4型鸭疫里默氏杆菌的分离鉴定及其不同感染途径致病性和传播方式的研究  

Isolation and identification of Riemerella anatipestifer serotype 4 strain and its pathogenicity and transmission mode in different infection routes

作　　者：沈扬扬 马芹 汪建华 褚新星 马元元 张晓宇 刘子涵 魏书强 于堃 石艳红 卢博敏 郭明 高月花[2,3] 李玉峰 SHEN Yang-yang;MAQin;WANG Jian-hua;CHU Xin-xing;MAYuan-yuan;ZHANG Xiao-yu;LIU Zi-han;WEI Shu-qiang;YU Kun;SHI Yan-hong;LU Bo-min;GUO Ming;GAO Yue-hua;LI Yu-feng(Shandong Hekangyuan Biological Breeding Co.,Ltd.,Jinan 250001,China;The Poultry Institute of Shandong Academy of Agricultural Sciences,Jinan 250023,China;Poultry Breeding and Disease Control Shandong Engineering Research Center,Jinan 250001,China)

机构地区：[1]山东和康源生物育种股份有限公司,山东济南250001 [2]山东省农业科学院家禽研究所,山东济南250023 [3]家禽育种与疫病控制山东省工程研究中心,山东济南250001

出　　处：《中国预防兽医学报》2025年第2期124-129,151,共7页Chinese Journal of Preventive Veterinary Medicine

基　　金：山东省农业良种工程(2022LZGC014);山东省农业科学院农业科技创新工程(CXGC2021B22)。

摘　　要：为研究4型鸭疫里默氏杆菌(RA-4)对商品肉鸭的致病性及传播规律,本实验对疑似感染RA的病死鸭肝脏、脑组织进行细菌的分离培养与纯化,并进行生化试验、血清型鉴定,16S r RNA的PCR扩增及测序,采用K-B纸片法检测其药敏性。结果显示分离到1株RA-4,该分离株符合RA的生化特征;PCR扩增及测序分析该分离株与RA16S r RNA基因的同源性在99.04%~99.47%;该分离株对恩诺沙星、多西环素、头孢吡肟等9种实验室常用药物均耐药,对氟苯尼考、大观霉素、头孢噻肟3种药物中介,表明该菌株为多重耐药菌株。将SPF番鸭分为5组(饮水感染组、空气感染组、肌肉注射组、接触组及对照组),每组采用相应的感染方式均感染0.5 m L/只分离菌液(1.0×10~7cfu/m L),其中接触组与肌肉注射组置于同一隔离器中,对照组单独饲养,感染后检测各组鸭的存活率,感染后不同时间采集各组鸭的喉头、泄殖腔拭子,采用PCR检测各组鸭的排毒情况,并剖检后观察各组鸭各脏器的剖检病变。结果显示,肌肉注射组鸭的存活率最低(30%),且显著低于其他4组(P<0.05);每组SPF鸭感染后的喉拭子均能检出RA,仅少部分泄殖腔拭子检出RA;各组鸭各脏器的剖检与组织病变观察结果显示,该分离株可引起鸭的死亡以及纤维素性心包炎和肝周炎等炎症性病变。上述结果表明,本研究从商品肉鸭中分离到1株RA-4,其对SPF鸭致病性较强,且其主要经呼吸道途径水平传播。本研究为临床感染RA-4的诊断和防控提供了参考依据。To study the pathogenicity and transmission patterns of Riemerella anatipestifer type 4(RA-4)in commercial meat ducks,the bacteria were isolated and purified from the liver and brain tissues of dead ducks suspected of RA infection,and biochemical tests,16S rRNA PCR amplification and sequencing,serotype identification and drug sensitivity tests were subsequently conducted.The results showed that one strain of RA-4 was isolated,consistent with the biochemical results of RA.The homology of the 16S rRNA gene of this isolate to RA ranged from 99.04%to 99.47%,as determined through PCR amplification and sequencing.The isolate was resistant to 9 commonly used drugs in laboratory such as enrofloxacin,doxycycline,and cefepime,and was moderately sensitive to florfenicol,spectinomycin,and cefotaxime,indicating that this strain was a multi-drug resistant strain.SPF Muscovy ducks were divided into 5 groups(drinking water infection group,air infection group,intramuscular injection group,contact group and control group),and each group received 0.5mL of the isolated bacterial suspension(1.0×107cfu/mL)per duck according to the corresponding infection method.The contact group and the intramuscular injection group were placed in the same isolator,while the control group was raised separately.After infection,the survival rate of each group was detected,as well as the shedding of RA in throat and cloacal swabs,and the lesions were observed after autopsy and histological examination.The results showed that the intramuscular injection group had the lowest survival rate at 30%,significantly lower than those of the other 4 groups.RA could be detected in throat swabs of infected SPF ducks in all groups,while only a few cloacal swabs were positive for RA.The autopsy and histological examination results showed that this isolate led to death and fibrinous pericarditis and perihepatitis in ducks.The above results confirmed that a strain of RA-4 was isolated from commercial meat ducks,demonstrating high pathogenicity to SPF ducks and primarily

关 键 词：鸭疫里默氏杆菌 分离鉴定 感染途径 传播方式 

分 类 号：S852.61[农业科学—基础兽医学]