鸽源大肠杆菌分离鉴定、毒力基因检测及药敏试验

Isolation,Identification, Detection of Virulence Gene and Drug Sensitivity Test of Escherichia coli from Pigeon

为了确定疑似细菌感染鸽的病原菌,以病死鸽为研究对象,进行病原菌的分离培养、生化鉴定、16S rDNA序列分析、血清型检测、动物致病性试验、毒力基因检测以及药敏试验。结果表明:此次分离的1株优势菌株,命名为QH-1,是短杆状、中等大小的革兰氏染色阴性菌,且其形态特征和生化鉴定特性与大肠杆菌相符;经16S rDNA序列分析进一步证实菌株QH-1为大肠杆菌;血清型检测结果显示,分离菌株QH-1为O26血清型分离株;动物致病性试验结果显示,分离菌株QH-1能引起鸽和小白鼠感染发病,且试验鸽发生与自然感染病例相似症状;毒力基因检测结果显示,大肠杆菌QH-1携带irp2,FyuA毒力基因;药敏试验结果显示,大肠杆菌QH-1对头孢曲松敏感;对阿莫西林、环丙沙星等耐药。疑似细菌感染的鸽病例为大肠杆菌的感染,可以选择头孢曲松进行防控。

In order to determine the pathogenic bacteria of pigeon suspected of bacterial infection,this study used a clinically ill pigeon as the test subject to conduct isolation and culture of pathogenic bacteria,biochemical identification,16S rDNA sequence analysis,stereotype detection,animal pathogenicity test,detection of virulence genes and drug susceptibility test.The results showed that a dominant strain was isolated and named QH-1.It was a short-rod,medium-sized gram-negative bacterium,and the colony morphological characteristics and biochemical identification was consistent with that of Escherichia coli;The strain QH-1 was confirmed to be Escherichia coli by further sequence analysis of 16S rDNA;the serotype test results showed that the isolated strain QH-1 was an O26 serotype isolate;animal pathogenicity test results showed that the isolated strains QH-1 could cause the infection of pigeon and mice,and pigeon infection symptoms were similar to clinical natural infection symptoms;virulence gene test results showed that Escherichia coli QH-1 carried eaeA,irp 2,and Fyu A virulence genes.Drug sensitivity test results showed that Escherichia coli QH-1 was sensitive to ceftriaxone and resistant to amoxicillin,ciprofloxacin,etc.The results showed that the pathogen of case pigeon disease was Escherichia coli,and the ceftriaxone could use to prevent and treat the disease.