Occurrence of Listeria species in retail poultry meat and comparison of a cultural/immunoassay for their detection

The prevalence of Listeria spp. on the skin of a hundred fresh chicken carc asses purchased from 20 retail stores in Leon was investigated using the ro utine test procedure recommended by the United States Department of Agricul ture (USDA). PALCAM and Modified Oxford agar (MOX) were used for isolation. Listeria spp., Listeria monocytogenes, L. innocua, L. welshimeri, L. grayi and L. ivanovii were present in 95%, 32%, 66%, 7%, 4% and 2% of the sample s, respectively. Next, an immunoassay test (Listeria Rapid Test; Oxoid, Uni path) and the routine test procedure (USDA) were compared fur their ability to detect Listeria spp. on 40 chicken carcasses. When we used MOX for the isolations, the sensitivity of the immunoassay test was 100% and the specif icity 85.7%. When we used PALCAM medium the sensitivity and specificity of the test was 94.29% and 80%, respectively. (C) 2001 Elsevier Science B.V. A ll rights reserved.