Language selection


Management of coldwater disease caused by Flavobacterium psychrophilum on Ontario trout farms: erythromycin efficacy and family susceptibility



Bacterial coldwater disease (BCWD) caused by Flavobacterium psychrophilum is the most important production-limiting disease for Ontario Rainbow Trout farmers. Disease occurs following stresses, such as handling and transfers, and is always a risk at water temperatures below 12-13 ℃. There is no commercial vaccine for BCWD and fish veterinarians have a limited repertoire of microbials to manage disease outbreaks. The goal of this project is to develop new prophylactic and therapeutic approaches to minimise the potential onset of resistant F. psychrophilum strains in Ontario trout. This will be achieved by monitoring trends in susceptibility of F. psychrophilum strains from various farms to existing antimicrobials, testing the on-farm use of an alternative antimicrobial and determining breakpoints for several antimicrobials. Progeny from families of Rainbow Trout that are selected for growth and other production parameters will be assessed for susceptibility to F. psychrophilum. This may allow preferential selection of families that both grow faster, etc. but are also less likely to suffer from BCWD. This work will directly advance the Ontario aquaculture sector by providing tools to reduce antimicrobial use in food animals and the clinical and economic impact of a major production-limiting disease.

Program Name

Aquaculture Collaborative Research and Development Program (ACRDP)


2010 - 2011


Central Canada: Great Lakes, St. Lawrence Freshwater Drainage Basin

Principal Investigator(s)

Doug Geiling

Date modified: