Disease caused by Yersinia ruckeri serotype O2b found in Chilean-farmed coho salmon, Oncorhynchus kisutch (Walbaum, 1792)

Abstract

During September and October 2015, farmed coho salmon (Oncorhynchus kisutch [Walbaum, 1792]) suffered outbreak mortalities. For all outbreaks, cumulative losses of the affected population reached up to 15%. Three representative bacterial isolates were recovered with the objective of antigenically identifying and characterizing the causative microorganism of the ERM outbreaks in Chilean coho salmon. The obtained micro-organisms were characterized as Y. ruckeri O2b, making this the first report of a mortality-associated isolate in coho salmon farmed in Chile.