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United States Department of Agriculture

Agricultural Research Service

Research Project: INTERVENTIONS TO REDUCE FOODBORNE PATHOGENS IN SWINE AND CATTLE

Location: Food and Feed Safety Research

Title: Impact of by-product feedstuffs in Escherichia coli O157:H7 and Salmonella Typhimurium in pure and mixed ruminal and fecal culture in vitro

Authors
item CALLAWAY, TODD
item Block, Stephanie -
item GENOVESE, KENNETH
item ANDERSON, ROBIN
item HARVEY, ROGER
item NISBET, DAVID

Submitted to: Agriculture, Food and Analytical Bacteriology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: March 24, 2012
Publication Date: October 23, 2012
Repository URL: http://handle.nal.usda.gov/10113/57236
Citation: Callaway, T.R., Block, S., Genovese, K.J., Anderson, R.C., Harvey, R.B., Nisbet, D.J. 2012. Impact of by-product feedstuffs in Escherichia coli O157:H7 and Salmonella Typhimurium in pure and mixed ruminal and fecal culture in vitro. Agriculture, Food and Analytical Bacteriology. 2:139-148.

Interpretive Summary: The use of by-product feedstuffs and prebiotics in animal rations has increased in recent years, but, in general, the effects of these by-products on the microbial ecosystem remain unknown. The present study was undertaken to determine what effects these novel feedstuffs, including prebiotics, have on survival of the important foodborne pathogenic bacteria Escherichia coli O157:H7 and Salmonella enterica Typhimurium in pure and mixed ruminal and fecal culture fermentations from cattle and swine. In general, the byproduct feedstuffs did not affect E. coli O157:H7 or Salmonella enterica populations, but prebiotic formulations that provided limiting nutrients to other members of the microbial population did reduce pathogen populations. This indirect effect has been previously reported for prebiotics and has potential for use to improve human food safety. Further research is needed to identify modes of action of these by-product feedstuffs and impacts they have on the mixed intestinal microbial ecosystem.

Technical Abstract: The use of by-product feedstuffs and prebiotics in animal rations has increased in recent years, but, in general, the effects of these by-products on the microbial ecosystem remain unknown. The present study was undertaken to determine what effects novel by-product feedstuffs, including prebiotics, have on survival of the important foodborne pathogenic bacteria Escherichia coli O157:H7 and Salmonella enterica Typhimurium in pure and mixed ruminal and fecal culture fermentations from cattle and swine. By-product feedstuffs utilized in this study included: hyperimmunized whole egg, lysine biomass, lysine biomass (spray-dried), threonine biomass (drum-dried), threonine biomass (spray-dried), beer well yeast (drum-dried), beer well yeast (spray-dried), ethanol yeast (pan-dried), and corn meal as a control to simulate normal dietary conditions. Prebiotics examined included: PremiDex™, CitriStim™, a CitriStim:PremiDex blend (50%:50%), and a commercial oligosaccharide source feedstuff. Pure culture populations of Escherichia coli O157:H7 were reduced (P < 0.05) by 2% w/v of each of: spray-dried threonine, drum-dried threonine, ethanol yeast, hyper-immunized whole egg, and a blend of CitriStim:PremiDex. Fermentations of mixed ruminal microorganisms from cattle demonstrated that 2% PremiDex reduced (P < 0.05) E. coli O157:H7 populations compared to controls in cattle fed a forage-based ration, and the CitriStim:PremiDex blend reduced E. coli O157:H7 populations (P < 0.05) in fermentations from cattle fed high-grain rations. The anti-foodborne pathogen effect appears to be an indirect effect mediated by the microbial population of the intestinal tract, similar to a probiotic effect. Further research is needed to identify modes of action of these by-product feedstuffs and impacts they have on the mixed intestinal microbial ecosystem.

Last Modified: 8/19/2014