Factors affecting the efficacy of an oral vaccine against a Canadian isolate of Piscirickettsia salmonis

Description

Salmonid rickettsial septicemia (SRS) is a disease of farmed salmonids (salmon, trout, and charr) caused by infection with the bacterium Piscirickettsia salmonis. In British Columbia (BC), SRS mainly occurs in areas with warmer sea temperatures (such as the west coast of Vancouver Island) during the warmer months (July to September). The distribution and severity of SRS have recently increased, in association with trends towards warmer winters.

In Chile, SRS is the most frequently diagnosed pathogen in salmonids reared in seawater. To address this, more than 25 commercial SRS vaccines are available to the Chilean aquaculture industry. In Canada, there is currently no commercial vaccine with proven efficacy against SRS. It is unknown whether the commercial SRS vaccines available in Chile would protect salmonids against P. salmonis bacteria sampled from Canadian locations (Canadian “isolates”).

The main goal of this project is to analyze how well a commercial SRS vaccine from Chile performs when administered to Atlantic Salmon exposed to a BC isolate of P. salmonis. The project will determine the response of Atlantic Salmon given a single vaccination and those given a second booster vaccination and the frequency of infection in the vaccinated fish. The project aims to demonstrate the effect of booster vaccination on the efficacy of the commercial vaccine against SRS. New knowledge about the usefulness of vaccination as a tool to manage SRS could lead to mitigation or prevention of this disease in the Canadian finfish aquaculture industry.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)

Year(s)

2020-2021

Principal investigator

Simon Jones, Research Scientist, Fisheries and Oceans Canada, Pacific Biological Station, Pacific Region

Email: Simon.Jones@dfo-mpo.gc.ca

Team member(s)

Amy Long, Research Scientist, Department of Fisheries and Oceans, Pacific Biological Station, Pacific Region

Øyvind Brevik, Senior Researcher, Cermaq

Jaime Tobar, Biological R&D Manager, Centrovet, Chile

Collaborator(s)

Kathleen Frisch, Fish Health Director, Cermaq Canada Ltd.

Henrik Duesund, Fish Health R&D Manager, Cermaq Group AS

Jaime Tobar, Biological R&D Manager, Centrovet Ltd.