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1.
疫苗免疫在禽病控制上的进展   总被引:2,自引:0,他引:2  
疫苗免疫已有1000多年的历史,但只有进入二十世纪以后,疫苗科学才得到了迅速的发展。目前商品性疫苗主要是弱毒活疫苗,灭活疫苗和亚单位疫苗三大类,它们有各自的优点和不足。新一代的疫苗,如基因缺失疫苗,载体疫苗,核酸疫苗和病毒-抗体复合物疫苗等,将从质和量两方面改善其免疫应答和免疫保护,并导致新的疾病控制策略的出现。  相似文献   

2.
Conventional vaccines have been used for some 200 years, primarily to control infectious diseases. It is envisaged that such vaccines will continue to be used and new ones developed using conventional technology. However, in addition to conventional vaccines, novel approaches using biotechnology are already in use and many more are in various stages of development. These novel vaccines are not only being used to control infectious diseases, but also to improve productivity of livestock by modulating hormones, for gender selection, as well as in controlling ectoparasites. The recent developments in vaccination technology in all of these areas are described.  相似文献   

3.
Parasite vaccines--a reality?   总被引:40,自引:0,他引:40  
Over the last decade, the anti-parasitics market has been the fastest growing sector of the overall $18 billion animal health market. While drugs for the treatment of parasites of livestock still dominate this sector and will continue to be developed or re-formulated, because of consumer demands for chemical-free food and of concerns regarding the environment and animal welfare there is a growing interest in the development of safe and effective vaccines. There is also a call for vaccines in the lucrative $3 billion-plus companion animal market. These demands for vaccines will add a greater impetus to an area that has seen tremendous success in the last 15 years. A number of anti-parasite vaccines have been developed, e.g. the recombinant 45w and EG95 oncosphere proteins against Taenia ovis and Echinococcus granulosis, respectively, and the Bm86 vaccine against Boophilus microplus. In addition, the cathepsin L vaccines against the liver fluke, Fasciola hepatica, and the H11 vaccine against Haemonchus contortus are progressing well. There are also many additional vaccine candidates for H. contortus and for other nematodes such as Ostertagia and Trichostrongylus spp. that may ultimately lead to broad-spectrum gastrointestinal worm vaccines. Live or attenuated-live vaccines are available for the control of avian coccidiosis, toxplasmosis in sheep and anaplasmosis in cattle, although molecular vaccines against protozoans are still proving elusive. The wealth of information in genomics, proteomics and immunology that has been forthcoming together will new methods of vaccine production and delivery should see many new vaccines reach the marketplace in the near future.  相似文献   

4.
Molecular technology has given us a greater insight into the aetiology of disease, the functioning of the immune system and the mode of action of veterinary pathogens. The knowledge gained has been used to develop new vaccines with specific, reactive antigens which elicit protective immune mediated responses (humoral and/or cell mediated) in the host. These vaccines should not burden the immune system by initiating responses against non-essential antigens. However, the efficacy of these vaccines is only as good as the delivery technology or route used to present them to the immune system. Some vaccines, traditionally given by the parenteral route, are now given by the natural route; either orally or intranasally. Two major advantages, often interrelated, are the rapid onset of immunity and stimulation of the local, mucosal immunity. These new technologies are now making an impact on current vaccine development. The balance has to be found between what is technologically feasible and what will provide at least as good a protective immunity as current, conventional vaccines. As new and emerging diseases appear globally, new opportunities arise for molecular and conventional technologies to be applied to both the development and delivery of novel vaccines, as well as the improvement of vaccines in current use.  相似文献   

5.
Each year, millions of cats and dogs are euthanized worldwide. There are insufficient resources to control shelter animals in developed countries, as well as feral cat and wild dog population levels, with current surgical sterilization techniques. Thus, population control of these animals will likely depend on the development of new non-surgical methods for cat and dog sterilization. One promising area of research is the development of contraceptive vaccines, or immunocontraceptives. In this article, previous approaches aimed at developing contraceptive vaccines will be reviewed, with a focus on those most related to sterilization of cats and dogs. There are a number of steps in reproduction that have been, or could be, targeted by the immune system, and the advantages and obstacles for inducing immunity to each of these will be discussed. Our current understanding of how these vaccines cause sterility, and our current ability to dissect these mechanisms in cats and dogs, also will be discussed.  相似文献   

6.
脑心肌炎主要是由脑心肌炎病毒引起的一种急性传染病,危及多种动物和人,对人类生命健康和经济发展造成了较大的危害。国外对于该病已经有了有效的疫苗,对于该病毒的研究也主要集中在病毒的致病机制方面。国内还没有研制出安全有效的疫苗,而须采用进口疫苗,致使免疫猪的代价太大,因而难以推广。随着以疫苗免疫为主的防控措施逐渐受到关注,基因工程疫苗成为脑心肌炎疫苗研究的热点。论文就脑心肌炎疫苗的应用现状和新型疫苗的研发情况进行综述。  相似文献   

7.
Rotaviruses (RVs) are the main aetiologic agent of severe acute diarrhoea in children under the age of 5, worldwide. Given that the currently available preventive measures to fight against the transmission of RV disease are not sufficiently effective, vaccination likely represents the only efficacious adapted response to the massive impact of this infection. Although the two current RV vaccines have shown good tolerance and significant efficacy to protect infant against severe RV disease, their development have raised key questions that are still unanswered regarding their cost, efficacy and safety. These two vaccines have in common the disadvantages related to the use of oral attenuated live viruses which limit their implementation in both developed and developing countries. In order to overcome these hurdles, it is important to support the development of new, non-replicating vaccines which will not suffer the potential disadvantages of the present vaccines. New approaches and other routes of administration are being tested in animal models and soon will be evaluated in humans. Among those are viral-like particle-based vaccines which have provided the most promising results. Finally, the epidemiology of the disease which differs in developed and developing countries can affect decisions about vaccine composition and delivery. The answer brought by the development of new RV vaccines could reside in developing several types of RV vaccines specifically designed to be used in different settings.  相似文献   

8.
During the past century, research on animal diseases has focused on the characterization of specific etiologies and disease control strategies. Many diseases affecting domestic animals have been successfully controlled using various methods, including vaccination, management, vector control, or antimicrobial agents. A number of microorganisms have proven resistant to these efforts. Control of these organisms requires the development of new strategies. As practitioners and researchers, we need to consider approaches that encompass the entire realm of disease expression from molecular to immune responses and interactions with other functional systems (e.g., endocrine, neurologic, and vascular systems). We need a basic understanding of effective immune responses enabling the tailoring of vaccines to produce the desired response. This tailoring of host responses is augmented by the use of vaccines that use host growth factors, cytokines, or costimulatory molecules to bias the ensuing response. Intestinal microbial flora of food-producing animals can be managed to optimize health and minimize colonization by pathogenic organisms, especially zoonotic agents. New systems for the delivery of cytokines and other factors that favor optimal intestinal health and homeostasis need to be researched and evaluated. With time, it is likely that our clients and the consumers will be less tolerant of antibiotic usage. They will be more aware of the zoonotic potential of many microbes that colonize food animals. Food safety issues will be a continuing concern, as will the protection of our water supply from contamination from feedlots and pasture runoff. We are in the dawn of a new century, and, it is hoped, a new era of discovery of enteric disease pathogenesis and control.  相似文献   

9.
Live vaccines have a number of advantages over inactivated ones--above all in respect of the stimulation of cell-mediated immune reactions. Various live vaccines, based on viruses, bacteria, fungi or parasites, have been approved for use in Germany in animals used as a source of food. Safety requirements obviously play a more important role for live vaccines, both in vaccine development and in batch testing, than with inactivated vaccines. Vaccine strains isolated from tissue samples must be clearly distinguishable from field strains. The safety of overdoses and the spread of the vaccine strain in the immunized animals have to be investigated, as well as shedding of the vaccine strain and its safety in non-target species. Any impact of a live vaccine strain on humans and the environment must be assessed. Live vaccines will remain an important research field in the long term, with efforts focused on developing deletion mutants and vector vaccines.  相似文献   

10.
猪圆环病毒2型分子流行病学及疫苗研究进展   总被引:2,自引:0,他引:2  
猪圆环病毒2型(PCV2)在世界范围内广泛分布,主要以PCV2a和PCV2b两种基因型为主,PCV2b亚型为当前流行基因型。现有商品化疫苗主要针对PCV2a型病毒,也可对PCV2b型病毒产生部分交叉保护,但不能显著控制PCV2b型病毒在猪群中的传播。除此之外,由于已有的商品化疫苗以传统疫苗为主,存在种毒增殖难、疫苗生产周期长等缺点。因此,研发PCV2b新型疫苗可能成为未来PCV2疫苗研制的主要方向。对PCV2的分子流行病学及疫苗研究现状进行了综述,以期为PCV2疫苗的研究提供参考。  相似文献   

11.
禽用核酸疫苗的研究进展   总被引:4,自引:0,他引:4  
核酸疫苗是近 2 0年来发展起来的一种新型疫苗 ,它应用现代生物工程技术和分子生物学技术 ,克服了传统疫苗所存在的一些问题 ,具有传统疫苗不可比拟的优点 ,成为国内外学者争相研究的热点之一 ,呈现出良好的发展势头和应用前景。在禽病学领域 ,禽流感、新城疫、传染性支气管炎、传染性法氏囊等疾病的核酸疫苗得到了较为深入的研究 ,为禽用核酸疫苗乃至其他领域的核酸疫苗的进一步研究提供了有益的参考 ,也将会为养禽业带来不可估量的经济效益。通过对禽用核酸疫苗研究概况的综述 ,不仅可以了解国内外研究动态 ,借鉴最新的研究方法和研究思路 ,也可以发现问题和提出问题 ,进而寻求新的研究方向  相似文献   

12.
DNA vaccination represents one of the most recent novel approaches to vaccine development. Experimentally, DNA vaccines induce a broad range of long lasting immune responses including humoral and cell-mediated immunity against infectious diseases in humans and animals. Furthermore, DNA vaccines are potentially useful for the treatment of autoimmune diseases or cancer. However, most information on the efficacy of DNA vaccines has been generated in mice and studies in larger animals are limited. In this review, the potential application of DNA vaccines in livestock and pet animals are discussed. The principle of this new technology, its potency and future perspectives for use in veterinary medicine will be outlined.  相似文献   

13.
疫苗佐剂是使疫苗免疫原性充分发挥的工具,目前动物疫苗佐剂主要以铝盐佐剂和油乳佐剂为主。近年来基因重组疫苗和亚单位疫苗发展迅猛,而这些新型疫苗与传统疫苗相比免疫原性较弱,这就对佐剂提出了更高的要求。当前针对佐剂的研究层出不穷,部分佐剂如MF59、AS01、AS03等已经在人用疫苗中成功应用,但应用于动物疫苗还有技术难题需要攻破。蜂胶佐剂目前在动物疫苗中应用较广,且已经占有了一定的市场份额。为充分比较现有新型疫苗佐剂的优缺点,为后续疫苗佐剂的研究提供参考,就目前广泛研究的新型动物疫苗佐剂进行综述。  相似文献   

14.
Brucella abortus vaccines play a central role in bovine brucellosis control/eradication programs and have been successfully used worldwide for decades. Strain 19 and RB51 are the approved B. abortus vaccines strains most commonly used to protect cattle against infection and abortion. However, due to some drawbacks shown by these vaccines much effort has been undertaken for the development of new vaccines, safer and more effective, that could also be used in other susceptible species of animals. In this paper, we present a review of the main aspects of the vaccines that have been used in the brucellosis control over the years and the current research advances in the development of new B. abortus vaccines.  相似文献   

15.
In 1997, highly pathogenic (HP) H5N1 avian influenza virus (AIV) caused infections in poultry in Hong Kong and crossed into humans, resulting in a limited number of infections including 18 hospitalized cases and six associated deaths. The unique ability of this, AIV to infect both poultry and people raised a concern for the potential of humans to be biological as well as mechanical vectors of this AIV to poultry. The current study was undertaken to determine if existing vaccines and their technologies could be used during an outbreak to protect poultry. Commercial and experimental inactivated whole H5 AIV and baculovirus-expressed AIV H5 hemagglurinin protein vaccines provided protection from clinical signs and death in chickens after lethal challenge by human-origin HP H5N1 Hong Kong strains 156/97 and 483/97. The commercial and experimental inactivated vaccines had mean protective doses ranging from 0.25 to 0.89, which represents the milligrams of viral protein in the vaccines that provided protection from death in half of the birds. Furthermore, the vaccines reduced the ability of the challenge AIV to replicate in chickens and decreased the recovery of challenge AIV from the enteric and respiratory tracts, but the use of a vaccine will nor totally prevent AI virus replication and shedding. Existing vaccines will protect poultry from mortality and reduce virus replication from the new HP AIV strain that can infect both poultry and humans.  相似文献   

16.
猪流行性腹泻(porcine epidemic diarrhea,PED)是危害养猪业健康发展的重要疾病之一,具有急性、高度传染性的特征,给养猪业造成了严重的经济损失。猪流行性腹泻病毒(porcine epidemic diarrhea virus,PEDV)感染会破坏动物机体的消化系统,造成患病猪食欲下降、呕吐以及严重腹泻等,且药物治愈后的仔猪也会因为生长发育不良等因素严重影响生产,给养殖户带来巨大的困扰。2010年PEDV高致病变异毒株在中国暴发流行,导致PED的发病率和死亡率大幅升高,严重影响中国养猪生产。此次PED的暴发流行引起了养猪行业的密切关注,相关研究领域的学者对PEDV致病机制和PED新型疫苗进行了更加深入的研究,亚单位疫苗、病毒活载体疫苗、细菌活载体疫苗、转基因植物疫苗和核酸疫苗5种PED新型疫苗相继被开发,并取得全新的突破和进展。与传统的PED灭活苗和PED弱毒疫苗相比,PED新型基因工程疫苗具有安全性好、制备简单、免疫效果好等优点。文章着重对PEDV发病机理和5种PED新型疫苗的研究进展展开综述,从而加深对PEDV和PED新型疫苗的了解,以期为PEDV感染的预防和控制措施提供参考。  相似文献   

17.
Porcine epidemic diarrhea (PED) is one of the important diseases that endanger the healthy development of the pig industry.It has acute and highly infectious characteristics,causing severe economic losses to the pig industry.Porcine epidemic diarrhea virus (PEDV) infection could destroy the animal's digestive system,cause the appetite of sick pigs to decline,vomit,and severe diarrhea.And the piglets cured by drugs will also have a serious impact on production due to factors such as poor growth and development,which will bring huge problems to the farmers.The outbreak of PEDV highly pathogenic mutant strains in China in 2010 led to a significant increase in the incidence and mortality of PED,which severely affected pig production in China.The outbreak of PED has drawn close attention from the pig industry.Scholars in related research fields have conducted more in-depth research on the pathogenic mechanism of PEDV and the new PED vaccine.Five new types of PED vaccines,including subunit vaccine,virus live vector vaccine,bacterial live vector vaccine,transgenic plant vaccine and nucleic acid vaccine,have been developed successively,and new breakthroughs and progress have been made.Compared with the traditional PED inactivated vaccine and PED attenuated vaccine,the new PED genetically engineered vaccine has the advantages of good safety,simple preparation,and good immune effect.This article focuses on the pathogenesis of PEDV and the research progress of five new PED vaccines,so as to deepen our understanding of new PEDV and PED vaccines,in order to provide references for prevention and control measures of PEDV infection.  相似文献   

18.
牛传染性鼻气管炎(IBR)是由牛传染性鼻气管炎病毒(IBRV)感染家养牛引起的一种热性接触性传染病。由于缺乏有效的治疗性药物,因此疫苗免疫仍然是防控该病的关键措施。针对该病常用的疫苗主要有灭活疫苗和活疫苗,而基因缺失活疫苗由于具有免疫标识,已成为新型疫苗研发的主流方向。一些发达国家已利用基因缺失标记疫苗,如IBRV gE缺失疫苗,进行免疫根除计划并净化了该病。然而,由于现存的疫苗仍存在免疫抑制与潜伏感染等问题,亟需研制更有效的标记疫苗。论文就牛传染性鼻气管炎病毒的病原学特征、免疫抑制及疫苗研发进展进行综述,以期为IBR有效疫苗的研发及其在防控上的应用提供参考。  相似文献   

19.
动物核酸疫苗的研究现状及发展前景   总被引:2,自引:2,他引:0  
王凯 《中国畜牧兽医》2010,37(8):186-188
核酸疫苗是近年来备受人们关注的一种新型疫苗。核酸疫苗以其特有的可诱导机体产生全面的免疫应答,对不同亚型的病原体具有交叉防御作用,以及安全、可靠、生产方便等优点被称之为“疫苗的第三次革命”。核酸疫苗由编码能引起保护性免疫反应的病原体抗原的基因片段和载体构建而成,包括DNA疫苗和RNA疫苗,目前研究较多的是DNA疫苗。DNA疫苗是指含有编码抗原基因的真核表达质粒DNA,经直接接种体内后,可被体细胞摄取,并转录、翻译、表达出相应的抗原,然后通过不同途径刺激机体产生针对此种抗原的应答。作者简单介绍了动物核酸疫苗的特点、免疫机制、免疫影响因素及在畜禽传染病中的应用,此外还分析了核酸疫苗的发展前景等问题,从而为核酸疫苗的发展提供了新思路和新途径。  相似文献   

20.
New approaches to nematode control in sheep are urgently needed as anthelmintic drench resistance becomes ever more widespread among worm populations. Here we briefly describe and assess a number of new technologies which will become increasingly important in anti-nematode control programmes in the future. These include vaccines, immunomodulants, strategic grazing practices, the use of biological agents to destroy nematode larvae, biological anthelmintics and targeted silencing of genes regulating nematode development.  相似文献   

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