Fifteen strains of Escherichia coli which had been collected in previous studies from animals and meat were studied.
They belonged to serotypes considered enterotoxigenic and were examined for the production of the heat-labile and heat-stable enterotoxins. Only one of these strains (O8. Hnt) isolated from a Cheshire produced heat-labile enterotoxin. Another strain (O8.H9) isolated from a cowpat in another part of Cheshire gave results suggesting production of small amounts of the heat-stable enterotoxin. The ecological aspects of these results are discussed.