ESAT-6及PPD ELISA检测疫区和非疫区牛结核病的比较研究

本实验克隆、表达了牛结核早期分泌靶抗原蛋白6（ESAT-61抗原,建立了ESAT-6酶联免疫吸附检测方法（ELISA）。同时应用牛结核提纯菌素（PPD）ELISA和ESAT-6-ELISA对采自疫区的641头牛和非疫区的324头牛进行检测,其中PPD-ELISA检测中,疫区有581头阳性牛,阳性率为90．64％,非疫区有2头阳性牛,阳性率为0、62％;ESAT-6-ELISA检测中,疫区有567头阳性牛,阳性率为88．45％,非疫区没有阳性牛。对采自疫区的23例变态反应阳性牛和非疫区的7例变态反应阳性牛进行检测,其中PPD-ELISA检测中,疫区有20头为阳性。与变态反应的符合率为86．90％,非疫区有1头为阳性,与变态反应的符合率为14％;在ESAT-6-ELISA检测中,疫区有18头为阳性,与变态反应的符合率为78．30％,非疫区没有阳性。这些结果表明：ESAT-6-ELISA的敏感性要低于PPD-ELISA;牛结核ELISA在非疫区应用效果较差,在疫区更具有应用价值。     

纯牛奶中抗菌药物残留的检测

为了解山西省交城县各大超市销售纯牛奶中抗菌药物残留情况,随机采购此牛奶50份,分别用TTC法、微生物检测法和酶标免疫分析法进行抗生素残留检测。TTC法检测出阳性率为8％,可疑率为6％;微生物法检测出青霉素类残留阳性率为10％。酶标免疫分析法检测出四环素类阳性率为8％;链霉素残留阳性率为22％;磺胺二甲嘧啶检测全部为阴性。结果表明,交城县各大超市售纯牛奶中有部分存在抗菌药物残留。     

自然感染牛白血病病毒的抗体动态

Kaadeu等(1978)应用免疫扩散试验和免疫荧光法,经多年检测了2352份牛血样,结果表明,牛白血病阳性反应百分率逐年增高。例如,1974—1975年这种阳性反应牛为4.8％,到1978年年来已达到52.6％。1977—1978年他们进行了22次检测,结果查明,在286头牛中57％经常表现白血病阴性反应,仅19.2％为阳性反应。在以后的检测中,在阴性反应总牛数中有10％是阳性,阳性反应牛群中有1.5％为阴性反应。作者的报告还指出,在11次检测中,286头牛中有12.6％或36头表现时而阳性反应,时而阴性反应。     

PCR和核酸探针技术诊断MD和RE的比较研究

分别应用聚合酶链反应(PCR)技术和核酸探针的点杂交技术，对临床鸡肿瘤／可疑肿瘤病料分别进行马立克氏病(MD)和禽网状内皮增生症(RE)的检测。结果MD和RE的PCR检测阳性率分别为81．9％和53．3％，探针点杂交检测的阳性率则分别为77．1％和27．1％。研究的结果表明，两种检测技术都有很高的特异性，相比而言PCR技术检测的敏感性更高，而且更快速、操作更简便、成本更低。     

山东省生猪屠宰企业非洲猪瘟病毒核酸检测能力比对

为客观评价生猪屠宰企业非洲猪瘟检测能力,山东省动物疫病预防与控制中心组织全省319家生猪屠宰企业开展非洲猪瘟病毒核酸检测能力比对.结果显示:有314家屠宰企业反馈结果,其中有225家检测结果完全合格,合格率为71.66％,样品正确率为88.47％(1389/1570);A类和B类屠宰企业合格率分别为79.14％和60....     

浙江省猪弓形体病血清学调查

对浙江省14个县、市的猪弓形体病,采用ELISA进行血清学调查。共检测种猪1228头,阳性率为55.5％。其中,平原地区为63.5％,丘陵地区为51.6％,沿海岛屿为38.9％。有弓形体病流行史的猪场、一般屠宰猪、有弓形体病流行史的户养猪和无明显流行史地区户养猪的阳性率分别为84.5％、53.0％、65.0％和45.5％。     

猪与流行性出血热关系的现地调查

采用RPHI法裣测疫区EHF患者家中饲养的猪的血清,EHF抗体阳性率为7％,对照组为1％,两组有显著差异,P值<0.05。从猪肺及肾组织中检测EHF抗原,采用免疫荧光法,猪肺及肾阳性率分别为5.33％和10％,总阳性率为5.88％;采用免疫组化法,猪肺及肾阳性率分别为13.33％和50％,总阳性率为17.64％,猪抗体阳性的养猪户和猪抗体阴性养猪户人血清中EHF抗体检测,采用免疫荧光法,阳性率分别为16.66％和1.49％,两组有非常显著差异,P<0.01。养猪户与非养猪户人血清中EHF抗体检测阳性率分别为7.33％和0.99％。两组有显著差异,P<0.05。猪抗体阴性的养猪户EHF病人家属血清与对照正常人群血清中EHF抗体阳性率分别为1.49％和0％,两组无差异。     

规模化猪场母猪群PRV抗体血清学调查

采用美国IDEXX公司生产的Herdchek PRV gl抗体检测试剂盒和DHerd Chek PRV gB抗体检测试剂盒对来自于20个种猪场母猪群的血清分别进行野毒抗体和免疫抗体检测。结果显示,有10个猪场的样品均为野毒阴性或野毒感染率较低,其中7个场的PRV免疫抗体合格率均在90％以上,另外有两个场的抗体合格率在80％以上。但对于野毒感染率均在10％以上另外10个场,有3个场由于高野毒阳性率（84％～100％）造成40倍稀释后免疫抗体仍然100％阳性,其余7个场样品阳性率都在20％～73％之间。从上面20个猪场的检测结果来看,管理良好的种猪群可以做到无野毒感染且免疫合格率达到90％以上。     

牛环形泰勒虫ELISA裂殖体抗原制备和应用研究

本文报道了牛环形泰勒虫(Theileria annulata(简称环泰虫)裂殖体抗原的制备和ELISA在诊断环泰虫病、检测免疫牛抗体水平和确定虫种间血清学关系等方面的应用。应用冻融研磨法制备的抗原进行ELISA,检测25头份带虫牛血清,阳性符合率为96％,检测30头份阴性牛血清,阴性符合率为100％;一个样本重复性试验的变异系数为9.52％,多个样本重复试验的结果基本一致。表明ELISA具有较高的特异性和重复性,ELISA检测环泰虫疫区牛,阳性检出率为61.02％(镜检法为38.98％)。ELISA值的高低,与环泰虫带虫牛的红细胞染虫率呈正相关。检测49头份非疫区牛血清,结果均为阴性。用作检测免疫牛抗体水平,32头份重环泰虫裂殖体细胞胶冻苗免疫的牛血清,7个月后ELISA值仍明显高于健牛(未免疫),有62.5％在阳性范围内。检测其他种属虫体血消.不与伊氏锥虫、贝氏贝诺孢子虫和牛肉孢子虫血清发生交叉反应。检测瑟氏泰勒虫血清,有11/12的阳性反应率,初步证实环泰虫与瑟氏泰勒虫有密切的血清学关系。     

猪流行性腹泻病毒、传染性胃肠炎病毒、A群轮状病毒和嵴病毒多重RTPCR检测方法的建立及临床应用

本研究建立了可同时检测猪流行性腹泻病毒（Porcineepidemicdiarrheavirus,PEDV）、传染性胃肠炎病毒（TransmissiblegastroenteritisVirus,TGEV）、A群轮状病毒（GroupArotavirus,GARV）和猪嵴病毒（Porcinekobu—virus）的多重RT—PCR方法。检测中,建立的多重RT—PCR方法能够检测到500Pg的TGEV、PEDV、GARV和猪嵴病毒等量混合RNA模板,与常规的单一RT—PCR检测结果基本相同（检测TGEV、PEDV、GARV和猪嵴病毒的灵敏性分别为1000A、1000／6、93．33％和96．67％,特异性均为i00％）。结果表明,建立的多重RTPCR方法敏感性和特异性良好,可作为临床上猪病毒性腹泻病因快速、高效的诊断工具。应用该方法对2010—2012年华中地区190份腹泻仔猪样本进行检测,PEDV、TGEV、GARV和猪嵴病毒的阳性率分别为62．11％、0．53％、7．37％和82．11％。混合感染方面,PEDV和猪嵴病毒混合感染率为47．89％,PEDV和GARV混合感染率为4．74％,GARV和猪嵴病毒混合感染率为7．37％,PEDV、GARV和猪嵴病毒混合感染率为4．74％,未发现TGEV与其它3种病毒的混合感染情况。另外,有27份样本中仅检出PEDV（14．21％）,57份样本只检出猪嵴病毒（30％）。分析表明,我国自2010年底大面积暴发的病毒性腹泻是多病原混合感染造成的,主要病原为PEDV,猪嵴病毒在其中所起作用尚待进一步验证和研究。     

鸡痘病毒活疫苗污染禽网状内皮组织 增生症病毒的间接免疫荧光法检测研究

通过向无外源病毒污染的鸡痘病毒活疫苗中添加不同剂量的禽网状内皮组织增生症病毒(REV),然后用间接免疫荧光法(IFA)进行检测,确定了该IFA方法的最低检出量为每500羽份疫苗中污染20 TCID_(50)的REV。使用该方法对国内16家企业生产的60批鸡痘病毒活疫苗进行了检验,结果显示2个企业生产的4批疫苗REV检测为阳性。随机选取5批IFA检测阴性样品和4批IFA检测阳性样品,按鸡检查法进行外源病毒检验,结果两种方法对REV污染的检测结果的符合率为100%。     

INFECTION STUDIES ON A RETICULOENDOTHELIOSIS VIRUS CONTAMINANT OF A COMMERCIAL MAREK''S DISEASE VACCINE

Reticuloendotheliosis virus (REV) was isolated in cell cultures from commercial Marek's disease (herpesvirus of turkeys) vaccine and re-isolated from the organs of vaccinated chickens. Runting and feathering abnormalities were produced when 1-day-old specific pathogen free chickens were inoculated with REV. Histopathological lesions in infected chickens were hypoplasia of the thymus, bursa and spleen, and inflammation of the proventriculus, kidneys and liver. Serological responses to REV were detected by the indirect immunoflorescence test in chickens directly inoculated with contaminated vaccine, and spread of REV infection to in-contact chickens was demonstrated by histopathological and serological investigations.     

Relative efficiency of techniques for detecting avian reticuloendotheliosis virus as a vaccine contaminant

Three techniques were compared for sensitivity in detecting reticuloendotheliosis virus (REV) in a deliberately contaminated Marek's disease vaccine. The most sensitive and rapid test was the indirect fluorescent antibody test (FAT). The indirect immunoperoxidase test, although simple to perform and only marginally less sensitive than the FAT, was difficult to interpret at low levels of REV. Using immunoelectron microscopy, virions were seen only after three subcultures and then not to the same level as that detected by the FAT or immunoperoxidase test. Serum raised against the HPRS-1 strain of REV detected other strains of this virus in the FAT.     

禽网状内皮组织增生病病毒感染性引起的鸡群免疫抑制

1999年8月，江苏省泰安州市某AA肉用型鸡父母代种鸡群呈现生长缓慢，鸡新城疫疫苗免疫注射后HI效价不高及多发性腹膜炎，心包炎等免疫抑制性症状，55日龄时，随机从4只患鸡采集血浆样品接种鸡胚成纤维细胞，7d后在间接荧光抗体反应中均对网状内皮增生病病毒（REV）的单克隆抗体11A25呈强阳性反应，结果表明，该鸡各的免疫抑制状态主要由REV的早期感染及其持续发现毒血症所引起。     

网状内皮组织增殖病病毒感染SPF雏鸡外周血液T,B淋巴细胞数量变化

应用ＳＰＡ菌体花环法检测网状内皮组织增殖病病毒（ＲＥＶ）感染ＳＰＦ雏鸡外周血液Ｔ、Ｂ淋巴细胞数量动态变化。结果发现，１日龄ＳＰＦ雏鸡感染ＲＥＶ后７～４９ｄ外周血液Ｔ淋巴细胞数量，１４～４９ｄＢ淋巴细胞数量均明显低于对照组。表明感染ＲＥＶ的ＳＰＦ雏鸡外周血液的细胞免疫和体液免疫水平均下降。     

Monoclonal-antibody-mediated enzyme-linked immunosorbent assay for detection of reticuloendotheliosis viruses

An enzyme-linked immunosorbent assay (ELISA) is described for the detection of reticuloendotheliosis viruses (REVs). The assay uses a mixture of monoclonal antibodies (MCAs) prepared against a 62-kilodalton REV envelope glycoprotein (gp62) to capture antigen, rabbit anti-REV serum as detection antibody, and peroxidase-conjugated anti-rabbit IgG as indicator antibody. The MCAs were reactive with REV strain T, chick syncytial virus, and duck infectious anemia virus but unreactive against Marek's disease and avian leukosis viruses. The ELISA was compared with complement fixation test and REV immunofluorescent assay of infected fibroblasts, plasmas, and egg albumen from infected chickens. The lower limit of gp62 detection was about 120 ng of REV protein. Limit dilution of infectious REV was detected after 7-8 days of cultivation of infected fibroblasts.     

山东省肉种鸡群三种家禽肿瘤性疾病流行病学调查

为调查山东省家禽肿瘤性疾病的流行情况,本研究以血清学、病理组织学、免疫组织化学、病原学等检测手段,在山东省境内17家AA种鸡场进行检测.血清学试验结果显示:马立克氏病病毒(MDV)平均抗原阳性率为1.87%;禽白血病病毒J亚群(ALV-J)和网状内皮组织增生症病毒(REV)平均抗体阳性率分别为9.52%和39.78%;双重及三重感染,MDV+ALV-J、MDV+REV、ALV-J+REV及MDV+ALV-J+REV感染率分别为1.12%、1.21%、3.92%和0.65%.对57羽疑似肿瘤病的病鸡检测显示:MDV、ALV-J和REV的抗体阳性率分别为19.3%、47.37%和57.89%;MDV+ALV-J、MDV+REV和ALV-J+REV的双阳性率分别为1.75%、3.5%和19.3%;无三重感染.病理组织学观察显示:病鸡体内既有各病毒引起的单纯肿瘤,也有双重肿瘤共存的现象.免疫组织化学检测显示,MDV、ALV-J和REV抗原阳性信号在病鸡中的比例分别为38.6%、54.39%和28.07%.PCR检测结果表明:MDV、ALV-J和REV的阳性率分别为43.86%、64.91%和33.33%;MDV+ALV-J、MDV+REV、ALV-J+REV和MDV+ALV-J+REV阳性率分别为15.79%、10.53%、12.28%和7.02%.本研究结果表明,山东省境内AA肉鸡群中仍存在较高的肿瘤性病毒感染率.     

免疫组织化学法与间接免疫荧光法对REV抗原定位的比较

本研究分别用免疫组织化学(IHC)法、间接免疫荧光(IFA)法对肿瘤病鸡不同脏器中的禽网状内皮增生病病毒(REV)进行了检测,旨在为两种REV抗原定位方法的应用提供实验依据.采用REV SD1005分离株人工接种1日龄海兰褐鸡,分别采取28日龄肿瘤病鸡的肿瘤、法氏囊、骨髓、肝脏、心脏、脾脏、腺胃的新鲜切面在洁净盖玻片上触片,同时制备其病理组织连续切片,分别用IHC法、IFA法对触片和切片进行REV检测.结果显示,两种用于抗原定位的染色方法检测结果完全一致,均可对病鸡的肿瘤、法氏囊、骨髓、肝脏、心脏、脾脏、腺胃等组织中存在的REV进行定位,依据染色后的阳性细胞感染率可判断REV的组织嗜性.本研究表明,IHC法与IFA法均可用于检测不同脏器中的REV,并具有良好的特异性、低背景和简便快速的特点.但相对于IFA法,IHC法更经济实用并且实验材料易于保存,因此可以在REV抗原定位研究中推广应用.     

从表现腺胃炎的病鸡中分离到1株网状内皮增生症病毒

从表现传染性腺胃炎的病鸡中分离到 １ 株病毒。该病毒呈球形,真径 ８０～１００ ｎｍ ,有囊膜。将病料接种于鸡胚成纤维细胞,分别用单克隆抗体免疫荧光试验、酶联免疫吸附试验,证明该病毒为网状内皮组织增生症病毒。用细胞培养物接种于 １ 日龄健康鸡,复制出与临床完全相同的症状。     

Molecular characterization of reticuloendotheliosis virus insertions in the genome of field and vaccine strains of fowl poxvirus

Evidence of the widespread occurrence of reticuloendotheliosis virus (REV) sequence insertions in fowl poxvirus (FPV) genome of field isolates and vaccine strains has increased in recent years. However, only those strains carrying a near intact REV provirus are more likely to cause problems in the field. Detection of the intact provirus or REV protein expression from FPV stocks has proven to be technically difficult. The objective of the present study was to evaluate current and newly developed REV and FPV polymerase chain reaction (PCR) assays to detect the presence of REV provirus in FPV samples. The second objective was to characterize REV insertions among recent "variant" FPV field isolates and vaccine strains. With REV, FPV, and heterologous REV-FPV primers, five FPV field isolates and four commercial vaccines were analyzed by PCR and nucleotide sequence analysis. Intact and truncated REV 5' long terminal repeat (LTR) sequences were detected in all FPV field isolates and vaccine strains, indicating heterogeneous REV genome populations. However only truncated 3' LTR and envelope sequences were detected among field isolates and in one vaccine strain. Amplifications of the REV envelope and 3' LTR provided strong evidence to indicate that these isolates carry a near intact REV genome. Three of the four FPV vaccine strains analyzed carried a solo complete or truncated 5' LTR sequence, indicating that intact REV provirus was not present. Comparison of PCR assays indicated that assays amplifying REV envelope and REV 3' LTR sequences provided a more accurate assessment of REV provirus than PCR assays that amplify the REV 5' LTR region. Therefore, to differentiate FPV strains that carry intact REV provirus from those that carry solo 5' LTR sequences, positive PCR results with primers that amplify the 5' LTR should be confirmed with more specific PCR assays, such as the envelope, or the REV 3' LTR PCR.