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血清10型鸭疫里默氏菌4个亚型的分析 总被引：8，自引：1，他引：8
采用琼脂扩散沉淀试验，对只与血清10型鸭疫里默氏菌参考菌株H2199的抗血清发生凝集反应的58株分离株进行了抗原性分析。根据沉淀反应模式，可将这些分离株分成4类：第1类是以C2为代表的30株；第2类是以C449为代表的3株；第3类是以C459为代表的6株；第4类是以C598为代表的19株。第1类分离株与H2199具有相同的热稳定抗原模式，其他类型的分离株与各类代表菌株的热稳定抗原具有同一性，但彼此之间以及与H2199之间存在明显的抗原差异。用未经吸收和经过吸收的抗血清经玻片凝集试验和试管凝集试验对H2199和4类分离株彼此之间的抗原关系进行了进一步的分析。以C2为代表的分离株属于真正的10型；以C459为代表的分离株与H2199存在显著的抗原差异，它们除了与H2199拥有共同抗原外，还有自己的特异性抗原成分，因此，H2199与C459之间的抗原关系可描述为ab．bc。类似的抗原关系还分别存在于H2199与C598、C598与C449之间。但是，在试管凝集试验中，分别相对于C449、C459和C459而言，菌株H2199、C598和C449缺乏自己的特异性抗原成分，因此，H2199-C449、C449-C459、C598-C459之间的抗原关系可分别描述为b-bc。基于上述结果，可将只与10型抗血清发生凝集反应的分离株分成4个亚型，分别以菌株H2199(或C2)、C449、C459、C598作为亚型1～4的代表菌株。 相似文献
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通过胰蛋白酶裂解坏死梭杆菌FN（A）型毒力菌株菌体,分别以菌体裂解物上清和沉淀作为抗原免疫家兔制备血清。利用SDS-PAGE/Western-blot技术在菌体中筛选出4种具有免疫原性的组分,通过免疫后的攻毒试验,筛选出1种具有免疫保护性的抗原。抗原分离纯化后,进行N端氨基酸序列测定、免疫试验及生物学特性研究,据试验结果可初步判定该抗原为溶血素类似物或一种新发现的抗原物质。该抗原不仅能使机体产生保护性免疫反应,而且不同菌株中此种抗原间可产生明显的交叉免疫。 相似文献
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目的：蜂胶是一种具有多种生物活性的天然产物，本文研究了微囊化的杨树属蜂胶醇提物的体外益生特性。方法：利用微胶囊法制备蜂胶，通过2株双歧杆菌属，2株乳杆菌属，1株片球菌属和1株埃希氏菌属的体外静态发酵评估蜂胶提取物促进益生菌生长及抑制有害菌生长的潜力。结果：蜂胶提取物可不同程度改善乳杆菌、双歧杆菌菌株和片球菌菌株的生长，对大肠杆菌的生长起到抑制作用，并增加短链脂肪酸的生成。结论：蜂胶可促进益生菌的生长，可考虑作为益生元应用于功能食品。 相似文献
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现代畜牧营养科学正向着无毒、无公害、无“三致因子”、无残留、高效完善方面发展,以能生产出高质量的畜产品,并提高经济效益。研究表明:蜂产品——蜂胶、蜂花粉符合这种需求,成为营养学者关注的课题。 国外大量研究表明:蜂胶具有较强的辅佐抗原免疫作用,能增强抗体的产生,使血清总数CP和r-球蛋白含量增加,增强白细胞和巨噬细胞的吞噬能力,从而提高机体的免疫力。可以认为:蜂胶对感染性疾病的疗效一方面是由于其具有抗菌、抗原虫、抗病毒作用,抑制了致病微生物的生长和繁殖;另一方面则由于其增强了机体的特异性和非特异性免疫能力,提高机体的 相似文献
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猪链球菌是猪的重要病原菌之一，可引起猪的多种疾病，侵害各年龄阶段的猪，通常以败血症、脑膜炎、关节炎、淋巴结炎为主要特征，还可引起人类脑膜炎、败血症等，导致严重疾患，甚至死亡。链球菌的抗原构造比较复杂，有核蛋白抗原（P抗原），无群特异性；群特异性抗原（C抗原），具有群特异性；型特异性抗原，又称表面抗原，具有型特异性。根据细菌的荚膜多糖抗原（CPS）可将之分为35个血清型，即1型～34型和1／2型（同时含有1型和2型抗原的菌株）。多数参考株来源于人，17、18、19型和21型来源于健康猪，20型和30型来源于病牛，33型来源于羔羊， 相似文献
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巴氏杆菌病与魏氏梭菌性肠炎是家兔的两种主要细菌性疾病，其发病率和死亡率均较高。蜂胶作为一种良好的免疫增强剂，不仅能够增强机体的免疫功能，而且还具有抗菌消炎的功能。为此，我们利用蜂胶作为佐剂，研制了兔巴氏杆菌魏氏梭菌二联蜂胶灭活疫苗。现将研制情况报告如下：１ 材料与方法１．１ 菌种兔巴氏杆菌系本所分离菌株，经鉴定为１：Ａ型。Ａ型魏氏梭菌菌种由中国兽药监察所提供。巴氏杆菌马丁肉汤培养物皮下或肌肉接种５～１０个活菌，能致死敏感兔。魏氏梭菌１８～２２小时肉肝汤培养物肌肉接种０．５ｍＬ／只，攻毒兔死亡或出… 相似文献
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蜂胶(Propolis)是指蜜蜂从树芽、树皮或其他植物的幼芽上采集的树脂,混入腭腺分泌物和蜂蜡等物质而形成的一种具有芳香气味的胶状固体物质,是蜜蜂用来防护、抵御病虫害和病原微生物入侵巢房的御敌物质,同时也是作为修补巢房和内环境消毒杀菌的一种特殊物质。蜂胶含几十种生物活性物质、多种维生素、氨基酸、脂肪酸、多糖及酶等,具有广谱抗病毒、抗细菌和抗霉菌作用。将其配合抗原注入机体,可激活生物体自身的免疫防卫系统,增强补体功能,增加免疫细胞数量,促进抗体产生,从而增强机体免疫功能。早在20世纪60年代,原苏联喀山兽医学院就对蜂胶影响动物机体免疫活性方面进行了观察。随后,国内外众多学者不断对蜂胶的免疫功能进行研究并取得了满意的效果。 相似文献
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Immunity assays on sheep sera using passive mouse protection tests showed that vaccines containing more than 4 strains of Pasteurella multocida did not give a good immunity. The immune response was not enhanced by the use of an oil adjuvant, and high concentrations of bacteria had only a partial positive effect. Attempts to extract selectively the protection-inducing antigen(s) from P. multocida by veronal, phenol or potassium thiocyanate extraction were unsuccessful. Furthermore, it was found that sheep antisera to the recognized type strains of P. multocida afforded only limited protection against a number of field strains. We concluded from this that successful immunization against ovine pasteurellosis will depend on either the identification of a strain of P. multocida that gives a wide spectrum of immunity or the discovery of a live mutant suitable for vaccine production and the definition of cultural conditions that promote the expression of a common immunizing antigen. 相似文献
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犬瘟热的诊断及其预防免疫的研究进展 总被引：36，自引：7，他引：29
本文对犬瘟热（CD）的诊断、预防免疫和免疫失败的影响因素及犬瘟热病毒（CDV）的宿主范围进行了综述。CDV不仅感染陆生食肉动物，而且也感染水生食肉动物，并且其宿主范围还在不断扩大。CDV感染主要采用病毒分离、特异性病毒抗原或特异性核酸检测等方法确诊。疫苗包括灭活的CDV疫苗、麻疹病毒（MV）异源苗及CDV弱毒活苗。疫苗接种犬的免疫反应主要取决于毒株特性及犬的应答能力，只有弱毒活苗能诱导产生持久而坚强的保护力。尽管多年来CDV弱毒活苗的使用控制了CD的发生，但最近免疫过的犬发生CD的病例并不少见。分析免疫失败的原因，主要是母源抗体干扰、疫苗质量差、其它病毒的免疫抑制以及CDV流行株可能发生了变异等因素的影响。 相似文献
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D.L. Emery 《Veterinary microbiology》1984,9(5):453-466
In order to identify those bacterial antigens which might be involved in immunity against ovine footrot, antisera were raised in sheep to 6 proteins in the outer membrane complex (OMC) of one strain of Bacteroides nodosus. Examination of the specificity of these antisera by Western blotting, crossed immunoelectrophoresis (XIEP) and IEP, revealed that they recognized the homologous OMC protein, but did not precipitate either undenatured pili or OMC, nor could they agglutinate the homologous bacteria. In contrast, anti-OMC and anti-pili sera could precipitate OMC or pili respectively, and agglutinate whole bacteria. Subsequent analysis of these sera against 5 strains of B. nodosus from different serogroups revealed that Proteins 1, 3 and 4 had a similar antigenic structure in all strains examined. The reactivity of anti-pili sera was restricted to homologous bacteria whereas anti-pilin sera (raised against denatured pili) also reacted with pilin from 2 of 3 heterologous strains. However, none of the patterns of staining or absorption of any of these sera matched the spectrum of cross-protection afforded by vaccination of sheep with B. nodosus strain 198 cells. The results question the role of individual OMC proteins in cross-protective immunity and may imply that interactions between several bacterial components are involved in the phenomenon. 相似文献
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《Veterinary microbiology》1998,59(4):283-294
F41-positive and F41-negative derivatives of bovine enterotoxigenic Escherichia coli strain B41 carrying K88 or K88 and K99 plasmids were investigated for stability and expression of genes for their fimbrial antigens. Either K88 plasmid alone or both K88 and K99 plasmids could be maintained in these strains though stability could depend on culture medium. K99 antigen could be detected in each strain bearing K99 plasmid. Clones that produced K88 antigen or clones that did not produce this antigen could be isolated from each strain, except from the strain that possessed K99 plasmid in the strain that did not possess the ability to produce F41 antigen. Strains possessing K88 plasmid in the strain able to produce F41 antigen produced clones expressing either both K88 and F41 antigens, (also F41 appeared strongly expressed in some clones) or clones that produced only F41 antigen or no antigen at all. Clones that produced only K88 antigen or others that did not produce this antigen could be produced from a strain bearing only K88 plasmid and that did not possess the ability to produce F41 antigen. None of these strains bearing K88 plasmid alone or additionally K99 plasmid produced mannose-resistant hemagglutination of horse or sheep erythrocytes at 20°C as found for K99 and F41 ETEC natural strains, respectively. These results suggested that the structures of pili when several genetic determinants were present simultaneously may not be identical to those of original strains. In this study, clones expressing either one, two or three adhesin bearing antigens could be obtained from the strain B41. 相似文献
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本研究以藏北嵩草（Kobresia littledalei）上附着的乳酸菌为研究对象，分离得到肠膜明串珠菌肠膜亚种两株，融合魏斯氏菌11株，食物魏斯氏菌6株，然后对这3种试验菌进行不同温度及pH条件下的生长试验、耐盐试验及糖发酵试验等生理生化特性的研究。结果表明，与常规条件下分离得到的相同菌株相比较，青藏高原极端环境中分离的魏斯氏乳酸菌和明串珠菌株都能在4~40 ℃的条件下生长，部分融合魏斯氏菌还可在50 ℃下微弱生长；耐酸碱试验表明，魏斯氏乳酸菌株都能在pH值为3.0和9.5的条件下生长；在耐盐性方面，部分魏斯氏菌可以在18%的NaCl下生长；在碳源利用方面，本研究提取的食物魏斯氏菌可利用半乳糖；融合魏斯氏菌可利用阿拉伯糖、蜜二糖、甘露醇。因此，藏北嵩草中所分离的乳酸菌比常规环境中的乳酸菌有较强的耐温性和耐酸碱性，而且能更广地利用碳源，从而为其在饲料青贮、酸奶发酵等方面的应用奠定基础。 相似文献
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本试验旨在探讨中草药体外抑菌作用,为纯中草药消毒剂的临床使用和扩大临床使用范围提供科学依据。本试验以金黄色葡萄球菌、大肠杆菌、沙门氏菌为模式菌株,以抑菌圈直径、抑菌浓度、细菌生长曲线和抑菌温度曲线为检测指标,研究纯中草药消毒剂"香连"溶液干膏剂的抑菌活性。试验结果显示,对3种模式菌株的抑杀效果由强到弱依次为金黄色葡萄球菌、大肠杆菌、沙门氏菌,MIC分别为7.81、31.25、250mg/mL,所需时间分别为2、2、6h,对金黄色葡萄球菌、沙门氏菌抑杀环境温度为25、37℃。结果表明,"香连"溶液消毒剂不仅可作为环境消毒剂,也可作为饮水消毒剂和细菌性疾病的治疗药物。 相似文献
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Immunity to toxoplasmosis in hamsters 总被引：1，自引：0，他引：1
Protective immunity to Toxoplasma was studied in hamsters. Immunity developed in 2 to 3 weeks after vaccinations were performed. Vaccination with live RH, T-45, and ts-4 strains afforded the best protection against challenge exposure with the most pathogenic RH strain used. Even a killed-toxoplasma vaccine protected all hamsters against the slightly less pathogenic T-1 strain through 24 weeks, but it did not protect hamsters against challenge exposure with the RH strain. Both ts-4, a nonpersistent strain, and killed-toxoplasma vaccine provided protective immunity in hamsters that was not dependent upon premunition. Toxoplasma antibody titers in hamsters given the 2 vaccines were similar. However, there was a difference in the quality of immunity: fever and body weight loss were seen in hamsters vaccinated with the killed-toxoplasma vaccine after they were challenge exposed with T-1 strain, whereas these changes were rarely seen in hamsters given the live-toxoplasma vaccine and then challenge exposed with RH strain. Delayed-type hypersensitivity to Toxoplasma antigen always appeared before protective immunity and was detected in all hamsters by 4 days after vaccination with live-toxoplasma strains. Although the development of delayed-type hypersensitivity preceded protective immunity, it was not indicative that protective immunity was present or would develop. 相似文献
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Chronic non-progressive pneumonia (CNP) is a common disease which affects lambs in New Zealand during late summer and autumn. Mycoplasma ovipneumoniae can be recovered from a high proportion of lesions but it is also present in some normal lungs. Bacteria, especially Pasteurella haemolytica, can also be recovered from more than half the lungs of affected animals. Isolates of M. ovipneumoniae are genetically heterogeneous, as demonstrated by examination of their DNA or total cellular proteins, and are serologically heterogeneous as shown by metabolic inhibition tests. The number of strains present in New Zealand is large and several distinguishable strains can be recovered from each affected lung. Mycoplasma ovipneumoniae has pathogenic potential as indicated by its ability to produce hydrogen peroxide, cause ciliostasis and by its possession of a capsule. Chronic non-progressive pneumonia can be transmitted consistently to over 50% of lambs by inoculation of pooled pneumonic lung homogenate and transmission can be suppressed by broad spectrum antibiotics. In contrast, penicillin does not prevent the development of lesions but diminishes their severity. Pooled lung homogenate treated with digitonin, which inactivates mycoplasmas, has failed to transmit CNP. Pure cultures of M. ovipneumoniae produce only mild lesions in some animals, whereas inoculation with pooled lung homogenate (from which no viruses were isolated) containing mixed strains of M. ovipneumoniae and free from bacteria, is more effective in producing lesions. Research work to date suggests that CNP may be initiated by colonisation of the lung by M. ovipneumoniae which causes ciliostasis and elicits an exudate allowing colonisation of the lungs by bacteria especially M. haemolytica and by other strains of M. ovipneumoniae. The immune response to the initial strain of M. ovipneumoniae may inhibit its replication but would be less effective in inhibiting heterologous strains of the organism allowing their sequential replication. Eventually production of a broad immune response to M. ovipneumoniae would lead to its elimination which in turn would facilitate the elimination of other microorganisms and the resolution of lesions. As natural immunity to CNP occurs within the first year, it may be possible to develop an effective and useful vaccine. Such a vaccine may need to include multiple strains of M. ovipneumoniae. 相似文献