Escherichia coli isolated from farm animals in England and Wales between 1986 and 1991

Abstract

Escherichia coli isolated from farm animals in England and Wales between 1986 and 1991 were examined for their serogroup, fimbrial adhesin and toxin production, and resistance to antimicrobial drugs. Among the 3595 porcine isolates the more common serogroups were O149, O8, O138, O147 and O157. The F4(K88) adhesin was detected in 21 per cent of the cultures, whereas the other adhesins were never present in more than 3 per cent during any year, although there was an upward trend in the prevalence of the F6(987P) antigen. The heat labile enterotoxin was produced by more than 17 per cent of the cultures usually in association with the F4 antigen. The other toxins, heat stable (STa), verocytotoxin (VT) and cytotoxic necrotising factor (CNF) were produced by 5.3, 4.7 and 6.8 per cent of the cultures, respectively. Among the 1383 bovine cultures the more common serogroups were O8, O101 and O17. The F5(K99) adhesin was detected in 9.1 per cent of the cultures, usually in association with STa production. The toxins STa, VT and CNF were produced by 4.4, 2.8 and 8.3 per cent of the cultures, respectively. Among the 407 ovine isolates the more common serogroups were O8, O101 and O78, and 11 per cent of the cultures produced the F5(K99) antigen. The toxins STa, VT and CNF were produced by 1.5, 6.1 and 9.1 per cent of the cultures, respectively. In the case of the 402 poultry isolates the more common serogroups were O78, O2 and O8, which are usually associated with colisepticaemia. Resistance to antibiotics was common, particularly among the bovine isolates.