Identification of encountered bacterial pathogens related with streptococcosis cases by using multiplex polymerase chain reaction (MPCR) in trout

For this research a number of 220, weighing in 50-60 g rainbow trout (Oncorhynchus mykiss Walbaum 1792) samples from 4 different fish farm were examined by multiplex PCR (mPCR). At the end of multiplex PCR study, Streptococcus spp. and Lactococcus spp. target pathogens were identified at the rate of 62.71% from whole samples. The percentage distribution according to identified species were at the rate of L. garvieae 52.17%, S. parauberis 27.54% and S. difficilis 20.29%. The identified target pathogens by multiplex PCR percentage distribution according to fish farms, L. garvieae was isolated at the highest rate of 45.45% from 1st fish farm. In general fish farm evaluations (1st, 2nd, 3rd, 4th) showed that performed isolations were at the rate of 38.41%; 25.36%; 16.67% and 19.56%, respectively. In our study, Lactococcus garvieae, Streptococcus parauberis and Streptococcus difficilis presences in rainbow trout (Oncorhynchus mykiss Walbaum 1792) were determined by multiplex PCR. Streptococcus ineae; the main agent of streptococcosis which causes economic losses with mortality in rainbow trout (Oncorhynchus mykiss Walbaum 1792) was not identified. Moreover, Lactcoccus garvieae, Streptococcus parauberis and Streptococcus difficilis were found out by multiplex PCR which are main pothogens in streptococcosis. Keywords: S. difficilis, S. parauberis, L. arvieae, S. iniae, rainbow trout, identification, mPCR.