Characterization of Listeria monocytogenes Isolated from Retail Organic Chicken

Abstract

Listeria monocytogenes is an important foodborne pathogen. It is commonly found in the environment, frequently present in the gut of cattle, poultry, and pigs and can be transmitted to ready-to-eat foods as well as raw meat products. However, no data are available on the prevalence of L. monocytogenes in organic foods. In this study, 210 organic chickens collected from retail stores in the Washington DC area were examined for the presence of Listeria sp. using a modified Food and Drug Administration protocol developed to isolate the organism from meat products. Forty-eight organic chickens were positive for L. monocytogenes. The isolates were serotyped using PCR and subtyped by Pulsed-field gel electrophoresis (PFGE) to determine their genetic relatedness. The data revealed that several Listeria sp. were present on raw retail chicken and L. monocytogenes serotypes associated with human listeriosis were also identified in the product.