Characterization of Aeromonas hydrophila isolated from diseased fish and the potential of sodium alginate as a carrier for oral vaccine

Abstract

Bacterial diseases in aquaculture are considered to be a major cause of fish mortalities. Disease due to Aeromonas hydrophila is one of the most common bacterial diseases in aquaculture. This bacterium causes hemorrhagic septicaemia, abdominal dropsy and ulcers. Effective prevention is necessary to overcome the outbreak of bacterial disease. Thus this study was conducted to isolate, identify and characterize A. hydrophila from diseased fish. The virulence and pathogenicity of the isolates were evaluated for vaccine candidate selection. The in vitro suitability of sodium alginate as coating agent for oral formalin killed A. hydrophila vaccine was evaluated. A. hydrophila were isolated, identified and characterized using conventional biochemical tests. Two representative isolates were subjected to 16S rRNA gene sequencing and analysed for identity confirmation.