Oral immunization using formalin-inactivated Actinobacillus pleuropneumoniae antigens entrapped in microspheres with aqueous dispersion polymers prepared using a co-spray drying process

Oral-vaccine microspheres based on formalin-inactivated Actinobacillus pleuropneumoniae serotype 1 (AP-1) antigens and enteric-coated polymers were prepared using a co-spray drying process. We evaluated using this for a peroral vaccine. We measured specific-antibody titers and protection from challenge in mouse and pig models. In mice (24 per group), a subcutaneous aluminum-adjuvant vaccine or oral vaccination with three doses of AQ6-AP microspheres provided similar protection against intranasal challenge with 5 x 10(8) colony-formation units (cfu) of AP-1 bacterial culture broth. Two weeks after four oral vaccinations with 600 mg of AQ6-AP microsphere acetate solution (containing formalin-inactivated AP-1 antigens of 1.0 x 10(10) cfu bacterial broth), pigs (9 per group) were challenged intranasally with 1 ml of AP-1 bacterial culture broth (5 x 10(9) cfu). The clinical signs, percentage of pig survival ratio, lung lesion areas, and microscopic examinations indicated that the oral AQ6-AP vaccine provided more protection than vaccinating pigs intramuscularly with AP-1 aluminum vaccine.     

稻草与氨化稻草干物质采食量的模型化研究

本研究分别以稻草、氨化稻草为唯一能量和蛋白质来源,实测了山羊稻草、氨化稻草的干物质采食量(DMI),并借鉴现有成熟模型,建立了以稻草、氨化稻草的中性洗涤纤维(NDF)为预测因子的干物质采食量预测模型:DMI稻(g/d.kgMW)=30/NDF(%DM),DMI氨稻(g/d.kgMW)=39/NDF(%DM)。经验证,稻草、氨化稻草DMI预测模型的平均偏差(MD)分别为0.48g/d.kgMW与0.85g/d.kgMW,相应的平均预测方差(MSPE)为0.3599与1.0124。稻草与氨化稻草的MD、MSPE均很低,表明所建DMI预测模型精确可用。     

天津市武清区秸秆综合利用现状及问题

积极探索秸秆的综合利用途径,大力推进秸秆资源化利用,发挥其应有的经济、生态、社会和环境效益,对保持社会协调、稳定发展,推进农村新能源建设,保障社会经济生活的正常秩序,具有重要的政治、经济和社会意义。在介绍秸秆利用价值的基础上,分析了天津市武清区秸秆利用现状和存在的问题,并提出相关的建议措施,以推进秸秆的综合利用进程。      

应用套入式聚合酶链反应(Nested-PCR)检测蓝舌病病毒的研究

本实验建立了一种Ｎｅｓｔｅｄ－ＰＣＲ方法。应用方法检测５株标准株蓝舌病病毒（Ｔ４、Ｔ１０、Ｔ１１、Ｔ１６、Ｔ２０）和５株国内蓝舌病病毒分离株（ＣＦ４、ＡＦ６、Ｚ１、Ｈ１、Ｇ１４）,检测结果均为阳性,而检测相关环状病毒（ＥＨＤ２、ＥＨＤ６、Ｉｂｒａｋｉ）,检测结果均生。研究证明,此方法可检测到３．５ｆｇ的ＢＴＶ－ＲＮＡ,灵敏度较高。该方法成功区分了蓝病病毒和相关环状病毒,比血清学方法更加优势,在临床     

光棘豆单细胞培养再生植株

由光棘豆种子无菌苗的胚轴和子叶诱导的愈伤组织建立起细胞悬浮系。由悬浮系分离出单细胞。单细胞在含有1～2mg/L 2,4—D的2/3MS培养基中采用振荡和静止两种方法培养。结果表明。振荡培养愈伤组织再生频率较高,所需时间较短。单细胞再生的愈伤组织转入分化培养基后分化出芽。幼苗转入含有IBA和IAA的1/2MS培养基中生根,成为完整的再生植株。在分化培养基中,只有瘤状愈伤组织能够分化出芽。并且较高浓度的细胞分裂素(6—BA或KT)或6—BA与ZT结合使用对愈伤组织的分化是有利的。     

不同水钙磷浓度条件下草鱼对水和饲料中钙磷的吸收利用

本研究结果表明:草鱼对饲料钙磷的消化吸收受水中钙磷浓度的影响。草鱼能直接从水中吸收利用钙磷。鱼体存积的大部分来自于水,而磷则大部分从饲料中获得,草鱼钙磷的利用按Ca/P≈1.6的比值进行。     

刚棘颚口线虫的扫描电镜观察

刚棘颚口线虫扫描电镜显示：头球顶端有两片半球形的大侧唇，大侧唇背面有1对双乳突和1个头感器。在轮节皮棘第6-7排或第8-9排或第10-11之间各有1对颈乳突，与樊氏等及古贺正崇等描述颈乳突位置有所差异。并观察到雄虫尾端长交合刺的皮纹上有细小的凹陷小乳，其顶端有开口处；有2对尾乳突。雌虫阴门位于虫体腹面中线之后；尾端前腹面有半月状的肛门，有1对尾乳突。其中头钩、体棘、交合刺和尾乳突等形态特征与前人记述相似。     

Development of a loop-mediated isothermal amplification assay for rapid, sensitive and specific detection of a Campylobacter jejuni clone

Loop-mediated isothermal amplification (LAMP) assay is a simple, rapid and specific detection method and has been used for detection and identification of different Campylobacter species. In this study, we develop a LAMP assay specific for detection of a particular clone (clone SA) of Campylobacter jejuni, associated with the vast majority of recent sheep abortions in the U.S. Using a set of specific primers for C. jejuni IA3902 (a clone SA isolate) and genomic DNA or boiled cell extract as template, the target DNA was amplified at 63 °C for 50 min in a water bath. A positive reaction was identified visually as white precipitate or fluorescence under UV, and confirmed by gel electrophoresis. Detection limit of the assay was comparable to that of conventional PCR. The LAMP was shown to be specific for detection of clone SA when tested on a number of C. jejuni strains of different genetic backgrounds. Applicability of the LAMP assay for specific detection of clone SA was demonstrated in animal tissues experimentally infected with IA3902 or genetically diverse C. jejuni strains. Since clone SA is the predominant cause of sheep abortions in the U.S. and is a zoonotic pathogen, the LAMP assay may be a valuable detection tool in future epidemiological studies.