Prevalence and antimicrobial resistance of Salmonella isolated from poultry slaughterhouses in Korea

We determined the antimicrobial resistance of Salmonella serovars from a total of 154 (44 chilling waters and 110 carcasses) samples collected from 22 poultry slaughterhouses. Standard culture techniques, Kauffmann-White slide agglutination and disc diffusion tests were used to isolate, and identify the serovars and to assess the antimicrobial activity, respectively. A total of 88 isolates belonging to 34 Salmonella serovars from 67 (43.5%) positive samples were identified. Among the samples examined, 68.2% (15/22), 22.7% (5/22), and 42.7% (47/110) from the first chilling waters, the last chilling waters, and carcasses were found contaminated with Salmonella, respectively. The prevalent serovars were S. Enteritidis (12.5%) followed by S. Montevideo and S. Senftenberg (8.0%). Rare Salmonella serovars such as S. Aba, S. Malmoe, S. Westhampton, S. Takoradi, and S. Baiboukoum in chicken slaughterhouses and S. Newbrunswick, S. Huddinge S. Glostrup, S. Dujugu, S. Goettingen and S. II in duck slaughterhouses were also detected. Among the serovars, 52.3% (46/88) and 21.6% (19/88) were resistant to one antibiotic and more than two antibiotics, respectively. High antimicrobial resistance rates against sulfamethoxazole (39.8%) followed by tetracycline (22.7%), nalidixic acid (21.6%), ampicillin and amoxicillin-clavulanic acid (8.0%), and chloramphenicol (4.5%) were observed. These results suggest more stringent hygienic measures should be taken to reduce the incidence of pathogen contamination in the food chain.