The objective of this study was to use microplate immunocapture (IC) to reduce the enrichment time required for detection of Salmonella in pet food with loop-mediated isothermal amplification with bioluminescent assay in real time (LAMP-BART) and selective plating on XLD. Dog food and pig ear treats were inoculated with Salmonella Infantis at concentrations of 10 0-10 4 CFU/25 g, followed by a 3-h enrichment, then microplate IC and LAMP-BART or microplate IC and selective plating on XLD. Another set of samples underwent a traditional 24-h enrichment followed by LAMP-BART or selective plating. Based on the results of three independent trials, microplate IC followed by selective plating enabled detection of Salmonella in 100% of dog food and treat samples tested, including at levels as low as 10 0 CFU/25 g. Microplate IC coupled with LAMP-BART enabled detection of Salmonella in dog food and treat samples down to levels of 10 0 CFU/25 g, with overall detection rates of 90-93%. These results indicate high potential for microplate IC to be used in place of the traditional 24-h enrichment step, enabling detection of Salmonella in complex matrices when coupled with LAMP-BART or selective plating.

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