绿色富硒生物猪饲料中AFB1达标生产工艺优化研究

饲料中黄曲霉毒素(AFB₁)容易超标,检出率达80%~100%,毒性大,具强致癌性,可抑制生猪免疫机能,降低动物生产性能,引起动物继发感染,还会在动物产品中残留而威胁人类健康,给生猪养殖带来经济损失,降低猪肉食品安全性。本文通过使用先进固体发酵系统设备和益生菌发酵技术,采用单因素试验和响应面中试优化,获得发酵降解猪饲料AFB₁的最佳工艺参数为硒浓度0.3 mg/kg,发酵时间12 h,量子波强度30 Hz,益生菌菌种组合CGMCC NO.17328混合CGMCC NO.15611。该工艺将猪饲料AFB₁量从63.41μg/kg降解到2.98μg/kg,降解率达到95.30%,AFB₁含量达到国家饲料安全标准。生产工艺适合养猪场低成本快速生产AFB₁达标猪饲料。     

乳酸杆菌制剂对肉仔鸡肠道菌群、血清球蛋白及生产性能的影响

120只1日龄艾维茵肉仔鸡饲喂不同水平乳酸杆菌制剂,研究乳酸杆菌制剂对肉仔鸡的饲喂效果。结果表明,乳酸杆菌制剂在提高肉仔鸡成活率、增重和改善饲料利用率方面有一定的促进作用,但效果不显著(P>0.05)。而在改善肠道菌群结构和提高血清球蛋白方面效果显著(P<0.05)。     

微机综合自动化系统在大型泵站中的应用

水利部“94．8”项目之一“江都抽水机站机组监控关键技术”的实施，在国内首次实现了大型泵站“无人值守，少人值班”的新局面，该系统自动化调节功能，充分利用潮汐河流的特点，实现了泵站的优化调度，提高了运行效率，挖掘了泵站的潜在抽水能力，不仅节约了运行费用，而且还能增灌农田，显著地提高了经济效益和社会效益。     

吉林省西部新开发水田遥感动态监测研究

为了响应土地整理开发项目的政策,吉林省西部地区开发了大面积的水田。为掌握新开发水田的动态变化,有必要对吉林省地区进行土地利用分类。以吉林省前郭县为例,利用2010年环境卫星数据进行不同土地利用分类方法的比较,进而对另外3景图像进行信息提取,分析4个年份新开发水田的分布及变化情况。结果表明,支持向量机法比最大似然法的耕地分类精度高约5%,其产品和用户精度分别为95%和84%。加入纹理信息没有显著提高分类精度。2009~2012年水田面积分别增加-67.7 km2,111.7 km2和265.01 km2。     

不同光质LED光源对鱼腥草幼苗膜脂过氧化及抗氧化酶的影响

以鱼腥草为材料,以日光灯处理为对照,分析了不同光质LED光源(白、红、黄、绿、蓝LED灯)对鱼腥草叶片活性氧、类黄酮含量及抗氧化酶的影响。结果表明,蓝光下叶片中TBARS(硫代巴比妥酸)含量最高,较对照高30.18%,与希夫试剂染色结果相一致;过氧化氢产生最多,较对照高190.21%,与DAB染色结果一致;超氧阴离子产生速率在蓝光下最高,为对照组的1.54倍,白光下最低;蓝、绿光下脯氨酸含量是对照的2倍;蓝光和黄光处理下,黄酮含量较对照提高了21.4%。蓝、绿光提高了SOD2同工酶的表达,且在蓝光下最高;蓝、绿、红、黄光处理分别诱导了更多的POD基因位点的表达;不同LED光质均提高了CAT抗氧化酶活性,其中蓝、绿光下CAT同工酶的表达量明显高于对照。综上所述,蓝色光处理可以有效提高幼苗的抗氧化能力,可为鱼腥草品质的控制提供参考。     

Association analysis for detecting significant single nucleotide polymorphisms for phosphorus-deficiency tolerance at the seedling stage in soybean [Glycine max (L) Merr.]

Tolerance to low-phosphorus soil is a desirable trait in soybean cultivars. Previous quantitative trait locus (QTL) studies for phosphorus-deficiency tolerance were mainly derived from bi-parental segregating populations and few reports from natural population. The objective of this study was to detect QTLs that regulate phosphorus-deficiency tolerance in soybean using association mapping approach. Phosphorus-deficiency tolerance was evaluated according to five traits (plant shoot height, shoot dry weight, phosphorus concentration, phosphorus acquisition efficiency and use efficiency) comprising a conditional phenotype at the seedling stage. Association mapping of the conditional phenotype detected 19 SNPs including 13 SNPs that were significantly associated with the five traits across two years. A novel cluster of SNPs, including three SNPs that consistently showed significant effects over two years, that associated with more than one trait was detected on chromosome 3. All favorable alleles, which were determined based on the mean of conditional phenotypic values of each trait over the two years, could be pyramided into one cultivar through parental cross combination. The best three cross combinations were predicted with the aim of simultaneously improving phosphorus acquisition efficiency and use efficiency. These results will provide a thorough understanding of the genetic basis of phosphorus deficiency tolerance in soybean.     

Effect of dipeptide on intestinal peptide transporter 1 gene expression: An evaluation using primary cultured chicken intestinal epithelial cells

Peptide transporter 1 (PepT1) is a transporter responsible for absorbing dipeptide and tripeptide in enterocytes and is upregulated by dipeptide in mammals. It has not been certain whether intestinal PepT1 expression is responsive to dipeptides in chickens because of the lack of in vitro study using the cultured enterocytes. This study established a primary culture model of chicken intestinal epithelial cells (IECs) in two-dimensional monolayer culture using collagen gel by which the response of chicken PepT1 gene expression to dipeptide stimuli was evaluated. The cultured chicken IECs showed the epithelial-like morphology attached in a patch-manner and exhibited positive expression of cytokeratin and epithelial cadherin, specific marker proteins of epithelial cells. Moreover, the chicken IECs exhibited the gene expression of intestinal cell type-specific marker, villin1, mucin 2, and chromogranin A, suggesting that the cultured IECs were composed of enterocytes as well as goblet and enteroendocrine cells. PepT1 gene expression was significantly upregulated by synthetic dipeptide, glycyl-l-glutamine, in the cultured IECs. From the results, we herein suggested that dipeptide is a factor upregulating PepT1 gene expression in chicken IECs.     

香蕉茎秆纤维提取机刀片的分析和优化设计—基于SolidWorks

为减小香蕉茎秆纤维提取机刀片工作时的最大应力,增大其安全系数,利用SolidWorks软件对刀片进行三维建模,运用软件的Simulation插件分析刀片的应力、应变云图,并对刀片相关尺寸进行优化设计。优化结果显示,刀片的最大应力由68.58MPa下降到49.33MPa,下降约28%;刀片的最小安全系数由3.21上升到4.47,增加了约1.4倍;刀片的质量由0.702kg下降到0.698kg,达到了优化的目标。     

去花对菊芋数量学性状的影响

以白皮菊芋为试材,通过对现蕾期菊芋去除1/4花、1/3花、1/2花、全部去除和不去花等5个处理,测定叶片、小花、分枝和块茎数量等相关指标,探讨了去花对菊芋数量学性状的影响规律,为提高菊芋块茎生物产量提供理论依据。结果表明:去花1/3、1/2和全株去花提高了单株菊芋块茎数量,降低单株块茎质量,1/4去花对菊芋单株块茎数量和单个块茎质量影响不显著;去花处理降低了二级分枝和一级分枝的数量;去花处理增加了单株叶片的数量和单片叶片的质量;随着去花数量的增加,单株小花数量呈现"降-升-降"的变化规律,单个小花质量呈现"降-升"的变化趋势。     

基于模糊层次分析法的农产品加工企业风险评价研究

风险评价是风险管理的重要阶段,针对农产品加工企业特点,提出了一种基于模糊层次分析法的农产品加工企业风险评价方法。该方法初步解决了农产品加工企业风险管理中的关键问题——风险因素的识别。以某农产品加工公司为例,介绍了该方法的应用过程。