Location: Egg Safety & Quality ResearchTitle: ANTIMICROBIAL SENSITIVITY PATTERNS OF MAJOR ZOONOTIC PATHOGENS FROM A SEASON-LONG “FARM-TO-FORK” STUDY OF ALL NATURAL, ANTIBIOTIC-FREE, PASTURE-RAISED BROILER FLOCKS IN THE SOUTHEASTERN UNITED STATES Author
Submitted to: Campylobacter Helicobacter and Related Organisms International Workshop
Publication Type: Abstract Only
Publication Acceptance Date: 8/1/2015
Publication Date: 11/1/2015
Citation: Rothrock Jr, M.J., Hiett, K.L., Guard, J.Y., Jackson, C.R. 2015. ANTIMICROBIAL SENSITIVITY PATTERNS OF MAJOR ZOONOTIC PATHOGENS FROM A SEASON-LONG “FARM-TO-FORK” STUDY OF ALL NATURAL, ANTIBIOTIC-FREE, PASTURE-RAISED BROILER FLOCKS IN THE SOUTHEASTERN UNITED STATES. Campylobacter Helicobacter and Related Organisms International Workshop. November 1-5, 2015. Rotorua, New Zealand. Interpretive Summary:
Technical Abstract: Background: The prevalence of antibiotic resistance microorganisms has significant implications for environmental, animal, and human health. One focus is the use of antibiotics in animal agriculture and its effects on antibiotic resistant bacterial populations within those systems, but before this causal effect can be elucidated, a greater understanding of the background/reference levels of antibiotic resistance devoid of antibiotic use is needed. Objectives: What are the antibiotic resistance profiles of bacteria in agricultural production environments when antibiotics are not used for production purposes? All-natural, pasture-raised production systems where antibiotics are not used nor have been used historically should allow us to better determine background levels of antibiotic resistance in relevant bacteria associated with broiler chicken production. Methods: 15 all-natural, pasture-raised broiler flocks were sampled along the entire “farm-to-fork” continuum, including fecal and soil samples during grow-out, cecal content and carcass rinses during processing, and carcass rinses of the final products delivered to the consumer. Traditional culture methods were used to isolate 3 zoonotic bacterial pathogens (Salmonella, Campylobacter, and Listeria) and generic Escherichia coli and their resistance profiles were determined using the CDC’s NARMS protocol. Conclusions: Sensitivities to a variety of antibiotics were found for not only generic E. coli isolates, but also for the three zoonotic bacterial pathogens, from various points along the “farm-to-fork” continuum. While not surprising, these results show that background levels for resistance in these production systems need to be considered when determining the causal effect of antibiotic use within the production animals to the proliferation of antibiotic resistance organisms.