猪繁殖与呼吸综合症病毒单克隆抗体的制备和鉴定

以猪繁殖与呼吸综合征病毒（PRRSV）作为免疫原,免疫BALB／c小鼠,经间接ELISA、IPMA和IFA试验进行杂交瘤筛选,共获得2株能分泌针对PRRSV单克隆抗体（简称单抗）的杂交瘤细胞株,分别命名为3D10和4H11,3D10亚类为IgG1,4H11亚类为IgG2b,单抗腹水的间接ELISA效价均达到1．0×10^7,染色体数目介于90～110之间。2株单抗与猪细小病毒、猪伪狂犬病毒、猪圆环病毒2型均无交叉反应,IPMA和IFA结果显示单抗均能与接种于猴肾细胞（Marc145）的PRRSV发生特异性反应,证实抗PRRSV单抗具有良好的特异性和敏感性,为PRRSV抗原表位分析及相关抗原抗体诊断试剂盒的研制奠定了基础。     

凉山皮寒药药效初探

为了探讨凉山皮寒药抑菌、抗炎、调节免疫及抗疲劳的效果,本研究进行了抑菌试验、二甲苯致小鼠耳廓肿胀试验、免疫相关试验及负重游泳试验.结果表明,凉山皮寒药水针剂对选用了6种细菌具有一定的抑菌效果;能使小鼠耳廓肿胀度明显降低,与空白对照组比较,高、中剂量组均差异极显著(P＜0.01),低剂量组差异显著(P＜0.05);对小鼠T淋巴细胞有增值的趋势;能增加脾脏指数;能极显著延长小鼠负重游泳的时间(P＜0.01).结果提示,凉山皮寒药水针剂对部分革兰阳性和阴性菌有一定抑制作用,对小鼠耳廓肿胀有明显的抑制作用,能增强小鼠免疫力与抗疲劳能力.     

荧光定量RT-PCR检测公猪精液和血液中猪瘟病毒载量

为快速检测规模化猪场猪瘟病毒(Classical swine fever virus,CSFV),本研究参考GenBank中登录的CSFV序列设计引物,利用实时荧光PCR技术,构建重组质粒作为阳性标准品,建立特异、敏感、重复性好的CSFV快速定量检测方法.同时建立标准曲线,用于对猪瘟病毒的定量分析.本方法对规模化猪场的100份抗凝血和50份公猪精液样品进行检测,常规PCR检出27份占18％,荧光定量PCR检出123份占82％.表明荧光定量RT-PCR方法在检测猪瘟样品中具有潜在的应用价值,同时可检测猪群中猪瘟病毒持续性感染的状态存在.     

肉毒杆菌及肉毒毒素研究进展

肉毒杆菌是一种致命病菌,能引起肉毒中毒症。肉毒杆菌作为影响食品安全的一个重要风险因素,尤其是在新西兰恒天然公司部分产品受到肉毒杆菌污染事件发生后,肉毒杆菌及肉毒毒素受到了普遍关注。现就肉毒杆菌及肉毒毒素的生物学特性、中毒机制、诊断及治疗研究进展进行综述。     

A developmental profile of tocol accumulation in oat seeds

Oats are a good source of many vitamins and minerals, including compounds that collectively constitute vitamin E, the tocols. Tocols are comprised of two subgroups, tocopherols and tocotrienols. Due to their potent antioxidant properties, attention has been given to the health benefits of tocols in oats. However, little is known about developmental aspects of their accumulation. Moreover, aside from their role in protecting membranes from oxidative damage, their possible physiological roles in planta have largely gone uninvestigated. In this study, we quantified tocol accumulation at five time points during oat seed development, and also compared tocol concentration and composition in the whole seed both to endosperm and embryos at a late stage of seed development. The temporal pattern of accumulation of the tocol subgroups was different. Both tocotrienols and tocopherols steadily increased over the course of seed development; however, tocotrienol progression was sigmoidal and tocopherol linear. By the end of seed development, tocotrienols were the most abundant tocol both in whole seed and in seed with embryos removed. In contrast, embryos contained higher concentrations of tocopherols than tocotrienols late in seed development. Differences in both temporal and spatial distribution during seed development suggest distinct roles for tocotrienols and tocopherols.     

Simultaneous Extraction and Depolymerization of Fucoidan from Sargassum muticum in Aqueous Media

The biomass components of the invasive seaweed Sargassum muticum were fractionated to allow their separate valorization. S. muticum (Sm) and the solid residue remaining after alginate extraction of this seaweed (AESm) were processed with hot, compressed water (hydrothermal processing) to assess the effects of temperature on fucoidan solubilization. Fucose-containing oligosaccharides were identified as reaction products. Operating under optimal conditions (170 °C), up to 62 and 85 wt% of the dry mass of Sm and AESm were solubilized, respectively. The reaction media were subjected to precipitation, nanofiltration and freeze-drying. The dried products contained 50% and 85% of the fucoidan present in Sm and AESm, respectively; together with other components such as phenolics and inorganic components. The saccharidic fraction, accounting for up to 35% of the dried extracts, contained fucose as the main sugar, and also galactose, xylose, glucose and mannose. The concentrates were characterized for antioxidant activity using the TEAC assay.     

披碱草属野生种质材料在干旱与半干旱区适应性评价

应用灰色理论系统,以搜集自我国8省区的38份披碱草属植物野生种质材料为研究对象,对其株高、叶面积生长动态、草产量、茎叶比、鲜干比及种子产量进行灰色关联度分析.结果表明,株高从拔节期到抽穗期增幅较大,而叶面积从分蘖期到拔节期增幅较大;38份材料鲜草及干草产量差异较大,变异系数分别为39.275％和43.087％;大部分种质材料茎叶比在1.0～2.0之间;不同材料种子产量的变异系数较大;产量与各主要农艺性状的关联度大小顺序为:鲜干比＞种子产量＞茎叶比＞叶面积＞株高.综合分析发现,适应性较好的种质材料有NMC32、BJT37、QHD19、SXD36、XJD11、XJD15、XJS8、XJT2、XJE13和XJD5.     

养猪场户对生猪良种补贴政策满意度影响因素分析

作为补贴对象和直接受益者,养猪场户对政策的满意程度直接影响到政策的实施情况及效果,同时也是政策进一步调整优化时需要考虑的重要因素。本文基于养猪场户的调研数据,通过构建Logit模型,分析影响养猪场户对生猪良种补贴政策满意度评价的主要因素,结果发现:从事养猪年限、对人工授精技术掌握程度、对供精单位技术服务满意度、对供精单位配送服务满意度、对生猪良种补贴政策了解程度等因素对养猪场户的满意度评价有显著影响。     

加热回流法和超声波法提取淫羊藿苷的试验研究

以乙醇为提取溶剂,采用加热回流法和超声波法从淫羊藿中提取淫羊藿苷,采用单因素试验考察提取次数、提取时间、料液比和乙醇体积分数对提取率的影响,并设计正交试验优化提取工艺.结果表明,优化的加热回流法为料液比1∶10(m∶V,g/mL)、提取2次、提取时间40 min、乙醇体积分数75％;优化的超声波法为乙醇体积分数60％、超声提取时间30 min、提取1次、料液比1∶6(m∶V,g/mL).