Same-day, culture-independent detection of Salmonella in chicken carcass rinsate and feed using immunomagnetic separation, whole-genome amplification, and loop-mediated isothermal amplification

Abstract

Rapid detection of Salmonella in poultry supply chains is essential for timely risk management; however, culture-based detection methods are constrained by multi-day turnaround times for results. Therefore, we developed a culture-independent workflow combining immunomagnetic separation (IMS), whole-genome amplification (WGA), and loop-mediated isothermal amplification (LAMP) targeting the conserved invA locus to enable same-day detection of Salmonella in chicken carcass rinsate and poultry feed. Fluorescence-based real-time LAMP and phenol red–based colorimetric LAMP were integrated and benchmarked against existing workflows. The IMS–WGA–real-time LAMP detected 10 CFU g−1 of Salmonella enterica serovar Enteritidis ( S. enteritidis ) in spiked carcass rinsate with a 90% detection rate (9/10) and in spiked feed with an 80% detection rate (8/10). Inclusivity and exclusivity testing using 27 Salmonella enterica strains with 23 serotypes and six non- Salmonella strains showed 100% agreement with invA targeting. The entire process, from sample preparation to obtaining results, took approximately 5 h and required minimal equipment. Overall, IMS–WGA–LAMP offers a rapid and sensitive alternative for on-site Salmonella screening in poultry-related matrices.