养殖环境病原菌以及超级细菌气溶胶的发生与传播的监测

为了观察和评估养殖环境耐药细菌气溶胶的形成与扩散,采用Andersen-6级空气样品收集器在养鸡场鸡舍环境舍内、外(到下风方向800 m)收集空气样品;与此同时,采集鸡只粪便样品。对样品分离的大肠杆菌(E.coli)进行药物敏感性测试。结果显示,各个地点分离的E.coli对利福平和青霉素完全耐药,但他们对妥布霉素、庆大霉素敏感;有不同数量的菌株对氟哌酸、链霉素、头孢哌酮、氯霉素、复合磺胺和四环素有不同程度的耐药性。采用多重PCR方法,分别对从鸡、猪、牛舍(共21个)及其环境中分离到的480株大肠杆菌,进行了5种毒素基因即STa,STb,LTa,Stx1和Stx2/Stx2e的检测。结果表明,分离株都携带有一定数量的毒素基因,很多携带2种或2种以上。通过对11个动物舍(鸡、猪、牛、兔)空气和粪便样品分离的426株肠球菌对四环素类(TetM)、氨基糖甙类抗生素及万古霉素VanA和VanB主要耐药基因的检测表明,14.55%的细菌对β-内酰胺酶耐药;分离株都存在不同程度的对四环素类抗生素的耐药性;共检测出31株肠球菌携带vanA和vanB耐药基因;绝大多数肠球菌携带氨基糖苷修饰酶(AME)基因的一种或几种。

Monitoring of Occurrence and Spread of the Pathogenic Bacteria and the Super Bacteria Aerosol in Animal Breeding Environment

In order to observe and assess the formation and spread of Antibiotic-resistant bacteria aerosol,indoor and outside air（downwind 800 m away）samples were collected using six-stage Andersen microbial sampler,and meanwhile chicken fecal samples were also collected.The E.coli isolated from the samples were conducted on the antibiotics sensitivity testing.The results showed that E.coli isolated from various locations were completely resistant to Rifampicin and Penicillin,while they were sensitive to TOB and GEN.A different number of strains had different degrees of resistance against Norfloxacin,Streptomycin,Cefoperazone,Chloramphenicol,Sulfonamides and Tetracycline.By using Multiplex PCR,5 toxin genes：STa,STb,LTa,Stx1 and Stx2/Stx2e of 480 E.coli strains were detected,which were isolated from chicken,pig and cow houses（total 21）and its environment respectively.The results showed that all isolates carried a certain amount of toxin genes,many carrying 2 or more than 2.Altogether 426 strains of Enterococci isolated from indoor,outdoor air and fecal samples of 11 animals stables（chicken,pig,cattle,rabbit）were conducted on the antibiotics sensitivity testing.The results showed that 14.55% bacteria resistant against β-lactam antibiotics;the isolates have varying degrees of resistance to Tetracyclines;31 strains of Enterococci carried vanA and vanB resistance gene;and the majority of Enterococci carried one or several of Aminoglycoside modifying enzymes（AME）genes.