小反刍兽疫活疫苗的安全性评价试验

2007年小反刍兽疫(PPR)在我国西藏首次暴发,在西藏和新疆部分地区使用PPR Nigeria 75/1疫苗株制造的疫苗进行免疫接种。为明确疫苗的安全性,中国兽医药品监察所国家牛瘟参考实验室对其安全性能进行了系统评价。健康易感山羊、绵羊及怀孕山羊、怀孕绵羊按不同剂量接种疫苗后,均未观察到异常临床反应;怀孕母羊所产羔羊数量与对照组无明显差异。疫苗对小白鼠、豚鼠的非特异性安全试验表明,所有接种动物均健活。结果表明该疫苗安全性良好,可在田间大规模使用。     

小反刍兽疫活疫苗临床试验研究

通过观察免疫接种后动物的临床症状,采用中和试验法检测小反刍兽疫活疫苗(75/1株)免疫后3个月、15个月和26个月时免疫动物血清的抗体水平,评价和测定小反刍兽疫活疫苗在新疆和西藏地区临床应用的安全状况、免疫效果和免疫持续时间。结果显示,免疫动物未发现任何免疫接种引起的不良反应,表明疫苗对山羊和绵羊具有良好的安全性;免疫后3个月、15个月和26个月时,血清中和抗体阳性率分别为89.8%、93.6%和83.95%,表明该疫苗的免疫效力良好,免疫期至少可达26个月。     

小反刍兽疫疫苗研究进展

小反刍兽疫是由小反刍兽疫病毒引起的一种严重的烈性、接触性重大跨国动物疫病.目前,该病在我国已经发生,给我国畜牧业经济造成了巨大损失.同多数病毒性疾病的防制相同,对小反刍兽疫PPRS的防制仍以疫苗免疫预防为主.文章对小反刍兽疫的各类疫苗进行综述,以期为疫苗的合理应用提供技术帮助.     

小反刍兽疫研究进展

小反刍兽疫是由小反刍兽疫病毒引起的一种急性接触性传染病,又称羊瘟、伪牛瘟等.小反刍兽疫自发现起在非洲、中东以及亚洲大范围流行,为发展中国家的养羊业带来了巨大的灾难,也影响了这些国家的经济.FAO-OIE于2015年发布了《PPR全球控制和根除战略》,目标为到2030年在全世界范围内消除小反刍兽疫.文章就小反刍兽疫的发现...     

小反刍兽疫疫苗的研究进展

本文介绍了小反刍兽疫疫苗的最新研究情况,主要包括弱毒疫苗、灭活疫苗、重组亚单位疫苗、嵌合体疫苗、活载体疫苗及RNA干涉技术等。     

小反刍兽疫研究进展

小反刍兽疫(PPR)是由小反刍兽疫病毒(PPRV)引起的急性或亚急性传染病,为世界动物卫生组织(OIE)法定报告的动物疫病,易感动物以山羊、绵羊等小反刍动物为主。目前,小反刍兽疫主要流行于西非、中非、中东、阿拉伯半岛及南亚等地区。敏感特异的检测方法和高效的预防性疫苗将为该病的防控奠定良好的基础。论文对小反刍兽疫全球流行现状、诊断技术及疫苗研究进展进行了综述。     

小反刍兽疫研究进展

小反刍兽疫病毒(PPRV)是副黏病毒科(Paramyxoviridae)麻疹病毒属(Morbolivirus)的成员,主要感染山羊、绵羊等小反刍动物,引起一种高度接触性病毒性传染病。小反刍兽疫为一种重大的外来性疾病,2007年在中国西藏自治区日土县首次发生。自2013年末以来中国新疆、青海、甘肃、宁夏、内蒙、湖南、辽宁等地频繁暴发小反兽疫疫情,给中国的畜牧业带来了巨大的损失,引起极大的重视。为更好的分析小反刍兽疫的病原特性及采取有效的防控措施,文章对小反刍兽疫的病原学及疫苗研究进展进行论述。     

小反刍兽疫活疫苗二次免疫效果评价

为研究已免疫小反刍兽疫(PPR)活疫苗的羊群经二次免疫后PPR抗体水平的变化趋势,对初免21 d羊群进行了第二次免疫,同时监测初免21 d及二免后3 d、7 d、14 d、21 d的血清中和抗体。结果显示,一次免疫羊21 d PPR中和抗体滴度平均可达5.18±2.87,阳性率为84%;二次免疫后3 d、7 d、14 d、21 d,PPR抗体呈上升趋势,平均滴度分别为5.65±2.56、6.95±1.82、7.28±1.18、8.12±1.31,阳性率分别为90%、100%、100%、100%。一免试验组21 d~323 d PPR抗体阳性率为83%,二免试验组在二次免疫7 d PPR抗体阳性率达到100%,并且维持到21 d。试验表明,活疫苗二次免疫增强了免疫效果,对已经有PPR抗体的羊进行二次免疫,可明显提升免疫抗体阳性率。     

小反刍兽疫和山羊痘活疫苗联合免疫效果评价研究

试验旨在探索小反刍兽疫疫苗和羊痘疫苗相互之间免疫效果的影响,选择90只参试羊采用单独免疫小反刍兽疫疫苗和羊痘疫苗以及两种疫苗联合免疫方式,并于免疫前及免疫后第7、14、21、28、90、210 d采集血液样本,通过阻断ELISA和间接ELISA检测其抗体水平。结果显示,两种疫苗单独免疫的抗体合格率到免疫后210 d时均在75%以上,达到国家规定标准（70%）。两种疫苗联合分点免疫情况下,小反刍兽疫疫苗免疫效果比单独免疫效果好,其抗体阳性率在免疫后第7、14 d时极显著高于单独免疫（P<0.01）,21 d时显著高于单独免疫（P<0.05）;羊痘疫苗免疫效果比单独免疫效果较差,其抗体阳性率在免疫后第7、14、21 d时极显著低于单独免疫（P<0.01）,28 d时显著低于单独免疫（P<0.05）,到免疫后210 d时抗体合格率仅为63.3%,未达到国家标准。研究表明,羊痘疫苗与小反刍兽疫疫苗联合免疫时,羊痘疫苗可以促进小反刍兽疫疫苗的免疫效果,而小反刍兽疫疫苗却抑制了羊痘疫苗的免疫效果。     

小反刍兽疫的研究进展

概述了小反刍兽疫的易感动物、临床症状及病原的理化特征和基因组结构，重点阐述了病毒6种结构蛋白的大小和组成、小反刍兽疫病毒的分离培养、血清学及分子生物学诊断技术，并对其传统疫苗以及新型基因工程疫苗的研制进行了详细论述，以为该病的流行病学研究、诊断和免疫防制提供参考。     

小反刍兽疫免疫荧光诊断技术研究

为了建立小反刍兽疫(PPR)荧光抗体诊断方法,研究选用小反刍兽疫病毒(PPRV)Nigeria75/1减毒疫苗株制备抗原,免疫试验山羊,制备小反刍兽疫高免血清,用硫酸铵盐析法粗提免疫球蛋白(IgG),再应用提取的IgG制备异硫氰酸荧光素标记抗体。结果表明:所制备的荧光抗体对试验用Vero细胞组织抗原和犬瘟热病毒(CDV)抗原无反应性,对小反刍兽疫病毒感染细胞的检出敏感性为1×106稀释度。     

经密码子优化的小反刍兽疫病毒H蛋白在昆虫细胞中的表达

小反刍兽疫病毒（peste des petits ruminants virus,PPRV）属于副黏病毒科、麻疹病毒属成员。本实验室已经证明,该病毒的囊膜糖蛋白H蛋白在未经密码子优化条件下难以在昆虫细胞中表达。本研究首先对其密码子进行优化,然后构建了在昆虫细胞中表达该蛋白的重组杆状病毒。经Western-blot和间接免疫荧光试验表明,该重组杆状病毒在昆虫细胞中能够表达H蛋白,但表达量相对较低。     

Comparative nucleotide sequence analysis of the phosphoprotein gene of peste des petits ruminants vaccine virus of Indian origin

The nucleotide sequences of the phosphoprotein (P) gene of peste des petits ruminants (PPRV) vaccine virus (PPRV Sungri/96) belongs to Asian lineage have been determined and the deduced amino acid sequences were compared with another vaccine strain PPRV/Nigeria75/1 and with those of the other morbilliviruses. The 1652 nucleotides of the P gene encode a phosphoprotein of 509 amino acid residues (from nucleotide numbers 60 to 1587), which is 91% identical to that of PPRV/Nigeria75/1. The C protein consists of 177 amino acid residues and is 91% identical with that of PPRV/Nigeria75/1. The conserved mRNA editing site (5'TTAAAAGGGCACAG) was present at positions 742-756 in the P gene, which is conserved in all other morbilliviruses. The CTT trinucleotide sequence is present at the N/P and P/M intergenic region, which is totally conserved in morbilliviruses. This will be the third sequence for the P gene of PPRV since that of the vaccine strain and a wild-type Turkish isolate has been published already.     

Post vaccination and colostral peste des petits ruminants antibody dynamics in research flocks of Kirdi goats and Foulbe sheep of north Cameroon

We studied Kirdi goats and Foulbe sheep kept on-station at the Institute of Agricultural Research for Development (IRAD), Garoua to look at their immunological response following vaccination with a specific peste des petits ruminant (PPR) virus vaccine. Pre-vaccination PPR antibody seroprevalences were 44 and 29% in goats and sheep, respectively. Seroprevalences following vaccination were 100% in both species. Titres remained above the protection threshold level (1:10) in both species at 12 months. Maternal antibodies in young animals were detectable to up to 6 months of age but fell below the protection threshold level at 3.5 and 4.5 months in lambs and kids, respectively. Kids and lambs from immunised or exposed dams should be vaccinated at 4 and 5 months of age, respectively.     

Fine mapping and conservation analysis of linear B-cell epitopes of peste des petits ruminants virus nucleoprotein

Nucleoprotein (NP) is the most abundant and highly immunogenic protein of morbillivirus, and is presently the basis of most diagnostic assays for peste des petits ruminants virus (PPRV). In this study, fine epitope mapping and conservation analysis of linear B-cell epitopes on the PPRV NP has been undertaken using biosynthetic peptides. Nineteen linear B-cell epitopes were identified and their corresponding minimal motifs were located on the NP of PPRV China/Tibet/Geg/07-30. Conservation analysis indicated that ten of the 19 minimal motifs were conserved among 46 PPRV strains. Peptides containing the minimal motifs were recognized using anti-PPRV serum from a goat immunized with PPRV vaccine strain Nigeria 75/1. Identified epitopes and their motifs improve our understanding of the antigenic characteristics of PPRV NP and provide a basis for the development of epitope-based diagnostic assays.     

Seroprevalence of, and risk factors for, peste des petits ruminants in sheep and goats in Northern Jordan

Peste des petits ruminants (PPR) is an economically important disease that affect sheep and goat industry in Asia and Africa. In this study, we investigated the seroprevalence, and risk factors, of PPR in sheep and goat flocks from five different governorates (Irbid, Jarash, Ajloun, Mafraq and Zarka) located in Northern Jordan. Serum samples from 929 and 400 sheep and goats, respectively, corresponding to 122 sheep flock and 60 goats flock were collected. Seroprevalence was determined using PPR competitive ELISA. Health status and management information were collected using a semi-structured pre-tested questionnaire. The individual true prevalence of PPR in sheep and goats was 29 and 49%, respectively. The flock level true prevalence of PPR was 60 and 74% in sheep and goats, respectively. In both sheep and goat flocks, large flock size, visiting live animals market and inadequate veterinary services were identified as risk factors for PPR seropositivity. Mixed (sheep and goats) raising was identified as a risk factor for PPR seropositivity in sheep flocks only.