Main content area

Systemic infection in European perch with thermoadapted virulent Aeromonas salmonicida (Perca fluviatilis)

Rupp, Melanie, Pilo, Paola, Müller, Barbara, Knüsel, Ralph, von Siebenthal, Beat, Frey, Joachim, Sindilariu, Paul‐Daniel, Schmidt‐Posthaus, Heike
Journal of fish diseases 2019 v.42 no.5 pp. 685-691
Aeromonas salmonicida, Cyprinidae, Lepomis macrochirus, Perca fluviatilis, cold-water fish, furunculosis, genes, perch, plasmids, recirculating aquaculture systems, temperature, toxicity testing, type III secretion system, virulence
In non‐salmonid fish, Aeromonas salmonicidacan cause local infections with severe skin ulcerations, known as atypical furunculosis. In this study, we present a systemic infection by a virulent A. salmonicidain European perch (Perca fluviatilis).This infection was diagnosed in a Swiss warm water recirculation aquaculture system. The isolate of A. salmonicida encodes a type three secretion system (TTSS) most likely located on a plasmid similar to pAsa5/pASvirA, which is known to specify one of the main virulence attributes of the species A. salmonicida. However, the genes specifying the TTSS of the perch isolate show a higher temperature tolerance than strains isolated from cold‐water fish. The function of the TTSS in virulence was verified in a cytotoxicity test using bluegill fry and epithelioma papulosum cyprinid cells.