394-19 Deactivation of Pathogenic Escherichia Coli O157:H7 In Dairy Manure Through Modification of pH and Temperature.



Wednesday, October 19, 2011
Henry Gonzalez Convention Center, Hall C, Street Level

John D. Toth1, Zhengxia Dou1, Shelley Rankin1, Helen Aceto1, Jesse Vanderhoef1 and Chitrita Debroy2, (1)Clinical Studies, University of Pennsylvania School of Veterinary Medicine, Kennett Square, PA
(2)E. coli Reference Center, Penn State University, University Park, PA
The enteric pathogenic bacteria E. coli O157:H7 is widely present in food animal production farms, and can pose a serious threat to human health if the pathogen moves off-farm and into the food production system.  To extend our previously-reported studies on control of Salmonella enterica serovar Newport in the dairy farm environment, we inoculated E. coli O157:H7 labeled with green fluorescence protein (gfp) into dairy manure and adjusted the pH in the range 4 to 5 with aluminum sulfate or to pH 10 to 12 with hydrated lime, and followed the deactivation kinetics of the pathogen over time through plating on sorbitol-MacConkey differential agar.  Similar to Salmonella, at pH between 4 to 5 and 10 to 11, pathogen concentrations in the manure demonstrated a transient decline by up to 100-fold before increasing again.  E. coli O157:H7 had relatively low survivability in manure; in most treatments it was not found beyond 14 days.  E. coli survival characteristics in manure incubated at 4, 22 or 37 degrees C will be discussed.
See more from this Division: S11 Soils & Environmental Quality
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