<ol> <li>Determine the relationship between pre-harvest contamination with E. coli 0157:H7 and levels of contamination on carcasses and subsequent beef products;
<li>Reduce contamination and the numbers of pathogenic and spoil- age bacteria on carcass and subsequent products;
<li>Develop sensitive, accurate, and rapid diagnostic methods to detect foodborne pathogens;
<li>Adapt existing defense and related industry technologies for pathogen detection and control.</ol>
Animals in ongoing pre-harvest experiments will be used to determine the relationship between pre-harvest contamination and the incidence and the levels of E. coli 0157:H7 on carcasses and the subsequent beef products. Antimicrobial interventions will be used to reduce pathogens and spoilage bacteria and determine the effects of these treatments on the microbial safety of the products after refrigerated storage. This knowledge will be integrated into forms useable by the meat industry as part of a HACCP. Role of the carcass surface in bacterial attachment will be determined. Image analysis and luminometry will be used to detect low numbers of pathogenic and indicator bacteria from carcass samples. Bacteriocins will be applied to meats to inhibit bacteria emphasizing gram negative pathogens. These objectives will be modified and/or changed to meet the industry and FSIS research priorities.This research will be conducted in biosafety 2 laboratories.