Research of acute phase proteins followed after Streptococcus iniae-infected in tilapia (Oreochromis niloticus)

Streptococcus iniae is an important bacterial pathogen of fish, causing up to 50%mortality in stocks, which has recently been associated with human infections. The aim ofthe present study to assess C-reactive protein, fibrinogen, serum amyloid A and transferrinresponses to Streptococcus iniae (ATCC 29178) in plasma of tilapia (Oreochromis niloticus,Linnaeus 1758) following intraperitoneal (i.p.) injection. Two experiment groups, includingS.iniae-infected (st group) and S.iniae-infected with handling stress (st-hd group), with agroup of nonstressed control (cntrl) fish, were examined in this study. Blood samples werecollected 7th , 14th and 21st days after the experiment. In our study, darken skin, slowdownand confusion in fish motions in infected groups within 1-2 days. Only fibrinogen levelsfrom measured acute phase proteins has been reported to decrease.Key Words: Tilapia, C-reactive protein, Serum amyloid A, Fibrinogen, Transferrin