Multilevel Evaluation of Preharvest Interventions to Reduce Salmonella spp. in Broiler Farms Using a Ranking Matrix

Introduction: Presence of Salmonella spp. in the food chain represents an important threat to public health. Mitigation steps are taken to reduce contamination in poultry meat during processing. Preharvest interventions are, however, often overlooked as an important opportunity for further prevention. A holistic approach to evaluate Salmonella spp. preharvest interventions demands a multilevel approach by considering several dimensions (scientific, economic, regulatory, and consumer dimensions) and sectors (government, academia, and industry).

Purpose: This study was conducted to evaluate the relative effectiveness of Salmonella spp. preharvest interventions in broiler farms using a multilevel approach and to provide broiler producers with a prioritized list of the most feasible interventions.

Methods: A literature review of interventions aimed at preventing Salmonella spp. in broiler production was performed. Interventions were included in the analysis if they met the following criteria: in vivo trials, administration of challenge strain, and observed significant reduction of Salmonella spp. A ranking matrix and a numerical score was then developed to prioritize the interventions based on the level of Salmonella spp. reduction and public health relevance, cost-effectiveness, implementation feasibility, regulatory status, and consumer acceptance.

Results: Research into consumer acceptance resulted in ranking scores assigned to interventions placed into two main categories: vaccination, with a score of zero as there is no reported impact, and probiotic feeding interventions, with a score of +1, as consumers associate positive connotations to the intervention. The scientific literature review returned 81 interventions that fit our criteria, divided into four main categories: competitive exclusion, vaccination, vaccination and competitive exclusion, and bacteriophage. A ranking matrix was applied considering reduction of Salmonella spp., trial length, number of birds tested, and type of Salmonella.

Significance: Providing producers with tools that have a multilevel approach will improve the adoption of new preharvest interventions aimed at enhancing food safety and further collaboration with academia and government.