动物骨粉的应用研究

动物骨头是肉类加工的副产品，由于富含蛋白质，钙、磷等微量元素以及多种维生素等营养成分，具有较高的营养价值，其对动物生产性能的促进作用早已被人们所认知，将其加工为骨粉后用于畜牧养殖已在生产实践中大量利用。了解骨粉的营养特性，掌握骨粉的加工及应用方法，将有助于充分发挥骨粉的营养功效，提高骨粉的利用价值。     

Field evaluation of insect-resistant transgenic Populus nigra trees

The performance of insect-resistant transgenic poplar trees (Populusnigra) expressing a Cry1Ac gene from Bacillus thuringiensis subsp. Kurstaki HD-1 against poplar defoliators was evaluated in the field at the Manas Forest Station in Xinjiang Uygur Autonomous Region during1994–1997. The results showed that the average percentage of highly damaged leaves on the transgenic trees was 10% while that on the control trees in nearby plantations reached 80–90%. The average number of pupae per m² of soil at 20cm depth in transgenic poplar plantation was 18 which was only 20% of that found in the non-transgenic control field. The number of pupae and the leaf-damage on transgenic trees described above are all far below the threshold set for chemical protection measures. The non-transformed poplar trees grown in the same plantation with the transgenic trees were also protected indicating that cross protection occurred between these two kinds of trees. Insect-resistant transgenic poplar trees have a potential application value in afforestation. This revised version was published online in August 2006 with corrections to the Cover Date.     

Effect of stachyose supplementation on growth performance, nutrient digestibility and caecal fermentation characteristics in broilers

1. The objective of this study was to evaluate whether the oligosaccharide stachyose enhances gastrointestinal tract health by fermentation and proliferation of desirable bacteria species and thus affects growth performance and nutrient digestibility in broilers. 2. A total of 432 1-d-old male Arbor Acres (AA) broilers were randomly allocated to one of 6 treatments, with 12 replicate pens per treatment and 6 birds per pen. Chicks were fed a maize-hamlet protein 300 (HP300) basal diet with 0, 4.0, 8.0, 12.0 or 16.0 g/kg stachyose. A sixth diet contained no HP300 but soybean meal (SBM) and provided 8.7 g/kg stachyose and 3.1 g/kg raffinose. The duration of the study was 42 d. 3. Stachyose contents above 12.0 g/kg depressed group body weights, average daily gain and feed/gain but not feed intake during the whole experimental period. Broiler growth decreased linearly and quadratically with increasing stachyose content. No differences were detected between diets supplemented with 12.0 g/kg stachyose and SBM. 4. Nutrient digestibility tended to decrease but not significantly with increasing stachyose. 5. Stachyose content had no significant positive effects on caecal pH, microflora population and the resulting short-chain fatty acid (SCFA) metabolites during the 42 d experiment, with only butyrate differing significantly in the initial period.     

Immune responses in piglets infected with highly pathogenic porcine reproductive and respiratory syndrome virus

Porcine reproductive and respiratory syndrome virus (PRRSV) infection compromises the host's innate and adaptive immunity. The aim of this study was to investigate the immune responses of piglets infected with highly pathogenic (HP) PRRSV (HuN4 strain) with or without the immunization with CH-1R attenuated PRRSV vaccine. The response was evaluated for the clinical signs, pathological changes and virus load in immune organs, antibody responses and levels of serum IFN-γ, IL-4 and IL-10. The result showed that in comparison with the piglets received the immunization, the piglets infected with HP-PRRSV alone had the thymus atrophy, decreased serum levels of IL-4 and increased serum levels of IL-10 and INF-γ. These results suggest that elevated IL-10 levels at the early stage of the infection may enhance virus survival and delay the induction of protective immunity, while increased levels of IL-4 induce the effective immune responses and increase the animals' health status.     

高等农林院校数学建模教育研究与实践

结合1994～1998年甘肃农业大学大学生数学协会数学建模讨论班的实践经验,提出了：高等农林院校数学素质教育内容应包括数学基础教育、数学建模教育、数学建模实践3方面;数学建模教育的形式是“讨论班”;数学建模能力巩固、提高的方式是数学建模竞赛;要培养真正合格的素质型建设人才必须在大学期间参加适当的数学建模实践。并指出只有更多的专家、教授、学者参与到数学素质教育中来,使专业与数学教育真正相结合,数学建模教育乃至数学素质教育的口的才能真正实现。     

作物遥感估产的现状及其展望

 总结了国内外作物遥感估产的状况，并对作物遥感的技术集成和便利化服务、数据处理、农业标准化、农学机理、扩大用户需求共4个方面作了展望。     

柑桔黑斑病的发病特点及检测方法研究进展

柑桔黑斑病(Citrus Black Spot,CBS)是一种真菌性病害,主要为害果实,并产生褐色斑点,严重时蔓延至全果,造成果实腐烂,显著影响果实的品质和外观,降低经济价值,被欧美等国列为重要的检疫性病害,近年来该病在我国一些柑桔产区已上升为主要病害。本文主要从柑桔黑斑病的病原菌、发病特点及检测方法等几个方面进行简要的概述。     

板栗壳色素的提取研究进展

板栗壳色素是一种天然色素,具有一定的抗氧化和抑菌作用。综述了板栗壳色素的理化性质,重点介绍了板栗壳色素的提取方法,展望了板栗色素的应用前景。     

高效液相色谱(High-performance liquid chromaography)测定水产品中孔雀石绿及其代谢物的残留量的检测方法

本中心应用《水产品中孔雀石绿残留量的测定液相色谱法》（SC／T3021—2004）检测方法，多次对实际水产品中孔雀石绿及其代谢物的残留量进行检测，总结了一些经验并对方法中的一些环节进行了改进，使检测方法更加科学，回收率更合理，符合要求，检出限更低。     

东方百合L_sCCR1基因的克隆及表达分析

百合茎秆的挺度直接关系到百合花采收后的货架寿命等重要商品性状,而这些商品性状与植物茎秆中的木质素的含量高低有关.本文应用RLM-RACE技术,从东方百合索蚌植株中克隆了木质素合成相关基因一肉桂酰辅酶A还原酶,定名为LsCCR1.该基因cDNA全长为1 499 bp,包括完整的阅读框,编码388个氨基酸.多重比对分析发现百合LsCCR1基因与其他植物上已经发现的CCR基因同源性多介于55%～66%之间.利用半定量PCR检测LsCCR1基因在百合不同组织中的表达差异,结果显示LsCCR1基因主要在百合的茎秆中表达,根部次之,叶片、鳞茎及花蕾中表达量较少,其表达模式与拟南芥、桉树及大麦中CCR基因的表达模式类似.