ARS | Publication request: PRE-HARVEST SUPPLEMENTATION STRATEGIES TO REDUCE CARRIAGE AND SHEDDING OF FOODBORNE PATHOGENS

Submitted to: International Conference on Emerging Zoonoses
Publication Type: Abstract Only
Publication Acceptance Date: September 19, 2003
Publication Date: September 19, 2003
Citation: ANDERSON, R.C., CALLAWAY, T.R., JUNG, Y., BYRD II, J.A., MOORE, R., GENOVESE, K.J., EDRINGTON, T.S., HARVEY, R.B., NISBET, D.J. PRE-HARVEST SUPPLEMENTATION STRATEGIES TO REDUCE CARRIAGE AND SHEDDING OF FOODBORNE PATHOGENS. INTERNATIONAL CONFERENCE ON EMERGING ZOONOSES. 2003. ABSTRACT P. 26.

Technical Abstract: Salmonella and Escherichia coli O157:H7 are foodborne pathogens of public health and economic importance. These bacteria possess respiratory nitrate reductase activity that also catalyzes the reduction of chlorate to cytotoxic chlorite. Since most strict anaerobes lack this enzymatic activity, we hypothesized that oral administration of chlorate may selectively kill Salmonella and E. coli, but not beneficial microbes, in the gut of food animals. In support of this hypothesis, we found that Salmonella Typhimurium DT104 and E. coli O157:H7, but not total culturable anaerobes, were reduced in a dose dependent manner during in vitro incubation of buffered ruminal fluid supplemented with sodium chlorate. The reduction of pathogen concentrations exceeded 5 log10 CFU/ml within 24 h. Since then, we have demonstrated the proof of concept of this pathogen reduction technology in vivo, with practical drinking water and feed administrations reducing Salmonella and E. coli colonization in market age broilers, turkeys, pigs and cattle. More recently, we discovered that treatment of swine and poultry with select nitrocompounds resulted in significant reductions (3> log10 CFU/g) in gut concentrations of Campylobacter, another major foodborne pathogen highly prevalent in these animals. At no time were adverse effects on animal well being observed, indicating that at the relatively low concentrations used in these studies, the products were safe and efficacious. We emphasize, however, that regulatory issues have yet to be resolved before commercial use of these compounds can be approved.