Assessing the Effect of Interventions on Pathogens and The Microbial Ecology of the Poultry Processing Chain by Microbial Profiling and the Phenotypic and Genotypic Characterization of Antimicrobial Resistance

Salmonella and Campylobacter continue to be major foodborne pathogens in the U.S. and poultry is one of the leading carriers of these bacteria. During the poultry processing operations, the risk of contamination by any pathogen might be present. Despite the constants effort to improve the food safety systems to control foodborne pathogens, the survival and antimicrobial resistance of poultry-associated pathogens are persistence through the processing. Antimicrobial resistance is a serious public and animal health problem. The use of antimicrobials in animal-food production has been an important factor in the emerge of antimicrobial resistant bacteria. Multi-drug resistance Salmonella and Campylobacter strains have been associated with multiple outbreaks liked to chicken meat and chicken meat products. Hence, microbial profiling can serve as an essential tool to identify pathogen sources and the effect of selective pressures in the poultry processing chain that is favoring the dissemination of resistant pathogens. This dissertation outlines the research conducted in four sections: 1) Evaluation of the efficacy of antimicrobials to reduce Salmonella on chicken parts under simulated commercial conditions, 2) Microbial profiling and antimicrobial resistance characterization of Salmonella strains isolated from chicken carcasses rinsate samples collected at different stages during processing, 3) Microbial profiling of three poultry processing plants, and 4) Phenotypic and genotypic characterization of Salmonella strains isolated from poultry processing plants in Colombia.