IMPROVEMENT OF RFLP-BASED IDENTIFICATION OF LACTIC ACID BACTERIA ISOLATED FROM HEALTHY AND DISEASED FISH: DIFFERENTIAL DIAGNOSIS AND PRACTICAL ISSUES

摘要

Gram-positive lactic bacteria have become a major source of concern for aquaculture in the last decades. Aside true pathogenic species of worldwide significance, like Streptococcus iniae and Lactococcus garvieae, several species have been reported toproduce occasional fish mortalities in limited geographic areas. From laboratory diagnostic practice it appears, in fact, that lactic acid bacteria are much more commonly associated to fish and fish products than it was formerly believed, and that repeated isolation of unidentifiable or ill-defined isolates may sometimes be confusing.