Biochemical and serological analysis of Vibrio anguillarum related organisms

This work reports on the phenotypic and serological characterization of Vibrio anguillarum related (VAR) organisms isolated from diseased fish, shellfish, and from the environment in different geographical areas. Reference strains of V. a n g u ~ l l a r u m (serotypes 0 1 to 010) and V splendidus (biotype I ) were lncluded for comparison. On the basis of numerical taxonomy analysis the stralns were grouped in 4 phena, with similarity levels among them ranging from 77.6 to 86.8% and levels of internal similanty ranging from 84.1 to 86.8%. The serolog~cal analysis demonstrated that 22 of 45 (49%) VAR strains were typeable, being distributed into 7 0-serogroups (A, B, C, D, E, F, G). Six of these serogroups (A, B, C, D, F, and G) were recognized among 21 VAR strains isolated from diseased fish. Serotypes C and F were the predominant types among strains isolated from diseased turbot and cod, respectively. No dominating environmental serotype was found. Moreover, it was found that only serogroup F constituted a heterogeneous group with regard to phenotypic and serological characteristics.