猪伪狂犬病毒野毒株套式PCR检测方法

为建立能鉴别猪伪狂犬病病毒（PRV）野毒株和疫苗株的实用方法,本文以疫苗株缺失的3.5kb片段为靶基因,设计了2对PCR引物,建立了能够特异性检测PRV野毒株的套式PCR方法。与常规PCR相比,该方法检测极限可达10个病毒拷贝/μL,是常规PCR的1000倍,并与猪瘟病毒、猪蓝耳病病毒、猪细小病毒和猪圆环病毒等不存在交叉反应现象。在对临床150份样品检测时,套式PCR的阳性率为21.33%,常规PCR的阳性率为10%。这表明该方法具有特异性高、敏感性强的特点,是一种值得基层推广应用的快速诊断技术,可用于PRV的诊断和流行病学调查等。     

鸭副黏病毒和鸭圆环病毒二重荧光定量PCR检测方法的建立

根据鸭副黏病毒(DPMV)和鸭圆环病毒(DuCV)保守基因序列,设计了2对针对鸭副黏病毒和鸭圆环病毒的特异性引物和2条不同荧光基团标记的TaqMan探针,建立了鸭副黏病毒和鸭圆环病毒的二重荧光定量PCR检测方法。该方法敏感性好,对鸭副黏病毒和鸭圆环病毒的检测敏感性分别达到160和140个拷贝数;该方法特异性强,对鸭肝炎病毒、番鸭细小病毒、鸭瘟病毒和H9型禽流感病毒等病原体的检测全为阴性;应用该方法对118份临床病料进行检测,结果检出鸭副黏病毒和鸭圆环病毒阳性感染率分别为0.85%和8.47%,无混合感染。本试验建立的二重荧光定量PCR具有快速、特异、敏感和重复性好等优点,适用于鸭副黏病毒和鸭圆环病毒的快速诊断和监测。     

番鸭细小病毒荧光定量PCR方法的建立及初步应用

为建立一种快速检测番鸭细小病毒(MDPV)的方法,本研究根据GenBank中MDPV的REP基因序列,设计一对特异性引物和一条TaqMan探针。对反应条件和试剂浓度进行优化,建立了检测MDPV的荧光定量PCR方法。检测结果表明,该方法检测敏感性达到20 copies,比常规PCR灵敏度高100倍;而且该方法对鸭I型肝炎病毒、鸭圆环病毒、鹅细小病毒、鸭副粘病毒、鸭瘟病毒和禽流感病毒等的检测均为阴性,具有良好的特异性;该方法的批内和批间的检测变异系数均小于2%。对广西地区鸭群收集的118份病料进行检测,其MDPV阳性率为11.02%。结果提示广西地区的鸭群中MDPV的感染比较普遍,建立的荧光定量PCR方法可以用于MDPV的临床快速检测。     

番鸭细小病毒与鸭圆环病毒二重PCR方法的建立

根据基因库中鸭圆环病毒和番鸭细小病毒的基因序列,分别设计了两对特异性引物,通过对二重PCR扩增条件的优化,研究建立了可同时鉴别检测鸭圆环病毒和番鸭细小病毒的二重PCR方法。用该方法对同一样品中鸭圆环病毒和番鸭细小病毒的模板进行PCR扩增,结果均得到了与实验设计相符的351bp（鸭圆环病毒）和474bp（番鸭细小病毒）的扩增条带,而对鸭Ⅰ型肝炎病毒、鹅细小病毒、鸭副黏病毒、鸭瘟病毒和禽流感病毒等病原体的检测全为阴性。敏感性测定结果表明：该二重PCR技术最低能检出100fg的鸭圆环病毒和番鸭细小病毒DNA模板。研究建立的鸭圆环病毒和番鸭细小病毒的二重PCR方法,具有快速、敏感、特异、定量和重复性好等优点,可用于临床上鸭圆环病毒和番鸭细小病毒感染的检测。     

应用套式RT-PCR快速检测鸭坦布苏病毒

鸭坦布苏病毒是新发现的一种可引起鸭产蛋下降、生长迟缓和死亡的黄病毒。目前尚无可靠的快速诊断方法用于该病毒的检测。本研究根据鸭坦布苏病毒E基因序列,设计了2对重叠引物P1、P2和P3、P4,建立了检测鸭坦布苏病毒的套式RT-PCR方法,该套式RT-PCR比一般PCR敏感性高10倍。采用该方法对安徽省、河北省、山东省、浙江省、上海市等地发病鸭场的63份样品进行了检测,阳性检出率为48/63（76.2%）,而病毒分离率仅为13/63（20.6%）。由此表明,与其他方法相比较,本试验所建立的套式RT-PCR方法具有快速、敏感、特异优点,可用于鸭坦布苏病毒的流行病学调查及病毒的检测。     

新型鸭细小病毒SYBR Green I 荧光定量PCR检测方法的建立及初步应用

本研究以新型鸭细小病毒VP3基因保守区域克隆至pMD19-T载体上获得的阳性质粒作为标准阳性质粒,建立一种检测新型鸭细小病毒SYBR GreenⅠ荧光定量PCR方法。结果显示:在5.17×10~1～5.17×10~7拷贝数呈良好的线性关系,相关系数R~2为0.999、斜率为3.595,灵敏度可达到5.17拷贝数;该方法用于检测鸭常见传染病呼肠孤(DRV)、禽流感(AIV)、鸭坦布苏病毒(DTMUV)、鸭病毒性肝炎(DHV)、鸭星状病毒(DAstV)无非特异性扩增,特异性良好;对安徽、山东、江苏等地鸭场采集的疑似病料进行初步检测,发现48份样品中阳性率达70.8%,与普通PCR方法检测结果相比,本研究建立的SYBR Green Ⅰ荧光定量PCR方法更灵敏。本研究成功建立了一种检测新型鸭细小病毒SYBR Green Ⅰ荧光定量方法,为新型鸭细小病毒的监测奠定了坚实基础。     

鸭细小病毒地高辛标记探针的制备与应用

根据GenBank发表的1株鸭细小病毒全基因组序列设计1对特异性引物,利用PCR扩增得到大小为301bp的片段,回收纯化后用地高辛进行标记,制备鸭细小病毒地高辛标记探针。特异性试验表明,该探针仅与鸭细小病毒发生特异性杂交反应,与GPV、MDPV、DcuV、DEV、DHAV-I、H9N2亚型AIV、N-DRV、NDV、TMUV杂交反应均为阴性。敏感性试验表明,该探针对鸭细小病毒核酸的最低检测量为25pg。应用制备的探针对山东、江苏和安徽等地采集的61份患病鸭和30份健康鸭组织进行检测,阳性率分别为97%和0%,与病毒分离结果符合率为98%。上述结果显示,本研究制备的探针特异性强、敏感性高,为该病的诊断和流行病学调查提供可靠的方法。     

检测新型鹅细小病毒的半套式PCR方法的建立及应用

2015年以来山东、江苏等地的樱桃谷肉鸭暴发了一种由新型鹅细小病毒(NGPV)引起的短喙-侏儒综合征(BADS)的疾病,造成了严重的经济损失。为探究该病毒在鸭体内分布规律,本研究根据Gen Bank已登录的NGPV的VP3基因设计了3条引物,建立了检测NGPV的半套式PCR方法。该方法对其它常见鸭病原微生物无特异扩增,特异性好;最低可检出100拷贝/μL的病毒核酸,灵敏度高。采用建立的半套式PCR方法对山东、江苏两地8个樱桃谷肉鸭鸭群120只病死鸭的心脏、肝脏、脾脏、肺脏、肾脏、胸腺、法氏囊、胰腺、脑和胆汁进行检测,结果显示患病鸭群的群体检出率为100%,个体检出率为80.8%(97/120);10种组织脏器中均检出NGPV,其中心脏检出率最高为93.8%,脑组织检出率最低为9.3%。本研究首次对NGPV在鸭体内10个脏器组织的分布进行统计分析,证明了NGPV对樱桃谷鸭具有广泛的组织嗜性。     

一种新型鸭呼肠孤病毒SYBR GreenⅡ荧光定量PCR方法的建立

该研究旨在建立一种快速、敏感和特异性检测新型鸭呼肠孤病毒(Novel duck reovirus,NDRV)的荧光定量PCR诊断方法。本实验以感染新型鸭呼肠孤病毒的鸭组织RNA提取物为模板,根据Gen Bank数据库中呼肠孤病毒S1基因全序列,设计合成了一对特异性引物,PCR扩增基因片段,将其克隆至p ET-30a载体,重组质粒测序并进行同源性分析;以阳性质粒为模板,建立SYBR Green II荧光定量PCR检测方法,并进行敏感性和特异性检测。经测序证实扩增片段与预期目的片段相符,所建立的SYBR Green II荧光定量PCR检测S1的反应在101~108 copies/u L之间具有良好的线性关系,反应的检出下限为10 copies/μL,而H5型禽流感病毒、H9型禽流感病毒、鸡传染性支气管炎病毒、C型鸭肝炎病毒、新城疫病毒、鹅细小病毒、鸭瘟病毒等病毒的检测为阴性,表明该方法敏感、特异。本研究成功建立了SYBR Green II荧光定量PCR检测新型鸭呼肠孤病毒的方法,为新型鸭呼肠孤病毒致病机制和机体免疫保护机制的研究提供了技术平台。     

鸭腺病毒A型TaqMan实时荧光定量PCR检测方法的建立

试验旨在建立鸭腺病毒A型(duck adenovirus A,DAdV-A)TaqMan实时荧光定量PCR检测方法。根据DAdV-A Hexon基因序列设计特异性引物和探针,建立了基于TaqMan探针检测DAdV-A的实时荧光定量PCR检测方法,对其特异性、灵敏性、重复性进行检测,用建立的TaqMan实时荧光定量PCR检测方法和常规PCR方法同时对福建地区临床收集的85份番鸭源病料进行DAdV-A感染的检测,比较其符合率。结果表明,试验成功建立了检测DAdV-A的实时荧光定量PCR检测方法,其扩增相关系数为0.996,扩增效率为99.9%;特异性强,对鸭常见病原(如鸭瘟病毒、鹅细小病毒、番鸭细小病毒、鸭圆环病毒、鸭源大肠杆菌、鸭疫里默氏杆菌和鸭源禽多杀性巴氏杆菌)检测均为阴性;灵敏度高,最低检测限为8.37拷贝/μL;重复性好,组内变异系数和组间变异系数分别为0.54%~1.28%和0.61%~2.39%。对临床送检的85份病料,TaqMan实时荧光定量PCR方法的阳性率为7.06%(6/85),PCR方法的阳性率为5.88%(5/85),且PCR检测的阳性样品经TaqMan实时荧光定量PCR方法检测均为阳性,符合率为100%。本研究建立了基于TaqMan探针检测DAdV-A的实时荧光定量PCR检测方法,为鸭群中开展DAdV-A的分子流行病学研究提供了有效技术手段。     

商会自治的基石——商会自治规范研究

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。     

癸氧喹酯干混悬剂含量测定的改进

采用高效液相色谱法测定癸氧喹酯干混悬剂的含量,在2-250μg/mL范围内,峰面积的常用对数与进样量浓度的常用对数呈良好的线性关系,R^2=1(n=5),平均回收率为99.24%~99.51%,RSD在0.05%~0.28%。此方法分析时间短,样品前处理简便、定量结果准确,重现性好,结果满意,为其质量控制提供了依据。     

猪毛色遗传的研究进展

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。     

Comparison of 2 methods of centesis of the bursa of the biceps brachii tendon of horses

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.     

不同样本商品蜂蜜中硒含量的测定

用硝酸和高氯酸消化蜂蜜,使硒游离出来,在微酸性环境下,硒和2,3-二氨基萘(DAN)生成有较强荧光的物质,用环己烷萃取,在激发波长378nm,荧光波长518nm处测定其荧光强度。蜂蜜中硒含量范围:0.10～0.82μg/g。表明:蜂蜜应视为天然富硒营养品。     

乳酸杆菌益生作用机制的研究进展

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。     

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.     

Mechanism of Action of Probiotic Function of Lactobacilli

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.     

Evaluation of serum concentrations of biomarkers of skeletal metabolism and results of radiography as indicators of severity of osteochondrosis in foals

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.