Genomic characterization of jaundice-associated mortality events in cultured Chinook Salmon?

Description

Over the past seven years mortalities of Chinook Salmon farmed in Tofino inlet have been observed with unique clinical presentation. The salmon present with mild to severe yellow discoloration of the skin (jaundice) and very pale gills, indicating anemia. Histological examination has found severe liver and kidney damage (renal tubular necrosis and hydropic degeneration). Possible etiologies include a viral pathogen and/or exposure to a negative environmental influence. In order to differentiate between these two etiologies, we are using a genomic approach to characterize fish with the jaundice syndrome using:

1. salmonid microarrays performed on liver tissues,
2. quantitative RT-PCR (Reverse Transcription - Polymerase Chain Reaction) biomarkers to osmoregulatory genes in gill tissue, and
3. TaqMan assays targeting a wide range of salmon pathogens identified throughout the world. Epidemiology and histopathology analyses are also being conducted.

The specific experimental focus is on fish from two farm sites collected over the winter of 2011 from pens with and without jaundice outbreaks. The goal of this research is to understand better the epidemiology and etiology of this jaundice syndrome so that tools and strategies can be developed for mitigation.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)

Year(s)

2011 - 2012

Ecoregion(s)

Pacific: Vancouver Island West Coast

Principal Investigator(s)

Kristi Miller
Email: MillerK@pac.dfo-mpo.gc.ca