鸡源奇异变形杆菌的分离鉴定及系统进化分析

Isolation and Identification of Proteus mirabilis from Chickens and Analysis of Phylogenetis

从四川成都某大型养鸡场发病雏鸡的肝脏中分离到2株细菌,并对其进行细菌形态学观察、生化反应、16SrRNA扩增和药敏试验等。结果显示,该分离菌为奇异变形杆菌;药敏试验证实该菌对多种抗菌药物具有抗性,并且呈现多重耐药性;人工感染试验复制出与自然感染相同的病例,主要表现为腹泻和脑炎,并从肝、脑等实质器官回收到奇异变形杆菌,证明该菌是引起雏鸡发病的主要原因。系统发育分析表明国内鸡源的奇异变形杆菌分为不同的两大支,本试验从同一鸡场分离的2株菌聚在两个不同的分支,表明同一鸡场的奇异变形杆菌分离株也存在着遗传多样性,同时与人、牛、鹅等其他来源的奇异变形杆菌存在密切的遗传关系,其公共卫生学意义值得注意。

Two bacterial strains were isolated from liver of sick chicks in a large chicken farm in Chengdu,Sichuan province. A series experiments including bacterial morphology observation, biochemical reaction, 16 S rRNA amplification, drug sensitivity test were used. The results showed that the isolates were Proteus mirabilis, which were resistant to multiple antimicrobials, and presented the multiple drug resistance. Artificial infection test replicated the diarrhea and encephalitis as same as that of natural infection, and the strain was recycled from liver and brain. Proteus mirabilis was the main reason causing chicks ill. Phylogenetic analysis showed that domestic chicken source Proteus rnirabilis belonged to two different large branches. Two isolates were in each branches, which showed that there was genetic diversity between the isolated strains from the same chicken farm. Besides, the close phylogenetic relationship with human, cows, and geese should raise concern on public health significance.