Additive protective effects of colostral antipili antibodies in calves experimentally infected with enterotoxigenic Escherichia coli.

With oral infection of calves by an enterotoxigenic Escherichia coli strain carrying K99, F41, and FY adhesins, colostrums from cows vaccinated against either K99+F41 or FY did not provide protection, but a mixture of the two colostrums did. The association of antibodies directed against the different adhesins is more effective than antibodies directed against one adhesin alone for colostral protection against enterotoxigenic E. coli carrying several adhesins.