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我国鸡传染性支气管炎流行现状及原因分析 总被引：5，自引：1，他引：4
禽的传染性支气管炎是严重危害世界养禽业的重要病毒性传染病。本文从鸡传染性支气管炎病毒、禽冠状病毒宿主范围以及我国鸡传染性支气管炎疫苗的使用和病毒分型等几个方面介绍并分析了该病在我国的流行现状。 相似文献
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《中国预防兽医学报》2022,(1)
禽传染性支气管炎(Avian infectious bronchitis,IB)是由传染性支气管炎病毒(IBV)引起的一种急性、高度传染性的上呼吸道传染性疾病之一,严重危害世界养禽业的健康发展.IBVRNA聚合酶缺乏完整的校正功能,病毒在复制过程中容易出现基因突变及RNA-RNA重组,导致出现新的血清型、基因型和变异毒... 相似文献
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近年来 ,随着养禽业的不断发展 ,家禽疾病的发生更频繁、更复杂 ,给养禽业带来了巨大的损失 ,严重制约了养禽业的快速发展。究其原因 ,主要是免疫失败造成 ,现从几方面分析免疫失败的原因。1 疫苗的质量问题1 1 灭活疫苗中的抗原浓度不足 当灭活疫苗中的抗原浓度不足时 ,不能产生坚强的免疫力 ,达不到免疫的目的 ,可造成免疫失败。1 2 弱毒疫苗受污染 弱毒疫苗中污染网状内皮组织增殖病毒和淋巴细胞白血病病毒时 ,这两种病毒能降低Ｔ淋巴和Ｂ淋巴细胞的活性 ,引起对各种疫苗的免疫应答降低 ,感染传染性贫血因子时也可导致免疫抑制 ,… 相似文献
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鸡传染性支气管炎弱毒苗Ｍａ５株对肉仔鸡免疫效果观察王永玲吴延功蒋贻海张子春王玉东（农业部动物检疫所２６６０３２）俞志涛陈捍卫（山东农业大学）目前，用于我国鸡传染性支气管炎（ＩＢ）免疫预防的疫苗主要是弱毒疫苗，市场上较多见的为Ｈ１２０和Ｈ５２弱毒苗，但... 相似文献
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YAN Yi-ting GOU Xiao-jing LIU Jing HUANG Ya-ming YANG Ji-hui LIU Xing-you 《中国畜牧兽医》2015,42(6):1587-1591
Infectious bronchitis (IB) is an acute and susceptible infectious disease,which has been classified as B loemia and causes a grave threat to the poultry industry.Now,the primary prevention measures of IB are vaccine inoculation.With the diversity of infectious bronchitis virus (IBV) serotype and easy variation,and the weakness of cross protection,the prevention and control of IB were a major problem in poultry industry.In this ariticle,it summarized the molecular biological characteristics, and the development and immunization strategy of the attenuated vaccine of IB to provide scientific references for the research and application of IB attenuated vaccine. 相似文献
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鸡传染性支气管炎病毒免疫机制和免疫预防研究进展 总被引：1，自引：0，他引：1
由鸡传染性支气管炎病毒（Infectious bronchitis virus,IBV）引起的鸡传染性支气管炎（Infectious bronchitis,IB）是高度传染的全球性鸡病之一,严重危害养鸡业。IBV众多的血清型及其基因组的不断变异,给IB的免疫防控带来很大的困难。IBV主要侵害鸡的呼吸系统、泌尿生殖系统和消化系统,病鸡出现呼吸困难、产蛋下降、肾炎和腺胃炎等症状和病变。IBV的特点是变异频繁,血清型复杂,所致疾病的临床表现差异很大。因此,IB已成为养禽业最难控制的疫病之一。鸡对IBV的免疫机制是国内外研究的热点之一。传统疫苗已不能完全保护免疫鸡群,开发IBV基因工程疫苗,从主要免疫原性蛋白的良好表达到免疫策略的不断完善,已成为未来预防IB的趋势。 相似文献
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Infectious bronchitis (IB) is a highly contagious viral disease and is responsible for considerable economic losses in the poultry industry, worldwide. To mitigate the IB-associated losses, multiple vaccines are being applied in the sector with variable successes and thus necessitating the development of a potent vaccine to protect against the IB in the poultry. In the present study, we investigated a bivalent live attenuated vaccine consisting of IB virus (IBV) strain H120 (GI-1 lineage) and D274 (GI-12 lineage) to evaluate its protection against heterologous variant of IBV (GI-23 lineage) in chicken. Protection efficacy was evaluated based on the serology, clinical signs, survival rates, tracheal and kidney histopathology and the viral shedding. Results demonstrated that administering live H120 and D274 (named here Classivar®) vaccine in one day-old and 14 days-old provided 100 % protection. We observed a significant increase in the mean antibody titers, reduced virus shedding, and ameliorated histopathology lesions compared to routinely used vaccination regimes. These results revealed that usage of different IBV vaccines combination can successfully ameliorate the clinical outcome and pathology in vaccinated chicks especially after booster vaccination regime using Classivar®. In conclusions, our data indicate that Classivar® vaccine is safe in chicks and may serve as an effective vaccine against the threat posed by commonly circulating IBV strains in the poultry industry. 相似文献
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Helena Grgi? D. Bruce Hunter Peter Hunton éva Nagy 《Canadian journal of veterinary research》2009,73(3):212-216
Infectious bronchitis (IB) is an economically important viral disease with worldwide distribution. Every country with an intensive poultry industry has infectious bronchitis virus (IBV). The virus rapidly spreads from bird to bird through horizontal transmission by aerosol or ingestion. Sentinel bird studies were carried out in southern Ontario and IBV has been isolated from layer flocks. Genetic analysis of the S1 region of the strains showed that they were not vaccine related. The pathogenicity of selected Ontario variants of IBV isolates was studied and the subsequent work was to determine the degree of protection against field isolates provided by a commonly used vaccine MILDVAC-Ma5 in Ontario. The protection was evaluated by challenging immunized chickens with the respiratory (IBV-ON1) and nephropathogenic (IBV-ON4) viruses. The mean vaccine efficacy for IBV-ON1 was 66.7% indicating that a Massachusetts serotype vaccine would provide some protection against IBV field isolates. 相似文献
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J.R.H. Andrews M.SC. PH.D. 《New Zealand veterinary journal》2013,61(10):194-195
Extract Sir, — In the course of research on infectious bronchitis (IB) in chickens in New Zealand, one strain of IB virus was seleted and attenuated as a local vaccine virus and produced in limited quantities at Massey University for trial purposes. 相似文献
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Liu S Zhang X Wang Y Li C Liu Q Han Z Zhang Q Kong X Tong G 《Veterinary journal (London, England : 1997)》2009,179(1):130-136
Avian infectious bronchitis virus (IBV) causes tremendous economic losses to the poultry industry worldwide. Different serotypes of this virus show little cross-protection. The present study investigated the genotypic relationship between CK/CH/LDL/97I-type strains and reference IBVs based on S1 gene comparisons and the protection provided by vaccination with commercial vaccines and attenuated homologous and heterologous strains. Phylogenetic analysis and the comparison of S1 showed that CK/CH/LDL/97I-type virus might be a new serotype compared to vaccine strains and other types of IBV isolates in China. Protection efficacy was evaluated by morbidity, mortality, and virus re-isolation from the challenged chicks. Complete protection by IBV vaccination was provided by the homologous strain but sufficient respiratory protection was not provided by the commercial vaccines. Heterologous strains against CK/CH/LDL/97I challenge and the development of a vaccine against CK/CH/LDL/97I-type IBV will be necessary to control infectious bronchitis disease in poultry. Further development of the attenuated CK/CH/LDL/97I strain may provide a valuable contribution towards this goal. 相似文献
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The infectious bronchitis virus (IBV) is the cause of avian infectious bronchitis (IB). IB is one of the most highly contagious diseases, which results in many economic losses in the poultry industry worldwide. The nature of this virus is such that it generates new genotypes continuously. Proper vaccination is the most suitable way of combatting IB. One of the novel genotypes of IBV, which has been circulating in the Middle Eastern countries, is the variant 2 (IS-1494/GI-23) genotype. This study aims to design and produce an autogenous variant 2 vaccines. After isolation and characterization of the Iranian variant 2, the inactivated vaccine was formulated according to the OIE guidelines, and its different aspects (Purity, titration, inactivation, immunization) were evaluated. The designed vaccine passed all of OIE quality control standards. In the assessment process, the protection rate in the groups receiving the variant 2 and commercial vaccines was 67 % and 60 %, respectively. Although the differences were not significant, they indicated better protection, and the viral load in the feces and the kidney of the group receiving the variant 2 vaccine was lower than that in the commercial vaccine. It is suggested that the variant2 strain should be added as one of the local strains to the commercial inactivated vaccines in areas affected by this genotype. The use of this vaccine in layer and breeder flocks can help to protect them against variant 2 during the production phase. Also, the transfer of maternal antibodies to offspring can provide strain-specific immunity for one-day-old chickens. 相似文献