Biotyping and colicine typing of Salmonella typhimurium strains of phage type 141 isolated in Scotland.

Cultures of Salmonella typhimurium (551 strains) of phage type 141 isolated in Scotland from 1965 to 1977 were examined for biotype and colicine type. Three main biotype clones were recognised: If (30 strains), 9f (507 strains) and 31bd (11 strains) with subtype variants 9bf (1 strain), 9cf (1 strain) and 31b (1 strain). The contribution made by each biotype clone to outbreaks in Scotland was analysed. The findings confirmed the distinctness of the three biotype clones within the single phage type and indicated possible origins of strains of biotypes of 9f and 31bd.