Identification and characterization of Streptococcus suis

A total of 188 Streptococcus suis strains isolated from pigs with various lesions mainly bronchopneumonia, were identified using classical biochemical methods and using the API 20 STREP system. The serological classification was performed by precipitation reactions after Lancefield extraction, slide-coagglutinations and capsular reaction tests. Fifty-nine strains belonged to Types 1, 1 2 or 2, 78 strains to Types 3–8 and 51 strains were non-typable. The results of the different tests and the biochemical differences between the different serotypes are discussed.