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免疫接种是预防和控制畜禽传染病的主要技术措施,畜禽免疫失败就是畜禽虽然已接种了某种疫苗,但在规定的免疫期内仍发生这种传染病或抗体监测时达不到应有的抗体水平。引起免疫失败的原因有很多,现简要归纳如下:1母源抗体影响母源抗体水平较高时会抑制疫苗的免疫反应,使雏鸡或仔猪首免失败。目前认为,鸡新城疫、鸡传染性法氏囊病、鸡马立克氏病、猪瘟等疫苗的接种都会因为母源抗体而影响其免疫效果。2疫苗因素2.1选用疫苗不当较常见的是使用的毒型与本地流行的毒型不一致,达不到免疫的目的。如传染性法氏囊病疫区,用弱毒力的疫苗给7日龄以内… 相似文献
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猪瘟灭活疫苗抗体消长规律动态分析 总被引：2，自引：0，他引：2
猪瘟(CSF)是由猪瘟病毒(CSFV)引起的一种猪的急性、烈性传染病,被国际兽疫局(OIE)列为A类传染病。我国每年都投入大量的人力、物力、财力进行猪瘟疫病的研究及控制工作。但近年来猪瘟仍有发生,且有增强的趋势。至今尚无特效的治疗药物,疫苗预防仍是我国防治猪瘟的主要手段。通过对母源抗体跟踪监测和对猪瘟灭活疫苗不同免疫剂量和不同首免日龄进行比较试验,系统地反映了猪瘟母源抗体及灭活疫苗免疫后抗体的消长规律和免疫效果。为进一步掌握猪瘟灭活疫苗的免疫效力及免疫期、为该病的防治制定合理的免疫程序及为猪瘟的扑灭和净化提供科学的依据。 相似文献
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目的:为了进一步确定不同生长阶段生猪猪瘟抗体水平,对某规模化猪场不同阶段生猪进行了猪瘟抗体检测分析。方法:在一年之内分季度检测了首免前的4周龄仔猪的猪瘟母源抗体,及经产母猪、首免后及二免后生猪的猪瘟病毒抗体水平。结果:结果显示,4周龄(首免前)仔猪猪瘟(母源)抗体水平偏低,平均为36.65%;其一免和二免的生猪猪瘟抗体水平有明显的提高,平均值分别为56.67.%和93.34%。结论:通过该实验数据分析,及时对规模化猪场进行免疫程序的完善,对提高猪瘟的防控水平具有一定的意义。 相似文献
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山鸡是一种具有较强抗病能力的珍禽,但近年来随着人工养殖及其规模的不断扩大,新城疫(ND)、传染性支气管炎(IB)等禽类传染病的发生日渐频繁,而目前国内对山鸡ND、IB等常见疫病的免疫一直引用家禽的免疫程序,也未能开展系统的免疫抗体消长规律的研究,免疫失败现象时有发生,给山鸡规模化养殖带来了较大的隐患。为此,组织开展了一次针对种山鸡全周期(1个世代、56周)ND和IB的免疫及抗体跟踪检测和免疫效价评估试验。试验结果证明:ND和IB的母源抗体差异较大;早期采用喷雾、滴鼻等方式免疫ND和IB联苗的效果较差,而采用注射免疫的效果明显,并分析提出了山鸡专用的ND和IB推荐免疫程序。 相似文献
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动物免疫失败的因素及应对措施 总被引：2，自引：1，他引：1
根据疫苗免疫的基本原理和抗体形成的一般规律,分析母源抗体、疫苗质量、免疫程序、免疫操作、病原微生物、饲养管理、药物等因素对机体免疫系统或抗体形成的影响,提出疫苗选择、科学制定免疫程序、规范免疫操作、加强饲养管理、合理用药五项提高免疫效果的措施。 相似文献
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脂肪酸对鱼类免疫系统的影响及调控机制研究进展 总被引：5，自引：3，他引：2
替代脂肪源的开发和利用是解决鱼油短缺问题的必然选择。然而,随着替代水平的提高,鱼体常常表现免疫水平和抗病能力降低。鱼油替代的本质为脂肪酸替代,深入研究脂肪酸与鱼类免疫的关系显得尤为重要。本实验综述了脂肪酸对鱼类免疫性能的影响及调控机制。饱和脂肪酸会降低鱼类免疫力,而适量添加n-3长链多不饱和脂肪酸(LC-PUFA)、共轭亚油酸(CLA)或提高n-3/n-6多不饱和脂肪酸(PUFA)的比例有利于鱼体免疫力发挥;饲料中脂肪酸主要通过细胞膜结构、信号传导、类花生四烯酸、细胞因子和类固醇激素等途径对鱼类免疫进行调控。脂肪酸与鱼类的免疫性能具有高度相关性,而调控机制的研究尚有较大空间。未来研究应该侧重于以下几个方面:脂肪酸对免疫相关转录因子的调控机制;鱼类肠道脂肪酸组成改变与菌群结构和免疫性能之间的相关性;环境因子对鱼体脂肪代谢和免疫力的影响;非脂肪酸成分(矿物质、维生素)对鱼类脂肪酸代谢和免疫过程的调控机制。 相似文献
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鱼类免疫应答机制研究进展 总被引：1，自引：0，他引：1
鱼类免疫应答可以分为固有免疫和适应性免疫,但固有免疫发挥主要作用。固有免疫对病原体的识别是通过模式识别受体PRR与病原相关分子模式PAMP的相互结合实现,这与哺乳类相似。但为适应水生生活,鱼类固有免疫对PAMP的识别范围更广,免疫应答的启动条件更低。固有免疫的效应细胞主要是单核/巨噬细胞、嗜中性粒细胞、自然杀伤细胞等,具有吞噬和杀伤功能,还可分泌多种免疫相关的细胞因子,介导发生炎症反应。适应性免疫中,T淋巴细胞通过抗原提呈细胞分解吸收抗原,由主要组织相容性复合物(MHC)类分子递送到细胞表面才能识别。B淋巴细胞分泌产生以免疫球蛋白Ig M为主的抗体分子,而发挥抗体中和作用及免疫调理作用的Ig G在鱼类中比较少见,说明鱼类抗体的免疫功能还处于较低水平。本文综述了近二十年内鱼类免疫应答机制的相关研究进展,为进一步了解鱼类免疫应答机制提供参考。 相似文献
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鱼类粘膜免疫研究进展 总被引：7，自引：1，他引：7
Fish immunology has achieved great progress in recent years. While before 1990s, most researches focused on the fish systematic immunity, and the mucosal immunity of fish had not been given enough attention. Indeed, it has been shown that fish mucosal immunity plays an important role in disease defense. Fish mucosal immunity research has made some exciting progress in this decade. This review will focus on such progress: Constitution of mucosal-associated tissues and distribution of different immune cells, including T/B lymphocytes, granules, monocytes, macrophages, goblet cells, etc, in these sites have been well described with the development of some monoclonal antibody to these cells and associated techniques. Non-specific immune response mechanism of mucosal tissues reported these years, such as secretion of non-specific anti-bacteria and anti-fungi substances in mucus, the respiratory burst, enzyme activity of immune cells and so on, is believed important for fish disease defense. The specific immunity of mucosal tissues also attracts much interest and makes great achievement in antigen presenting, MHC genes, antibody producing and antibody secreting cells, comparison of serum and mucus immunoglobulin, relationships of immune response between different mucosal immune tissues. Whether mucosal immune system is independent of systematic immune system is another interesting question and causes great concern. In recent years, some evidences from phyletic evolution and ontogenesis show that mucosal immunity is prior to systematic immunity in evolution. Dynamics of antibody producing of mucosal tissues and serum in immersion or oral vaccines immunized fish also shows immune response can be elicited in mucosal tissues independent of systematic immune system. Some researchers also begin to pay attention to factors involved in mucosal immune regulations, for instance, neuromodulators and cytokines. The level of these factors changes in fish immune response process but the mechanisms of regulation still remain unknown. Prospect of the promising future of fish mucosal immunity has also been discussed in this review. 相似文献
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维生素C对鱼类营养生理和免疫作用的研究进展 总被引：11，自引：0，他引：11
维生素C在机体内具有非常重要的生理功能。它不仅和鱼类的生长密切相关，而且对鱼类的免疫力、抗病力以及抗应激反应都具有非常重要的影响。然而，由于大多数鱼缺乏合成维生素C所需的L广古洛糖酸内酯氧化酶（L-gulonolactone oxidase，GLO），因此，它们必须通过食物获取维生素C。本文就鱼类对维生素C的需求量及其免疫力和抗应激性反应的影响作一综述。 相似文献
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在人工繁殖鱼类幼苗时，常出现大量骨骼畸形的个体。这些鱼不仅生长速度慢，而且免疫力低，死亡率高，严重影响了水产养殖业的经济效益。综述了饲料维生素营养（A、D、E、K和C）对鱼类骨骼发育和病理学影响的研究进展，从而为幼鱼配合饲料生产性开发和水产养殖业的健康发展提供参考。 相似文献
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Craig A. Shoemaker Phillip H. Klesius Joyce J. Evans Covadonga R. Arias 《Journal of the World Aquaculture Society》2009,40(5):573-585
Vaccination is an important disease management strategy used to maintain human and animal health worldwide. Vaccines developed for aquaculture have reduced antibiotic use in fish production. Original fish vaccines were bacterins (formalin‐killed bacteria) delivered through immersion or injection that induced humoral (antibody) immunity. Next generation vaccines relied on multiple killed antigens delivered with an adjuvant to enhance vaccine effectiveness. Work in the 1990s showed the use of various strategies to develop modified live vaccines for use in fish. A modified live vaccine is a live pathogen that has been rendered non‐pathogenic or avirulent by physical, chemical, or genetic engineering methods. The modified live vaccine typically retains its ability to infect the host which allows for effective presentation of protective antigens to generate cellular immunity (CD4 or CD8 T‐cell responses). Modified live vaccines are advantageous in that they can be easily delivered (i.e., by immersion to young fish) and stimulate both humoral and cellular immunity of long duration. Disadvantages include issues with modified live vaccine safety to the host and environment. A successful modified live vaccine for use in warm water aquaculture is used to highlight the live vaccine strategy. 相似文献
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Duration of immunity in salmonids vaccinated by direct immersion with Yersinia ruckeri and Vibrio anguillarum bacterins 总被引：1，自引：0，他引：1
Abstract. The level of protective immunity was determined for several salmonid species following vaccination by the direct immersion method with commercial Vibrio anguillarum (two serotypes) and Yersinia ruckeri (Hagerman strain) bacterins. The duration of protective immunity varied with the bacterin concentration, size and species of fish, but the duration between the two bacterins was comparable. In fish under 1 g duration of protective immunity was longest when the most concentrated bacterin was used. Generally, immunity lasted in 1-g fish for about 120 days, in 2-g fish for about 180 days, but in 4-g fish and larger immunity lasted for a year or longer. Coho salmon ( Oncorhynchus kisutch ) and sockeye salmon ( O. nerka ) retained immunity for a longer time and pink salmon ( O. gorbuscha ) the shortest time. Chinook salmon ( O. tshawytscha ) and rainbow trout ( Salmo gairdneri ) were intermediate. Field data generally followed the laboratory tests, but the duration appeared somewhat shortened. In one test 20-g rainbow trout were vaccinated by the shower method and no loss of immunity occurred after 311 days. 相似文献
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Abstract. The level of protective immunity in rainbow trout, Salmo gairdneri Richardson, following vaccination by intraperitoneal (i.p.) injection or by direct immersion with Vibrio anguillarum was studied over a period of 46 weeks. Antibody titres to V. anguillarum O-antigen were determined with ELISA at the time of each experimental infection to study the relation between specific antibody production and protective immunity. Both vaccination by i.p. injection and vaccination by direct immersion induced a high degree of protective immunity against vibriosis which lasted for at least 46 weeks. At each experimental infection, the proportions of seropositive fish were lower than the proportions of fish with protective immunity. However, seropositive individuals were found in both experimental groups throughout the study. 相似文献
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Turmeric Powder,Curcuma longa L., in Common Carp,Cyprinus carpio L., Diets: Growth Performance,Innate Immunity,and Challenge against Pathogenic Aeromonas hydrophila Infection 
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下载免费PDF全文 Microbial diseases cause economic loss in aquaculture on a global scale, and the use of commercial antibiotics for disease treatment produces undesirable side effects. As many medicinal herbs have evolved a potent defense against pathogenic bacteria, there is a growing interest in these herbs as sources for natural antibacterial agents. In this context, this study was undertaken to evaluate the effect of turmeric powder (TP), Curcuma longa, on the performance and innate immunity of common carp, Cyprinus carpio L., and its challenge against Aeromonas hydrophila infection. Fish (1.4 ± 0.06 g) were fed 0.0 (control), 1.0, 2.0, or 5.0 g TP/kg diet up to satiation twice daily for 10 wk. After the feeding trial, fish of each treatment were intraperitoneally injected by pathogenic A. hydrophila, and they were kept under observation for 10 d during which the daily mortality was recorded. The growth‐promoting effect of TP was monitored and observed where fish growth and innate immunity increased significantly as dietary TP levels increased. According to the regression curve, the most suitable TP level for optimal fish growth and health was found to be 2.0 g/kg. On the other hand, TP inclusion in the fish diet did not significantly affect fish body contents. The obtained results indicate that TP supplementation is a promising immunostimulant, which could improve fish performance and innate immunity and prevent common carp aermoniosis at a level of 2.0 g/kg diet. 相似文献
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Onset of immunity in salmonid fry vaccinated by direct immersion in Vibrio anguillarum and Yersinia ruckeri bacterins 总被引：3，自引：0，他引：3
Abstract. The fry of several salmonid species were vaccinated by direct immersion in either Yersinia ruckeri or Vibrio anguillarum bacterin and the level of protective immunity was determined by the survival of fish after bath challenge with virulent organisms. The immersion time for effective vaccination was obtained within 5 s and protective immunity was demonstrated within 5 days at 18°C and within 10 days at 10°C. The minimum size at which maximum protective immunity occurred was between 1.0 and 2.5 g. Immunity appeared to be a function of size and not age, but differences in response among several species were indicated. In fish under 1.0 g, the level of protective immunity could be increased using a more concentrated bacterin. The results were similar with both bacterins. 相似文献