Integrating Aerated Water and Peracetic Acid for Effective Salmonella Control on Hatching Eggs

Introduction: Along the farm-to-fork continuum, hatcheries represent a critical control point for the entry of Salmonella Enteritidis (SE) into poultry production. Contaminated hatching eggs can lead to SE colonization of developing embryos, SE-positive hatchlings, and subsequent dissemination to grow-out farms. Therefore, early-stage interventions to reduce SE contamination are essential to minimize transmission through the egg-to-chicken pipeline. This study evaluated novel application of aerated water (AW) as a potential, user-friendly, and natural antimicrobial intervention to reduce SE contamination on broiler hatching eggs.

Methods: Broiler hatching eggs (n=150) were inoculated with a four-strain cocktail of SE (~7 log CFU/egg) and subjected to one of five spray treatments: untreated control, tap water (TW), aerated water (AW; 30 mg/L), tap water + peracetic acid (TP; 80 ppm PAA), and aerated water plus peracetic acid (AP). Eggs were incubated for 18 days, with the SE population enumerated post treatment (day 0) and on days 1, 3, 10, 14, and 18. Five eggs per treatment group were sampled at each time point. Data were analyzed using GraphPad, with significance set at p≤0.05.

Results: Our data demonstrated a clear antimicrobial benefit of AW and AP treatments. AW reduced SE by >1.5 log CFU immediately after treatment (day 0), with no detectable SE recovered at subsequent time points, whereas no SE were recovered in the AP-treated eggs throughout the 18-day incubation period. In contrast, eggs treated with TP maintained a detectable population through day 18, indicating reduced efficacy when PAA was applied without aeration. TW treatment had minimal effect on SE levels, comparable to untreated controls. The sustained reduction in or absence of SE on AW- and AP-treated eggs underscores their effectiveness in disrupting SE persistence during incubation.

Conclusion: Aerated water when combined with PAA, is a highly effective, organic-friendly intervention for reducing Salmonella contamination on hatching eggs. This approach can enhance hatchery biosecurity and significantly limit pathogen transmission within the poultry production chain.