Grain feeding and the dissemination of acid-resistant Escherichia coli from cattle

Science. 1998 Sep 11;281(5383):1666-8. doi: 10.1126/science.281.5383.1666.


The gastric stomach of humans is a barrier to food-borne pathogens, but Escherichia coli can survive at pH 2.0 if it is grown under mildly acidic conditions. Cattle are a natural reservoir for pathogenic E. coli, and cattle fed mostly grain had lower colonic pH and more acid-resistant E. coli than cattle fed only hay. On the basis of numbers and survival after acid shock, cattle that were fed grain had 10(6)-fold more acid-resistant E. coli than cattle fed hay, but a brief period of hay feeding decreased the acid-resistant count substantially.

MeSH terms

  • Animal Feed*
  • Animal Husbandry
  • Animals
  • Bacteria, Anaerobic / growth & development
  • Cattle / microbiology*
  • Colon / chemistry
  • Colon / microbiology*
  • Colony Count, Microbial
  • Culture Media
  • Diet
  • Edible Grain*
  • Escherichia coli / growth & development*
  • Fatty Acids, Volatile / analysis
  • Hydrogen-Ion Concentration
  • Lactic Acid / analysis
  • Poaceae*
  • Random Allocation
  • Rumen / chemistry
  • Rumen / microbiology
  • Succinates / analysis


  • Culture Media
  • Fatty Acids, Volatile
  • Succinates
  • Lactic Acid