Isolation and identification of Vibrio toranzoniae associated with diseased red conger eel (Genypterus chilensis) farmed in Chile

- First isolation of Vibrio toranzoniae from cultured red conger eel is reported.
- Identification of isolates was performed by a polyphasic taxonomic approach.
- Inoculation in turbot demonstrated the pathogenic potential of the isolates.
- Results indicate a wide geographical and host distribution of V. toranzoniae.

The present study deals with the first isolation of Vibrio toranzoniae from cultured red conger eel (Genypterus chilensis). During the summer season of 2011, mortalities were observed in young red conger eel at one aquaculture experimental rearing system in Quintay, Valparaiso, Chile. The microbiological analysis of the diseased fish resulted in the isolation of three dominant and representative isolates, designated as R.17, R.18 and R.19, which were obtained from gill, fin and external lesions from three different fish, respectively. All isolates were identified as V. toranzoniae by means of a polyphasic taxonomic approach, including phenotypic characterization, sequencing of 16S rRNA and housekeeping genes, and DNA-DNA hybridization. Inoculation of a representative strain (R18) in turbot as model fish species demonstrated the pathogenic potential for fish of the Chilean isolates. Results obtained indicate that the geographical and host distribution of V. toranzoniae is wider than expected, and that this species may have negative incidence in the culture of marine organisms.