The incidence of Lactococcosis caused by Lactococcus garvieae, in rainbow trout (Oncorhynchus mykiss, Walbaum, 1792) farms is disquieting and increasing in recent years. Knowledge of biotypes and serotypes involved in disease incidence is essential to adopt disease prevention and control policies. Twelve isolates of L. garvieae from some rainbow trout farms were identified by phenotypic, bioche...