Establishment and Application of Loop-mediated Isothermal Amplification for Rapid Detection of Porcine Epidemic Diarrhea Virus     

LUO Ya-kun  LIANG Lin  WANG Jing  LIU Cun  LIU Qi  LIU Chang  LIN Wen-cheng  CUI Shang-jin 《中国畜牧兽医》2017,44(2):344-349

This study was aimed to establish a loop-mediated isothermal amplification (LAMP) assay for detection of porcine epidemic diarrhea virus (PEDV), and provide a simple, sensitive, accurate and reliable tool for diagnosis of PEDV.The conservative PEDV N gene (GenBank accession number: KT799997) of PEDV was selected as a target to design six specific primers.The reaction system and temperature of LAMP were optimized, and the LAMP method for specific amplification of PEDV was established. Results showed that the PEDV LAMP detection method was established successfully, and it could detect PEDV specifically at 60℃ for 60 min,and the detection limit was 91 copies/μL, which was one hundred-fold higher than conventional RT-PCR method.75 clinical samples were detected by LAMP and PCR, respectively, the coincidence of LAMP and PCR was about 97.3%. All the data suggested that the LAMP assay had strong specificity, high sensitivity, simple operation, low equipment requirement, and was suitable for rapid detection of PEDV clinical samples.  相似文献   

应用CNCPS方法和体外产气法研究豆腐渣饲料的营养价值     

李岩  孟庆翔  陈万宝  刘畅  周振明 《中国畜牧兽医》2017,44(5):1355-1362

为揭示豆腐渣对反刍动物的饲用价值,本试验采用康奈尔净碳水化合物-蛋白质体系（CNCPS）和体外产气法对豆腐渣营养价值进行评定。测定豆腐渣的CNCPS营养成分与体外发酵参数,应用CNCPS公式计算碳水化合物（CHO）和粗蛋白质（CP）中各组分含量。结果显示,豆腐渣的CP含量为14%~25%,粗脂肪（EE）含量为1.9%~2.9%,代谢能（ME）为10~12 MJ/kg DM;易在瘤胃中降解的蛋白质（PA＋PB₁）和在瘤胃中缓慢降解的粗蛋白质（PB₂＋PB₃）的含量相当,不可降解真蛋白质（PC）含量较少;潜在可利用碳水化合物（CA＋CB₁＋CB₂）较高;体外发酵产气量均达到70 mL,氨态氮（NH₃-N）浓度在8~23 mg/dL,总挥发性脂肪酸（TVFA）在46~70 mmol/L。而不同来源的豆腐渣营养成分和发酵情况存在显著差异,且CNCPS碳水化合物、蛋白质组分的优劣不同。凌源豆腐渣的最大产气量（B）最高,极显著高于其他3种苹果渣（P＜0.01）,而各豆腐渣的产气速度（C）无显著差异（P＞0.05）。辽源豆腐渣氨态氮（NH₃-N）含量最高,极显著高于其他饲料（P＜0.01）。不同地方豆腐渣瘤胃液挥发性脂肪酸比例差异极显著（P＜0.01）。不同来源的豆腐渣的总可消化养分（TDN）及其他能值差异较大,以新民豆腐渣的能值最低,极显著低于其他苹果渣（P＜0.01）。综上可知,作为反刍动物非粮饲料,豆腐渣为反刍动物提供的可利用能值高,利于瘤胃微生物蛋白质合成。  相似文献   

The Epidemiology and Characteristics of Q fever and Co‐infections with Scrub Typhus,Murine Typhus or Leptospirosis in Taiwan: A Nationwide Database Study          下载免费PDF全文

C.‐H. Lai  W. Sun  C.‐H. Lee  J.‐N. Lin  M.‐H. Liao  S.‐S. Liu  T.‐Y. Chang  K.‐F. Tsai  Y.‐C. Chang  H.‐H. Lin  Y.‐H. Chen 《Zoonoses and public health》2017,64(7):517-526

Q fever (QF) is a worldwide zoonosis associated with outbreaks. Only a few nationwide studies regarding the surveillance and epidemiology of human QF have been reported. Although QF is endemic in Taiwan, a nationwide database investigation of the epidemiology and characteristics of QF and its associations with scrub typhus (ST), murine typhus (MT) and leptospirosis (LS) has never been reported. We analysed nationwide databases of suspected QF, ST, MT and LS cases from October 2007 to December 2014 obtained from the Centers for Disease Control, Taiwan. A total of 468 (4.2%) QF cases were identified among 11 109 suspected QF cases. QF cases were mainly distributed in the southern and Kaohsiung–Pingtung regions but rarely in the eastern region. Compared to non‐QF cases, QF cases had significantly higher percentages of males (88.7 versus 66.2%) and high‐risk occupations (farming, animal husbandry or veterinary medicine) (16.2 versus 10.5%). But the percentages of specific animal contact, including cattle (0.6 versus 0.8%) and goats (0.9 versus 1.0%), were low in both. The majority of suspected QF cases (89.4%) were simultaneously suspected with ST, MT or LS, and the combinations of suspected diseases differed between regions. The number of suspected QF cases from the eastern region decreased since 2009, which was not observed in other regions. A total of 1420 (12.8%) cases had confirmed diseases, including QF (453, 4.1%), QF+ST (7, 0.06%), QF+MT (4, 0.04%), QF+LS (4, 0.04%), MT (186, 1.7%), ST (545, 4.9%), ST+LS (11, 0.1%) and LS (210, 1.9%). Compared to cases of unknown disease, QF cases had larger percentages of high‐risk occupations (16.2 versus 9.6%) but similar histories of animal contact (29.8 versus 25.1%). QF is an endemic disease in southern Taiwan. It is difficult to differentiate QF from ST, MT or LS only by high‐risk occupations and history of animal contact, and co‐infection of QF with these diseases should be considered.  相似文献   

我国青藏高原地区牦牛草地放牧系统管理及优化   总被引：2，自引：1，他引：1  

罗惦  柴林荣  常生华  程云湘  侯扶江 《草业科学》2017,34(4)

基于牦牛所处地理环境,即青藏高原的特殊性,以及牦牛放牧这一生产方式在该地区第一产业中的重要地位,国内外学者从牦牛放牧系统的管理出发,对该系统中各因子之间的相互响应进行了研究,主要包括当放牧制度不同时,系统中的初级生产力和次级生产力的表现特征。从不同放牧制度中草地和家畜的特征表现,再到人为管理对这两种生产力的影响,研究者通过对比和试验进行了系统优化方法的探索。笔者通过对现阶段已有的研究成果进行整理和分析,概括在不同的放牧管理方式下草地放牧系统中的牦牛在生产力水平方面的差异,以及草地对不同放牧强度的响应,探究青藏高原地区牦牛放牧方式如何影响草畜之间的互作关系。在此基础上,分析其在实际生产活动中存在的问题,以及如何通过改进管理制度优化生产的办法,并对牦牛放牧系统发展进行了展望。  相似文献   

污泥对草坪草逆境生理的影响     

尚明娟  曹骏  常智慧 《草业科学》2017,34(8)

日益增长的污水处理副产物——污泥的处置问题越来越引起人们的关注,将污泥应用于草坪草的种植被认为是污泥资源化利用的可行途径之一。本文综述了污泥对草坪草逆境生理影响的研究进展,众多研究表明,适宜用量的污泥对草坪草叶绿素及光合效应、矿质营养、渗透调节物质和抗氧化酶系统均有有益影响,能提高其应对逆境的适应能力;过量施用污泥则会影响草坪草的生长,不同的草种对污泥施用量的要求不同。污泥能提高草坪草抗逆性的原因可能是由于污泥富含多种营养元素和生物活性物质,但其提高草坪草抗逆性的内在机制还有待进一步研究。  相似文献   

The transcription factor OsbHLH035 mediates seed germination and enables seedling recovery from salt stress through ABA-dependent and ABA-independent pathways,respectively     

Hung-Chi Chen  Wan-Hsing Cheng  Chwan-Yang Hong  Yu-Sen Chang  Men-Chi Chang 《Rice》2018,11(1):50

  相似文献   

基于PSR-CPM模型的市域土地生态安全评价   总被引：4，自引：0，他引：4  

郭宇伦  师学义  璩路路  刘畅 《水土保持研究》2017,24(4):108-112

以PSR模型为基础,构建目标层、准则、因素层和指标层4级评价体系,运用突变级数法（CPM）对2005—2014年晋城市土地生态安全水平进行了评价。结果表明:2005—2008年,晋城市土地生态安全水平呈上升趋势,达到临界安全状态;2008—2009年,土地生态安全呈下降趋势,降低到较不安全水平;2009—2013年,土地生态安全水平呈上升趋势,并稳定在较安全水平;2013—2014年土地生态安全水平略有下降趋势,再次降低到较不安全状态。2005—2008年的变化主要是晋城市开展造林工程和产业结构改革的结果;2008—2009年的变化主要是受经济危机和旱灾的影响;2009—2013年的变化主要是由于经济、粮食产量的恢复和工业污染得到有效控制;2013—2014年的变化主要是经济发展减缓和人口增长所造成的。针对主要限制因素,晋城市今后应更加注重产业结构转型,控制工业污染排放和增加农业灌溉设施这三个方面的工作。  相似文献   

基于能值的资源型城市新陈代谢过程对比分析     

璩路路  师学义  刘畅 《水土保持研究》2017,24(1):279-284

城市新陈代谢注重分析城市物质、能量和货币的流动过程,这为探讨不同职能城市的城市代谢过程提供了新的视角。为了探讨不同资源型城市的新陈代谢特点和变化规律,分别以山西省省会资源型城市太原市和传统资源型城市晋城市为例,基于太原市和晋城市2007—2014年的社会经济数据,运用能值理论构建了8项反映城市新陈代谢的评价指标体系,从城市新陈代谢系统能值结构、能值使用强度、能值环境压力和新陈代谢产出效率4个方面,对太原市和晋城市2007—2014年城市新陈代谢状况进行了对比分析。结果表明:2007—2014年,总体上,太原市的城市新陈代谢系统能值结构优于晋城市,晋城市的能值使用强度高于太原市,晋城市的能值环境压力大于太原市,太原市的新陈代谢产出效率高于晋城市。通过对比分析后对提高太原市和晋城市的城市新陈代谢过程提出了建议,为创造性地解决山西省新陈代谢资源与生态风险问题奠定基础,进而为城市生态管理提供科学依据。  相似文献   

非常规水水质对红壤水分运移参数的影响及其过程模拟   总被引：2，自引：1，他引：1  

刘常  王辉  胡传旺  朱晋斌  万琳辉  胡晨雨 《水土保持学报》2017,31(5):170-175

为了探究非常规水水质对亚热带红壤水分运移参数的影响,采用蒸馏水(CK)、再生水(RW)、稀释2,4,6倍再生水(RW-D2、RW-D4、RW-D6)和生活污水(_(WW))等6种不同水质的非常规水模拟红壤水分入渗过程,利用水平土柱吸渗法测定红壤湿润锋运移速率和水分扩散度,应用压力膜仪法测定了土壤水分特征曲线并且借助van Genuchten(VG)模型提取了相应的土壤残余含水量θ_r、土壤饱和含水量θs、α和n等特征参数值。结果表明:不同水质入渗下红壤湿润锋运移速率、水分扩散度均存在着一定差异,湿润锋运移速率由快到慢分别为V_(CK)≈V_(RW-D2)V_(RW-D6)≈V_(RW-D4)V_(WW)V_(RW);在同一含水率下D_(RW-D6)(θ)D_(RW-D4)(θ)D_(WW)(θ)D_(RW-D2)(θ)D_(CK)(θ)D_(RW)(θ)。不同水质处理对VG模型参数变化率的影响程度不同,对α的影响最大,对θ_r的影响最小。因此,非常规水灌溉会降低红壤入渗速率、持水性能以及抗旱能力。  相似文献   

Analysis of Multiple Binary Responses Using a Threshold Model     

Ling-Yun Chang  Sajjad Toghiani  Ashley Ling  El H. Hay  Sammy E. Aggrey  Romdhane Rekaya 《Journal of Agricultural, Biological & Environmental Statistics》2017,22(4):640-651

Several discrete responses, such as health status, reproduction performance and meat quality, are routinely collected for several livestock species. These traits are often of binary or discrete nature. Genetic evaluation for these traits is frequently conducted using a single-trait threshold model, or they are considered continuous responses either in univariate or in multivariate context. Implementation of threshold models in the presence of several binary responses or a mixture of binary and continuous responses is far from simple. The complexity of such implementation is primarily due to the incomplete randomness of the residual (co)variance matrix. In the current study, a multiple binary trait simulation was carried out in order to implement and validate a new procedure for dealing with the consequences of the restrictions imposed to the residual variance using threshold models. Using three and eight binary responses, the proposed method was able to estimate all unknown parameters without any noticeable bias. In fact, for simulated residual correlations ranging from ?0.8 to 0.8, the resulting HPD 95% intervals included the true values in all cases. The proposed procedure involved limited additional computational cost and is straightforward to implement independent of the number of binary responses involved in the analysis. Monitoring of the convergence of the procedure must be conducted at the identifiable scale, and special care must be placed on the selection of the prior of the non-identifiable model. The latter could have serious consequences on the final results due to potential truncation of the parameter space.  相似文献