Improving the Detection Accuracy and Time for Campylobacter jejuni and Campylobacter coli in Naturally Infected Live and Slaughtered Chicken Broilers Using a Real-Time Fluorescent Loop-Mediated Isothermal Amplification Approach

Abstract

ABSTRACT Rapid and accurate identification of Campylobacter-positive broiler flocks and carcasses expedites separation and control interventions before release into the food supply chain and directly facilitates a reduction in the prevalence of human campylobacteriosis. In this study, the diagnostic performance of fluorescent loop-mediated isothermal amplification (LAMP) assays for the direct detection of Campylobacter jejuni and Campylobacter coli in broiler cloacal and cecal samples were evaluated and compared with that of turbidimetric LAMP approaches investigated previously. The duplex fluorescent LAMP assay had significantly higher (P < 0.05) diagnostic sensitivity (93.1%, 54 of 58 samples) than did the turbidimetric LAMP assay (82.8%, 48 of 58 samples) for detecting C. jejuni and C. coli in broiler cloacal samples, whereas the singleplex fluorescent LAMP assay had equivalent diagnostic sensitivity. For cecal samples, the diagnostic sensitivity of the fluorescent LAMP assay (100%, 38 of 38 samples) was the same as that of the turbidimetric LAMP. Fluorescent LAMP significantly reduced (P < 0.05) the maximum detection time for Campylobacter-positive cloacal and cecal samples to 28 and 11 min, respectively, and reduced the influence of amplification inhibitors responsible for most false-negative results obtained for cloacal samples with the turbidimetric LAMP assay. The diagnostic accuracy of the fluorescent LAMP assay for the direct detection of C. jejuni and C. coli in cloacal and cecal samples was 97.7 and 100%, respectively. These findings indicate that fluorescent LAMP assays are robust, highly accurate, and field-applicable methods for the identification of C. jejuni and C. coli, which will allow more accurate monitoring of food safety at various stages of the food supply chain at farms and slaughter facilities.