Department of Veterinary Public Health, Faculty of Veterinary Science, Chulalongkorn University, Bangkok, Thailand.
Foodborne Pathog Dis. 2010 Jan;7(1):63-9. doi: 10.1089/fpd.2009.0341.
One hundred sixty Salmonella enterica isolates from clinically healthy dairy cows were assayed for antibiotic susceptibilities, the presence of class 1 integrons, antimicrobial resistance genes and virulence genes, and conjugal transfer of antimicrobial resistance determinants. One hundred nine (68%) of the Salmonella isolates were resistant to at least 1 antibiotic, and 14 isolates (9%) were multiresistant. The most prevalent resistance observed was to streptomycin (64%). Class 1 integrons were detected in only two Salmonella isolates (serovar Singapore and Derby), and both integrons harbored the same cassette content aadA2. The Derby class 1 integrons were associated with Salmonella genomic island 1-A. Most commonly found resistance genes were strA and strB (9.2%). None of class 1 integrons were horizontally transferred, and the resistance genes were successfully transferred from six (5.5%) Salmonella strains. One hundred fifty-nine isolates (98.8%) were positive to the invasion gene invA, whereas the virulence plasmid-associated genes spvC and pefA were found in only two (1.3%) and one (0.6%) Salmonella isolates, respectively.
从 160 株来自临床健康奶牛的肠炎沙门氏菌分离株中检测抗生素敏感性、1 类整合子的存在、抗菌药物耐药基因和毒力基因，以及抗菌药物耐药决定因素的接合转移。109 株（68%）肠炎沙门氏菌至少对 1 种抗生素耐药，14 株（9%）为多重耐药。观察到的最常见耐药性是对链霉素（64%）。仅在 2 株肠炎沙门氏菌（血清型新加坡和德比）中检测到 1 类整合子，且这 2 个整合子均含有相同的盒式结构 aadA2。德比 1 类整合子与沙门氏菌基因组岛 1-A 相关。最常见的耐药基因是 strA 和 strB（9.2%）。未发生 1 类整合子的水平转移，且 6 株（5.5%）肠炎沙门氏菌菌株成功转移了耐药基因。159 株（98.8%）分离株 invA 基因阳性，而毒力质粒相关基因 spvC 和 pefA 仅在 2 株（1.3%）和 1 株（0.6%）肠炎沙门氏菌分离株中检出。
