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1.
依据GenBank公布的猪嗜淋巴疱疹病毒3型(porcine lymphotropic herpesviruses 3,PLHV-3)DNA序列,设计特异性引物,优化反应条件,建立荧光定量PCR方法,并对方法的灵敏度、特异性和重复性进行试验。得出方法的线性范围为:8.2×101~8.2×107,灵敏度可达82个拷贝,方法的特异性高,只能检测pMD18-T/PLHV3重组质粒,另外5种对照病原均未检出;方法的重复性好,对不同浓度的pMD18-T/PLHV3重组质粒分别扩增6次,结果重复性好。使用建立的方法检测100份临床样品,同时与普通PCR方法比较,显示荧光定量PCR检出率比普通PCR高,具有较高的灵敏度和准确性。结果表明:建立的荧光定量PCR可用于PLHV-3的临床快速诊断。 相似文献
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《中国家禽》2019,(17)
以具有种属特异性的鸭瘟病毒gC基因为靶基因,设计引物和荧光标记探针,使用重组酶介导扩增方法(Recombinase aid amplification assay,RAA),39℃恒温扩增,建立了检测鸭瘟病毒的普通和荧光RAA方法。该方法具有良好特异性,仅对鸭瘟病毒检测结果为阳性,而与番鸭细小病毒、小鹅瘟病毒、禽传染性喉气管炎病毒、马立克氏病毒、鸭源沙门菌、鸭源大肠杆菌O157无交叉反应。普通和荧光RAA方法的灵敏度分别为100 copies/μL和10 copies/μL,对28份留存的鸭瘟阳性组织样本和84份疑似鸭瘟临床样品检测结果表明建立的方法与商业化PCR试剂盒的符合率为100%。结果表明,RAA方法实现常温扩增、操作简单、费用低廉、无需热循环过程,是一项具有广泛前景的方法。 相似文献
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《养殖与饲料．饲料世界》2018,(11)
为了早期快速诊断近些年流行于国内的虾肝肠胞虫,根据GenBank中公布的虾肝肠胞虫EHP-SSU rDNA序列比对分析,在SSU基因内确定了一段156 bp的特异性较强的片段作为靶序列,设计并合成引物和探针,经过优化重组酶介导的核酸技术(Recombinase-aid-amplification,RAA)反应条件,建立快速检测虾肝肠胞虫的RAA恒温荧光检测方法。在RAA进行到24个循环反应时可以检测到的质粒最小浓度是10 copies/μL,相当于10个病毒粒子。利用该方法,从天然感染EHP的虾肝胰腺组织DNA中可以检测出片段,而健康的虾和感染了传染性皮下及造血组织坏死病毒(IHHNV)、对虾白斑综合症病毒(WSSV)和虾虹彩病毒(SIV)的组织则没有扩增条带。试验表明,本研究建立的RAA恒温荧光检测方法具有快速、成本低、特异性好、准确性高的特点,为大范围早期病害的快速检测提供了新方法。 相似文献
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《中国预防兽医学报》2020,(3)
为建立一种简便、快捷的现地检测鲤浮肿病毒(CEV)的方法,本研究联合重组酶介导扩增(RAA)和侧向流试纸条(LFD)技术,在优选的RAA下游引物和探针的5'端分别进行Biotin和FAM标记,通过RAA反应时间和温度等条件的优化,建立了可用于CEV现地检测的RAA-LFD方法。该检测方法在34℃～40℃恒温反应10 min即可实现对CEV目的基因片段的有效扩增;与其它常见水生动物疫病病原DNA无交叉反应;RAA扩增产物可以直接对LFD经肉眼观察结果,该方法对标准质粒pEASY-CEVP4a的最低检测限为6拷贝/μL,与荧光定量PCR灵敏度相当;组内和组间重复性试验表明该方法具有良好的重复性和稳定性;采用该方法和荧光定量PCR对60份临床样本同时进行检测,二者的阳性符合率为96.08%。本研究建立的RAA-LFD检测方法特异性强、灵敏度高、重复性好、操作方便,可用于CEV的临床快速检测。 相似文献
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采用PCR方法扩增PPV6保守区域基因252bp,将其克隆到pClon007载体,构建重组质粒作为标准阳性质粒。以质粒模板建立PPV6的SYBR GreenⅠreal-time PCR检测方法,并进行敏感性、特异性和重复性等验证。结果表明,重组质粒特异性好;建立的real-time PCR方法Ct值与标准品模板在8.80×109~8.80×101 copies/μL范围内呈良好的线性关系,相关系数为0.993,斜率为-4.320。该方法检测灵敏度可达8.80×101 copies/μL。该方法对JEV、PRV、PRRSV、PCV2、FMDV等猪常见病原检测均无特异性扩增;对临床样品的检测结果表明,所建立的荧光定量PCR阳性检测率为40.63%。本试验成功建立了PPV6SYBR Green I real-time PCR检测方法,可实现对PPV6快速灵敏的诊断。 相似文献
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为建立一种鉴别诊断野生株和基因缺失株非洲猪瘟病毒(African swine fever virus, ASFV)的方法,针对ASFV的B646L、EP402R、DP96R基因保守序列设计3套引物和探针,优化三重荧光定量PCR体系作为基础建立微滴式数字PCR(droplet digital PCR,dd PCR)检测方法,并对方法的特异性、灵敏性及重复性进行评估。结果显示,优化后的多重荧光定量PCR检测方法的标准曲线线性关系良好,对PRRSV、PEDV、PRV、VSV、PCV、RNase-free水、重组质粒标准品进行特异性检测,特异性良好;重复性试验结果显示,变异系数均小于2%;对3种重组质粒的最低检测下限均为102 copies/μL。参照上述多重荧光定量PCR方法优化后的条件,进行多重ddPCR检测方法的建立,并且对该方法进行评价。结果显示,ddPCR检测方法标准曲线的线性关系良好;特异性及重复性良好;最低检测下限B646L为11.6 copies/μL、EP402R为13.3 copies/μL、DP96R为16.9 copies/μL;ddPCR的检测灵... 相似文献
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为建立一种快速、特异的Ⅰ型鸭肝炎病毒（DHV-Ⅰ）SYBR GreenⅠ荧光定量PCR检测方法,根据GenBank已登录的DHV-Ⅰ型疫苗株C80（DQ864514.3）的非编码区基因序列设计1对特异性引物,经RT-PCR扩增出230bp的靶序列,并克隆到pMD18-T载体上,构建重组质粒;将纯化的重组质粒10倍梯度稀释后作为标准阳性模板,进行SYBR GreenⅠ荧光定量PCR扩增并建立标准曲线,对其敏感性、特异性和重复性进行评价。结果显示,建立的标准曲线的循环阈值与模板浓度呈现良好的线性关系（R2=0.998 2）,产物Tm值为87.2～87.9℃,检测灵敏度为71.5拷贝/μL。对55份疑似病料进行检测,荧光定量检测48份为阳性,而用常规PCR方法只能检出39份阳性,ELISA方法只检出30份阳性。这表明所建立的DHV-Ⅰ的SYBR GreenⅠ荧光定量PCR检测方法具有特异、灵敏、快速和重复性良好等优点,可用于临床DHV-Ⅰ感染的快速检测,为DHV的分子诊断、流行病学调查及定量分析奠定了基础。 相似文献
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为了对牛呼吸道合胞体病毒(bovine respiratory syncytial virus, BRSV)进行准确定量检测，针对BRSV F基因设计特异性引物，构建pMD19T-BRSV-gF重组质粒，以其为模板优化反应条件及反应体系，建立TB GreenⅡ荧光定量PCR方法并应用于临床BRSV检测。结果显示，针对BRSV F基因建立的TB GreenⅡ荧光定量PCR方法标准曲线线性关系良好，相关系数为0.995 2;灵敏度高，BRSV最低检测限达3.9×101 copies/μL;特异性良好，可特异性检测出BRSV,对牛传染性鼻气管炎病毒和牛病毒性腹泻病毒的扩增呈阴性；重复性好，批内和批间重复性试验变异系数均小于2%。对50份临床样品进行检测，荧光定量PCR对BRSV的阳性检出率(26%)明显优于常规PCR方法(14%)。结果表明针对BRSV F基因建立的TB GreenⅡ荧光定量PCR检测方法适合BRSV的临床检测。 相似文献
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《中国动物传染病学报》2019,(6)
为建立良好的犬腺病毒检测方法,参考GenBank中犬腺病毒毒株(GenBank登录号:U77082.1)的E3基因,设计并合成了一对特异性引物。扩增的目的片段与pMD19-T载体相连接构建重组质粒,以该重组质粒为模板建立特异性好、灵敏度高且可快速检测犬腺病毒的SYBR GreenⅠ荧光定量PCR检测方法。经特异性方法验证,在常见的五种犬病毒病中,本方法只能检测出犬腺病毒存在。敏感性试验结果表明,本方法的灵敏性较普通PCR方法高出100倍。重复性试验结果的变异系数均不高于0.95%。本方法的建立可为犬腺病毒的检测提供技术支持。 相似文献
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依赖于核酸序列恒温扩增技术快速检测副溶血性弧菌方法的建立 总被引：2，自引：0，他引：2
为建立副溶血性弧菌的快速检测方法,本研究采用依赖于核酸序列恒温扩增(NASBA)技术,以副溶血性弧菌的tlh基因为扩增的靶基因设计特异性引物和探针,建立可快速扩增副溶血性弧菌的NASBA方法.特异性和灵敏度试验结果表明:该NASBA方法对副溶血性弧菌的最小检出量为5.1×102 cfu/mL,高于普通PCR方法,而且与其他种属的菌无任何交叉反应.此外,本研究将副溶血弧菌扩增产物采用通用型核酸扩增物快速检测板进行检测,实现了特异性强的快速副溶血弧菌的检测.该方法对仪器要求低,具有良好的应用前景. 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献