The investigation of the presence of Listeria species in poultry farms and antimicrobial resistance profiles of Listeria monocytogenes strains

Abstract

Listeria species are widespread in nature and found in various environments. In this study, the presence of Listeria species in poultry farms was investigated. For this purpose, a total of 332 samples including feces, feed, drinking water and nipple swab from 5 broiler flocks reared on the floor and 352 samples including feces, feed, drinking water and eggshell swab from 5 layer flocks reared in cages were obtained. A modified version of the USDA-FSIS MLG 8.13 method was used for the isolation of Listeria species from samples. As a result of the study, Listeria spp. was isolated from all broiler and layer flocks. Isolation of Listeria spp. was carried out from 18 of 190 feces samples (9.4%), 5 of 15 drinking water samples (33.3%), 3 of 102 nipple swab samples (2.9%) in broiler flocks, and 22 of 167 feces samples (13.1%), 2 of 25 feed samples (8%), 3 of 15 drinking water samples (20%), 3 of 145 eggshell swab samples (2%) in layer flocks. Isolates were identified by cultural and biochemical characters, and a total of 56 Listeria isolates were identified as 15 L. monocytogenes, 3 L. ivanovii, 19 L. innocua, 13 L. seeligeri, 2 L. welshimeri, and 4 L. grayi. The antibiotic resistance profiles of L. monocytogenes isolates to twelve antibiotics were detected by the disc diffusion method. L. monocytogenes isolates were found to exhibit the highest resistance to ciprofloxacin (33.3%) among twelve antibiotics, and three isolates (20%) were also multidrug resistant. Consequently, it was determined that Listeria species in poultry farms are common.