牛传染性鼻气管炎弱毒疫苗免疫抗体水平与保护效力的关系

利用微量血清中和试验和攻毒试验、牛传染性鼻气管炎弱毒活疫苗检测免疫后牛血清中牛传染性鼻气管炎病毒的抗体效价及其与保护效力的平衡关系。40头牛其中弱毒活疫苗免疫牛30头,对照牛（抗体阴性牛）10头,采用不同剂量免疫（10^3.5～10^6.5TCID50／mL）,按抗体效价高低将实验动物分,并用IBRV LN01／08强毒株攻击,将攻毒保护结果与攻毒时抗体效价结果平行比较分析,结果显示,当IBRV抗体效价高于1：6时,疫苗免疫可以对牛产生良好的保护效力,保护率在80％以上,低于1：6但高于1：3时,免疫苗抗体阳性牛攻毒后保护率近78％。试验结果显示牛传染性鼻气管炎活疫苗的抗体水平于保护效力之间存在一定的平行关系。     

牛传染性鼻气管炎病毒LNM株致弱疫苗免疫效力的研究

为检测牛传染性鼻气管炎病毒(IBRV)抗体在免疫牛体内的产生及其消长规律,评价IBRV LNM株致弱疫苗的保护效力,并确定免疫持续期,本实验对免疫试验组牛每头颈部肌肉接种制备的IBRV LNM株致弱疫苗104.5 TCID50/mL,监测血清抗体效价,进行免疫期的确定。在疫苗免疫后的6个月、9个月和12个月分别抽取3头免疫组和两头对照组牛采用IBRV-LN01/08强毒株进行攻毒试验,每头牛的攻毒剂量为107.0 TCID50/mL。结果显示疫苗免疫后12个月时,中和抗体效价仍维持在1∶11以上。攻毒结果显示3个时间点强毒攻击后,疫苗对免疫牛均具有良好的保护力。研究表明IBRV弱毒疫苗可有效地保护免疫牛抵抗IBRV强毒株的攻毒,其免疫持续期最少为12个月。     

牛传染性鼻气管炎弱毒与牛病毒性腹泻弱毒抗原免疫干扰的研究

本试验使用3~6月龄健康易感牛9头(牛传染性鼻气管炎病毒(IBRV)和牛病毒性腹泻病毒(BVDV)抗原、抗体均阴性),共分3组,每组3头犊牛。第1组首免肌肉注射IBRV-LNM弱毒疫苗株种毒,接种1周后,每头牛接种BVDV-SM弱毒疫苗株;第2组只接种BVDV-SM弱毒疫苗株种毒,接种时间同第1组;第3组为对照组,接种MDBK细胞培养液。接种BVDV-SM疫苗毒后每周采血至疫苗毒接种后28 d,测定接种后BVDV抗体效价,并采用BVDV-JL检验用强毒进行攻毒试验。结果表明,第1组与第2组试验动物血清中牛病毒性腹泻病毒抗体水平无明显差异,能够抵抗BVDV-JL强毒攻击达到免疫保护的效果,说明牛传染性鼻气管炎病毒IBRV-LNM弱毒疫苗株接种后在牛体内对牛病毒性腹泻病毒BVDV-SM疫苗毒不产生免疫干扰作用。     

牛传染性鼻气管炎病毒的分离鉴定与灭活疫苗免疫效果研究

由2例疑似牛传染性鼻气管炎（IBR）病例的荷斯坦奶牛分离到一株病毒,命名为IBRV—C1株。该病毒可被IBR标准阳性血清完全中和;接种MDBK细胞可出现IBR病毒典型细胞病变效应;选取IBR病毒gB蛋白基因序列设计引物进行PCR检测和基因测序,结果可扩增出特异性目的片段;动物回归试验显示,3头牛均可见体温升高、鼻流粘液、呼吸困难等典型的IBR临床症状。在此基础上制备了三批牛传染性鼻气管炎灭活疫苗,并进行了疫苗安全性和效力试验,结果表明三批疫苗对靶动物安全,免疫效果较好,免疫牛中和抗体效价几何平均值可达1：41以上,攻毒保护率达5／5。     

牛传染性鼻气管炎病毒JZ06-8株犊牛感染模型的建立

为建立IBRV对犊牛的感染模型,将试验组第1组~3组犊牛通过鼻腔内喷雾接种4mL/头,病毒含量分别为107.0 TCID50/mL、106.0 TCID50/mL和105.0 TCID50/mL的IBRV/JZ06-8,阴性对照组同样方法接种MDBK细胞冻融物;攻毒后第0天~第14天,每天测定直肠温度,进行临床观察,采集鼻拭子进行病毒分离鉴定。结果显示,鼻内喷雾接种对犊牛可产生有效感染,106.0 TCID50/mL的感染剂量即可致犊牛产生典型的IBR临床症状,并可分离到IBRV。试验成功实现IBRV/JZ06-8对犊牛的感染,该模型可用于IBRV研究和IBR疫苗评价。     

牛传染性鼻气管炎疫苗的研究进展

牛传染性鼻气管炎(infectious bovine rhinotracheitis,IBR)是由牛传染性鼻气管炎病毒(infectious bovine rhinotracheitis virus,IBRV)即牛疱疹病毒1型(BoHV-1)感染所引起的一种高度接触性传染病。该病给我国养牛业带来了巨大的经济损失。由于缺乏有效的治疗性药物,疫苗免疫仍然是防控该病的有效措施。当前,牛传染性鼻气管炎疫苗主要包括灭活疫苗、弱毒疫苗2种常规疫苗和亚单位疫苗、DNA疫苗、IBRV基因缺失疫苗、病毒活载体疫苗4种基因工程疫苗,各种疫苗各有优点。现对上述疫苗的最新研究进展进行综述,以期为IBRV疫苗的研究与开发提供参考。     

新疆某规模化奶牛场牛传染性鼻气管炎病毒抗体水平检测

为了调查新疆地区某规模化奶牛场牛传染性鼻气管炎（IBR）发病情况,通过采集不同生长阶段牛群血清共计362 份,使用牛传染性鼻气管炎病毒gB（IBR-gB）抗体检测试剂盒检测牛传染性鼻气管炎病毒（IBRV）抗体效价,评估该奶牛场IBRV疫苗免疫效果。结果显示,后备牛中犊牛和青年牛IBRV抗体阳性率分别为88.57%（31/35）、75.00%（21/28）;成年母牛中泌乳期母牛、干奶期母牛IBRV抗体阳性率分别为81.46%（145/178）、95.04%（115/121）。阴性数共44 份,可疑数8 份,IBRV抗体平均阳性率为88.38%;结果表明,疫苗接种后,不同生产阶段牛群均可产生不错的抗体保护效果,为奶牛场防控IBR提供依据。     

牛传染性鼻气管炎病毒LN01/08株灭活疫苗的研制

为研制牛传染性鼻气管炎病毒(IBRV)灭活疫苗,本研究以国内分离鉴定的IBRV LN01/08株为种毒,优化病毒增殖条件,获得病毒滴度达108.0TCID50/mL,将其灭活制备疫苗.为比较不同免疫佐剂的效果,分别以矿物质白油和Montanide ISA206佐剂配制灭活疫苗,进行牛体免疫试验.临床观察和血清中和抗体检测结果表明,Montanide ISA206佐剂乳化的疫苗在降低副反应和增强免疫效果方面优于矿物质白油佐剂.应用Montanide ISA206佐剂制备3批灭活疫苗,并对其安全性和免疫保护效果进行测定.结果表明该疫苗安全可靠,对强毒攻击可产生较好的抵抗力,攻毒保护率达80%.疫苗在2℃～8℃保存12个月后仍能保持良好的免疫效果.     

牛传染性鼻气管炎检测方法的研究进展

牛传染性鼻气管炎病毒(IBRV)是引起牛传染性鼻气管炎的病原。文中介绍了牛传染性鼻气管炎的各种检测方法的研究进展,包括病理组织学诊断、病毒的分离鉴定、免疫学检测和核酸分子检测,为牛传染性鼻气管炎的检测提供了有价值的参考。     

IBRV感染对牛单核巨噬细胞产生一氧化氮(NO)的影响

为探讨牛传染性鼻气管炎病毒(IBRV)感染牛单核巨噬细胞后的免疫机理,采用Ficoll-Hypaque密度梯度离心法分离牛外周血单个核细胞,再经贴壁培养获得单核巨噬细胞。应用Griess法检测接种IBRV后6、12、24、48h时间段的牛单核巨噬细胞分泌一氧化氮(NO)的含量,结果显示,单核巨噬细胞感染IBRV后产生NO的量均高于对照组(P<0.05),攻毒24h时巨噬细胞产生NO的量达到最高水平(607.87μmol/L)。结果表明,IBRV感染可以对单核巨噬细胞分泌NO的量产生影响,这可能和IBRV引起的致病机理有一定关系。     

Efficacy of viral components of a nonabortigenic combination vaccine for prevention of respiratory and reproductive system diseases in cattle

Efficacy and safety of components of an IM-administered vaccine for prevention of infectious bovine rhinotracheitis virus (IBRV), parainfluenza type-3 (PI-3) virus, bovine viral diarrhea virus (BVDV), and respiratory syncytial virus (RSV) infections and campylobacteriosis and leptospirosis were evaluated in cattle, including calves and pregnant cows. Challenge of immunity tests were conducted in calves for IBRV, PI-3 virus, or BVDV vaccinal components. All inoculated calves developed serum-neutralizing antibodies and had substantially greater protection (as measured by clinical rating systems) than did controls after challenge exposure to virulent strains of IBRV, PI-3 virus, BVDV, or RSV. In in utero tests, IBRV or bovine RSV vaccinal strains were inoculated into fetuses of pregnant cows. Histologic changes or abortions did not occur after fetal inoculation of the RSV vaccinal strain, and 10 of 14 fetuses responded serologically. Of 9 fetuses, one responded serologically to the IBRV vaccinal strain after in utero inoculation and was aborted 3 weeks later. In an immunologic interference test, 10 calves vaccinated with 2 doses of the multivalent vaccine, containing the 4 viral components and a Campylobacter-Leptospira bacterin, developed serum-neutralizing antibodies to IBRV, PI-3 virus, BVDV, and RSV without evidence of serologic interference. Under field conditions, 10,771 cattle, including 4,543 pregnant cows, were vaccinated. Vaccine-related abortions did not occur.     

Transmission of a vaccinal strain of infectious bovine rhinotracheitis virus from intranasally vaccinated steers commingled with nonvaccinated steers

Ninety-seven feeder steers, averaging 7 months of age, were allotted to 3 groups. Group I (n = 33) was vaccinated intranasally with an infectious bovine rhinotracheitis virus (IBRV) vaccine on postinoculation day (PID) 0; group II (n = 31) was not vaccinated on PID 0 but was commingled with group I; and group III (n = 33) served as controls housed in the same facility, but was physically separated from groups I and II. On PID 20, all steers were given a modified-live IBRV vaccine IM. Virus isolation attempts from nasal swab specimens collected on PID 10 resulted in IBRV isolation from 19 (57.6%) of group I, 4 (12.9%) of group II, and 0 of group III. By PID 20, geometric mean titer for serum antibody to IBRV had increased in group I but had decreased in groups II and III. By PID 40, geometric mean titer for serum antibody to IBRV had increased in the 3 groups in response to IM vaccination given on PID 20. Seemingly, transmission of a vaccinal strain of IBRV to nonvaccinated steers did not take place at a frequency that elicited a humoral immune response similar to that of vaccinated steers.     

Cell-mediated immunity in calves immunized against or infected with the bovine rhinotracheitis virus

Simple and expeditious methods--leucocyte adherence inhibition LAI and leucocyte migration inhibition LMI--are described in the present paper; these methods enable to investigate cell-mediated immunity of animals. The two tests, along with serological and virological methods, were used to study changes in the immunity of calves after experimental infection by IBRV and after immunization by inactivated oil vaccine against IBRV. The results have indicated that the changes in cell-mediated immunity after experimental infection and vaccination of calves assumed courses independent of the changes in humoral reaction. Total cell-mediated immunity reaction started earlier in experimentally infected calves than in vaccinated ones. In some vaccinated calves a modified course of cellular immunity reactions was observed, characterized also by elimination of IBR virus on the nasal mucous membrane after challenge infection. The LAI and LMI test can be recommended for immunological monitoring in clinical laboratories and in research.     

传染性牛鼻气管炎病毒分离鉴定及特性分析

传染性牛鼻气管炎病毒(infectious bovine rhinotracheitis virus,IBRV)是牛的重要传染病病原,除能引起呼吸道疾病外,还可引起结膜炎、流产、脑炎和全身性感染。本试验从广东某牛场疑似IBRV感染牛中采取鼻拭子样品,用PCR和荧光PCR方法,初步诊断病牛感染IBRV。用MDBK细胞对初诊阳性病料进行病毒分离和鉴定,分离出1株传染性牛鼻气管炎病毒,命名为GD0109。细胞感染试验表明,该株病毒可以使MDBK细胞产生典型的圆缩、呈葡萄样聚集以及空洞等细胞病变。将GD0109与强毒的ATCCVR-2112TM株感染细胞裂解液分别接种MDBK细胞并盲传5代,对5代、10代、15代的病毒分别进行TCID50测定及中和试验,结果表明分离株和参考株VR-2112TM相似,提示该分离株为强毒株,并且具有良好的传代稳定性,为进一步疫苗生产打下良好的基础。     

河南孟津地区6种引起奶牛流产病原的PCR检测及分析

为调查孟津地区引起奶牛流产的主要病原,本实验采集该地区8个规模化奶牛养殖场共52头新鲜流产胎牛,及其母体的血液、阴道分泌物和鼻腔分泌物。对所采集样本进行新孢子虫（N.caninum）、弓形虫(T.gondii)、胎儿三毛滴虫(T. foetus)、布氏杆菌(B.abortus)、牛传染性鼻气管炎病毒（IBRV）和牛病毒性腹泻病毒（BVDV）6种常见流产病原的PCR和RT-PCR检测。结果显示,被检样本总感染率为44.2%（23/52）,其中新孢子虫感染率最高,为32.7%（17/52）;IBRV次之,为13.5%（7/52）;胎儿三毛滴虫、布氏杆菌、弓形虫和BVDV感染率分别为1.9%、1.9%、1.9%和0。11.5%（6/52）的被检样本存在混合感染,其中以新孢子虫+IBRV混合感染为主（50%,3/6）。结合被检流产奶牛的临床特征及饲养管理等因素,推断新孢子虫是导致该地区奶牛流产的主要病原。     

1株牛传染性鼻气管炎病毒的分离鉴定

在对进口种用奶牛隔离检疫期间,从1头IBRV中和抗体阳性奶牛中分离出1株病毒。该分离株表现类似于IBRV特征的细胞病变,细胞圆缩,聚集成葡萄串样群落,在单层细胞上形成空洞。用特异性抗IBRV阳性血清与其进行中和试验,发现IBRV标准阳性血清对分离株的中和抗体滴度为27,与IBRV标准株的中和抗体滴度相差不到1个滴度。用OIEV推荐的IBR特异性引物对分离病毒进行PCR扩增,获得与设计基因片段大小一致的特异性条带,表明分离到的病毒为IBRV。