Verotoxin production among porcine strains of Escherichia coli and its association with oedema disease

Abstract
Summary Strains of Escherichia coli isolated from documented cases of disease in pigs and belonging to a wide range of pathogenic serotypes were tested for their ability to produce a heat labile verotoxin (VT). The strains isolated from oedema disease all produced VT, indicating that the cytotoxin detected by the vero-cell assay was identical to “oedema disease principle”. Strains belonging to the serotypes associated with enterotoxic diarrhoea were VT−. Not all the strains belonging to the recognised oedema disease serotypes (O141:K85, O139:K82 and 0138.K81) produced VT, but the VT− strains were not associated with outbreaks of clinical disease.