Genetically engineered monoclonal antibody for E coli diarrhea in calves.

A genetically engineered monoclonal antibody, given PO to calves within 12 hours of birth, reduced the severity of diarrhea caused by enterotoxigenic K99 E coli. In challenge studies, dehydration and deaths were markedly reduced in treated calves vs untreated controls (29% vs 82%, 28% vs 82%). Use of the antibody in double-blind field trials on dairy calves in 9 herds in 5 states markedly reduced the severity of E coli diarrhea.