Catfish columnaris disease cases dominated by one genetic type of Flavobacterium columnare

Authors: Lafrentz, Benjamin

Submitted to: Fish Farming News
Publication Type: Popular Publication
Publication Acceptance Date: 10/28/2021
Publication Date: 11/4/2021
Citation: Lafrentz, B.R. 2021. Catfish columnaris disease cases dominated by one genetic type of Flavobacterium columnare. Fish Farming News. 2021(2):9.

Interpretive Summary: Columnaris disease, caused by the bacterial pathogen Flavobacterium columnare, continues be the second leading cause of disease related mortality in the catfish industry. Our research revealed that there are four different types of F. columnare. Historically, three of these types have been found to be associated with disease in the catfish industry; however, the type currently impacting the industry is not known. We pioneered genetic tools to rapidly assign an unknown F. columnare strain to one of the four types. These tools were used to determine the type(s) of F. columnare impacting the industry by investigation of 260 columnaris disease cases in Alabama and Mississippi. The results confirmed the historical records that three types are present but demonstrate that genetic group 2 F. columnare dominates columnaris disease cases in the catfish industry (94% of cases were assigned to type 2 F. columnare). Our current research is using this new knowledge to develop vaccines and other prevention and control strategies for the catfish industry by focusing on type 2 F. columnare.

Technical Abstract: Columnaris disease, caused by the bacterial pathogen Flavobacterium columnare, continues be the second leading cause of disease related mortality in the catfish industry. Our research revealed that there are four different types of F. columnare. Historically, three of these types have been found to be associated with disease in the catfish industry; however, the type currently impacting the industry is not known. We pioneered genetic tools to rapidly assign an unknown F. columnare strain to one of the four types. These tools were used to determine the type(s) of F. columnare impacting the industry by investigation of 260 columnaris disease cases in Alabama and Mississippi. The results confirmed the historical records that three types are present but demonstrate that genetic group 2 F. columnare dominates columnaris disease cases in the catfish industry (94% of cases were assigned to type 2 F. columnare). Our current research is using this new knowledge to develop vaccines and other prevention and control strategies for the catfish industry by focusing on type 2 F. columnare.