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1.
O. O. Odedara J. d’A. Hughes A. C. Odebode B. O. Odu 《Journal of General Plant Pathology》2008,74(4):322-325
Leaf samples of Lablab purpureus collected from two agroecological zones of Nigeria—the northern guinea savanna zone (NGSZ) and the derived savanna zone (DSZ)—were
infected with viruses when serologically indexed against available antisera. Approximately 31.1 and 81.1% of the leaf samples
collected from the NGSZ and DSZ, respectively, were infected. Seven viruses were found: Bean common mosaic virus (BCMV), Cowpea aphid-borne mosaic virus (CABMV), Cucumber mosaic virus (CMV), Cowpea mottle virus (CPMoV), Cowpea severe mosaic virus (CPSMV), Southern bean mosaic virus (SBMV) and Tobacco mosaic virus (TMV) were detected from samples collected from NGSZ, while CMV, CPMoV, Cowpea mosaic virus (CPMV) and CPSMV were detected from samples from DSZ. 相似文献
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网状内皮组织增殖病病毒感染SPF雏鸡外周血液T,B淋巴细胞数量变化 总被引:3,自引:1,他引:3
应用SPA菌体花环法检测网状内皮组织增殖病病毒(REV)感染SPF雏鸡外周血液T、B淋巴细胞数量动态变化。结果发现,1日龄SPF雏鸡感染REV后7~49d外周血液T淋巴细胞数量,14~49dB淋巴细胞数量均明显低于对照组。表明感染REV的SPF雏鸡外周血液的细胞免疫和体液免疫水平均下降。 相似文献
4.
同胚增殖鸡新城疫病毒和传染性支气管炎病毒的效果观察及免疫应答反应 总被引:6,自引:0,他引:6
鸡新城疫病毒(NDV)和鸡传染性支气管炎病毒(IBV)混合在同一鸡胚中增殖,当NDV和IBV接种浓度控制在一定范围时,最佳收毒时间选择使NDV有足够时间增殖到最佳滴度,且在这一时间内不至于因孵育时间过长而致IBV毒力减弱。结果表明NDVLasota株经10倍稀释分别与4株IBV1000倍稀释液等体积混合后接种,能在同一鸡胚中正常增殖,即96h收毒,血凝(HA)方法测定两种病毒的血凝价均能达到最佳滴度,其血凝价不低于各自单独增殖的滴度。4种IBV株与NDV同胚增殖的HA滴度进一步证实,在合适的条件下,IBV均不对NDV的复制产生干扰作用,4种IBV的血凝价无明显差异。免疫试验中用同胚增殖两种病毒二联苗接种,鸡体血清中可产生抗两种病毒的HI抗体,与各自单独接种时的HI抗体水平几乎一致。本试验中制备的IB血凝抗原在4℃保存一个月,其血凝活性保持不变。IBV微量血凝抑制(HI)试验特异性测定结果证实,用自制IBV血凝抗原进行HI试验检测鸡IB阳性血清均能产生稳定的特异性反应,并且无交叉反应。说明HI试验是检测IBV抗体水平的有效可行的方法。 相似文献
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某鸡场暴发主要以侵害鸡肾脏的疾病,引起肾脏肿大、苍白,肾小管和输尿管有白色尿酸盐沉积,伴有下痢。产蛋鸡产蛋下降,雏鸡的死亡率达25%~90%。从感染鸡分离到1株疑为鸡肾型传染性支气管炎病毒,接种鸡胚,鸡胚出现侏儒化、卷曲等特征性病变。 相似文献
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猪瘟病毒E2蛋白研究进展 总被引:1,自引:0,他引:1
猪瘟(Classical Swine Fever,CSF)是由猪瘟病毒(Classical Swine Fever Virus,CSFV)引起的一种急性、接触性传染病。目前该病流行于除北美洲和大洋洲以外的其他大洲和地区,呈世界性分布,在一些原已宣布消灭猪瘟的欧洲国家(荷兰、比利时、英国、德国、意大利、西班牙等)又相继复发。虽然我国长期坚持全面接种猪瘟兔化弱毒疫苗,但目前猪瘟在我国依然存在,流行特点从以往的频发大面积流行转变为无规律区域性的散发,隐性持续性感染病例增多,因此应明确猪瘟病毒的基因组结构和最具免疫防制研究价值的抗原蛋白结构,为研制新型有效的疫苗和诊断试剂提供理论依据。本文就猪瘟病毒的基因组结构、猪瘟病毒E2蛋白的结构、功能、所包含的抗原表位以及E2蛋白的表达应用等方面的研究进展作以综述。 相似文献
8.
Characterisation of three novel canine osteosarcoma cell lines producing high levels of matrix metalloproteinases 总被引:1,自引:0,他引:1
Loukopoulos P O'Brien T Ghoddusi M Mungall BA Robinson WF 《Research in veterinary science》2004,77(2):131-141
Three canine osteosarcoma cell lines were established from spontaneous pelvic and radial osteosarcomas. The cell populations cultured exhibited characteristics of malignancy and consisted of adherent, pleomorphic, mostly large spindle-shaped or polyhedral cells, characterised by the presence of numerous cytoplasmic granules and vacuoles. The main ultrastructural features included the presence of abundant rough endoplasmic reticulum and numerous cytoplasmic vesicles, deposit vacuoles and small cytoplasmic protrusions. Zymography showed that the cell lines produce high levels of MMP-2 and MMP-9, enzymes directly involved in crucial aspects of the metastatic process. Consistent with their osteoblastic lineage and malignant phenotype, all cell lines were immunoreactive to vimentin, osteopontin, PCNA, p53, MMP-2 and MMP-9, while they were negative for cytokeratin, desmin, SMA, Factor VIII, NSE, GFAP, Rb and p21 protein. No retroviral particles or RNA were detected ultrastructurally or with RT-PCR, although the possibility of viral involvement in osteosarcoma cannot be excluded. The new cell lines provide excellent in vitro models that may allow further studies on the pathobiology of canine osteosarcoma to be undertaken. 相似文献
9.
牛病毒性腹泻-粘膜病病毒TaqMan荧光定量RT-PCR检测方法的建立及初步应用 总被引:1,自引:0,他引:1
为建立-种牛病毒性腹泻-粘膜病病毒(BVDV)的快速检测方法,根据GenBank中登录的BVDV基因序列,针对5’UTR的保守序列,设计合成了一对特异性引物和一条TaqMan荧光探针。通过对反应条件和反应体系进行优化,建立了一种能快速定量检测BVDV的荧光定量RT—PCR检测方法。通过对20份胎牛血清样品和猪瘟细胞苗半成品进行检测,对该方法的特异性、敏感性和重复性进行试验。结果显示,建立的方法能检测到BVDV,而对CSFV、PRRSV和MDBK细胞的扩增结果均为阴性,具有高度的特异性。在所检测的20份样品中,BVDV阳性6份(30%)。对所构建的标准品进行检测,在10^2-10^8拷贝/μL的范围内可以得到良好的动力学曲线,能检测低至10^3-10^4拷贝/mL的病毒量。表明所建立的检测方法具有快速、特异、灵敏、重复性好等特点,可用于临床及科研中对BVDV的快速定量检测和对牛血清及猪瘟兔化弱毒疫苗等生物制品中是否污染BVDV进行监测。 相似文献
10.
To control the spread of bovine viral-diarrhoea virus (BVDV), test-and-cull schemes have been used in Scandinavian countries, with success, when combined with strict control of new animal introductions into herds. In situations where BVDV reintroduction is likely to occur, it is necessary to assess precisely the expected efficiency of test-and-cull schemes. The objective of this study was to compare, by simulation, the persistence and consequences of BVDV infection in a fully susceptible dairy herd with either a test-and-cull scheme or no control action. We used a stochastic individual-based model representing the herd structure as groups of animals, herd dynamics, the contact structure within the herd and virus transmission. After an initial introduction of the virus into a fully susceptible herd, the frequency of purchases of animals that introduced the virus was simulated as high, intermediate or null. Virus persistence and epidemic size (total number of animals infected) were simulated over 10 years. The test-and-cull reduced the epidemic size and the number of days the virus was present except in herds with complete prevention of contact between groups of animals. Where no virus was reintroduced, virus persistence did not exceed 6 years with a test-and-cull scheme, whereas the virus was still present 10 years after the virus introduction in some replications with no control action (<2%). Where frequent purchases were made that led to virus introduction (6 within 10 years), with an intermediate virus transmission between groups, the probability of virus persistence 10 years after the first virus introduction fell from 31% to 8% with the test-and-cull scheme (compared to the do-nothing strategy). Within the newly infected herd, the test-and-cull scheme had no effect, on inspection, on the number of PI births, embryonic deaths or abortions over 10 years. Given this, the economic efficiency of the test-and-cull scheme should be further investigated. 相似文献