本研究采用纸片扩散法对生鲜食品源沙门氏菌分离株进行耐药表型检测，玻片凝集法测定血清型，MLST方法分析其序列型。用PCR检测结合序列比对，对多重耐药沙门氏菌携带的的Ⅰ类整合子及其基因盒、ISCR1及其基因盒进行分析。共筛选出32 株多重耐药菌株，多重耐药率为48.48%。多重耐药株中分为11 种血清型，优势血清型为S. Thompson（21.88%）和S. Agona（18.75%），MLST的序列分型将多重耐药株分为15 种ST型，优势序列型为ST26（21.88%）和ST13（12.50%）。多重耐药菌株中，Ⅰ类整合子的检出率为43.75%（14/32），其中有5 株扩出耐药基因盒，检出率为35.71%（5/14）；11 株检出ISCR1序列，检出率为34.38%（11/32），其中4 株扩增出耐药基因盒，检出率为36.36%（4/11）；同时含有这两种遗传元件（Ⅰ型复合整合子）的菌株共检测出9 株，检出率为28.13%（9/32），检出的基因盒大多包含1-2 种耐药基因，与耐药表型具有较好的相关性。通过blast比对，发现28号菌株中的Ⅰ型复合整合子耐药基因盒与沙门氏菌Nsa217质粒和肺炎克雷伯菌的KP15-2-53质粒具有同源性。生鲜制品中沙门氏菌耐药性相对严重，且沙门氏菌多重耐药性与携带的Ⅰ型复合整合子之间具有相关性。

In this study, the disk diffusion method was used to analysis the drug resistance phenotype of Salmonella isolates,The serum type was determined by glass slide agglutination.MLST method was used to analyze the sequence type. PCR was used to detect the class I integron gene, ISCR1 and drug resistance gene cassettes in the isolates..A total of 32 multi-drug resistant strains were screened, and the multi-drug resistant rate was 48.5%. The multi-drug resistant strains were divided into 11 serotypes, S. Thompson(21.88%)and S. Agona(18.75%)were the dominant serotypes。MLST sequence typing divided the multi-drug resistant strains into 15 sequence types(STs)and the dominant ST were ST26 (21.88%),and ST13 (12.50%). In the multi-drug resistant strains, the positive detection rate of class I integron gene was 43.75% (14/32), and 5 strains included resistance genes, the detection rate was 35.71% (5/14). ISCR1 was detected in 11 isolates (34.38%, 11/32), and drug-resistant gene boxes were amplified in 4 isolates(36.36%, 4/11). Nine strains contain both genetic element(composite integron Ⅰ), and the detection rate was 28.13%(9/32). The detected gene cassettes generally contained one or two drug resistant genes, and has good correlation with the resistant phenotype. By blast alignment, It was found that gene cassette arrangement of No. 28 strain was similar to that of Salmonella Nsa217 plasmid and the Klebsiella pneumoniae KP15-2-53 plasmid.. Drug resistance of Salmonella isolates from fresh products of is relatively serious, and multi-drug resistance of Salmonella has correlation with composite integron Ⅰ prevalence.

TS201.6