猪源链球菌溶血性的检测

用平板法和上清法检测了19株猪源链球菌的溶血性，并通过加入还原剂或氧化剂分别作活化和抑制试验，对各菌株溶血素的性质做了初步鉴定，其中8株猪链球菌2型菌株在血平板上的溶血性较弱，仅为α溶血或弱β溶血，但在THB和5%血清THB中都可产生很强的溶血性，其溶血性可被还原剂活化，被氧化剂和胆固醇所抑制，卵磷脂对其活性则没有影响，属于巯基活化类（类SLO）溶血素，9株马链球菌兽疫亚种菌株在血平板上呈显的β溶血，在不含血清THB中不能产生溶血性，在含血清的THB中可产生较强的溶血性，其活性不被还原剂活化，不被氧化剂抑制，胆固醇能抑制大部分活性，卵磷脂则可全部抑制，属于类SLS溶血素，两株非典型兰氏C群链球菌菌株在血平板上呈显的β溶血，在THB中显示了非常强的溶血性，其活性不被还原剂活化，不被氧化剂抑制或卵磷脂抑制，但被胆固醇强烈抑制，属于非SLO，非SLS溶血素。

HEMOLYSIN EXAMINATION OF SWINE STREPTOCOCCAL ISOLATES

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.