia
Email: Kyle.Garver@dfo-mpo.gc.ca

Team Member(s)

Paul Hershberger

Jon Richard