Serotype, genotype, and antimicrobial susceptibility profiles of Salmonella from chicken farms in Shanghai.
Five hundred fifty samples were collected from five chicken farms in Shanghai during March 2005 to October 2006. Twenty-five samples tested positive for Salmonella from a total of 550 samples, of which 500 were obtained from feces of healthy chickens and 50 were obtained from diseased chicks. The 25 presumptive Salmonella isolates were confirmed by the API 20E identification kit. Serotyping of these isolates by agglutination tests with antiserum displayed seven serovars; genotyping of these isolates with multilocus sequence typing demonstrated six sequence type (ST) patterns (i.e., ST-11, ST-19, ST-92, ST-96, ST-290, and ST-367). The multilocus sequence typing data revealed that some of these strains, isolated from different farms, might have the same ST and might come from the same source. The susceptibilities of these strains to 14 antimicrobials were determined; most of the isolates (13 of 25) were resistant to doxycycline and tetracycline, and two isolates were resistant to cefotaxime and ceftazidime, but none was resistant to gentamicin or kanamycin.
Liu
Wei-Bing
WB
Department of Food Science and Bor Luh Food Safety Center, School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China.
Chen
Jing
J
Huang
Yan-Yan
YY
Liu
Bin
B
Shi
Xian-Ming
XM
D000818:Animals; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D002645:Chickens / Q000382:microbiology*; D002681:China; D003257:Consumer Product Safety; D004269:DNA, Bacterial / Q000032:analysis; D024901:Drug Resistance, Multiple, Bacterial; D005243:Feces / Q000382:microbiology; D005506:Food Contamination / Q000517:prevention & control*; D005516:Food Microbiology; D005838:Genotype; D006801:Humans; D008826:Microbial Sensitivity Tests; D010802:Phylogeny; D012475:Salmonella / Q000145:classification / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D012478:Salmonella Food Poisoning / Q000453:epidemiology / Q000209:etiology / Q000517:prevention & control*; D012703:Serotyping
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial