美洲型猪繁殖与呼吸综合征病毒实时荧光RT-PCR定量检测试剂盒测量不确定度研究

为填补测量不确定度在兽医领域病原学检测的空白,建立猪繁殖与呼吸综合征病毒(PRRSV)实时荧光定量RT-PCR检测试剂盒测量不确定度评估模型,对市售的3种美洲型PRRSV实时荧光RT-PCR检测试剂盒进行了测量不确定度评估,评估了移液器、温度、重复性测量因素对试验结果产生的不确定度影响。研究数据表明:移液器与重复性测量对试验结果产生的不确定度影响较大,应予以重视,需规范操作;建立的3种试剂盒测量不确定度模型缩小了试剂盒对可疑样品的判定区域,对样品临界参考值的检测结果判定具有实际意义。通过比对4个厂家的核酸提取试剂,筛选出了提取效率最高的试剂盒。本研究建立的PRRSV实时荧光RT-PCR定量检测试剂盒测量不确定度模型为兽医实验室检测结果不确定度评估及应用奠定了基础。     

瘤胃微生物生态研究方法评述

瘤胃微生物生态研究方法主要经历了微生物纯培养、混合培养、微生物分子生物学技术[(从瘤胃中提取DNA,进行PCR-16S rDNA(rRNA)技术]、变性梯度凝胶电泳(DGGE)技术),在不同程度上揭示了瘤胃微生物群落丰富的多样性和生态功能.但由于各种方法本身的局限性,限制了人类对瘤胃微生物的全面了解,现代生物技术和传统微生物研究方法的配合将为瘤胃微生物生态研究提供较好的前景.     

Study on Decision Method in Choosing MIS Softwares for Manufacturing Enterprises

The decision objects and evaluation target architecture in choosing Management Information Systems (MIS) softwares for manufacturing enterprises are proposed. Fuzzy mathematics comprehensive evaluation method is used in decision analysis. The method in is applied practically.     

输水管道装置增压泵的节能分析

在输水管道均匀分流和沿管长水力坡降不变的情况下,对一级集中供水泵站、中间加设加压泵站及管道增压泵三种方案的能耗进行了分析。结果表明,采用管道增压泵节能效果最好,并确定了加压泵站及管道增压泵的最佳位置计算式。     

Effect of plant density in coupled aquaponics on the welfare status of African catfish,Clarias gariepinus

We investigated the effects of plant density on the welfare of African catfish, Clarias gariepinus, in coupled aquaponics over 85 days. The moderate density (mpd) of basil, Ocimum basilicum, was compared with the high density (hpd) and control (n = 0). The behavior was analyzed by visual and video observations, and after the application of induced stressors, skin injuries, blood glucose, lactate, and plasma cortisol responses were considered. The hpd fish showed the least activity (control: visual 77.8%, video 81.6%; mpd: 74.6%, 82.6%; hpd: 63.2% [p < 0.05], 78.8%). High agonistic behavior (control: 5, 131; mpd: 4, 57; hpd: 1, 45) and the highest number of injuries (control: 3.9; mpd: 2.9; hpd: 3.4) were observed in the control. Glucose and lactate levels did not differ significantly (control: 5.5, 2.6 mmol/L; mpd: 5.6, 2.7 mmol/L; hpd: 5.3, 2.6 mmol/L); however, cortisol levels did (control: 18.8 ng/mL, mpd: 19.9 ng/mL, hpd: 25.8 ng/mL). pH adjustment led to additional stress, resulting in temporal cortisol alterations. While in the control and mpd, low cortisol levels were followed by acute responses and downregulation, the hpd fish showed prior elevation and lagged an acute response. However, comparing injuries and behavioral patterns with control, aquaponics with high basil density influenced African catfish positively.     

3种淡水鱼肌肉脂质的组成及营养评价

以拉萨河拉萨裸裂尻鱼(Schizopygopsis younghusbandi)、拉萨裂腹鱼(Schizothorax waltoni)、双须叶须鱼Ptychobarbus dipogon)为材料,研究了其肌肉中脂质的组成和含量。结果显示:10种含量最丰富的脂肪酸分别是饱和脂肪酸16∶0和18∶0;单不饱和和脂肪酸16∶1n-9、18∶1n-9和18∶1n-7;n-3型多不饱和脂肪酸20∶5n-3,22∶5n-3和22∶6n-3和n-6型多不饱和脂肪酸18∶2n-6和20∶4n-6。结果表明拉萨河鱼类的脂肪酸模型跟深海鱼类相似,而且n-3型多不饱和脂肪酸的含量相对较高。     

柴油发动机富氧燃烧理论分析

对柴油发动机的燃烧过程进行分析,建立燃烧的热化学动力学模型。通过对燃料燃烧的放热效率及燃烧生成物进行分析,进而对柴油发动机富氧燃烧的可行性进行理论分析。     

西藏白菜型油菜油体特征与营养品质及油体提取物的SDS-PAGE分析

【目的】探索白菜型油菜种子油体、油体蛋白表型与含油量和蛋白质、脂肪酸含量之间的关系,分析油体提取物蛋白亚基的多态性,为西藏白菜型油菜高油新品种的选育奠定基础。【方法】测定36份来自西藏不同地区的白菜型油菜农家种、野生近缘种种子的含油量和蛋白质、脂肪酸含量;利用Leica DM5000生物显微镜观察所提取油体的大小及油体蛋白的表型特征;利用SDS-PAGE对供试材料油体提取物进行凝胶电泳,分析供试材料的遗传多态性和进化关系。【结果】36份供试材料芥酸、油酸、亚油酸和烯酸含量分别为27.39~132.33,3.22~143.22,31.22~53.62和14.27~111.48mg/g,其他脂肪酸含量相对较低;36份材料的含油量为57.20~151.37mg/g,蛋白质含量为38.68~73.87mg/g。相关分析显示,含油量与蛋白质含量、棕榈酸、烯酸含量呈极显著负相关。根据含油量将供试材料划分为高油组(含油量≥138mg/g,HO)、中油组(110mg/g≤含油量138mg/g,MO)、低油组(含油量110mg/g,LO)3个类别,不同含油组材料油体和油体蛋白形状均以近圆形为主,HO油体平均粒径2.12μm,油体蛋白平均粒径5.24μm;MO油体平均粒径1.82μm,油体蛋白平均粒径4.58μm;LO油体平均粒径1.44μm,油体蛋白平均粒径3.81μm。相关分析表明,油体平均粒径与含油量呈极显著正相关,与蛋白质含量呈极显著负相关,而与脂肪酸含量相关性不大。油体粗提液SDS-PAGE电泳共分离出迁移率不同的蛋白谱带32条,出现频率为5.6%~100%;蛋白谱带的分子质量为25.5~128.7ku,且分布较集中区域在87.8~27.4ku;蛋白谱带N-J聚类分析表明,供试材料遗传相似系数为0.610~0.980,在遗传相似系数0.835处可将36份材料聚为9个类群。【结论】西藏白菜型油菜遗传变异丰富,在西藏高油白菜型油菜品种选育时可将油体粒径大且数量多、油体蛋白少且粒径大作为筛选亲本的条件。     

腹泻犬源大肠埃希菌耐药性以及整合子–基因盒检测研究

【目的】了解腹泻犬源大肠埃希菌Escherichia coli的耐药性以及整合子携带情况。【方法】采用K-B纸片扩散法对30株分离自腹泻犬的大肠埃希菌进行19种抗菌药物的敏感性试验;PCR检测菌株中是否携带Ⅰ、Ⅱ、Ⅲ型整合酶基因,对携带有整合酶基因的阳性菌株进一步检测sul1、qac EΔ1基因以及可变区基因盒携带情况。【结果】30株分离株对19种抗菌药物表现出不同程度的耐药性,共产生18种耐药谱,对阿莫西林、氨苄西林、四环素和多西环素的耐药性较高,耐药率分别为90.00%、83.33%、66.67%和63.33%;对其余药物耐药性较低,耐药率低于14.00%;11株分离株含有Ⅰ型整合酶基因且均携带sul1和qacEΔ1基因,未检出Ⅱ型和Ⅲ型整合酶基因;Ⅰ型整合子阳性菌株中,有2株扩增出1 879 bp的耐药基因盒:dfrA12+orfF+aadA2。【结论】本次检测的腹泻犬源大肠埃希菌对抗菌药物呈不同水平的耐药性;基因盒介导的耐药性与菌株的耐药表型存在部分相关性,大肠埃希菌的耐药性与Ⅰ型整合子存在一定关系。     

Contrasted optimal environmental windows for both sardinella species in Senegalese waters

We investigate Sardinella aurita and Sardinella maderensis recruitment success relative to the variability of oceanographic conditions in Senegalese waters using generalized additive models (GAM). Results show that recruitment of both species is marked by a strong intra‐annual (seasonal) variation with minimum and maximum in winter and summer, respectively. Their interannual variations are synchronous until 2006 (recruitment decreasing), while from 2007 there is no synchrony. The model developed shows that sardinella recruitment variability is closely related to the tested environmental variables in the study area. However, the key environmental variables influencing the recruitment success are different for both species: the Coastal Upwelling Index and the sea surface temperature for S. aurita and S. maderensis, respectively. We report that recruitment success of S. aurita and S. maderensis are associated with distinct ranges of sea surface temperature, upwelling intensity, wind‐induced turbulence, concentration of chlorophyll‐a and north Atlantic oscillation index. Considering food security and socio‐economic importance of both stocks, we recommend that consideration is given to the environmental variability in the small pelagic fish national management plans, particularly in the context of climate change.