An examination of Escherichia coli strains isolated from cases of bovine mastitis for possible virulence determinants

Ninety-five strains of Escherichia coli isolated from cases of bovine mastitis were examined for the possession of some of the possible virulence determinants. Ten strains which caused haemagglutination of bovine and ovine erythrocytes were considered to be fimbriated and an additional strain caused agglutination of chicken erythrocytes. Colicines were produced by fifteen strains and in three strains the colicine was identified as Col V. Forty-one of 71 strains that were examined serologically possessed capsular or envelope K antigens.