Molecular characterization of Arcobacter isolates collected in a poultry slaughterhouse

In a poultry slaughterhouse, Arcobacter contamination was examined over a period of 1 week to establish possible routes of contamination. Samples were collected from the slaughter equipment and from processing water before the onset of slaughter and from the first broiler flock slaughtered on each sampling day. Characterization of 1,079 isolates by enterobacterial repetitive intergenic consensus-polymerase chain reaction and a random amplified polymorphic DNA assay resulted in the delineation of 159 Arcobacter butzleri and 139 Arcobacter cryaerophilus types. From almost all 140 neck skin samples collected before and after evisceration, A. butzleri and A. cryaerophilus were isolated simultaneously at contamination levels ranging from 10(1) to 10(4) CFU/g. Only six A. butzleri types present in the slaughterhouse environment were also present on the broiler carcasses. None of the A. cryaerophilus genotypes were detected in both the neck skin and the environmental samples. All A. butzleri types isolated from the feather samples were also isolated from broiler neck skin samples. The slaughter equipment was contaminated with arcobacters before the onset of slaughter, but it appeared unlikely that contamination through the slaughter equipment alone explained the high contamination levels on poultry products. Arcobacters were also present in processing water, but types present in water and poultry products were different. Characterization of the Arcobacter isolates did not clarify the routes of transmission, probably because of the extreme heterogeneity among Arcobacter isolates. However, the results obtained in this study brought to light insufficient decontamination at the processing plant involved in the study and confirmed the survival capacity of certain A. butzleri strains.