犬中暑的急救与预防

犬中暑是炎热季节常发的一种急症,重度中暑一旦发生,往往来势急剧,如抢救不及时或措施不力,可导致病犬很快死亡。近年来,各地因犬中暑而造成死亡的屡有发生,尤其是训练作业犬多见。     

Interference Efficiency and Effects of Bacterium-mediated RNAi in the Fall Armyworm (Lepidoptera: Noctuidae)

RNAi is an effective tool for gene function analysis and a promising strategy to provide environmentally friendly control approaches for pathogens and pests. Recent studies support the utility of bacterium-mediated RNAi as a cost-effective method for gene function study and a suitable externally applied delivery mechanism for pest control. Here, we developed a bacterium-mediated RNAi system in Spodoptera frugiperda based on four target genes, specifically, Chitinase (Sf-CHI), Chitin synthase B (Sf-CHSB), Sugar transporter SWEET1 (Sf-ST), and Hemolin (Sf-HEM). RNAi conducted by feeding larvae with bacteria expressing dsRNAs of target genes or injecting pupae and adults with bacterially synthesized dsRNA induced silencing of target genes and resulted in significant negative effects on growth and survival of S. frugiperda. However, RNAi efficiency and effects were variable among different target genes and dsRNA delivery methods. Injection of pupae with dsCHI and dsCHSB induced a significant increase in wing malformation in adults, suggesting that precise regulation of chitin digestion and synthesis is crucial during wing formation. Injection of female moths with dsHEM resulted in lower mating, fecundity, and egg hatching, signifying a critical role of Sf-HEM in the process of egg production and/or embryo development. Our collective results demonstrate that bacterium-mediated RNAi presents an alternative technique for gene function study in S. frugiperda and a potentially effective strategy for control of this pest, and that Sf-CHI, Sf-CHSB, Sf-ST, and Sf-HEM encoding genes can be potent targets.     

我国农药质量监测体系建设的现状及展望

农药作为重要的农用生产资料,其质量的好坏直接影响着农业生产,但我国农药质量监督检测体系发展滞后,存在许多问题,影响了我国农药质量的提高。本文重点阐述了我国农药质量监测体系的现状、存在问题并对未来发展作出了展望。     

单抗对禽病原性大肠杆菌菌毛粘附抑制的研究

应用８株鸡病原性大肠杆菌研究了菌毛作为分型抗原和共粘附特性,以抗Ⅰ型菌毛单克隆抗体（单抗）ｂＧ５和甘露糖进行了抑制作用试验。在血凝试验中、单抗和甘露糖都能抑制血凝反应,说明这些株都属于Ⅰ型,通过以单抗或甘露糖的粘附抑制程序这些Ｅｃｏｌｉ株对鸡气管上皮都不能特异粘附。     

离体法在饲料复合酶配方筛选中的应用

通过模拟动物消化生理规律,采用胃蛋白酶盐酸溶液（ＰＰＳ）和猪小肠液（ＰＩＦ）两步处理为特点的离体法分别测定９种鸡复合酶饲料和９种猪复合酶饲料的能量消化率,从而筛选出最佳复合酶组织。结果表明,最佳鸡伺料复合酶组合为纤维素酶１号＋植酸酶２号＋蛋白酶３号＋淀粉酶２号,最佳猪伺料复合酶组合为纤维素酶３号＋植酸酶３＋蛋白酶３号。肉鸡伺养试验结果表明,最佳复合酶试验组较对照组平均日增重提高９．６０％,料肉比降低２６．１０％;仔猪伺养试验结果表明,最佳复合酶试验组较对照组平均日增重提高９．６０％,料肉比降低２６．１％;仔猪伺养试验结果表明,最佳复合酶试验组较对照组平均日增重增高１２．４７％,料肉比降低３．２１％。结果验证了离体法在筛选伺料复合酶组合中的可行性。     

水分胁迫对芒果成花效应及内源激素变化的影响

以３ａ生盆栽红芒６号为试材,研究水分胁迫对芒果成花的效应。发现水分胁迫能改变芒果植株梢尖内源激素的水平及激素间的平衡,使 ＧＡ减少,ＡＢＡ和 ＣＴＫ增加,ＣＴＫ／ＧＡ及ＡＢＡ／ＧＡ的比率提高,抑制营养生长,促进开花,成花率高达 ７５％;而对照（灌水）植株营养生长旺盛,萌发新梢,抽梢率３７．５％,成花率仅６．２５％。      

浅谈WTO对泵行业的影响

我国加入ＷＴＯ后,泵厂家将面临更大的挑战和机遇。小型农用泵和家用泵必须提高产品质量,利用价格优势,扩大在国际市场的销售;工业泵厂家应该在技术和理论,制造工艺,企业分工和管理方面提高自己,提高产品内在质量和外观,提高企业形象,提高竞争能力。总之,我国加入ＷＴＯ利大于弊。ＷＴＯ将促使泵行业寻求变革,寻求生存,并获得成长。     

透视日本进口食品安全监管制度

食品安全作为一个世界性问题,备受各国关注。日本作为发达国家,凭借自身强大的综合国力,在这一领域已形成一套完备监管体系。本文以日本食品安全管理组织机构、基本职能的阐述为切入点,在此基础上对其最具特色的进口食品安全检测体系进行了翔实分析,以期为中国食品安全监管体系的完善提供可借鉴经验。     

香菇双单杂交育种初步研究

选用香菇的一个野生株（Ｑ）与一个栽培株苏香（Ｓ）的４种孢子单核体进行双单杂交,获得四个杂交后代。栽培结果表明：１,２,４号菌株产量明显高于双亲产量,其中以２号菌株产量最高,其生物转化率为８６９１％,产量优势为２１２９％,３号菌株产量高于双核体亲本Ｑ,其杂种优势显著。     

Microbial biomass and activity along a natural pH gradient in forest soils in a karst region of the upper Yangtze River,China

Mountain closure, considered an effective and economic measure for natural restoration of degraded forest ecosystems, has been widely carried out in the karst region of southwest China. The aim of this study was to evaluate microbial aspects of soil quality after mountain closure by analyzing soil microbial biomass, basal respiration, metabolic quotient, and relationships with basic chemical properties in Guizhou Province, a karst region of the upper Yangtze River. Soil quality was considered poor from the low levels of microbial biomass carbon (MBC), nitrogen (MBN), and microbial quotient (MBC/total C and MBN/total N), but high metabolic quotient (qCO₂). Soil pH, showing marked variation from 4.1 to 7.9 in this karst region, was proved to significantly affect soil microbial biomass and activity. Soil microbial biomass, microbial quotient, and soil basal respiration declined significantly with decreasing soil pH, while qCO₂ showed an apparently increasing, but not statistically significant, trend. The changes in microbial biomass and activity following the change in soil pH could possibly be because of a change in soil microbial composition, and more detailed research is necessary. Compared with soil pH, soil organic matter content was another, more important, factor that directly restricted microbial growth because of the serious loss as a result of disturbance. As a practical application based on microbial aspects, introduction of some N-fixing tree species may be an active and effective measure to improve soil fertility and thus to accelerate restoration of the forest ecosystem in the karst region.