中国地方と九州地方における肉用鶏および鶏肉のサルモネラ汚染実態と薬剤耐性について

抄録

Salmonella is one of the most serious food-borne zoonotic pathogens in worldwide. The purpose of this study was to determine the prevalence and antimicrobial resistance of Salmonella isolated from broilers and chicken meat products in several areas in Chugoku and Kyusyu region. The cecal content samples were collected from 185 broilers derived from 37 flocks from 32 farms in Chugoku region and 155 broilers derived from 31 flocks from 28 farms in Kyusyu region. Chicken meat samples (n=20) were collected from the broiler meat processing plant in each region. The antimicrobial susceptibility test of the isolates was performed by broth microdilution testing. Salmonella was prevalent among 87 (47.0%) broilers of 31 flocks from 27 farms in Chugoku region. S. Schwarzengrund is the predominant serovars in the broilers from both regions, and they presented high rates of resistance to antibiotics. In Chugoku and Kyusyu region, S. Schwarzengrund isolates (n=226, and n=177, respectively) were resistant to ampicillin, 0.9 and 0%; cefotaxime, both regions 0%; streptomycin, 100 and 92.1%; kanamycin, 47.3 and 83.6%; tetracycline, 96.5 and 90.4%; nalidixic acid, 0 and 11.3%; and trimethoprim, 97.8 and 84.2%, S. Infantis isolates in Chugoku region (n=43) were resistant to ampicillin, 34.9%; cefotaxime, 32.6%; streptomycin, 100%; kanamycin, 0%; tetracycline, 100%; nalidixic acid, 0%; and trimethoprim, 0%. All isolates were susceptible to gentamicin, chloramphenicol and ciprofloxacin. Our results suggested that there are regional differences in antimicrobial resistance patterns of Salmonella originated from broilers in study region to such as kanamycin.