A set of 451 and 115 strains of Escherichia coli isolated from piglets and
calves affected by diarrhoea, respectively, were tested for verotoxin produ
ction and type. The production was tested on Vero cells and the type was id
entified by PCR. The production of verotoxin was demonstrated in 189 of the
porcine strains and 13 of the bovine strains. Most of the porcine verotoxi
genic strains belonged to the serogroups O139, O141, O157, and O138. Positi
ve for verotoxin production were 83.3% and 78.2% of the strains of the sero
groups O139 and O141, respectively. The type VT2e was identified in 184 str
ains and a sequence corresponding to VT2c was found in 2 strains. However,
the latter yielded negative results in the Vero cells test. Furthermore an
unidentified toxin type was demonstrated in three strains positive in the V
ero cell culture. The bovine verotoxigenic strains belonged to the serogrou
ps O20, O26, O103, O111, and O157. Both VT1 and VT2 were produced by 6 (46.
2%) of the 13 verotoxigenic strains. Only one verotoxin type was produced b
y each of the remaining verotoxigenic strains.