ELISA检测方法在禽白血病净化中的应用

禽白血病(Avian Leukosis,AL)是由反转录病毒科α肿瘤病毒属禽白血病病毒/肉瘤病毒群病毒(ALV/RSV)引起的禽类多种肿瘤性疾病的总称,感染率高,发病率低,是危害养鸡业的主要疾病之一。禽白血病对种鸡群的危害巨大,且目前尚无商品化疫苗,只能依靠对种鸡群的净化进行防控。至今人类还不能有效的预防和治疗本病,控制禽白血病的主要方法是通过病原检测,淘汰阳性鸡,净化种群。国内外相继建立了多种检测禽白血病的方法,其中ELISA法能高效的检测到蛋清中的ALV抗原,具有敏感、简便、快捷、适用于大面积检测的特点,在种群净化中得到了广泛的应用,但ELISA诊断试剂盒在我国还未实现商品化。在未来禽白血病的净化将通过ELISA检测方法来实现。     

禽白血病研究进展

禽白血病(Avian leucosis,AL)是由禽白血病病毒(Avian leukosis virus,ALV)和禽肉瘤病毒(Aviansarcomavirus,ASV)群(或称为"禽白血病/肉瘤病毒群",现在大都称为"禽白血病病毒")中的病毒引起的以禽类造血组织中某些细胞成分增生为主的肿瘤性传染病的统称~([1~2,32])。禽白血病已被我国列为二类动物疫病~([3])。ALV感染鸡表现发育迟缓、免疫抑制、生产性能下降、多组织肿瘤甚至死亡等,而且还间接造成其他疫苗的免疫失败,从而造成较为严重的损失。因此,禽白血病严重威胁我国肉鸡和蛋鸡及种鸡的生产。但至今还不能有效治疗本病,控制禽白血病的主要方法是通过病原检测,淘汰阳性鸡,净化种群。国内外相继建立了多种检测禽白血病的方法,其中ELISA法能高效地检测到蛋清中的ALV抗原,具有敏感、简便、快捷和适用于大面积检测的特点,在种群净化中得到了广泛的应用。随着我国养禽业的发展以及科研、生产和检疫的需要,建立高效、实用的禽白血病检测方法,研究和控制本病将是今后的重要任务。文章就禽白血病的病原学、致病机制、流行病学、临床症状与病理变化、诊断及防制等方面的研究进展进行了综述。     

禽白血病对养鸡业的影响及防控

禽白血病是由反转录病毒科禽白血病肉瘤病毒群病毒引起的禽类多种肿瘤性疾病的总称,本病在世界各地均有发生。该病能引起鸡只的死亡、淘汰,造成多个组织的肿瘤,导致免疫抑制,降低鸡的生产性能,污染鸡胚或鸡胚来源的细胞作为原材料生产的疫苗。鉴于禽白血病造成的重大经济损失,我国政府将其列为二类动物疫病。控制该病的主要手段是对鸡进行ALV的检测,淘汰带毒的种鸡,通过不断的净化达到洁净种群的目的。     

禽白血病研究进展

<正>禽白血病(Avian leucosis,AL)是由反转录病毒科(Retroviridae)禽白血病/肉瘤病毒群病毒(Avian leukosis/sarcoma virus,ALV)引起的禽类多种肿瘤性疾病的总称。本病在世界各地均有发生,是危害养禽业的主要疾病之一。ALV导致的经济损失表现在三个方面:一是产生肿瘤,导致鸡的死亡;二是     

鸡白血病的防治

鸡白血病由禽白血病/肉瘤病毒群中的病毒感染所引起,归属于肿瘤性疾病,主要发生于性成熟后的鸡,一年四季都可发生,鸡群发生应激时可促发本病。病鸡感染类型有多种,临床以淋巴细胞白血病、成红细胞白血病、成髓细胞白血病和骨髓细胞白血病等最为常见,主要表现全身症状;本病没有特效药物治疗,临床一定要注重预防,加强鸡场的消毒和净化,同时做好蚊蝇及老鼠的防范工作。     

禽白血病的流行特点及其防控

禽白血病是由禽白血病/肉瘤病毒群中的病毒引起的禽类的多种肿瘤性疾病的统称。本病感染率高,发病率低,是危害养鸡业的主要疾病之一,以在成年鸡中产生淋巴样肿瘤和产蛋量下降为主要特征。本文从该病的病原、流行病学特点、临床症状、诊断与防控等方面进行阐述,以期为科学防控禽白血病提供参考。     

河北省蛋鸡群ALV p27抗原ELISA检测

<正>禽白血病(Avian Leukusis,AL)是由反转录病毒科禽白血病/肉瘤病毒群病毒引起的禽类多种肿瘤性疾病的总称,可引起感染鸡免疫抑制和多组织器官发育迟缓、萎缩以及肿瘤等,造成鸡的生产性能下降甚至死亡,由鸡分离的ALV划分为A、B、C、D、E、J六个亚群。自2002年蛋鸡群发现禽白血病以来,全国各地频发,特别是自2009年以来,湖北、山东等地鸡白血病疑似病例频发,鸡群ALV的感染率高达60%,病死率高达50%以上~([1])。崔治中报道,     

麻黄鸡核心育种群中不同禽白血病检测方法的效果比较分析

禽白血病(Avian leukosis,AL)给我国肉鸡产业带来了严重危害,作为我国重要的地方优质鸡品种之一的麻黄鸡也深受其害,本试验采用病毒分离、IDEXX禽白血病抗原检测试剂盒、禽白血病快速检测试纸条等方法对广东某鸡场麻黄鸡核心育种群进行禽白血病净化工作,经过3个世代的净化,种公鸡的禽白血病P27抗原阳性率下降明显,但雏鸡的净化整体来看效果不佳。经分析表明,禽白血病快速检测试纸条产品质量稳定性不好,导致检测结果不可靠,用病毒分离和IDEXX试剂盒检测到的阳性率比较一致且稳定。     

一起蛋鸡淋巴细胞性白血病的诊断

禽白血病(Avian Leukosis,AL)是由禽白血病/肉瘤病毒群中的病毒引起的一种以成年禽类产生淋巴样肿瘤和产蛋量下降为特征的肿瘤性疾病。本病常呈渐进性发生和持续的低死亡率,但可使肉鸡群的增重率和蛋鸡群的产蛋率严重降低,尤其是使鸡群抗病力下降,对其它病原微生物的易感性增高     

蛋种鸡场禽白血病净化水平传播控制技术

禽白血病(AL)是由白血病/肉瘤病毒群中的病毒引起禽类多种肿瘤型疾病的总称。禽白血病的水平传播相对其它疾病如禽流感、新城疫等相对较弱,水平传播主要发生在孵化期间和出雏后的前两周内,控制禽白血病水平传播的关键分孵化环节和生产环节两个阶段。本文结合峪口禽业公司在禽白血病净化工作中实施的孵化     

An enzyme-linked immunosorbent assay for detection of antibodies to exogenous avian leukosis virus

A microplate enzyme-linked immunosorbent assay (ELISA) for detecting antibodies to avian leukosis virus (ALV) of subgroups A and B in infected chickens was developed with the use of Rous-associated virus (RAV)-1 (subgroup A) and RAV-2 (subgroup B) antigens purified by sucrose-gradient centrifugation. The antigen was used for ELISA after treatment with Triton X-100. In the ELISA, the subgroup viral antigen reacted strongly with homologous antiserum but also reacted with heterologous antiserum. Tests with serum absorbed with purified homologous and heterologous virus and tests for antigen-blocking by group-specific antibodies to ALV revealed that the reaction was caused mainly by subgroup-specific antibodies. The ELISA was 8 to 32 times more sensitive than the virus-neutralization (VN) test and detected antibodies to ALV earlier than the VN test in chickens infected experimentally with RAV-1 and RAV-2. In field application of the ELISA, 44.2% of 484 chicken sera were positive for RAV-1 and/or RAV-2 antigen, and 80.4% of flocks were positive. These findings indicate that ELISA is superior to the VN test in sensitivity, simplicity, rapidity, and applicability for large-scale field surveys for ALV infection.     

Testing and management of a specific pathogen free chicken flock with special reference to avian leukosis virus infections.

A specific pathogen free (SPF) chicken flock was reared in isolation under laboratory conditions during five years and continuously tested for presence of specified avian pathogens. The potential occurrence of avian leukosis virus (ALV) was most thoroughly examined. The RIF and neutralization tests were unequivocally negative. Radioimmunoassay was used for detecting the presence of the major protein (gs-a) of the group-specific antigen of avian onoorna viruses. This test seemed to he well suited for checking ALV infections in chicken flocks whereas the COFAL (complement fixation avian leukosis) test was considered unreliable for this purpose. Yolk and serum from SPF chickens were negative for anti-gs-a antibodies measured by the radioimmunoassay; immunized or naturally infected birds showed anti-gs-a amounts correlating with the neutralizing titre. Besides, the flock was regularly tested for presence of seven other contagious avian pathogens. There was no evidence of infection.SPF chicken flock; avian leukosis; laboratory diagnosis of avian leukosis virus infections.     

苏皖地区规模化鸡场禽白血病净化的初步研究

基于苏皖地区禽白血病(AL)流行病学调查结果,本研究参考国际AL净化方案,针对该病在苏皖地区的流行特点,选择代号为DYAH91和DYJS31的两个规模化地方品系鸡群开展了禽白血病净化初步研究。经过一个世代的净化更替,DYAH91鸡群p27抗原阳性率由14.4%下降到8.1%,p27抗体阳性率由3.4%下降到1.0%,A/B亚群抗体阳性率由5.7%下降到2.2%,病毒分离阳性率由3.1%下降到0.45%;DYJS31鸡群,p27抗原阳性率由40.7%下降到2.8%,p27抗体阳性率由18.7%下降到3.3%,A/B亚群抗体阳性率由10.2%下降到1.4%,J亚群抗体由1.7%下降到1.4%,病毒分离阳性率由4.1%下降为0。以上结果表明通过净化程序的实施,鸡群ALV阳性率显著下降,净化方案效果确实。     

禽白血病病毒双抗体夹心ELISA检测方法的建立和标化

利用原核表达的禽白血病病毒(ALV)P27蛋白作为抗原制备的单抗作为包被抗体,以制的酶标兔抗P27作为酶标抗体,在国内首次建立了检测ALV抗原的双抗体夹心ELISA方法.该方法对禽白血病P27抗原的最小检出量为5 ng/mL,通过统计学试验证明自制的诊断试剂具有良好的特异性和稳定性.与IDEXX试剂盒的平行实验确定自制诊断试剂S/P＞O.17为阳性判定标准.应用此方法对北京附近鸡场对抽样检测687份蛋清样品,检测结果与IDEXX的禽白血病抗原检测试剂盒符合率达到100%.     

Development and validation of an ELISA for detecting antibodies to Eimeria tenella in chickens

The aim of this study was to develop and validate an ELISA for detecting chicken antibodies to Eimeria tenella. An initial comparison of merozoite and sporozoite antigen preparations revealed few differences in their ability to monitor the onset, kinetics and magnitude of the antibody response suggesting that both antigens would be equally useful for development of an ELISA. Furthermore the cross-reactivity of these antigens with sera from birds infected with chicken Eimeria species was similar. The merozoite antigen was selected for further evaluation because it was easier to prepare. Discrimination between sera from birds experimentally infected with E. tenella and birds maintained in an Eimeria-free isolation facility was excellent. In sera collected from free-range layers and commercial broilers there also appeared to be clear discrimination between infected and uninfected birds. The ELISA should prove useful for monitoring infectivity in vaccination programmes in layer and breeder flocks and for assessing the effectiveness of biosecurity measures in broiler flocks.     

Detection of avian leukosis virus antigens by the ELISA and its use for detecting infectious virus after cultivation of samples and partial characterization of specific pathogen-free chicken lines maintained in this laboratory.

An enzyme-linked immunosorbent assay (ELISA) for detecting avian leukosis virus (ALV) antigens was developed with rabbit anti-ALV serum. The ELISA detected purified ALV of subgroups A and B at a concentration of 0.4 ng/well and about 10(3) infectious units/well estimated by a resistance-inducing factor (RIF) test, and antigens in culture fluids from chicken embryo fibroblasts infected with subgroups A, B or E of ALV. These results showed that common antigens among the subgroups were detected by the ELISA. When virus titration was performed, virus infectivity could be determined by the ELISA within 7 days after cultivation. The titer was similar to that obtained by the RIF test on 19 days after 3 subcultures. These results indicate that the ALV-isolation test by the ELISA was superior to the RIF test in rapidity and applicability to large-scale field trials. Four specific pathogen-free (SPF) chicken lines maintained in this laboratory were examined for endogenous ALV antigens by the ELISA. Sera from laying hens had considerably high absorbance (A) values, whereas albumen samples showed low A values except for some samples (7/40 hens). Although most of sera from 1-day-old SPF chicks showed lower A values than those from laying hens, some sera showed A values as high as those from viremic chicks in 2 lines. Endogenous ALV was isolated from sera from laying hens (6/40) and their albumens (4/7) with high A values. Two SPF chicken lines were found to produce endogenous virus at a high frequency.     

种鸡场鸡白血病净化的研究(Ⅲ)-ALV检测不同样品种鸡场净化效果的比较

应用双抗体夹心酶联免疫吸附试验 (DAS- EL ISA)在种鸡白血病的净化中 ,针对同一种鸡群 ,同时采用蛋清和肛拭作为试验材料 ,实验反映的结果不同 ;将产第一枚蛋为阳性的鸡隔离饲养 ,检测其以后蛋中 AL V的状况 ,结果发现 :在随后的 2 5天左右的每一枚蛋清中都能检测到 AL V:在不同种鸡场分别采用蛋清、蛋清和肛拭同时作试验样品进行净化 ,跟踪结果发现 :在不同种鸡场中 ,AL V阳性感染率都有不同幅度的下降。另一方面 ,检测雏鸡的胎粪 ,淘汰阳性者 ,到其产蛋期抽检蛋清 ,该群鸡 AL V阳性率有所下降     

Cases of swollen head syndrome in broiler chickens in Greece

From 50 commercial broiler flocks included in a study concerning respiratory disease, signs of swollen head syndrome (SHS) were shown in eight. Postmortem examination was performed in eight birds showing signs of SHS from each flock. The trachea and head from each bird were collected for laboratory investigation. An enzyme-linked immunosorbent assay (ELISA) was used for the detection of viral and avian mycoplasma antigens in the trachea, and bacteriologic examinations were performed from the infraorbital sinuses of the infected birds. According to the ELISA results, the most frequently detected antigen in the trachea was Mycoplasma synoviae (six flocks, 75%), followed by infectious bronchitis virus (IBV) (five flocks, 62.5%), avian adenovirus (four flocks, 50%), avian reovirus (three flocks, 37.5%), Mycoplasma gallisepticum (one flock, 12.5%), and Newcastle disease virus (NDV) (one flock, 12.5%). Turkey rhinotracheitis (TRT), infectious laryngotracheitis, and avian influenza viral antigens were not detected. Experimental assays for characterization of NDV and IBV isolates showed that they were strains of low virulence (evidently vaccine strains). Bacteriologic examinations from the infraorbital sinuses of the affected birds resulted in the isolation of Escherichia coli (seven cases, 87.5%) and Staphylococcus spp. (one case, 12.5%). It is evident that TRT virus did not play a causal role in SHS in commercial broiler flocks in Greece, but in this condition, other viruses (IBV, NDV), mycoplasmas, or bacteria may be involved, and environmental conditions seem to be essential to the occurrence and severity of the disease.     

Diagnosis of myeloid leukosis induced by a recombinant avian leukosis virus in commercial white leghorn egg laying flocks

Commercial white leghorn egg layer flocks being used to produce fertile eggs for human vaccine production exhibited dramatically low peaks in egg production, two to four times higher than normal weekly mortality, and high numbers of cull, nonlaying birds after the onset of sexual maturity. These lower production characteristics could not be associated with management-related problems. Gross lesions of cull and fresh dead birds necropsied showed approximately 60% lacked ovarian activity and had lesions of a bacterial bursitis or synovitis, whereas the other 40% had tumors of the viscera but not of the bursa of Fabricius. Histologic examination of tumor-containing tissues showed lesions typical of myelocytomatosis. The diagnosis of myeloid leukosis was confirmed by the isolation of a recombinant avian leukosis virus (ALV) containing the LTR of subgroup J and the envelope of subgroup B ALV. A positive polymerase chain reaction with primers specific for the 3' untranslated region LTR confirmed the presence of LTR of ALV-J. The source of infection with this recombinant ALV was not determined; however, it is likely that commingling of the day-old egg-type chicks with ALV-J-infected meat-type chicks in a common hatchery had contributed to this outbreak.