蛋白质饲料木聚糖含量及其体外酶解效果研究

本文通过体外酶解试验,考察木聚糖酶对豆粕、菜籽粕和棉籽粕的总木聚糖和水溶性木聚糖的降解效果,试图建立木聚糖酶与不同蛋白质饲料种类的定量关系.试验结果表明:①不同蛋白质饲料的总木聚糖和水溶性木聚糖的含量不同,豆粕、菜籽粕和棉籽粕的总木聚糖含量分别为5.62%、6.56%和8.20%;水溶性木聚糖含量分别为0.35%、0.97%和0.84%;②不同来源的3种蛋白质饲料的总木聚糖和水溶性木聚糖含量变异较小.在适宜的水环境中,菜籽粕的水溶性木聚糖含量显著增加,豆粕和棉籽粕的水溶性木聚糖变化不大;③木聚糖酶对3种蛋白质饲料的总木聚糖均有显著降解作用,对水溶性木聚糖有一定的降解作用,其中对菜籽粕的总木聚糖和水溶性木聚糖的降解作用均较大;以总木聚糖酶为标识,结合考虑成本,豆粕、菜籽粕、棉籽粕的适宜添加木聚糖酶水平分别为1 000、1 000和1 500 U/kg.     

Immunoadjuvant effects of hemagglutinating virus of Japan envelope (HVJ-E) on the inactivated H9 subtype avian influenza virus vaccine

Avian influenza viruses (AIV) of the H9 subtype cause serious health problems in chickens, resulting in great economic losses to the poultry industry worldwide. The killed vaccine (KV) against H9 subtype AIV has been widely used in China since 1998 but has been linked with side effects in chickens and only partial protection. A few studies have demonstrated the immunostimulatory effects of the hemagglutinating virus of Japan envelope (HVJ-E) in cancer therapy. In this study, the adjuvant efficacy and the protective effects of HVJ-E, in combination with H9N2 AI KV against AIV were evaluated. The maturation of murine dendritic cells treated by HVJ-E was verified by FACS in the current experiment, then the antibody hemagglutination inhibition (HI) titers and cytokines and the post-challenge virological profiles (oropharyngeal and cloacal virus shedding) were investigated to define the immune responses in chickens. Our findings indicate that HVJ-E could induce dendritic cell (DC) maturation in mice. Injection of HVJ-E in chickens resulted in raised levels of IFN-β and IFN-γ being present in sera suggesting a stimulatory effect in these animals. The antibody responses to AIV of chickens inoculated with HVJ-E adjuvanted killed H9-AIV were higher than those of chickens inoculated with oil adjuvanted H9-HIV. Furthermore, although inoculation of either HVJ-E or oil adjuvanted AIV reduced virus shedding following challenge, compared to controls, HVJ-E adjuvanted AIV was more effective in reducing shedding than oil adjuvant.     

犬瘟热病毒的静水压灭活

以250MPa的静水压力对犬瘟热病毒（CDV）处理30min之后，CDV被灭活，由其制成的灭活疫苗诱导犬产生中和抗体的能力明显优于传统的福尔马林灭活疫苗，免疫保护率达90％。电镜观察显示，经不同程度静水压力处理后的CDV粒子均发生变形，表面呈现凸起，但CDV H基因部分片段的RT－PCR扩增结果揭示，高达510MPa的静水压力作用30min也未能使其基因片段受到破坏。     

Microarray-based detection of viruses causing vesicular or vesicular-like lesions in livestock animals

Definitive diagnosis of vesicular or vesicular-like lesions in livestock animals presents challenges both for veterinary clinicians and diagnostic laboratories. It is often impossible to diagnose the causative disease agent on a clinical basis alone and difficult to collect ample vesicular epithelium samples. Due to restrictions of time and sample size, once laboratory tests have ruled out foot-and-mouth disease, vesicular stomatitis and swine vesicular disease a definitive diagnosis may remain elusive. With the ability to test a small quantity of sample for a large number of pathogens simultaneously, DNA microarrays represent a potential solution to this problem. This study describes the application of a long oligonucleotide microarray assay to the identification of viruses known to cause vesicular or vesicular-like lesions in livestock animals. Eighteen virus isolates from cell culture were successfully identified to genus level, including representatives of each foot-and-mouth disease virus serotype, two species of vesicular stomatitis virus (VSV), swine vesicular disease virus, vesicular exanthema of swine virus (VESV), bovine herpesvirus 1, orf virus, pseudocowpox virus, bluetongue virus serotype 1 and bovine viral diarrhoea virus 1. VSV and VESV were also identified in vesicular epithelium samples, with varying levels of sensitivity. The results indicate that with further development this microarray assay could be a valuable tool for the diagnosis of vesicular and vesicular-like diseases.     

空肠弯曲菌耐药机制研究进展

空肠弯曲菌是一种全球关注的人兽共患病病原菌,由于滥用抗生素而造成其耐药性不断增强,成为公共卫生日益关注的问题.各类抗生素作用位点的基因突变是诱发空肠弯曲菌对各类临床常用的抗生素产生耐药的主要原因,同时细菌对药物的外排机制也在其对抗生素耐药过程中发挥了一定的作用.文章对空肠弯曲菌对各类临床常用抗生素的耐药机制做一综述.     

猪囊尾蚴囊液抗原制备及ELISA检测条件的优化

本试验采用SephadexG-200层析技术纯化猪囊尾蚴（Cysticercus cellulosae）的囊液粗抗原。共获得两种（CF1、CF2）层析抗原，以酶联免疫吸附试验（ELISA）判定抗原的最适包被浓度以及抗体的最适稀释倍数，各阶段最适反应条件，结果证明CF1具有特异性强、敏感性高、稳定性好、重复性强的特点可以作为免疫诊断囊尾蚴病猪IgG。     

微生物发酵中药的研究现状及其在养殖业中的应用

发酵法是中药炮制的传统方法,具有提高有效成分含量、增强或产生新的疗效、降低毒性、调整肠道菌群等作用。现代中药发酵技术克服了传统中药发酵技术的菌种驳杂、温度和湿度不可控等缺点,发展出了固体发酵、液体发酵和双向固体发酵的现代工艺技术。近年来国家推行饲料禁抗,微生物发酵中药作为一种微生态制剂,在提高动物生产性能、提高动物机体免疫力、预防和治疗疾病等方面,以其独特的优势成为养殖业中抗生素替代品之一,在畜禽养殖业和水产养殖业有着巨大的潜力和市场。但目前发酵中药仍存在发酵机理不明确、物质基础的改变相对未知、发酵菌种较为单一、缺少一定的质量标准等问题。作者重点介绍了发酵中药的优势并比较了各种发酵技术的优点和缺点,对发酵中药在畜禽养殖和水产养殖中的应用进行了归纳总结,分析了发酵中药的发展潜力以及目前存在的问题、改进方案及发展方向,以期对未来微生物发酵中药的深入研究及其在畜禽、水产养殖业中的应用提供思路与借鉴。     

遥感技术在松嫩平原西部半干旱区扎龙湿地调水中应用研究

黑龙江扎龙自然保护区是我国最大的以鹤类等大型水禽为主体的珍禽鸟类和湿地生态类型的国家级自然保护区。为了迅速查清2001年4月至2002年7月间先后两次对扎龙湿地调水情况,我们采用了美国陆地卫星影像Landsat-ETM对调水前后四个时相进行了解译,在GIS支持下,结合扎龙遥感野外验证对扎龙湿地变化进行了科学分析,在较短时间内取得了可靠数据,为下一步扎龙湿地水资源规划提供了科学依据。     

木聚糖酶对肉鸡能量饲料养分利用率和表观代谢能值的影响

本试验通过肉鸡代谢试验考察木聚糖酶对玉米、小麦、麦麸和米糠的养分利用率和表观代谢能(AME)值的影响,确定木聚糖酶与不同能量饲料的定量关系.试验包括4个单因子试验,分别用玉米、小麦、麦麸、米糠进行代谢试验,每种饲料设5个处理,添加不同水平木聚糖酶,每个处理8个重复,每个重复1只鸡.试验结果表明:对于玉米,当木聚糖酶添加水平为1 500 IU/kg时,与对照组相比,干物质利用率提高了0.93%(P<0.05).对于小麦,木聚糖酶水平为3 000 IU/kg时,干物质、能量和蛋白质利用率提高幅度最大,分别提高了7.02%(P<0.01)、6.78%(P<0.01)和22.31%(P<0.05).对于麦麸,在木聚糖酶为6 000 IU/kg时,干物质和能量利用率提高幅度最大,分别提高10.14%和14.73%(P<0.01);在木聚糖酶为4 000 IU/kg时,蛋白质利用率提高157.31%(P<0.01).对于米糠,在酶水平为1 500 IU/kg时,米糠的蛋白质利用率提高了27.92%(P<0.05).适宜水平的木聚糖酶显著提高了小麦、麦麸的AME值.结果表明,玉米、小麦、麦麸、米糠中每克总木聚糖的适宜木聚糖酶添加量分别为35.38、27.01、30.21和18.27 IU,每克水溶性木聚糖的适宜木聚糖酶添加量分别为1 250、273.56、753.33和937.5 IU.     

氧化塘深度对猪场厌氧消化液后处理的影响

采用小试装置对3个不同深度氧化塘处理猪场厌氧消化液的效果进行了研究,结果表明:当平均气温为21.9℃,停留时间在80 ～110天,进水负荷为0.05 m3·m-2d-1的条件下,氧化塘对NH4-N的去除率达到了90％以上,CODcr,TP的去除率分别为50％,40％.硝化作用和藻类的吸收是氧化塘去除NH4-N的主要方式,沉淀作用则是CODcr和TP的主要去除方式,在较长停留时间下,微生物对于溶解性CODcr的分解和同化也能提供一定的去除效果.当平均气温为21.9℃,在表面负荷为0.05 m3·m-2d-1的条件下,有效深度为0.3m和0.7m的氧化塘面积去除负荷分别为1.41 g·m-2d-1,1.49 g·m-2d-1,容积去除负荷分别为4.7g·m -3d-1,2.8g·m-3d-1.虽然较深氧化塘具有较高的面积去除负荷,但较浅的氧化塘却有更高的容积去除负荷.