EVALUATION OF TWO COMMERCIAL REAL‐TIME PCR ASSAYS FOR DETECTING CAMPYLOBACTER IN BROILER CARCASS RINSES*

Abstract

ABSTRACT Traditional plating methods are reliable means for Campylobacter identification from poultry samples but automated gene‐based detection systems now available can reduce assay time, data collection and analysis. Bio‐Rad and DuPont Qualicon recently introduced Campylobacter assays for their real‐time polymerase chain reaction (PCR) instruments. We evaluated the utility of these assays compared with standard plating and enumeration methods routinely used in our laboratory. Two replicates of 40 broiler carcass rinses collected before and after defeathering at a commercial processing plant were tested. All samples were positive for Campylobacter by direct plating of rinses: log10 cfu values ranged from 0.24 to 4.61. In contrast, the Bio‐Rad iQ‐Check assay returned 60–72.5% positives on direct rinses; the Qualicon BAX Q7 test produced 60–85% positives with direct rinse samples. Using aliquots of 24 h enrichment broth from rinses in the real‐time assays significantly improved detection: the Bio‐Rad test had 95–100% positive while the Qualicon assay found 90–95% positive.PRACTICAL APPLICATIONSTraditional detection methods for Campylobacter are time‐consuming, requiring as much as 5 days to complete. The recent introduction of commercial real‐time PCR instruments for the identification of Campylobacter offer more rapid, simplified alternatives to standard culture‐based techniques.