HEMOLYSIN EXAMINATION OF SWINE STREPTOCOCCAL ISOLATES / 微生物学通报

ABSTRACT

The hemolysin production of 19 strains of Streptococcus spp. isolated from pigs in the Jiangsu and Shanghai regions in recent years were examined. Eight isolates of Streptococcus suis type 2 from Jiangsu showed weak hemolysis on blood agar, but a stronger reaction in Todd-Hewitt broth(THB). The hemolysin belonged to the group of thiol-activated hemolysins. Nine strains of Streptoccus equi subsp. zooepidemicus showed strong hemolysis on blood agar and in THB containing 5% new-born calf serum, but no hemolysis in THB alone. This hemolysin was similar to streptolysin S(SLS). Another two isolates were atypical members of Lancefield group C Streptococcus and showed strong hemolysis on blood agar and in THB with 5% new-born calf serum, but the hemolysin was unlike either streptolysin O or SLS.