A Systematic Review on Preharvest Interventions Used to Control Salmonella in Poultry Rearing in the United States

Preharvest interventions can play an important role in reducing Salmonella prevalence and levels entering poultry slaughter and processing establishments. Currently, there is no systematic literature review of preharvest interventions that control Salmonella in poultry in the United States (U.S.). The objective herein was to synthesize literature published on the effectiveness of preharvest interventions in U.S. poultry production. Utilizing the Methodological Expectations of Cochrane Intervention Reviews guidelines, a literature search was conducted. Experimental studies published from 1995 to 2022 assessing preharvest interventions to control Salmonella in U.S. poultry farms were included in the review if they reported prevalence or levels of Salmonella. Data were extracted from each article by two reviewers. Descriptive statistics were used to summarize key study parameters, (e.g., study design, study location, poultry type, Salmonella serotypes, type of intervention) and effectiveness of intervention. A total of 12,403 publications were identified, and 234 publications were included in the final review. The most evaluated interventions were feed/water additives (51.50%), competitive exclusion culture (10.30%), vaccination/immunization (7.88%), chemical treatments/compounds (5.45%), and probiotic culture (4.85%). Most studies focused on broiler chicken (78.20%) compared to turkey and investigated Salmonella Typhimurium (37.60%), S. Enteritidis (29.10%), and S. Heidelberg (8.48%). Overall, the effectiveness of evaluated interventions varied, though one should consider differences may be due to study design, sample sizes, and duration of interventions. This review improves our understanding of the breadth of preharvest interventions and their effectiveness against Salmonella in poultry and can be used to inform food safety policies and practices around poultry to protect public health.