猪瘟疫苗及“猪三联苗”的正确使用

猪瘟疫苗及“猪三联苗”是在我国养猪生产中使用最多和数量最大的疫苗，但我们发现在不少地方使用这些疫苗后仍然免疫效果不好，甚至免疫失败，其主要原因是对疫病和疫苗的特点及其性能认识不足甚或误识，再者是使用技术失误，为保证免疫效果，现就其关键技术做如下叙述，以供在生产实践中应用。     

猪瘟疫苗及猪三联苗的合理使用

猪瘟是猪的一种严重传染病,对养猪业的危害非常巨大,因此在每年的春、秋两季防疫中,猪瘟被列为首防的疫病。目前,我们使用的疫苗主要有猪瘟活疫苗（Ⅱ）和猪三联苗（猪瘟、猪丹毒、猪肺疫三联活疫苗）,均为“中牧”公司生产。猪三联苗可以同时预防对应的三种疫病,节约时问,因此很多防疫员喜欢使用。现就如何合理使用猪瘟疫苗及猪三联苗谈一点肤浅的看法。     

猪瘟疫苗和猪三联疫苗的科学应用

在养猪生产中，猪瘟疫苗、猪三联疫苗是使用率最高、数量最大的疫苗，但在不少地方使用疫苗后，免疫效果仍不理想，甚至出现免疫失败或免疫时间达不到要求的现象，其主要原因是对疫病和疫苗的特点及其性能认识不足或操作不规范等原因造成的。为此笔者特将多年来的实践经验总结如下，以供广大读者今后在实践中参考应用。     

正确认识和使用猪瘟疫苗及"猪三联苗"

猪瘟(Hogcholera，HC)是猪的一种严重传染病，它对全世界的养猪业构成巨大威胁。我国目前发生的猪病中，仍以猪瘟流行最广、发病最多、危害最大。近些年，因猪瘟而死亡的猪数约占我国病猪死亡总数的1／3。我国应用猪瘟兔化弱毒株疫苗对猪进行免疫已近50年，虽然取得了显著成效，但猪瘟的危     

猪蓝耳病疫苗与猪三联苗、二联苗免疫效果影响的研究分析

自生猪"高热病"暴发后,国家将猪蓝耳病列为强制免疫的疫病,以确保我省生猪养殖业的健康发展。但是,高致病性猪蓝耳病疫苗对现在我市实用广泛的猪三联苗、二联苗是否存在免疫拮抗,目前没有明确的试验数据报道。本试验旨在研究猪蓝耳病疫苗对猪三联苗、二联苗免疫效果的影响。     

注射猪三联苗引发猪瘟的原因浅析

近年来西宁市猪瘟时有发生，出现严重势头，而且发病猪大都接种过疫苗。本文就西宁市猪瘟发生和引起原因进行分析。     

给猪免疫使用疫苗的几项关键技术

给猪进行疫苗接种以预防猪传染病的发生，已成为养猪生产者所必不可少的工作内容，但免疫效果往往要涉及到许多相关问题，如疫苗的种类和质量，猪机体本身的应答，外界影响因素，疫苗的使用技术以及许多与免疫程序制定等有关的问题，都会严重影响免疫效果，现仅对在疫苗使用中几项易被忽略或认识不清的关键技术做一简要叙述。     

应用猪三联苗免疫后仍暴发猪瘟的报告

猪瘟,猪丹毒、猪肺疫三联苗(以下简称三联苗)已在全国大多数地区推广应用,但近年来有部分猪场在应用三联苗免疫后仍暴发典型猪瘟病例,报告如下.     

猪瘟疫苗的选择及使用注意事项

<正>笔者从事兽医临床几十年,总结了多年来使用猪瘟细胞苗的经验、教训和体会现进行整理,与广大兽医界同仁交流与商榷。1要使用猪瘟兔化弱毒单苗猪瘟疫苗包括猪瘟兔化弱毒犊牛睾丸     

A promising multiple-epitope recombinant vaccine against classical swine fever virus

Classical swine fever (CSF) is a highly contagious and often fatal disease of swine. It is caused by classical swine fever virus (CSFV), one of the members of the genus Pestivirus of the Flaviviridae family. The development of a safe and effective vaccine against the CSF is critical to pandemic control, this article shows a tandem-repeat multiple-epitope recombinant vaccine can protect pigs from CSFV challenge. That was composed as following: two copies each of glycoprotein E2 residues 693–707, 241–276 and 770–781, and two copies amino acid residues 1446–1460 of the non-structural protein NS2-3. In the challenge test, all of the swine vaccinated with Chinese vaccine strain (C-strain) were fully protected from a challenge with CSFV. However, after three successive vaccinations with the multiple-epitope recombinant vaccine, three out of five pigs were protected from challenge with CSFV (in terms of both clinical signs and viremia). These results demonstrate that multiple-epitope recombinant vaccine which carrying the major CSFV epitopes can induce a high level of epitope-specific antibodies and exhibit a protective capability that parallels induced by C-strain to a certain extent.     

Swine fever: classical swine fever and African swine fever.

Because of the clinical and pathologic similarity to common endemic diseases, introduction of CSFV or ASFV strains of moderate to low virulence represents the greatest risk to North American swine herds. Producers, veterinarians, and diagnosticians should increase their awareness of these devastating diseases and request specific diagnostic testing whenever they are suspected. Production practices that improve biosecurity will reduce the risk of introduction of CSF and ASF and limit the spread if an incursion occurs. Additional resources. The following Web sites contain excellent color photographs that will assist producers and practitioners in identifying clinical signs and gross lesions associated with CSFV and ASFV: http://www.vet.uga.edu/vpp/gray_book/FAD and http://www.pighealth.com. The latter Web site and the OIE Web site (http://www.oie.int) offer updated information on current worldwide epizootics of ASF and CSF and other swine diseases. Details of biosecurity procedures can be found at http://www.agebb.missouri.edu; see publication G2340.     

非典型猪瘟

猪瘟是一种致死率高、危害严重的急性传染病 ,受到各养猪国家的关注。我国对猪瘟的防制工作十分重视 ,并提出当前应采取以免疫接种为重点的综合性防制措施。近年来典型猪瘟显然不多见了 ,但在一些地区和猪场却出现了一种非典型猪瘟。由于其缺乏猪瘟的典型症状和病变 ,易被人们误诊 ,以至滥用药物 ,盲目治疗 ,既增加了药费的支出 ,又贻误了防制时机 ,给猪场带来更大的经济损失。本文就非典型猪瘟的临床诊断、病因分析和防制措施等问题 ,作简要的介绍和探讨。1　非典型猪瘟的表现形式1 1　繁殖障碍型猪瘟主要发生于生产母猪 ,其本身呈隐性感染…     

猪瘟疫苗研究进展及我国传统疫苗的研究现状

简要介绍了国内外传统猪瘟疫苗和新型猪瘟疫苗的研究进展,着重对我国猪瘟传统疫苗的特点、生产工艺、生产和应用中的问题进行了概述,并对猪瘟疫苗研究做了展望.     

Development of a classical swine fever subunit marker vaccine and companion diagnostic test

The development of a classical swine fever (CSF) subunit marker vaccine, based on viral envelope glycoprotein E2, and a companion diagnostic test, based on a second viral envelope glycoprotein E(RNS), will be described. Important properties of the vaccine, such as onset and duration of immunity, and prevention of horizontal and vertical transmission of virus were evaluated. A single dose of the vaccine protected pigs against clinical signs of CSF, following intranasal challenge with 100LD(50) of virulent classical swine fever virus (CSFV) at 2 weeks after vaccination. However, challenge virus transmission to unvaccinated sentinels was not always completely inhibited at this time point. From 3 weeks up to 6 months after vaccination, pigs were protected against clinical signs of CSF, and no longer transmitted challenge virus to unvaccinated sentinels. In contrast, unvaccinated control pigs died within 2 weeks after challenge. We also evaluated transmission of challenge virus in a setup enabling determination of the reproduction ratio (R value) of the virus. In such an experiment, transmission of challenge virus is determined in a fully vaccinated population at different time points after vaccination. Pigs challenged at 1 week after immunization died of CSF, whereas the vaccinated sentinels became infected, seroconverted for E(RNS) antibodies, but survived. At 2 weeks after vaccination, the challenged pigs seroconverted for E(RNS) antibodies, but none of the vaccinated sentinels did. Thus, at 1 week after vaccination, R1, and at 2 weeks, R=0, implying no control or control of an outbreak, respectively. Vertical transmission of CSFV to the immune-incompetent fetus may lead to the birth of highly viraemic, persistently infected piglets which are one of the major sources of virus spread. Protection against transplacental transmission of CSFV in vaccinated sows was, therefore, tested in once and twice vaccinated sows. Only one out of nine once-vaccinated sows transmitted challenge virus to the fetus, whereas none of the nine twice-vaccinated sows did. Finally, our data show that the E(RNS) test detects CSFV-specific antibodies in vaccinated or unvaccinated pigs as early as 14 days after infection with a virulent CSF strain. This indicates that the E2 vaccine and companion test fully comply with the marker vaccine concept. This concept implies the possibility of detecting infected animals within a vaccinated population.     

猪瘟疫苗中牛病毒性腹泻病毒2型的检测

为对上海某猪场送检的一份猪瘟疫苗进行牛病毒性腹泻病毒(BVDV)检测,本研究将猪瘟疫苗样品接种于MDBK细胞,盲传15代后仍无致细胞病变效应,但间接免疫荧光试验表明接种该疫苗后的MDBK细胞能够被单克隆抗体BZ-53(BVDV-2)识别。采用BVDV-1和BVDV-2的5’-UTR的通用检测引物和针对BVDV E2的引物,对样品RNA进行RT-PCR检测,结果显示,样品能够扩增出约288 bp的BVDV特异性片段;此外,5’-UTR和E2基因片段的测序分析结果表明分离株属于BVDV-2,并且其E2基因与牛源XJ-04株(BVDV-2)的E2基因同源性最高(92.3%),而与猪源ZM-95株(BVDV-1)的E2基因同源性较低(64.5%)。由此证明,该猪瘟疫苗中的确污染有一株BVDV-2株。     

猪瘟疫苗的豚鼠变态反应试验

本研究用猪瘟疫苗初次致敏豚鼠未引起异常反应,两周后进行第2次激发可见明显的异常反应,甚至死亡,这证明了猪瘟疫苗可能引起变态反应的发生。为了找到疫苗中的真正过敏原,本研究进行了疫苗中主要成分的分组试验,结果表明犊牛血清的致敏作用最强,其次为猪瘟病毒,牛睾丸细胞最弱。同时进行了4种致敏和激发途经的比较实验,并用ELISA法测定了致敏和激发后血清中的IgE水平。结果表明各种致敏途径均可致敏,但激发时,以静脉注射最为严重,且致敏后和激发后均未检测到血清中的IgE水平有显著提高。     

The influence of maternal immunity on the efficacy of a classical swine fever vaccine against classical swine fever virus,genogroup 2.2, infection

In Thailand, where vaccination is routinely employed, there has been an increased incidence of chronic classical swine fever (CSF) outbreaks during the past decade. The major causative virus has been identified to be the moderate virulence, classical swine fever virus (CSFV) of the genogroup 2.2. An investigation was made into the efficacy of a CSF vaccine against this genogroup 2.2 challenge. Five-week-old pigs, grouped by their level of passive antibody titer were immunized with lapinized Chinese-strain CSF vaccine and challenged with CSFV genogroup 2.2, 13 days after vaccination. The group containing passive titers of lower than 64 at the time of immunization, had significantly higher number of CSFV-specific IFN-gamma secreting cells and was completely protected against the challenge. Interestingly, both cellular and antibody responses were inhibited in the pigs with the higher passive titer. Furthermore, following challenge, CSFV could be isolated from 50% of the pigs in this group. It was demonstrated that the CSF vaccine could induce complete protection in pigs, provided that the maternal derived titer at the time of vaccination was lower than 64. The result implied that an increase in CSFV outbreaks might be due to the inappropriate timing of vaccination as well as the nature of the CSFV genogroup 2.2.     

猪瘟病毒野毒株RT-LAMP可视化检测方法的建立

本研究旨在建立一种可视化检测猪瘟病毒(CSFV)野毒株的反转录.环介导等温扩增方法(RT-LAMP).根据CSFV的NS5B基因序列设计一套RT-LAMP引物,以样品的cDNA为模板,利用Bsf DNA聚合酶,在62℃恒温条件下进行扩增,扩增产物中加入sYBR Green I染料直接或在紫外光下观察判定扩增结果.该方法可检测出不同基因型的CSFV厂野毒株,其检出极限为2.5 TCID_(50)的CSFV,与实时荧光定量RT.PCR方法的敏感性相当;特异性试验表明,该方法对猪瘟免化弱毒疫苗株(HCLV)、牛病毒性腹泻病毒以及其它常见猪源病毒均无扩增反应;通过对126份不同样品进行检测比较,该方法与实时荧光定量RT-LAMP检测方法的符合率达100%.与引物.探针能量转移PCR方法的符合率为98.4%.该方法无需特殊仪器,是一种适用于基层的快速、简便的CSFV野毒鉴别检测方法.     

泉州市洛江区猪瘟抗体水平检测效果分析

结合实验室每年的检测工作,2013-2014年对洛江区辖区内20个生猪规模养殖场和89个散养户的856份猪血清进行猪瘟疫苗免疫抗体检测。结果表明:洛江区猪瘟疫苗免疫抗体合格率呈现上升趋势,规模场猪瘟疫苗免疫抗体合格率明显高于散养户,免疫2次的抗体合格率明显高于1次。抗体检测工作的开展,对制定科学合理的免疫程序,有效防控猪瘟疫情的发生发挥了积极的作用。