Persistent contamination of Salmonella, Campylobacter, Escherichia coli, and Staphylococcus aureus at a broiler farm in New Zealand

Intensive poultry production due to public demand raises the risk of contamination, creating potential foodborne hazards to consumers. The prevalence and microbial load of the pathogens Campylobacter, Salmonella, Staphylococcus aureus, and Escherichia coli was determined by standard methods at the farm level. After disinfection, swab samples collected from wall crevices, drinkers, and vents were heavily contaminated, as accumulated organic matter and dust likely protected the pathogens from the disinfectants used. The annex floor also showed high microbial concentrations, suggesting the introduction of pathogens from external environments, highlighting the importance of erecting hygiene barriers at the entrance of the main shed. Therefore, pathogen control measures and proper application of disinfectants are recommended as intervention strategies. Additionally, quantitative polymerase chain reaction (qPCR) was evaluated as a quantification tool. qPCR showed limitations with samples containing low microbial counts because of the low detection limit of the method. Thus, bacterial pre-enrichment of test samples may be necessary to improve the detection of pathogens by qPCR.