LAUSR

Abstract Mass mortality in cultured common carp from a farm of Ganyu county, Jiangsu province, P. R. China was reported. The two dominated isolates named L1 and L2 from diseased common carps were confirmed as non-O1 Vibrio cholerae by biochemical characteristics and molecular tools. Virulence genes (ompW, hlyA, acfA, toxR, ace and rtxC genes) were found to be present in the isolates by PCR, which further confirmed pathogenicity of the isolates. The LD50 value of the isolate L1 to the common carp was 1.1 × 106 CFU/mL. In addition, the specific egg yolk powder (IgY) conferred significant protection of common carp against non-O1 V. cholerae. The specific IgY also exhibited significant bacteriolytic effects on the non-O1 V. cholerae pathogen. The results showed that the specific IgY should be an effective implemented feed additive for the biocontrol of non-O1 V. cholerae infection in aquaculture.