TOXIGENIC ESCHERICHIA-COLI IN SPANISH PIGGERIES FROM 1986 TO 1991

Four-hundred and fourteen faecal samples from pigs with diarrhoea, oed ema disease or healthy pigs, were collected from 65 piggeries located in different areas of Spain from 1986 to 1991. A total of 1334 Escheri chia coli cultures were isolated from the pigs and studied for product ion of heat-labile (LT) and heat-stable (STa) enterotoxins, verotoxin (VT) and for type 1 (CNF1) and type 2 (CNF2) cytotoxic necrotizing fac tors. Strains producing enterotoxins (P<0.001) or verotoxin (P<0.05) w ere associated with enteric diseases of pigs. In the majority (82.3%) of piglets with strains, producing verotoxin the strains were also pos itive for production of STa enterotoxin. The most frequent toxin detec ted was STa. Although we isolated strains producing CNF1 from 1.5% of sick pigs, they were not statistically associated (P<0.7) with enteric disease. Pigs may constitute a natural reservoir of CNF1 producing E. coli strains in Spain; their presence in the porcine intestine may be of significance in public health because such strains have been assoc iated with human extraintestinal infections.