口蹄疫灭活疫苗中蛋白质含量测定方法的比较

口蹄疫灭活疫苗中蛋白质含量的测定,可以反映出疫苗生产工艺的优劣以及疫苗质量。采用凯氏定氮法、改良Lowry法和考马斯亮蓝法三种较常见的蛋白质含量测定方法,对全国六个不同口蹄疫灭活疫苗生厂家共计15批疫苗的总蛋白质含量进行测定,并对测定结果进行比较,同时采用SDS—PAGE对样品中蛋白质含量进行定性,验证以上三种方法测定结果。结果表明,这些疫苗的总蛋白质含量差异比较大,1mL水相样中蛋白质含量在50—2000μg范围内。三种检测方法比较表明,改良Lowry法能较真实的反映口蹄疫灭活疫苗中蛋白质含量;与凯氏定氮法相比,此方法操作简单,工作效率高,而且低耗。     

甘草多糖提取工艺的研究及其对小鼠免疫口蹄疫疫苗后细胞免疫的影响

以优化甘草多糖的提取工艺及开发其有效成分的药用价值为研究目的。本研究采用水提醇沉、膜提取法2种工艺提取甘草中有效成分甘草多糖(GPS)并测定其含量,以筛选最佳的提取工艺。研究不同工艺条件下提取的甘草多糖对小鼠脾脏淋巴细胞增殖的影响、以及口服用于猪O型口蹄疫疫苗免疫后的小鼠,检测血中IL-2、IL-6含量,观察甘草多糖(GPS)对小鼠细胞免疫功能的影响。结果显示膜提取法对甘草多糖提取效果最好(P0.05);在静止态淋巴细胞增殖试验中,所表现出的促增殖作用强于甘草多糖其他各组(P0.05);GPS-2组也能升高口蹄疫疫苗免疫后小鼠血液中IL-2、IL-6含量(P0.05)。     

Risk assessment and cost-effectiveness of animal health certification methods for livestock export in Somalia

Livestock export is vital to the Somali economy. To protect Somali livestock exports from costly import bans used to control the international spread of disease, better certification of livestock health status is required. We performed quantitative risk assessment and cost-effectiveness analysis on different health certification protocols for Somali livestock exports for six transboundary diseases.     

江门市规模化奶牛场2018—2019年O型、A型和亚洲Ⅰ型口蹄疫免疫抗体监测结果分析

[目的]为了解江门市规模奶牛场口蹄疫免疫情况,有针对性开展防控。[方法]在2个规模奶牛场中随机监督采集奶牛血清进行检测,根据国标用ELISA法检测O型口蹄疫抗体,用液相阻断ELISA法检测A型和亚洲Ⅰ型口蹄疫抗体。[结果]240份样品中O型、A型和亚洲Ⅰ型口蹄疫抗体合格率依次为99.6%(239/240),92.9%(223/240),81.7%(196/240),差异显著(P<0.01);但A场2019年亚洲Ⅰ型合格率仅65.0%(39/60),未达农业农村部规定的70%标准,以及B场2018年亚洲Ⅰ型合格率仅71.7%(43/60);其他项目合格率均在80%以上。[结论]江门市规模奶牛场口蹄疫总体免疫效果较好,奶牛群能得到有效保护,但亚洲Ⅰ型合格率相对偏低,相应场应加强免疫和检测。     

O型FMDV VP1基因与山羊IL-18基因在昆虫细胞中的共表达与活性检测

以杆状病毒pFastBacTM Dual为载体,将O型口蹄疫病毒(FMDV)VP1基因和山羊白介素18(gIL-18)基因,分别插入到双表达载体的P10启动子和多角体蛋白启动子PH的下游,构建重组质粒pFastBacTMDual-gIL18-VP1,然后转化DH10Bac感受态细胞,经三重抗性与蓝白斑筛选,获得杆状病毒重组质粒Bacmid-gIL18-VP1,并利用昆虫细胞进行转染。间接免疫荧光试验(IFA)检测表明gIL-18基因和VP1基因同时在同一细胞中独立表达。将共表达产物进行生物学活性分析表明,重组蛋白能够诱导山羊脾淋巴细胞生成IFN-γ抑制水疱性口炎病毒(VSV)在牛肾细胞(MDBK)上生长。本试验用Bac-to-Bac系统成功构建了同时含有gIL-18基因和VP1基因的重组杆状病毒,并在昆虫细胞中得到了高效表达,且具有良好的生物学活性,从而为下一步研究gIL-18在口蹄疫(FMD)中的免疫调节作用奠定了坚实的基础。     

Impact of foot-and-mouth disease on pork and chicken prices in Central Luzon,Philippines

Central Luzon is the number one pig-producing region in the Philippines and was affected by Foot-and-Mouth disease (FMD) in 1995. In this paper, the impact of FMD on the Central Luzon meat market from 1995 to 1999 was examined. Employing the error correction model (ECM) and historical decomposition, the impact of FMD on the Central Luzon pork and chicken meat market was quantified. The following findings were observed: (a) pig farm and pork wholesale prices dropped 11.8% and 15.7%, respectively, after the initial FMD outbreaks in January, 1995; (b) in February, 1995, chicken farm and wholesale prices declined by 21.1% and 14.2%, respectively (while chicken retail prices also went down by 10.5%); (c) the margins of pig and chicken traders were also adversely affected at some point; and (d) FMD caused changes of dynamic interdependence among prices by meat type at different levels of the meat supply chain.     

牦牛O型口蹄疫免疫程序研究

本试验对牦牛犊的母源抗体消长情况进行了分析,并对牦牛注射同种疫苗(不同免疫间隔和次数)后产生的免疫抗体进行了检测,旨在探寻牦牛口蹄疫最佳免疫程序。结果显示:牦牛犊母源抗体水平在15日龄后逐渐降低,至60日龄降到临界值附近;成年牦牛在首次免疫后2周进行加强免疫,口蹄疫抗体滴度明显更高。因此,建议牦牛犊在60日龄进行O型口蹄疫首免,2周后再加强免疫一次。     

Saponin Adjuvants. IV. Evaluation of The Adjuvant Quil a in the Vaccination of Cattle Against Foot-And-Mouth Disease

The saponin adjuvant Quil A has been investigated in the vaccination of cattle against foot-and-mouth disease. Using a Frenkel type vaccine a dose-response relationship has been established between Quil A and neutralizing antibody titres. Ten ml of vaccine was combined with 0, 50, 200, 800, and 3200 µg of Quil A. The combinations were each injected into 4 animals. The local reaction on the site of injection produced by injection of the vaccine alone and in combination with different doses of Quil A has been estimated. On this basis a therapeutical dose at 1 mg of Quil A has been estimated to combine maximum adjuvant effect with a minimum of adverse reactions. This dose has been tested in the vaccination of cattle with FMD vaccines derived from BHK suspension cell virus of type O and A respectively. The vaccines were tested in 10 ml and 5 ml doses with or without Quil A, and each in 4 animals. It is concluded that Quil A is a valuable adjuvant for use in the induction of neutralizing antibodies against foot-and-mouth disease in cattle.     

口蹄疫A型病毒AF/72株参考血清的研制

[目的]研制口蹄疫A型病毒AF/72株参考血清,筛选对实际防疫更具针对性的A型FMD标准血清,为研发安全高效优质的A型FMD疫苗提供实物支撑。[方法]用国家口蹄疫参考实验室提供的口蹄疫A型病毒AF/72株的第12代细胞毒AF/72/MF6-BF12,经测定并经Kaber法计算其TCID50为10-8.0/ml;经紫外分光光度法测定其146 S含量,均值为189.0 ng/ml,远大于22.0 ng/ml的国际标准。将此细胞毒与弗氏佐剂联合制成灭活疫苗免疫豚鼠后分离得到血清。[结果]经物理性状检验、无菌检验和外源病毒检验,纯净性符合兽用生物制品标准要求;参照国际标准血清的抗体效价测定方法ELISA和微量细胞中和试验检测了此血清的抗体滴度,原血清,强阳性血清和弱阳性血清的中和效价均远小于1∶45,符合标准的要求。[结论]对比国际口蹄疫参考血清的抗体滴度确定强阳性血清为口蹄疫A型病毒AF/72株的参考血清,为以后筛选抗原谱广的制苗毒株提供实物支撑。     

3种疫苗单独和联合免疫对猪抗体水平的影响

{目的]寻求有效结合注射的新型免疫程序,以有效控制猪瘟（CSF）、猪口蹄疫（FMD）和猪繁殖与呼吸综合征（PRRs）疫情的发生和流行[方法]在陕西省横山和米脂两县将140头猪随机分为7组,每组20头,采用CSF活疫苗（脾淋源）、FMD灭活疫苗（0型Ⅱ）、PRRS灭活疫苗（NVDC—JXA1株）分别进行单独、2种及3种同时分．点免疫注射试验,用正向间接血凝和EUSA法检测猪抗体水平。l结果10）3种疫苗都可以刺激猪产生特异性抗体,并且抗体在21、28和35d呈规律性增长。②CSF疫苗与FMD、PRRS疫苗分开和三者同时使用时．虽然FMD、PRRS疫苗推迟CSF抗体的上升时问,但是对CSF的免疫效果产生的影响不明显。（3）PRRS与FMD疫苗同时注射后,所产生抗体效价在21、28和35d均比单独注射PRRS疫苗阳性率高,说明FMD疫苗可对PRRs疫苗注射后有效抗体的产生达到积极协同作用,促进PRRS有效免疫抗体的产生,同时免疫CSF疫苗和PRRS疫苗的抗体水平低于单独注射PRRS疫苗,说明共同免疫CSF和PRRS疫苗时,2种疫苗会相互影响,使免疫效果不如单独免疫。④FMD和PRRS疫苗同时注射后,FMD疫苗所产生的抗体水平（OD值）最高,且一直呈上升趋势,优于FMD疫苗单独注射所产生的抗体水平,说明FMD和PRRS疫苗同时注射,更能促进FMD抗体的产生．[结论]3种疫苗同时分点注射和单注CSF产生抗体后再同时分点注射FMD和PRRS都是较好的防疫体系,具体应根据养殖规模及地域选择合适的防疫体系.