Key Farm-to-Fork Factors Influencing E. coli Levels in Pastured Poultry Production

Area of Science:

• Microbial ecology
• Food safety
• Poultry farming

Background:

• Pastured poultry farms present unique microbial ecology challenges for food safety.
• Understanding Escherichia coli (E. coli) dynamics is crucial for risk management.

Purpose of the Study:

• Identify key factors influencing E. coli levels in pastured poultry environments.
• Compare the predictive accuracy of linear mixed-effect models (LMM) and random forest (RF) models.

Main Methods:

• Collected data from 11 southeastern US pastured poultry farms (2014-2017).
• Analyzed E. coli levels in soil, feces, ceca, and whole carcass rinses (postprocessing and final product).
• Utilized LMM and RF models with farming practices, physicochemical properties, and meteorological factors as predictors.

Main Results:

• Feces samples exhibited the highest E. coli levels.
• RF models generally outperformed LMMs in predictive accuracy (lower RMSE).
• Higher soil pH and sodium correlated with increased E. coli; higher pH also linked to fecal E. coli.
• Organic acid treatment reduced E. coli in postprocessing rinses; longer storage reduced E. coli in final product rinses.
• Mild, stable temperatures influenced E. coli survival in soil.

Conclusions:

• Farming practices and physicochemical properties are stronger predictors of E. coli than meteorological factors.
• Data-driven strategies targeting factors like soil pH, sodium, organic acid treatments, and storage time can mitigate food safety risks.