摘要
本试验旨在鉴定临床疑似沙门氏菌感染致死信鸽的病原菌并确定致病菌的耐药及毒力状况。通过细菌分离培养、菌落形态观察、染色镜检、生化鉴定、血清分型、16S rRNA基因测序分析和康复信鸽血清平板凝集试验进行鉴定,并通过药敏试验、耐药基因和毒力基因检测进行耐药性和毒力分析。结果显示,分离纯化的细菌在BS、XLD、HE培养基上为黑色菌落,镜检为无荚膜、无芽孢的革兰氏阴性短杆菌;分离菌株生化反应结果符合沙门氏菌生化特性;分离菌株血清型为1,4,12:i:1,2;分离菌株16S rRNA基因序列系统进化树分析显示,该分离菌株与鼠伤寒沙门氏菌聚为一支,同源性>99%,康复信鸽血清与分离菌株发生特异性凝集,结合生化反应和血清分型结果该菌株鉴定为鼠伤寒沙门氏菌;分离菌株对氟苯尼考耐药,经耐药基因检测携带floR、cmlA氯霉素类耐药基因,与耐药表型相符;分离菌株mogA等17种毒力基因检测均为阳性。本试验成功分离到1株信鸽源鼠伤寒沙门氏菌,分离菌株对氟苯尼考耐药且具有较强毒力,为下一步信鸽沙门氏菌的防治和研究提供了参考依据。
The purpose of this research was to identify the etiology of dead pigeons which clinically suspected Salmonella infection,and to analyze the drug resistance and virulence of pathogenic bacteria.A series of tests including bacterial isolation and culture,colonial morphology observation,staining microscopy,biochemical identification,serotype analysis,16S rRNA gene sequencing analysis,serum plate agglutination test of rehabilitated racing pigeons were used for indentification,drug sensitivity test,drug resistance genes and virulence genes detection were carried out to analyze drug resistance and virulence.The results showed that the isolated bacteria were black colonies on the BS,XLD and HE medium,and the bacteria were Gram-negative short-bacillus without capsule and spores under microscope observation,the biochemical reaction results of the isolated strain conformed to the biochemical characteristics of Salmonella,the serotype of the isolated strain was 1,4,12:i:1,2.The phylogenetic tree analysis of the 16S rRNA gene sequence showed that the isolated bacterial strain and Salmonella Typhimurium were clustered into one branch with the homology>99%.Specific agglutination occurred between the serum of rehabilitated racing pigeons and isolated strain,therefore the isolated bacterial strain was identified as Salmonella Typhimurium considering the results of biochemical identification and serotype detection.The results of drug sensitivity test and drug resistance gene test showed that the isolated bacterial strain was resistant to florfenicol,the floR and cmlA genes of chloramphenicol resistance in isolated bacterial strain were detected which was consistent with the drug resistance phenotype.The isolated bacterial strain was tested positive for 17 virulence genes including mogA and so on.In this study,one strain of Salmonella Typhimurium was successfully isolated and identified from racing pigeons,which was resistant to florfenicol and had highly virulence,providing reference for the prevention and treatment of Salmonella infection in racing pigeons in the next work.
作者
张启龙
栗云鹏
傅彩霞
刘海莹
张玮
王林
吴迪
刘晓冬
周德刚
ZHANG Qilong;LI Yunpeng;FU Caixia;LIU Haiying;ZHANG Wei;WANG Lin;WU Di;LIU Xiaodong;ZHOU Degang(Beijing Center for Animal Disease Control and Prevention, Beijing 102629, China)
出处
《中国畜牧兽医》
CAS
北大核心
2021年第1期338-347,共10页
China Animal Husbandry & Veterinary Medicine
基金
北京市农业农村局科技项目(20190117)。
关键词
信鸽
鼠伤寒沙门氏菌
分离
鉴定
耐药性
毒力
racing pigeon
Salmonella Typhimurium
isolation
identification
drug resistance
virulence
