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ARS Home » Southeast Area » Athens, Georgia » U.S. National Poultry Research Center » Egg and Poultry Production Safety Research Unit » Research » Publications at this Location » Publication #397202

Research Project: Reducing Pathogen Contamination Risks and Improving Quality Attributes of Eggs and Egg Products through Housing System Management and Egg Handling Practices

Location: Egg and Poultry Production Safety Research Unit

Title: Salmonella in eggs and egg-laying chickens

item Gast, Richard
item DITTOE, DANA - University Of Wisconsin
item RICKE, STEVEN - University Of Wisconsin

Submitted to: Critical Reviews in Microbiology
Publication Type: Review Article
Publication Acceptance Date: 12/5/2022
Publication Date: 12/30/2022
Citation: Gast, R.K., Dittoe, D.K., Ricke, S.C. 2022. Salmonella in eggs and egg-laying chickens. Critical Reviews in Microbiology.

Interpretive Summary:

Technical Abstract: Eggs contaminated with Salmonella have been internationally significant sources of human illness for several decades. Substantial resources (both public and private) have been committed to comprehensive risk reduction and monitoring programs to reduce the prevalence of Salmonella in commercial egg-producing flocks. Both research and field experience have demonstrated that the most effective overall Salmonella control strategy in layers is the application of multiple interventions throughout the egg production cycle. Most egg-associated illness has been attributed to Salmonella serovar Enteritidis, but a few other serovars (notably S. Heidelberg and S. Typhimurium) have also sometimes been implicated. The edible interior contents of eggs typically become contaminated with S. Enteritidis as a result of the pathogen’s propensity to colonize the reproductive tissues in systemically infected laying hens. Other serovars are more commonly associated with surface contamination of eggshells. Careful regulation of egg storage temperatures is critical for limiting Salmonella multiplication, especially inside the interior contents. Minimizing opportunities for the introduction, transmission, and persistence of Salmonella in laying flocks depends on effective management of their environmental and housing conditions. The various available systems for housing commercial egg flocks are each characterized by unique risk factors and management challenges for Salmonella control.