Biotyping of Salmonella typhimurium strains isolated from animals and birds in northern Japan.

Strains of Salmonella typhimurium (n = 175) isolated from animals and birds in northern Japan were differentiated into 5 biovars (1, 2, 7, 10, and untypeable) by 6 kinds of fermentation tests (inositol, bitter-xylose, rhamnose, xylose, Stern's glycerol, and trehalose) of Brandis' scheme, and were subdivided into 9 primary and 38 full biovars by a new biotyping method, using additional biochemical reactions. The full biovar classified by the new biotyping method was considered to be a marker for assessing the widespread outbreaks of infection with S typhimurium. In particular, strains of biovars 25hi and 27hi were characteristically found in pigeons, quail, and fantails, and were thought to be of avian origin.