云南东方蜜蜂形态特征与环境因子相关性的研究

云南东方蜜蜂种群内遗传变异丰富 ,每个形态性状特征均具有丰富的多态性 ,种群间具多型性 ,且种群中许多形态性状特征表现出较明显的地理变异性[1～ 3 ] 。从滇南 -滇中 -滇西北 ,随纬度或海拔的增加 ,形态特征变异的总趋势是 :蜜蜂个体增大、体色变深。具体是 :1.前翅长、宽 ,背板 3、 4宽 ;2 .后腿长 ,蜡镜长、宽 ,蜡镜间距 ,腹片 3、 6的长和宽逐渐增加 ;3.背板 3、 4的色素度 ,小盾片的色素度逐渐加深。云南东方蜜蜂种群形态性状的多态性、多型性及其生态地理变异式样 ,均具有生态适应意义 :与云南东方蜜蜂分布区的气候特点相适应 ,而且还与海拔高度和纬度的变化有着密切的适应关系     

蜂胶抗炎功效成分研究

为确定中国杨属型蜂胶的抗炎功效成分,用100ng/ml脂多糖(LPS)和40μg/ml氧化型低密度脂蛋白(ox-LDL)分别诱导脐静脉血管内皮细胞(HUVECs)损伤。通过SRB法分别检测蜂胶水提物中分离的11种组分和蜂胶乙酸乙酯提取物中分离的8段组分对2种炎症细胞模型细胞存活率的影响。结果表明:蜂胶水提物中的11种组分不同程度的促进2种炎症细胞的细胞存活率,乙酸乙酯提取物中的8段组分也是不同程度的提高2种炎症细胞的细胞存活率。由此可知,蜂胶的抗炎功效成分十分复杂,很可能是多种成分协同功效的结果,而且酚酸类物质发挥了一定的作用。     

Babesia gibsoni rhoptry-associated protein 1 and its potential use as a diagnostic antigen

A cDNA encoding the rhoptry-associated protein 1 (RAP-1) homologue was obtained by immunoscreening an expression library prepared from Babesia gibsoni merozoite mRNA. The complete nucleotide sequence of the gene was 1740bp. Computer analysis suggested that the sequence contains an open reading frame of 1425bp encoding an expected protein with a molecular weight of 52kDa. Based on the sequence similarity, this putative protein was designated as the B. gibsoni RAP-1 (BgRAP-1). The BgRAP-1 gene was expressed in the Escherichia coli BL21 strain, and the recombinant BgRAP-1 was used as the antigen in the enzyme-linked immunosorbent assay (ELISA). The results can differentiate between the B. gibsoni-infected dog sera and the Babesia canis infected dog sera or the normal dog sera. Furthermore, the antibody response against the recombinant protein was maintained during the chronic stage of infection, indicating that the recombinant BgRAP-1 protein might be a useful diagnostic antigen for the detection of antibodies to B. gibsoni infection in dogs.     

心水病病原体高度保守基因合成与原核表达

通过软件DNAStar分析,设计合成心水病病原体抗原性、保守性比较高的一段基因,长度为564bp,将它插入pUC57载体,再转入pET-32a质粒中进行原核表达并纯化表达产物。结果表明,合成的基因在大肠杆菌中得到高效表达并能简易地提纯,纯化的表达产物有望用于心水病免疫学检测;此合成外来基因还可以作为心水病病原PCR检测的阳性对照。这些工作为我国建立心水病防控技术储备奠定了一些基础,也为防控高度危险性外来传染病提供一种安全和可行的研究新思路。     

Locomotion Score and Its Impacts on Production Performance and Blood Routine Indexes in Chinese Holstein

To investigate the influencing factors of locomotion score (LS) and its impacts on production performance and blood routine index in Holstein,body condition score (BCS),LS and DHI (dairy herd improvement) of 1 486 lactating cows from two dairy farms,and the blood routine indexes of 101 lactating cows from one farm in Beijing were measured.The fixed model was used to analyze the impacts of herd,parity and lactation stage on LS,and the impacts of LS and BCS on daily milk yield,somatic cell score,milk composition and blood routine indexes in dairy cows.The results showed that both parity and lactation stage had significant impacts on LS.The LS increased with the increase of parit,the LS increased by 0.71 from first lactation to fifth and above lactation.The LS of cow in lactation stage Ⅲ(100-199 d) and Ⅵ (after 350 d) were significantly higher than cow in stage Ⅱ (45-99 d)(P<0.05),and both were higher than 2.The LS had no significant impacts on daily milk yield,milk composition and somatic cell score (P>0.05).However,the milk yield of the cow with LS≥4 was the lowest,and a decrease of 2.29 kg was found compared with the cow with LS=1.Among the various blood routine indexes,LS had significant impacts on red blood cell count,hemoglobin content,mean corpuscular hemoglobin concentration and lymphocyte count (P<0.05),and had no significant impacts on white blood cell count (P>0.05).With the increase of LS,the red blood cell count,hemoglobin content,mean corpuscular hemoglobin concentration and lymphocyte count of cows decreased with different extents.There were some problems on the body immunity and hematopoiesis of cows with poor LS.In dairy farm,regular evaluation of LS could be used to find the management problems of feet and legs,which had a great significance to reduce the loss of production performance and early culling caused by hoof disease.     

黄芪多糖对罗非鱼肠绒毛形态结构及肠道免疫细胞的影响

本试验旨在探讨黄芪多糖对罗非鱼肠绒毛形态及肠道黏液细胞和上皮内淋巴细胞的分布和数量的影响.选用平均体重为47 g的岁非鱼共150尾,随机分为5组,每组3个重复,每个重复10尾鱼.对照组饲喂基础日粮,试验组分别饲喂在基础日粮中添加500、1 000、1 500、2 000 mg/kg黄芪多糖的试验日粮.试验40 d后,从各组中随机抽取5尾罗非鱼进行解剖,取山肠管,固定、包埋并做成切片,并应用组织化学染色方法对各组肠管切片进行染色,观察肠绒毛形态结构、黏液细胞及上皮内淋巴细胞的分布和数量.结果表明:各组肠绒毛的结构郁较为完整;各试验组肠绒毛长度、隐窝深度和肌层厚度以及肠道黏液细胞和上皮内淋巴细胞的数量与对照组相比均有所提高,其中除前肠肌层厚度和前肠上皮内淋巴细胞数量外,1 000和1 500mg/kg组均较对照组有显著或极显著升高(P<0.05或P<0.01).由此得出,日粮中添加黄芪多糖可提高罗非鱼肠绒毛长度、隐窝深度和肌层厚度,增加肠道黏液细胞和上皮内淋巴细胞的数最,且以1 000和1 500 mg/kg两个添加量效果较好.     

柴油机掺烧桐油制备生物柴油的动力性和经济性

在ZX195型直喷式柴油机上进行了桐油制备的生物柴油和石化柴油不同配比的混合燃料试验研究.试验结果表明:在不对柴油机做任何调整的情况下,燃用B10和B20的桐油生物柴油对发动机动力性和经济性影响不大;燃用B50和B100的生物柴油时,动力性和经济性下降明显,其功率下降11%,油耗增加35%左右;综合考虑发动机的动力性和经济性,燃用B20较为合适.     

插秧机转向自动控制的研究与试验

以XDNZ630型水稻高速插秧机为平台,对插秧机的转向自动控制系统进行研究.对插秧机转向机构进行了改造,采用伺服电机驱动转向轴,带动转向轮偏转.采用GPS精确定位,PID控制转向执行机构,角度传感器反馈插秧机转向角的闭环控制系统实现了转向自动控制.试验结果表明,混凝土路上平均跟踪误差为6cm,最大跟踪误差11cm;在水田中平均跟踪误差为10cm,最大跟踪误差为20cm.     

基于随机森林回归的玉米单产估测

为了提高玉米单产估测精度,以河北省中部平原为研究区域,以条件植被温度指数(VTCI)和上包络线S-G滤波的叶面积指数(LAI)为特征变量,通过随机森林回归确定玉米主要生育时期VTCI和LAI的权重,构建加权VTCI和LAI与玉米单产的单变量和双变量估产模型。结果表明,基于随机森林回归的双变量估产模型精度最高(R~2=0. 303),达极显著水平(P 0. 001)。将随机森林回归双变量估产模型用于研究区域2012年各县(区)玉米单产估测,结果表明,53个县(区)玉米估测单产与实际单产的平均相对误差为9. 85%,均方根误差为824. 77 kg/hm~2,模型精度较高。基于随机森林回归双变量估产模型逐像素估测研究区域2010—2018年玉米单产,结果表明,玉米单产在空间上的分布特征为西部地区最高、北部和南部次之、东部地区最低,年际间的分布特征为在波动中呈先减少后增加的趋势。     

插秧机锥齿轮外壳的强度分析与优化

利用ANSYS软件对插秧机锥齿轮外壳结构建立了参数化几何模型和有限元分析模型,采用接触副合理解决了轴承和转轴间的接触问题。在此基础上进行了路面行驶危险工况和水田调头工况两种危险工况下的约束、加载和结构有限元分析计算,得到各工况下结构的应力分布和最大应力。采用ANSYS对插秧机锥齿轮外壳进行了优化设计,在满足结构外形变化不大的前提下,使结构强度得到提高。