散养鸡鼠伤寒沙门氏菌的分离·鉴定·耐药性研究

Identification and Drug Resistance Analysis of Salmonella typhimurium from Free-range Chicken

从疑似感染的成年散养鸡蛋壳和发病雏鸡的肝脏、脾脏中分离到2株细菌,通过培养特性、镜检结果、生化鉴定、血清学分型等,2株分离细菌均被鉴定为鼠伤寒沙门氏菌,分别命名为AH-DY01和AH-DY02。药物敏感性检测结果表明,AH-DY01对氟苯尼考、左氧氟沙星和环丙沙星敏感,对其他12种抗生素耐药;AH-DY02对阿米卡星、氟苯尼考、左氧氟沙星、复方新诺明、庆大霉素、链霉素、环丙沙星和大观霉素敏感,对其他7种药物耐药,2株沙门氏菌均表现多重耐药性。动物回归试验结果表明,2株鼠伤寒沙门氏菌均可致死雏鸡。对分离菌的16S r DNA进行测序与遗传进化分析,结果表明AH-DY01与标准菌株ATCC-1592和ATCC13311的同源性最高,而AH-DY02与日本分离株之间的亲缘关系最近。

Two bacterial strains were isolated from the eggshells of free-range hens and the liver and spleen of diseased chicks.Salmonella ty-phimurium strains AH-DY01 and AH-DY02 were identified according to culture characteristics, microscopic examination, biochemical charac-teristics, serological typing and so on.Drug sensitive test showed that the AH-DY01 was sensitive to florfenicol, levofloxacin and ciprofloxa-cin, and was resistant to other 12 antibiotics.AH-DY02 was sensitive to amikacin, florfenicol, levofloxacin, ciprofloxacin, Trimethoprim-Sul-famethoxazole（ TMP-SMZ） , gentamicin, streptomycin and spectinomycin, and was resistant to other 7 antibiotics.Two strains of Salmonella typhimurium showed multi-drug resistant.Animal experimental results showed that the two strains both could cause chicken death.16S rDNA sequencing and phylogenetic analysis showed that homology of AH-DY01 with standard strain ATCC-1592 and ATCC 13311 was the highest, while there was the highest homology between AH-DY02 and Japan isolated strains.