Effect of Vaccination with Brucella abortus Strain RB51 on Heifers and Pregnant Cattle

Thirteen cows, which had been vaccinated as calves with strain 19, were revaccinated twice or three times as adults with 1×10⁹ cfu of B. abortus strain RB51. Their serological responses following adult vaccination remained negative to conventional brucellosis surveillance tests. Vaccination with strain RB51 during the eighth month of pregnancy did not induce abortion, although strain RB51 was recovered from milk for up to 69 days after vaccination. In a parallel study, thirteen 8- to 10-month-old heifers were vaccinated as calves with 10⁹ cfu of strain RB51. The heifers remained seronegative to conventional brucellosis surveillance tests but antibody responses to RB51 could be demonstrated using an indirect ELISA. This study showed that multiple vaccination with strain RB51 did not induce seroconversion to brucellosis surveillance tests. In addition, this study suggests that 10⁹ cfu of strain RB51 is safe for use in pregnant cattle.     

Clinical and histological features of brucellin skin test responses in Brucella suis biovar 2 infected pigs

Current serological tests for swine brucellosis detect antibodies to the Brucella O-polysaccharide (O/PS). However, when infections by bacteria carrying cross-reacting O/PS occur, these tests suffer from false positive serological reactions (FPSR), and the skin test with Brucella soluble protein extracts is the best diagnostic alternative to differentiate true Brucella suis infections from FPSR in pigs. Since this test has been seldom used in B. suis infected swine, the clinical and histological features involved have not been described properly. Here, we describe the clinical and histological events in B. suis biovar 2 infected pigs skin tested with a cytosoluble O/PS free protein extract from rough Brucella abortus Tn5::per mutant. A similar extract from rough Ochrobactrum intermedium was also used for comparative purposes. No relevant differences were evidenced between the homologous and heterologous allergens, and the main clinical feature was an elevated area of the skin showing different induration degrees. Moreover, an important vascular reaction with hyperemia and haemorrhage was produced in most infected sows 24–48 h after inoculation, thus facilitating the clinical interpretation of positive reactions. Histologically, combined immediate (type III) and delayed (type IV) hypersensitivity reactions were identified as the most relevant feature of the inflammatory responses produced.     

上海地区输入性羊群传播布鲁氏菌病的定性风险评估

本研究按照OIE《陆生动物卫生法典》推荐的风险评估原则和步骤,对上海地区输入性羊群传播布鲁氏菌病开展危害识别、释放评估、暴露评估和后果评估,确定各类风险因素,对其风险等级进行描述和情景分析,并提出针对性的防控措施和建议,为政府部门制定管理政策提供科学依据和技术支持。     

绒山羊布氏杆菌病、衣原体和弓形虫病的血清学检测

采用布氏杆菌虎红平板凝集试验、弓形虫和衣原体间接血凝试验对360份绒山羊血清进行布氏杆菌病、弓形虫病和衣原体病的血清学调查。结果在绒山羊的血清样品中检出布氏杆菌病阳性血清8份,布氏杆菌病的血清阳性率为2．22％;检出弓形虫15份,弓形虫病血清阳性率为4．17％;检出衣原体23份,衣原体病血清阳性率为6．39％。     

一起放牧羊群布鲁氏菌病的分析检测

【目的】研究一起放牧羊群布鲁氏菌病(布病)分析检测方法适用性,为防治措施提供依据。【方法】采用RBT、GICA、SAT、MAT、FPA、iELISA、cELISA和PCR等方法检测90份来自流产羊群的血清样品,并从诊断方法的适用性特点、现场调查的结果进行统计分析。【结果】在90份羊血清样品中,RBT、GICA、SAT、MAT、FPA、iELISA、cELISA的阳性检出率分别为：8.89%(8/90)、12.22%(11/90)、17.78%(16/90)、14.44%(13/90)、21.11%(19/90)、25.56%(23/90)、24.44%(22/90),PCR检测出14份阳性。【结论】初筛可选用RBT、GICA、FPA或iELISA等方法,确诊选用SAT、MAT或cELISA等方法。放牧羊群布病阳性率随年龄增加呈上升趋势(成年羊42%>断奶羔羊2.5%);雌性羊布病阳性率高于雄性(雌性29.68%>雄性11.54%),有流产史的羊群患布病的风险更高,成年雌性羊更易感染布鲁氏菌。检出阳性羊进行无害化处理,羊舍和周围环境进行彻底消毒,使用布病M5-90弱毒疫苗对阴...     

动物布鲁氏菌Rev.1疫苗研究进展

布鲁氏菌病（布病）是由布鲁氏菌引起的一种重要的人畜共患病,对公共卫生有着巨大的威胁。布鲁氏菌Rev.1疫苗研制于上世纪50年代中期,并在欧洲、中东和蒙古等地区被广泛应用于小反刍动物布病的防控,一度被认为是防控小反刍动物布病最为有效的疫苗。但是,由于Rev.1疫苗存在毒力偏强及毒力不稳定等现象,其安全性仍值得关注。本文主要从Rev.1疫苗背景及其菌株的生物学特性、疫苗使用情况以及存在的不足等几个方面进行阐述,以期为Rev.1疫苗的应用和布鲁氏菌相关疫苗的开发提供借鉴。     

贵州省家畜布氏杆菌病血清学检测

为了解贵州省各地区布氏杆菌病流行情况,采用试管凝集试验对部分地区牛血清(706份)、羊血清(180份)、猪血清(720份)共计1606份进行了试验检测.结果表明:牛阳性血清7份,阳性率0.99%(7/706);羊阳性血清2份,阳性率1.11%(2/180);猪阳性血清3份,阳性率0.42%(3/720).贵州部分地区存在布氏杆菌病感染的可能.     

布鲁氏菌病的流行及防控研究概况

布鲁氏菌病是一种人畜共患病,作者对布病的流行概况进行了分析总结,并介绍了目前布氏杆菌的主要分离、诊断和防制措施进展。     

布氏杆菌病诊断技术研究进展

布氏杆菌病(brucellosis)是由布氏杆菌(Brucella)感染引起的以流产、生殖器官炎症、关节炎为主要症状的慢性人兽共患病,主要危害人和动物的生殖健康,侵害多个组织器官,不易治愈,我国将其列为二类动物传染病。近年来,我国各省份报告病例呈上升趋势,防控形势日益严峻,而及时准确地诊断对预防和控制布氏杆菌病具有极其重要的作用。本文从布氏杆菌病的流行病学、临床特征、细菌学诊断、血清学诊断、分子生物学诊断、分子分型技术等方面的研究进展进行综述,以期为该病的诊断提供参考。     

两起人布鲁氏菌病疫情相关的畜间流行病学调查和处置

2021年3—4月,湖南省冷水江市和新化县分别发生一起人布鲁氏菌病疫情。为及时获得疫情发生发展情况,确定疫情来源,科学处置疫情,阻断传播风险,通过现场走访问询、实验室检测等方式开展了畜间疫情调查。结果显示:两例人布鲁氏菌病病例均为山羊养殖从业者,其养殖羊群的布鲁氏菌抗体阳性率分别为44.4%和15.4%;从外地引进未经检疫山羊混群饲养是疫情发生的主要原因,缺乏有效的流通监管和共同放牧导致疫情扩散。根据调查结果,当地畜牧兽医部门按相关规定对发病羊群及流行病学关联羊群进行了扑杀和无害化处理,使疫情得到有效控制。本次疫情提示,养殖者应提升防疫主体责任和自身防护意识,规范引种和调运,隔离饲养,相关部门应严格产地检疫和流通监管,强化监测预警,积极开展布鲁氏菌病防治知识宣传和净化工作。