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1.
CAV与REV共感染SPF鸡对疫苗免疫反应的抑制作用   总被引:3,自引:0,他引:3  
用1日龄SPF鸡人工感染鸡贫血病毒(CAV)和禽网状内皮增生病病毒(REV),探讨病毒感染对鸡体疫苗免疫反应的影响。结果表明,在用禽流感病毒(AIV,H5和H9)疫苗免疫后,CAV与REV单独感染均显著抑制了鸡体对H5和H9亚型禽流感病毒灭活疫苗的HI抗体反应,在CAV与REV共感染后,这种抑制作用更为明显。CAV单独感染后鸡体对新城疫病毒(NDV)和传染性法氏囊病病毒(IBDV)疫苗的免疫反应受到抑制,但与对照组在统计学上的差异不显著,然而,CAV可以显著加重REV感染对鸡体在NDV和IBDV疫苗免疫后抗体反应的抑制作用。从而证实CAV与REV共感染在疫苗免疫抑制上有协同作用。  相似文献   

2.
Z X Xie  H D Stone 《Avian diseases》1990,34(1):154-162
Inactivated Newcastle disease virus (NDV), avian influenza virus (AIV), and infectious bronchitis virus (IBV) antigens were evaluated for immunological efficacy in monovalent and polyvalent vaccines. Vaccinated broilers were bled for hemagglutination-inhibition (HI) tests at 1- or 2-week intervals. Half of the chickens were challenged with the Largo isolate of velogenic viscerotropic (VV) NDV at 8 weeks post-vaccination, and the remainder were challenged with the Massachusetts 41 strain IBV at 9 weeks post-vaccination. Newcastle disease HI titers were reduced significantly (P less than 0.05) from those of monovalent control vaccine groups when IBV antigen was emulsified in mixtures with low (1-3x) concentrated NDV or NDV and AIV antigens. Avian influenza HI titers were significantly (P less than 0.05) lower than those of the control monovalent groups when highly concentrated NDV was part of the polyvalent vaccine. Infectious bronchitis HI titers were higher than those of control monovalent groups in 13 of 15 vaccine groups when IBV antigen was in polyvalent formulations. VV NDV challenge killed all non-NDV vaccinates and induced increased HI titers in NDV vaccinates but no morbidity or mortality. Sixty of 80 IBV vaccinates experienced a fourfold or greater HI titer increase following challenge. All non-IBV vaccinates seroconverted at 1 week post-challenge.  相似文献   

3.
Inactivated canine parvovirus (CPV) and inactivated feline panleukopenia virus (FPV) vaccines were evaluated in dogs. Maximal serologic response occurred within 1-2 weeks after vaccination. Antibody titers then declined rapidly to low levels that persisted at least 20 weeks. Immunity to CPV, defined as complete resistance to infection, was correlated with serum antibody titer and did not persist longer than 6 weeks after vaccination with inactivated virus. However, protection against generalized infection was demonstrated 20 weeks after vaccination. In unvaccinated dogs, viremia and generalized infection occurred after oronasal challenge with virulent CPV. In contrast, viral replication was restricted to the intestinal tract and gut-associated lymphoid tissue of vaccinated dogs. Canine parvovirus was inactivated by formalin, beta-propiolactone (BPL), and binary ethylenimine (BEI) in serum-free media; inactivation kinetics were determined. Formalin resulted in a greater loss of viral HA than either BEI of BPL, and antigenicity was correspondingly reduced.  相似文献   

4.
鸡新城疫、传染性支气管炎、禽流感(H9亚型)三联灭活苗(La Sota株+M41株+Re-9株)(三联苗(Re-9株))为国内首个采用基因重组H9亚型禽流感疫苗株研制的新支流三联灭活疫苗。为研究疫苗上市后的实际应用效果,使用7日龄AA肉鸡和260日龄产蛋期蛋鸡评价三联苗(Re-9株)有效性。结果显示:肉鸡免疫后14 d即可激发抗体,免疫后21 d,新城疫病毒(NDV)、传染性支气管炎病毒(IBV)、H9亚型禽流感病毒(H9 AIV)的血凝抑制(HI)抗体分别达8.6log2、6.2log2、8.3log2,出栏时仍维持在较高水平;于免疫后14 d抽样进行NDV、H9 AIV攻毒,对照组均100%发病或排毒,免疫鸡均可获得100%保护;在蛋鸡上,免疫三联苗(Re-9株)后28 d,NDV、IBV、H9 AIV的HI抗体效价分别达12.0log2、7.8log2、12.2log2,免疫后6个月仍可以维持在较高水平。结果表明:三联苗(Re-9株)在实际应用中免疫效果较好,本研究将为鸡新城疫、传染性支气管炎、H9亚型禽流感的防控提供有力支撑。  相似文献   

5.
60Coγ射线对不同状态不同体积的鸡新城疫病毒(NDV)、H9N2亚型禽流感(H9N2 AIV)和猪繁殖与呼吸综合征病毒(PRRSV)进行辐照,研究60Coγ射线对灭活疫苗中病毒的灭活效果。结果表明,6.0 kGy 60Coγ射线辐照对冷冻和液态下5000和10000 mL的NDV、H9N2亚型AIV和PRRSV均不能灭活,辐照后NDV和H9N2亚型AIV冷冻尿囊液的HA效价降低而液态尿囊液的HA效价升高;液态下,60Coγ射线能够灭活250 mL细胞培养液中的PRRSV,不能灭活250、5000和10000 mL尿囊液中的NDV和H9N2 AIV,250 mL与5000、10000 mL的NDV HA效价间差异显著(P<0.05)。60Coγ射线辐照对液态的PRRSV细胞培养液灭活效果良好,有望用于灭活苗的病毒灭活。  相似文献   

6.
二乙烯亚胺对猪细小病毒的灭活作用   总被引:2,自引:0,他引:2  
使用新型灭活剂二乙烯亚胺(binary ethylenimine,BEI)对猪细小病毒(Porcine parvovirus,PPV)进行了灭活试验,通过ST传代细胞接种法观察病毒灭活后是否出现细胞病变,并结合血凝试验检测灭活效果,确定最佳灭活方法。用3~5日龄乳鼠检测BEI灭活后的病毒培养物和相应制备疫苗的安全性,并用豚鼠检测该灭活工艺制备疫苗的效果,与传统甲醛灭活进行了比较。结果显示,终浓度为1‰的BEI在32℃情况下经20 h即可彻底灭活PPV病毒;BEI灭活的病毒制备的疫苗免疫豚鼠较甲醛灭活病毒产生较高的血凝抑制抗体。  相似文献   

7.
禽流感H9亚型流行毒株交叉免疫保护试验   总被引:3,自引:0,他引:3  
采用北京市农林科学院畜牧兽医研究所1998年-2008年在北京及河北省分离的4株禽流感病毒H9亚型流行毒株,分别制备不同分离毒株灭活疫苗,免疫SPF鸡,进行交叉免疫保护试验。结果表明,用4个不同时期的分离毒株所制备出的灭活疫苗免疫鸡后,各免疫组鸡禽流感(H9亚型)的HI抗体效价均明显上升,所诱导产生的HI抗体效价基本相同;不同时期分离毒株大多产生了较好的交叉保护力。用1998年、2004年及2006年分离的流行毒株制备出的灭活疫苗能够保护2008年流行毒株的攻击。  相似文献   

8.
为了监测鸡新城疫、传染性支气管炎、禽流感(H9亚型)三联灭活疫苗(LaSota株+M41株+SS/94株)对H9亚型禽流感病毒流行毒株的免疫保护效果,采用H9亚型禽流感病毒SS/94株及2009—2010年现地分离的3株H9亚型禽流感病毒对已免疫上述三联灭活苗的SPF鸡进行攻毒试验。结果显示,试验鸡以0.3 mL/只的剂量免疫三联灭活苗后21 d,其H9亚型禽流感病毒的HI抗体效价可达8~11log2,此抗体水平可抵抗2×106EID50的H9亚型禽流感病毒SS/94株、BLCN09株、WDZ09株、YT10株的攻击,攻毒保护率均达90%(9/10)以上。可见,以SS/94株作为禽流感疫苗抗原制备的三联灭活苗具有良好的免疫原性,能使免疫鸡抵抗2009—2010年期间现地分离的多株H9亚型禽流感病毒的攻击。  相似文献   

9.
To analyze the contribution of neuraminidase (NA) toward protection against avian influenza virus (AIV) infection, three different recombinant Newcastle disease viruses (NDVs) expressing hemagglutinin (HA) or NA, or both, of highly pathogenic avian influenza virus (HPAIV) were generated. The lentogenic NDV Clone 30 was used as backbone for the insertion of HA of HPAIV strain A/chicken/Vietnam/P41/05 (H5N1) and NA of HPAIV strain A/duck/Vietnam/TG24-01/05 (H5N1). The HA was inserted between the genes encoding NDV phosphoprotein (P) and matrixprotein (M), and the NA was inserted between the fusion (F) and hemagglutinin-neuraminidase protein (HN) genes, resulting in NDVH5VmPMN1FHN. Two additional recombinants were constructed carrying the HA gene between the NDV P and M genes (NDVH5VmPM) or the NA between F and HN (NDVN1FHN). All recombinants replicated well and stably expressed the HA gene, the NA gene, or both. Chickens immunized with NDVH5VmPMN1FHN or NDVH5VmPM were protected against two different HPAIV H5N1 and also against HPAIV H5N2. In contrast, immunization of chickens with NDVN1FHN induced NDV- and AIV N1-specific antibodies but did not protect the animals against a lethal dose of HPAIV H5N1. Furthermore, expression of AIV N1, in addition to AIV H5 by NDV, did not increase protection against HPAIV H5N1.  相似文献   

10.
Serosurvey of five viruses in chickens on smallholdings in Bangladesh   总被引:1,自引:0,他引:1  
A serologic survey was undertaken in chickens in smallholdings in Bangladesh for avian influenza A virus (AIV), egg drop syndrome '76 virus (EDS'76V), infectious bronchitis virus (IBV), Newcastle disease virus (NDV) and reovirus (RV) in three phases: January 2002-May 2003, September 2003-August 2004, and August 2005-March 2006. Four hundred thirty-six sera collected in the 2nd phase, 295 in the first phase, 755 in the 1st plus 2nd phases and 295 in the 1st phase were investigated for AIV, EDS'76V, IBV and RV, respectively, using enzyme linked immunosorbent assays. All 854 sera collected in the three phases were screened for NDV using hemagglutination inhibition test. In chickens 20% were seropositive to AIV, 3% to EDS'76V, 74% to IBV, 88% to NDV, and 47% to RV. The seroprevalence in flocks was 23% to AIV, 6% to EDS'76V, 79% to IBV, 89% to NDV and 56% to RV. Twenty-five percent chickens had > or = 10log(2)HI titers to NDV.  相似文献   

11.
A recombinant hemagglutinin-neuraminidase (rHN) protein from Newcastle disease virus (NDV) with hemagglutination (HA) activity was expressed in Spodoptera frugiperda cells using a baculovirus expression system. The rHN protein extracted from infected cells was used as an antigen in a hemagglutination inhibition (HI) test for the detection and titration of NDV-specific antibodies present in chicken sera. The rHN antigen produced high HA titers of 213 per 25 µL, which were similar to those of the NDV antigen produced using chicken eggs, and it remained stable without significant loss of the HA activity for at least 12 weeks at 4℃. The rHN-based HI assay specifically detected NDV antibodies, but not the sera of other avian pathogens, with a specificity and sensitivity of 100% and 98.0%, respectively, in known positive and negative chicken sera (n = 430). Compared with an NDV-based HI assay, the rHN-based HI assay had a relative sensitivity and specificity of 96.1% and 95.5%, respectively, when applied to field chicken sera. The HI titers of the rHN-based HI assay were highly correlated with those in an NDV-based HI assay (r = 0.927). Overall, these results indicate that rHN protein provides a useful alternative to NDV antigen in HI assays.  相似文献   

12.
以禽流感病毒A/Chicken/Hubei/327/2004(H5N1)免疫Balb/c小鼠,将免疫鼠脾细胞与SP2/0骨髓瘤细胞融合,用血凝抑制试验筛选细胞培养上清,采用有限稀释法对阳性孔进行克隆,3次克隆后获得7株能稳定分泌抗H5亚型禽流感病毒血凝素单克隆抗体的杂交瘤细胞株,分别命名为1C4,1D4,1E12,2E11,4C12,4G2和5E12。细胞培养上清HI效价为24~27,腹水HI效价可达210~218。所有单抗与禽流感H7和H9亚型标准血凝抗原,新城疫病毒和鸡传染性支气管炎病毒无交叉反应。在细胞上的中和试验显示具有较高的中和效价,获得的单克隆抗体可在禽流感流行病学的监测中发挥重要作用。  相似文献   

13.
D J King 《Avian diseases》1986,30(4):724-727
Newcastle disease virus (NDV) hemagglutination-inhibition (HI) titers were determined for serum samples from eight commercial broiler breeder flocks and their progeny. The chickens sampled had been vaccinated and reared by different producers in different regions of the United States. Breeder flocks had the highest number of NDV-positive HI titers (greater than or equal to 1:10). Eighty percent or more of the samples from six of eight breeder flocks were positive; the geometric mean titers (GMTs) for those six breeder flocks ranged from 19 to 92. Only 3 of 8 broiler flocks had an increased frequency of positive titers and higher GMTs after vaccination. The frequency of positive titers was greater than 80% in only 2 of 8 of the oldest broiler flocks. The number of NDV-negative titers (less than 1:10) increased with age in most broiler flocks, even though all had been vaccinated once or more with live NDV vaccines.  相似文献   

14.
以禽流感H5亚型病毒分别免疫BABL/C小鼠,取其脾细胞与SP2/0骨髓瘤细胞融合,用血凝抑制试验(HI)和间接ELISA检测细胞上清液,结果获得了3株抗禽流感H5亚型病毒特异性单克隆抗体,分别命名为186,1D4,7D1;其中1D4株为抗禽流感H5亚型病毒血凝素特异性单克隆抗体细胞株.186株和7D1株为针对禽流感病毒NP蛋白的单克隆抗体细胞株。经3次亚克隆后,100%杂交瘤细胞保持了分泌抗禽流感病毒抗体的能力。这些单克隆抗体小鼠腹水ELISA效价为10^5,HI效价为2^11-12。研究结果表明,所有这些单克隆抗体仅与相应的禽流感病毒株发生特异性反应,而不与鸡新城疫病毒、产蛋下降综合征病毒、鹅副粘病毒等反应。所有这些单抗在禽流感诊断中将发挥重要作用。  相似文献   

15.
将未浓缩的新城疫抗原分别与未浓缩的、浓缩3倍、浓缩6倍的禽流感抗原混合,并制备成三组鸡新城疫、禽流感(H9N2 HP株)二联灭活疫苗(简称新-流二联灭活疫苗),分别免疫21日龄SPF鸡,每羽0.3 mL,同时设置未免疫的空白对照组,免疫组与对照组均在免疫前及免疫后7、14、21、28、35 d进行采血,检测新城疫和禽流感抗体。结果发现,各免疫组在免后不同日龄的新城疫抗体基本一致,禽流感病毒抗原浓缩倍数越高(即禽流感病毒含量越高)的新-流二联灭活疫苗,免后14、21 d的抗体也越高;从免后21 d开始,各免疫组的禽流感抗体水平差异逐渐减小,免疫后禽流感抗体水平的高低可以反映该疫苗的免疫效果。试验结果表明,该疫苗可以通过浓缩提高抗原病毒含量的方法来提高免后早期抗体水平,取得良好的早期免疫效果。  相似文献   

16.
不同剂型的佐剂对疫苗的免疫效果有较大的影响,本试验旨在对比不同剂型佐剂的新城疫-禽流感(简称"新-流")二联灭活疫苗的免疫效果,从而为生产上选择最佳剂型佐剂应用于新城疫-禽流流感二联灭活疫苗提供依据。分别将油包水型、水包油型、水包油包水型佐剂与新城疫及禽流感灭活抗原乳化成不同剂型的新城疫-禽流感(H9亚型,HP株)二联灭活疫苗,将这三种不同剂型的新城疫-禽流感(H9亚型,HP株)二联灭活疫苗分别免疫一组7日龄SPF鸡。每羽颈部皮下注射0.2 m L,同时设一组未免7日龄SPF鸡作为对照组,各免疫组与对照组SPF鸡于免疫组免后6、10、15、21、28、35 d进行采血,检测新城疫与禽流感抗体水平。结果表明:免疫油包水型疫苗组SPF鸡免疫后新城疫与禽流感抗体上升最快,在免后10、15、21、28、35 d的新城疫与禽流感抗体也最高,其次是免疫水包油包水型的,而免疫水包油型疫苗组的SPF鸡新城疫与禽流感抗体上升最慢,而且在免后10、15、21、28、35 d的新城疫与禽流感抗体也最低。此外,从各免疫组可以看出,在免后6 d时新城疫抗体已开始产生,在1log2以下,而禽流感抗体仍未产生。可见免疫新-流二联苗后,新城疫抗体比禽流感抗体更早产生,油包水型新-流二联苗的免后抗体高于水包油包水及水包油型,而且能持续刺激机体产生高水平抗体,更具优势。  相似文献   

17.
The microbicidal activities of mixtures of quaternary ammonium compounds (QACs) and food additive grade calcium hydroxide (FdCa(OH)2) were evaluated in a suspension test at −20°C using an anti-freeze agent (AFA) containing methanol, or at 1°C, with varying contact time, toward avian influenza virus (AIV), Newcastle disease virus (NDV), fowl adenovirus (FAdV), avian reovirus (ARV), Salmonella Infantis (SI) and Escherichia coli (EC). At −20°C, the mixtures could inactivate AIV and NDV within 30 min, FAdV and ARV within 5 sec, and SI and EC within 3 min, respectively. AFA did not inactivate viruses and bacteria within 30 min and 10 min, respectively. At 1°C, the mixtures inactivated FAdV and ARV within 30 sec, AIV within 10 min, and NDV within 30 min. A mixture of slaked lime (SL) and QAC could inactivate FAdV and ARV within 30 sec, but could not inactivate AIV and NDV even after 60 min at 1°C. SL could not substitute FdCa(OH)2 in order to exert the synergistic effects with QAC. Thus, QACs microbicidal activities were maintained or enhanced by adding FdCa(OH)2. It is hence recommended to use QACs with FdCa(OH)2, especially in the winter season.  相似文献   

18.
An enzyme-linked immunosorbent assay (ELISA) was developed to measure specific antibody activity in sera of chickens exposed to Newcastle disease virus (NDV). A near-linear relationship existed between the log of the corrected absorbance of antisera at a single working dilution and the corresponding observed serum titers as determined by a standard serial-dilution method. Regression analysis was used to construct a standard curve and extract an equation from this relationship. The equation was used to convert corrected absorbance readings of the single working dilution directly into predicted ELISA antibody activity titers. In a comparative study, a correlation (P less than 0.01) was found between ELISA and hemagglutination-inhibition (HI) antibody titers to NDV. ELISA titers were as much as 160 times greater than the HI titers. ELISA was also able to detect much lower levels of antibody activity than the HI test.  相似文献   

19.
20.
为了建立一种简便、快速而且能同时检测新城疫病毒(NDV)和禽流感病毒(AIV)的方法,本试验采用柠檬酸三钠还原法制备胶体金颗粒,分别标记NDV单克隆抗体6C4和AIV单克隆抗体制备免疫检测探针。在硝酸纤维素膜上,用微定量喷头喷好2条病毒检测线(T线)和1条羊抗鼠抗体质控线(C线),制备复合型免疫层析检测试纸条。结果在10 min内,可同时检测出两种病毒。试纸条检测NDV的灵敏度比HA试验结果提高8倍;AIV重组抗原的检测灵敏度为1.7μg/mL。两种病毒互相测试,未出现交叉反应。用缓冲液对照测试结果为阴性。在密封、干燥、低温的条件下,试纸条的灵敏性与特异性没有明显变化。说明本研究建立的NDV和AIV免疫层析检测法具有特异、灵敏、稳定、操作简单等特点,符合现场快速检测的要求。  相似文献   

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