Oomycete infections in farmed fish are one of the most significant disease issues in salmonid aquaculture worldwide. In the present study, Saprolegnia spp. in different farmed fish species in Finland were identified, and the molecular epidemiology of especially Saprolegnia parasitica was examined. We analysed tissue samples from suspected oomycete‐infected salmonids of different life stages from a number of fish farms, as well...

Flavobacteria are among the most important pathogens in freshwater salmonid aquaculture worldwide. Due to concerns regarding development of antibiotic resistance, phage therapy has been proposed as a solution to decrease pathogen load. However, application of phages is challenged by the development of phage resistance, and knowledge of the mechanisms and implications of phage resistance is therefore required. To study this, 27...

Summary The fish pathogen Flavobacterium psychrophilum infects farmed salmonids worldwide, and application of bacteriophages has been suggested for controlling disease outbreaks in aquaculture. Successful application of phages requires detailed knowledge about the variability in phage susceptibility of the host communities. In this study, we analysed the genetic diversity of F. psychrophilum hosts and phages from the Baltic Se...