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Dosing cattle feed with harmless bacteria eliminates the dangerous E.
coli O157:H7 strain from their intestines, says an American team. Tens of
thousands of people fall ill every year through O157:H7 infections from cattle
manure or beef. Michael Doyle of the University of Georgia and his team isolated
strains of E. coli that produce antimicrobial agents that kill O157.
When these bugs were sprayed onto feed, they eliminated O157 from 80 to 90 per
cent of the cattle. 鈥淚n most animals, friendly E. coli will outcompete
O157 in two weeks,鈥� Doyle says.