羊布鲁氏菌病的正确防控

羊布鲁氏菌病是一种人畜共患病,是一个需要重点预防控制的疫病.本文分析了羊布鲁氏菌病的病原学,总结了近代防控本病的成功经验,旨在纠正兽医和养殖户的认识误区.1病原学羊布鲁氏菌病的致病原是布鲁氏杆菌(Brucella),革兰氏阴性,绝对需氧菌(非抗酸性),无芽孢,无荚膜,无鞭毛,不能运动,寄生于动物体细胞内.布鲁氏菌属包括6个种19个型,其中羊种布鲁氏杆菌有3个型、绵羊附睾种布鲁氏杆菌有1个型,羊种布鲁氏杆菌致病力最强且人畜均易感,所以羊布鲁氏菌病属于人畜共患病.     

羊种布鲁氏菌疫苗株PCR-RFLP鉴定方法的建立

为建立一种羊种布鲁氏菌Rev.1疫苗株PCR-RFLP鉴定方法,利用羊种布鲁氏菌Rev.1具有链霉素抗性的特性,选取与链霉素抗性相关编码核糖体蛋白S12的rps L基因为模板设计引物,经PCR扩增后,将产物进行Nci I酶切,发现羊种布鲁氏菌疫苗株Rev.1出现约500 bp条带,而不具有链霉素抗性的羊种布鲁氏菌株16M则出现384 bp条带。结果表明,PCR-RFLP方法能够用于羊种布鲁氏菌Rev.1疫苗株的鉴定,这为今后区分羊种布鲁氏菌疫苗株Rev.1免疫与野株感染提供了基础。     

布鲁氏菌omp28基因的克隆、表达及反应原性分析

本研究克隆了羊种布鲁氏菌16M株、羊种布鲁氏菌M28株、犬种布鲁氏菌、绵羊附睾种布鲁氏菌、牛种布鲁氏菌A19株、猪种布鲁氏菌S2株的omp28基因并对以上不同种菌株的omp28基因序列及编码的氨基酸序列进行了比对,结果显示不同种布鲁氏菌omp28基因之间仅6个碱基不同,而且只有2个氨基酸不同,亲水性分析结果显示两处氨基酸的差异对蛋白亲水性不造成影响.将羊种布鲁氏菌16M的omp28基因亚克隆到pET32a中表达,OMP28在低温下诱导以可溶性形式高效表达.Westem-blot结果显示OMP28反应原性良好,是布鲁氏菌病诊断抗原的可能选择.     

羊种布鲁氏菌Rev.1疫苗株VirB12基因缺失株的构建及鉴定

为获得毒力较弱且能够区分疫苗免疫与自然感染的羊种布鲁氏菌候选疫苗株,本研究构建羊种布鲁氏菌Rev.1疫苗株VirB12基因缺失突变株。分别扩增Rev.1疫苗株VirB12基因上下游同源臂序列以及卡那霉素抗性基因,采用融合PCR方法将3个基因片段连接构建突变盒,连接至pMD19-T载体,电转化入布鲁氏菌Rev.1感受态细胞筛选阳性克隆,获得Rev.1-ΔVirB12突变株。Rev.1-ΔVirB12连续传代15代未发生回复突变。羊种布鲁氏菌疫苗株Rev.1-ΔVirB12的构建为羊种布鲁氏菌疫苗研制奠定了基础。     

羊种布鲁氏菌生物3型的分离和鉴定

本实验对新疆某羊场小尾寒羊5只流产胎儿进行布鲁氏菌病原分离、鉴定,结果从5只流产胎儿胃内容物中均分离到羊种布鲁氏菌生物3型。表明新疆羊群中存在羊种布鲁氏菌生物3型病原。     

动物布鲁氏菌病疫苗的研究进展

疫苗免疫是布鲁氏菌病防控的主要措施之一,目前,动物使用的布鲁氏菌疫苗主要有牛种布鲁氏菌A19菌株弱毒疫苗、羊种布鲁氏菌M5菌株弱毒疫苗、羊种布鲁氏菌Rev.1弱毒疫苗和猪种布鲁氏菌S2菌株弱毒疫苗。正在研发的疫苗主要有基因工程弱毒活疫苗和基因工程活载体疫苗,各种疫苗均存在优缺点,本文对动物布鲁氏菌疫苗的应用情况进行概述。     

山区山羊布鲁氏菌病的监测报告

正布鲁氏杆菌病(以下称布病)是由布鲁氏菌杆菌引起的人畜共患传染病,临床上以牛、羊、猪种布鲁氏菌最为常见,其中羊种布鲁氏菌的致病力最强,约80%的人感染病例由羊布鲁氏菌引起。本文通过对2017～2019年88个山羊养殖场的饲养、引种等生产情况进行调查,采取检测-扑杀-监测-净化等综合防控措施,应用虎红平板凝集试验初筛,c ELISA复核确诊,对山区家畜布病监测控制净化具有重大     

牛种布鲁氏菌clpP基因缺失株的毒力和免疫保护力评价

为研究布鲁氏菌clpP基因与细菌毒力的关系,采用同源重组的方法,构建牛种布鲁氏菌clpP基因缺失株,用巨噬细胞RAW264.7感染模型和小鼠感染模型评价clpP基因缺失株的毒力,同时测定该缺失株免疫小鼠后产生的免疫保护力。研究发现:牛种布鲁氏菌clpP基因缺失后,在细胞感染模型和小鼠感染模型中的毒力显著降低;clpP基因缺失株感染小鼠后,不引起脾脏肿胀,并且在脾脏内的持续期短于A19疫苗株,说明该基因缺失株具有更高的安全性;使用clpP基因缺失株免疫小鼠后,该基因缺失株无法抵御牛种布鲁氏菌2308株和羊种布鲁氏菌M28株的感染。本研究为揭示布鲁氏菌致病机制和新型布病疫苗研发提供了参考。     

布鲁氏菌病及动物疫苗的研究进展

近年来,随着我国畜牧业的快速发展,布鲁氏菌病发病率有上升的趋势。借鉴已消除该病国家的防控和净化措施,疫苗的免疫预防是关键因素。除了传统的细菌培养疫苗牛种S19株、羊种Rev.1株、猪种S2株以及牛种RB51株,利用基因工程技术针对布鲁氏菌侵害机体的过程及其免疫抗原物质构建的新兴疫苗得到不断发展。笔者对布鲁氏菌的特点、危害、致病机制及动物疫苗应用进展进行介绍。     

布鲁氏菌病的临床诊断与防制

布鲁氏菌病简称布病．是由布鲁氏菌侵入机体引起的急性或慢性的人兽共患的传染病。布鲁氏菌是革兰氏阴性的短小杆菌．其毒力和致病力都很强，是细胞内寄生菌，其中羊种菌毒刀最强，猪种次之．牛种毒力较弱，以羊感染人的机会最多．目前已知有60多种驯兽动物、野生动物是该菌的宿主动。其传播途径很多，可经皮肤黏膜、消化道、呼吸道、交媾传播，也可通过结膜、吸血昆虫传播。     

From the discovery of the Malta fever's agent to the discovery of a marine mammal reservoir, brucellosis has continuously been a re-emerging zoonosis

Brucellosis is not a sustainable disease in humans. The source of human infection always resides in domestic or wild animal reservoirs. The routes of infection are multiple: food-borne, occupational or recreational, linked to travel and even to bioterrorism. New Brucella strains or species may emerge and existing Brucella species adapt to changing social, cultural, travel and agricultural environment. Brucella melitensis is the most important zoonotic agent, followed by Brucella abortus and Brucella suis. This correlates with the fact that worldwide, the control of bovine brucellosis (due to B. abortus) has been achieved to a greater extent than the control of sheep and goat brucellosis (due to B. melitensis), these latter species being the most important domestic animals in many developing countries. The long duration and high cost of treatment of human brucellosis reduces the efficacy of the therapy. There is no human vaccine for brucellosis and the occurrence of brucellosis is directly linked to the status of animal brucellosis in a region. In this context, the Word Health Organization has defined the development of a human vaccine, besides the implementation of control and eradication programs in animals, as a high priority. The pathogenicity for humans of B. suis biovars 1, 3 and 4 is well established, whereas B. suis biovar 2 seems to be less pathogenic. Indeed, although hunters and pig farmers have repeatably experienced infectious contact with B. suis biovar 2 (found in wild boar and outdoor-rearing pigs in Europe), isolation of B. suis biovar 2 from human samples have only been seldom reported. Marine mammal brucellosis, due to two new proposed Brucella species i.e. B. cetaceae and B. pinnipediae, represents a new zoonotic threat but the pathogenicity for humans of the different Brucella species found in cetaceans and pinnipeds still has to be clearly established.     

Role of catalase in the virulence of Brucella melitensis in pregnant goats

An isogenic katE mutant derived from virulent Brucella melitensis 16M displays hypersensitivity to hydrogen peroxide in disk sensitivity assays but retains the capacity to colonize pregnant goats and induce abortion. These experimental findings indicate that although the sole periplasmic catalase of Brucella melitensis functions as an antioxidant, this enzyme does not play a critical role in virulence in the natural host.     

布鲁氏菌病的研究进展

布病,尤其是由羊种布鲁氏菌引起的布病,目前是世界上最常见的一种人兽共患传染病,全世界每年报道的布病病例超过500万。布鲁氏菌已经被CDC列为B类病原体,成为潜在的生物武器。布鲁氏菌也是最常见的实验室源性病原体。布病的流行地域在不断变化,每年都有新发地和复发地的报道。除了那些牛布病已经根除的国家,布病仍然在许多国家的人和动物中存在。全世界由于布病给动物产品及公共卫生安全而带来的经济损失是巨大的。虽然许多有效的疫苗正在用于动物免疫,但是还没有理想的人用疫苗可以使用。动物布病的控制将显著降低人布病的发生。     

羊布鲁氏菌病及其国内外防控净化措施

布鲁氏菌病(简称"布病")是由布鲁氏菌引起的一种人兽共患传染病.在引起布病的所有布鲁氏菌中,对人和家畜威胁最大的是羊种布鲁氏菌.近年来我国针对布病防控颁布了《国家布鲁氏菌病防治计划(2016-2020年)》等相关文件,但布病尤其是羊布病的发生率仍然处于上升趋势.论文主要介绍国内常用的羊布病的防控方法和策略,并结合国外成...     

Brucella melitensis infection following military duty in Iraq

Brucellosis is a common zoonotic disease worldwide; however, few cases are reported in the US. Brucella melitensis infections are primarily acquired via consumption of high-risk foods or travel to endemic areas. We describe a case of B. melitensis infection in a Tennessee soldier following deployment in Iraq. Initial symptoms included knee and back pain. Culture of an aspirate of the left sacroiliac joint yielded B. melitensis. Genetic analysis indicated that this isolate came from the Middle East. Investigation of laboratory workers identified risky exposures and positive serology prompting post-exposure prophylaxis. Military personnel and other travellers should be advised to reduce risk regarding food consumption and animal contact in endemic areas. Additionally, medical providers should remain vigilant for non-endemic zoonoses among recent travellers.     

Brucella species lacking the major outer membrane protein Omp25 are attenuated in mice and protect against Brucella melitensis and Brucella ovis

To aid in the development of novel efficacious vaccines against brucellosis, Omp25 was examined as a potential candidate. To determine the role of Omp25 in virulence, mutants were created with Brucella abortus (BA25), Brucella melitensis (BM25), and Brucella ovis (BO25) which contain disruptions in the omp25 gene (Deltaomp25 mutants). Western immunoblot analysis and PCR verified that the Omp25 protein was not expressed and that the omp25 gene was disrupted in each strain. BALB/c mice infected with B. abortus BA25 or B. melitensis BM25 showed a significant decrease in mean CFU/spleen at 18 and 4 weeks post-infection, respectively, when compared to the virulent parental strain (P<0.05, n=5). Mice infected with B. ovis BO25 had significantly lower mean CFU/spleen counts from 1 to 8 weeks post-infection, at which point the mutant was cleared from the spleens (P<0.01, n=5). Murine vaccination with either BM25 or the current caprine vaccine B. melitensis strain Rev. 1 resulted in more than a 2log(10) reduction in bacterial load following challenge with virulent B. melitensis (P<0.01, n=5). Vaccination of mice with the B. ovis mutant resulted in clearance of the challenge strain and provided 2.5log(10) greater protection against virulent B. ovis than vaccine strain Rev. 1. Based on these data, the B. melitensis and B. ovis Deltaomp25 mutants are interesting vaccine candidates that are currently under study in our laboratory for their safety and efficacy in small ruminants.     

羊布鲁茵16MvjbR蛋白酵母双杂交诱饵表达载体的构建及其毒性和自激活效应检测

利用Sos招募系统（SRS）,通过聚合酶链反应（PCR）扩增羊布鲁菌16MVjbR基因的编码序列,定向克隆到酵母表达载体pSos中,构建诱饵重组质粒pSos－VjbR,经测序正确后其将转入酵母菌cdc25H（α）感受态细胞,检测其表达产物对酵母细胞有无毒性作用及对报告基因有无自激活作用。结果表明,经序列测定证实重组诱饵质粒pSos－VjbR构建成功。重组质粒转化入酵母细胞后,经检测其表达产物对cdc25H（α）酵母细胞无毒性作用,对报告基因亦无自激活作用。这为利用SRS来研究与羊布鲁菌16MVjbR蛋白相互作用的蛋白奠定了基础。     

Brucella melitensis 16M: characterisation of the galE gene and mouse immunisation studies with a galE deficient mutant

The galE gene of Streptomyces lividans was used to probe a cosmid library harbouring Brucella melitensis 16M DNA and the nucleotide sequence of a 2.5 kb ClaI fragment which hybridised was determined. An open reading frame encoding a predicted polypeptide with significant homology to UDP-galactose-4-epimerases of Brucella arbortus strain 2308 and other bacterial species was identified. DNA sequences flanking the B. melitensis galE gene shared no identity with other gal genes and, as for B. abortus, were located adjacent to a mazG homologue. A plasmid which encoded the B. melitensis galE open reading frame complemented a galE mutation in Salmonella typhimurium LB5010, as shown by the restoration of smooth lipopolysaccharide (LPS) biosynthesis, sensitivity to phage P22 infection and restoration of UDP-galactose-4-epimerase activity. The galE gene on the B. melitensis 16M chromosome was disrupted by insertional inactivation and these mutants lacked UDP-galactose-4-epimerase activity but no discernible differences in LPS structure between parent and the mutants were observed. One B. melitensis 16M galE mutant, Bm92, was assessed for virulence in CD-1 and BALB/c mice and displayed similar kinetics of invasion and persistence in tissues compared with the parent bacterial strain. CD-1 mice immunised with B. melitensis 16M galE were protected against B. melitensis 16M challenge.     

Brucella-induced abortions and infection in bottlenose dolphins (Tursiops truncatus).

Two bottlenose dolphins (Tursiops truncatus) aborted fetuses that died as a result of Brucella infection. Brucella placentitis occurred in both cases. Infected placenta and vaginal/uterine fluids may transmit Brucella species to other cetaceans. In a third case, an identical organism was cultured from lung necropsy tissue of an adult female T. truncatus. Microbiology, specific polymerase chain reaction, and pulsed-field gel electrophoresis results supported the designation of an additional genomic group(s), Brucella delphini, for isolates adapted to T. truncatus. Current serologic diagnostic tests reliable for known Brucella species are unreliable in detecting dolphin brucellosis. Our findings, together with previous reports, suggest that dolphin brucellosis is a naturally occurring disease that can adversely impact reproduction in cetaceans. The zoonotic significance of cetacean brucellosis is unknown, although the disease has not been reported in people who have frequent contact with dolphins. Further studies on the zoonotic aspects, distribution, prevalence, virulence, and impact of this disease in cetaceans and other marine mammal species are needed.     

布鲁氏菌表面抗原研究进展

布鲁氏菌表面最主要的抗原是脂多糖(LPS)和外膜蛋白(OMPs),R-LPS是R型布鲁氏菌主要的表面抗原,S型布鲁氏菌的S-LPS已被证明是一个主要的毒力因子,它的O链部分含有布鲁氏菌表面绝大多数的抗原位点,是一个很重要的保护性抗原;OMPs被认为是布鲁氏菌表面潜在的抗原结构,在光滑型布鲁氏菌表面,由于OMPs受到了LPS-O链的干扰,致使它的抗原性没有充分地表现出来,但在绵羊布鲁氏菌表面却出现了不同的情况。未来几年,对OMPs的研究将成为该领域的热点,尤其是对Omp25突变体的研究。