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2017年7月7日,农业部决定对全国家禽开展H7亚型流感免疫。为了掌握重组禽流感病毒(H5+H7)二价灭活苗的免疫效果,2017年8—9月,重庆市动物疫病预防控制中心进行了控制性试验和大面积临床监测。控制试验结果表明:首免15 d后,H7亚型禽流感抗体合格率可达70.00%,H5亚型抗体合格率仅为10.00%;首免22 d后,H7亚型禽流感抗体合格率达到93.33%,H5亚型抗体合格率达到60.00%;该疫苗未出现严重免疫副反应;H7亚型禽流感抗体产生的时间早于H5亚型。随机选取5个区县,采集414份免疫血清进行监测。结果显示:二价灭活苗免疫21 d后,H5和H7亚型禽流感抗体平均合格率分别为92.27%和76.00%;5个区县的抗体水平存在差异;蛋鸡抗体水平高于肉鸡。控制试验及临床监测结果提示,该疫苗免疫效果确实,但部分区县仍存在免疫抗体水平不高的养禽场。因此,在新旧疫苗交替使用期间,各地应高度重视高致病性H5和H7亚型禽流感防治工作,尤其是肉鸡。 相似文献
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《畜牧兽医科技信息》2019,(12)
为掌握鸭免疫重组禽流感三价灭活疫苗后的免疫效果情况,在蛋鸭养殖场采集一次免疫三价灭活苗21d后的蛋鸭血清30份,采用血凝与血凝抑制试验进行抗体水平检测,结果为H5N2亚型禽流感r FJ56株免疫抗体合格为83.33%,H5N2亚型禽流感r SD57株免疫抗体合格为96.67%,H7N9亚型禽流感r GD76株免疫抗体合格为80.00%。结果表明该疫苗一次免疫后效果良好,能达到禽流感防治规范免疫合格率70%以上的要求。 相似文献
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用5种不同的禽流感疫苗以不同免疫剂量、不同免疫次数接种乌昌地区三黄鸡,定期检测禽流感免疫抗体,结果表明,重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)、Inactivated Vaccine of Avian Influenza(H5N2)和禽流感(H5+H9)二价灭活疫苗(H5N1Re-1+H9N2 Re-2株)等3种疫苗均能刺激机体产生良好的免疫抗体,而禽流感-新城疫重组二联活疫苗(rL-H5株)和禽流感重组鸡痘病毒载体活疫苗(H5亚型)的免疫抗体十分低下。经不同免疫次数的比较试验表明,重组禽流感病毒灭活疫苗(H5N1亚型,Re-1株)、Inactivated Vaccine of Avian Influenza(H5N2)和禽流感(H5+H9)二价灭活疫苗(H5N1Re-1+H9N2 Re-2株)二次免疫的H5抗体水平明显高于经一次免疫的抗体水平,且免疫持续期长。 相似文献
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为了解H5亚型重组禽流感Re-6株灭活疫苗在鸡、鸭免疫后的抗体消长规律,本实验分别选择一个鸡场和鸭场开展了临床免疫实验。实验鸡群于14日龄首免单价疫苗(Re-6株)和H5亚型二价疫苗(Re-6株+Re-4株)后,在30日龄~200日龄不同时间点采血检测Re-6抗体,结果表明,二价疫苗比单价疫苗免疫后的Re-6免疫抗体产生早、效价高、抗体整齐度好;40日龄二免后20 d,二价疫苗和单价疫苗的Re-6免疫抗体消长规律趋于一致。实验鸭群于17日龄分别采用禽流感(H5+H9)双价灭活疫苗和单价灭活疫苗(H5N1亚型,Re-6株)进行免疫,免后45日龄~205日龄不同时间点检测Re-6抗体,结果表明,双价疫苗与单价疫苗均可以诱导免疫鸭产生高水平抗体,而且两种疫苗的消长规律相似。此外,45日龄二免Re-6株疫苗的免疫程序要优于70日龄二免的免疫程序。本研究评估Re-6疫苗的防控效果,为家禽H5亚型禽流感免疫防制提供了实验依据。 相似文献
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为分析蛋鸡免疫后卵黄抗体与血清抗体的相关性,试验采集经H5、H9亚型禽流感和新城疫疫苗免疫的黔东南小香鸡、乌蒙乌骨鸡、威宁鸡血清样本和卵黄样本,采用血凝抑制试验进行相关免疫抗体检测。结果:3个地方品种鸡的血清样本和卵黄样本中均可检测出H5、H9亚型禽流感和新城疫免疫抗体,且几何平均效价均大于24以上,达到免疫合格标准,不同地方品种鸡群间差异不显著(P>0.05);免疫后30d,卵黄样本免疫抗体几何平均效价低于血清样本,但差异不显著(P>0.05);免疫后60d,卵黄样本免疫抗体几何平均效价低于血清样本,差异显著(P<0.05)。结果表明:卵黄抗体与血清抗体呈正相关性,卵黄抗体几何平均效价均低于血清抗体。在临床上可用卵黄抗体替代血清抗体进行H5、H9亚型禽流感和新城疫疫苗免疫效果的评价,但应选择在免疫后30d以内。 相似文献
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《湖南畜牧兽医》2017,(5)
为了更好地评价禽流感疫苗免疫效果,有效预防高致病性禽流感的发生,选用两种重组禽流感病毒H5亚型疫苗(Re-6株、Re-6株+Re-8株)对14日龄雏鸡开展免疫效果的比较试验,结果表明:从免疫抗体水平来看,免疫Re-6株疫苗的A组鸡群在首免后90d抗体水平维持在7log2以上,之后逐渐下降;免疫Re-6株+Re-8株疫苗的B、C组鸡群在首免后28d达到高峰,随之下降,当C组在56日龄加强免疫后,至180d抗体水平仍维持在7.6log2以上。从群体免疫抗体合格率来看,A组免疫合格率至180d低于70%标准,B、C组免疫合格率一直保持70%以上,但C组比B组免疫合格率更高。H5亚型疫苗(Re-6株、Re-6株+Re-8株)均能产生较好的免疫效果,但(Re-6株+Re-8株)疫苗的有效保护期更长,尤其是加强免疫之后,免疫保护率更高。因此建议家禽免疫H5亚型(Re-6株+Re-8株)疫苗,蛋鸡适当加强免疫,从而达到有效预防禽流感的目的。 相似文献
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为了解H5亚型禽流感Re-4毒株疫苗免疫效果,采用血凝-血凝抑制试验(HA-HI)方法对16个县区102个规模场/散养户送检的1621份鸡血清,进行H5亚型禽流感Re-4毒株免疫抗体检测。结果:Re-4毒株免疫血清抗体合格率为72.9%(抗体滴度≥5log2),Re-4毒株免疫抗体合格率高于50%的蛋鸡场户占80.4%,免疫抗体滴度≥7log2的血清份数占合格数的76.2%;发生过H5亚型禽流感疫情和疑似H5亚型禽流感疫情地区的17个养鸡场户,鸡群抗体滴度≥7log2的血清比例占到免疫合格数90%以上。 相似文献
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《中国动物保健》2017,(11)
为监测重组禽流感病毒(H5+H7)二价灭活疫苗(H5N1 Re-8株+H7N9 H7-Re1株)在樱桃谷肉鸭免疫效果,于2017年8~9月,对5个樱桃谷肉鸭养殖场开展了疫苗免疫与抗体检测试验。监测结果表明,35日龄时,有4个场的H5N1 Re-8禽流感亚型疫苗的平均抗体滴度高于4log2,3个场的抗体阳性率高于70%;H7N9禽流感亚型疫苗免疫后5个场的平均抗体滴度均高于4log2,抗体阳性率均高于70%。两个疫苗批次间免疫效果差异不显著(P0.05)。但生长前期禽流感H7N9亚型存在母源抗体空白期;生长中期,禽流感H5N1亚型存在抗体低谷阶段。均存在一定程度AIV感染风险。建议进一步加强疫苗应用监测与免疫程序研究,提醒养殖场户加强生物安全防控,防止疫病发生。需要进一步加强疫苗应用监测与技术指导,提醒养殖户加强生物安全防控,防止疫病发生。 相似文献
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在每年春秋两季的重大动物疫病免疫抗体监测中,我们发现,少部分蛋鸡场的商品蛋鸡一个饲养周期只注射过2次禽流感(H5+H9)二价灭活疫苗,但在商品蛋鸡淘汰时(540日龄左右)采血检测禽流感H5亚型和H9亚型病毒免疫抗体效价,抗体合格率(≥5log2)还在90%以上.目前商品蛋鸡场疫苗防疫种类繁多,如果单用禽流感H5、H9单价灭活疫苗免疫商品蛋鸡,一个饲养周期禽流感疫苗就得注射6~8针.对此,我们用禽流感(H5+H9)二价灭活疫苗分别对两组商品蛋鸡1次性免疫和2次性免疫注射后,定期采血进行HI抗体效价跟踪检测;并对只做2次禽流感(H5+H9)二价灭活疫苗的一个商品蛋鸡场的三批蛋鸡作了禽流感免疫抗体效价和禽流感病毒抗原快速检测的调查.旨在探索一种简便、安全有效的蛋鸡禽流感的预防免疫程序. 相似文献
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禽流感油乳剂灭活疫苗的研究 总被引:33,自引:3,他引:33
将6种不同亚型的禽流感病毒(AIVH2N9、H3N8、H5N1、H5N2、H7N1、H9N2)分别接种鸡胚,收获尿囊液,经甲醛灭活,以矿物油为佐剂制成油乳剂灭活疫苗。疫苗接种4和8周龄SPF鸡,注苗后均无不良反应。每种亚型疫苗免疫后14天和21天攻毒保护率均达90%-100%。分别用H5N1和H9N2亚型灭活疫苗免疫8周龄SPF鸡、25和28周龄健康商品蛋鸡,免疫后7天产生免疫力,14天保护率达100%,21天后抗体达高峰,仔鸡接苗后最高血凝抑制(HI)几何平均滴度(GMT)为7.3-8.0log2,蛋鸡为8.0-10.5log2。免疫后180天,抗体效价不低于6.5log2。免疫后180天分别以AIV攻击,H5亚型疫苗组,用强毒攻击无一发病和死亡,对照鸡全部发病死亡;H9亚型疫苗组,对照鸡在攻毒后72小时停产,免疫鸡无一发病且产蛋正常,对同源攻毒的保护率达100%。 相似文献
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本研究采用AGP、HI等试验方法,对经H9亚型禽流感油乳剂灭活苗免疫、免疫后攻毒以及经H9N2活毒人工感染后的SPF鸡抗体产生、消长规律进行了测定,结果表明人工感染SPF鸡和免疫鸡一周后,AGP的检出率即可达到100%;H9亚型禽流感油乳剂灭活苗自免疫后一周内即可产生HI抗体,21-28天达到高峰,并能对相同亚型病毒感染引发良好的免疫反应。 相似文献
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免疫剂量和母源抗体对禽流感重组鸡痘病毒活载体疫苗免疫效力的影响 总被引:4,自引:0,他引:4
利用表达 H 5亚型禽流感病毒 (AIV)血凝素基因的重组鸡痘病毒 (r FPV- HA)以不同剂量免疫 1日龄 SPF鸡、有或无母源抗体 (FPV、AIV H5)的商品鸡 ,并于免疫后 2 1d利用同亚型 AIV通过肌肉注射进行致死性攻击 ,通过检测免疫后 HI抗体应答、比较攻毒后发病率和死亡率评价免疫剂量和母源抗体对 r FPV- HA免疫效力的影响。结果发现 ,免疫后 2 1d,15 %~ 2 0 %的 SPF鸡和无母源抗体商品鸡可检出 HI抗体 ,而含母源抗体商品鸡检测不到 HI抗体。利用H5亚型 AIV致死性攻击后 ,10 3~ 10 6 PFU的 r FPV- HA可保护 95 %~ 10 0 %的 SPF鸡和无母源抗体商品鸡抵御强毒攻击 ,使之免于发病和死亡 ;而不同剂量 r FPV- HA接种的含母源抗体商品鸡有 80 %~ 90 %发病和死亡。结果表明 ,在较宽的免疫剂量范围内 ,r FPV- HA对 SPF鸡和无母源抗体商品鸡可提供良好的保护 ,显示出一定的应用前景 ;母源抗体影响 r FPV- HA诱导的免疫应答 ,且提高免疫剂量亦不能克服其干扰作用 ,这提示在实际应用中需优化免疫程序 ,避免母源抗体干扰。 相似文献
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Effect of route of administration on the efficacy of a recombinant fowlpox virus against H5N2 avian influenza. 总被引:6,自引:0,他引:6
A recombinant fowlpox vaccine virus containing the H5 hemagglutinin gene of avian influenza virus was administered to susceptible chickens via wing-web puncture, eye drop, instillation into the nares, and drinking water. Even though there was a negligible hemagglutination-inhibition (HI) serologic response, all 10 chickens vaccinated by wing-web puncture remained without obvious signs of disease and survived challenge with a highly pathogenic strain of H5N2 avian influenza virus. All unvaccinated chickens and those vaccinated by nasal and drinking-water routes died following challenge. Eight of 10 chickens vaccinated with the recombinant by eyedrop died. All vaccinates were negative on the agar gel precipitin (AGP) test, and only one chicken had a positive HI titer before challenge. All chickens that survived challenge had high levels of HI antibody and were positive on the AGP test, indicating that they were infected by the challenge virus. 相似文献
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Protection of chickens against highly pathogenic avian influenza virus (H5N2) by recombinant fowlpox viruses. 总被引:19,自引:0,他引:19
Two recombinant fowlpox viruses containing the avian influenza H5 hemaglutinin (HA) gene were evaluated for their ability to protect chickens against challenge with a highly pathogenic isolate of avian influenza virus (H5N2). Susceptible chickens were vaccinated with the parent fowlpox vaccine virus or recombinant viruses either by wing-web puncture or comb scarification. Following challenge 4 weeks later with highly pathogenic avian influenza virus, all birds vaccinated by the wing-web method were protected by both recombinants, while 50% and 70% mortality occurred in the two groups of birds vaccinated by comb scarification. Birds vaccinated with the unaltered parent fowlpox vaccine virus or unvaccinated controls experienced 90% and 100% mortality, respectively, following challenge. Hemagglutination-inhibition (HI) antibody levels were low, and agar-gel precipitin results were negative before challenge. Very high HI titers and positive precipitating antibody responses were observed in all survivors following challenge. 相似文献
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用重组禽流感灭活苗接种10日龄、14日龄和21日龄的SPF鸡,接种后HI抗体效价无显著差异。将H5N1和H5N2疫苗分别接种21日龄SPF鸡,结果表明,H5N1和H5N2均能刺激SPF鸡产生较高的HI抗体;分别接种三黄鸡,接种后21 d,H5N1能刺激三黄鸡产生较高的HI抗体;而H5N2不能刺激三黄鸡产生合格的HI抗体,与SPF鸡免疫组相比差异显著。经过二次接种,HI抗体平均为8.9 log2,与SPF鸡组接种后42 d的各组相比差异不显著,而与一免后21 d的各组HI抗体效价相比差异显著。表明应用禽流感灭活苗对三黄鸡免疫接种,必须进行二免方可达到理想免疫效果,而应用重组禽流感灭活苗对三黄鸡进行免疫接种,一次免疫即可获得较高的HI抗体效价。 相似文献
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H9亚型禽流感油乳剂灭活苗免疫产生期内T淋巴细胞表型亚类的检测与研究 总被引:2,自引:0,他引:2
采用免疫荧光法、使用流式细胞检测仪对经H9亚型禽流感病毒人工感染SPF鸡、H9亚型禽流感油乳剂灭活苗免疫SPF鸡以及经免疫后使用H9亚型禽流感病毒攻毒后的SPF鸡外周血、脾脏、胸腺中T细胞表型亚类(CD4+、CD8+、TCR1+)的变化规律进行了监测,结果表明,H9亚型禽流感油乳剂灭活苗免疫后抗原的缓慢释放可在一定程度上激发机体的细胞免疫应答,使免疫活性T淋巴细胞得到活化,免疫后鸡体外周血中CD4+、CD8+和TCR1+T细胞的数量呈现出一明显升高的过程;同时,人工感染免疫鸡后,脾脏和胸腺TCR1+T细胞的数量上升,外周血CD4+、CD8+和TCR1+T细胞的数量少量降低或维持不变,随后短期即恢复正常;而人工感染SPF对照鸡后,外周血CD4+、CD8+和TCR1+T细胞的数量呈现下降趋势. 相似文献
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Abdelfattah H. Eladl Hamed R. Hamed Mostafa R. Khalil 《Veterinary research communications》2014,38(3):237-247
The consequence of cryptosporidiosis on the immune response of vaccinated chickens against Newcastle disease and/or avian influenza was studied by using 240, 1 day old, male, white Hy-Line chicks and divided into 8 groups and subgroups. Each group or subgroup was consisting of 30 chicks (15?×?2 replicates). The first and second groups were kept as unvaccinated control, G1uninfected and G2 infected. G3, G4 and G5 contained 2 subgroups A&B (G3A, G3B, G4A, G4B, G5A and G5B). Chicks of subgroup A were vaccinated only while chicks of subgroup B were infected and vaccinated. These chicks were orally inoculated with 5?×?105 oocysts of Cryptosporidium baileyi (C. baileyi) at 2 days of age. Chickens were vaccinated intraocular with live Newcastle disease (ND) vaccine (Hitchner on day 7th and LaSota on day 17th of chicken life) (G3) or vaccinated by subcutaneous route with Volvac®- H5N2- AI vaccine on day 10 of chicken life (G4). Last group (G5) was infected similarly and vaccinated with ND and AI vaccines with the same day, dose and route of vaccination for each one. Random blood samples were collected for 3 weeks post-vaccination for investigation of humoral immune response against Newcastle and/or avian influenza vaccines by the haemagglutination inhibition (HI) test. The results showed that H5N2 vaccine at day 10 of chicken life is effective in chickens indicated by the geometric mean of HI titer against AI virus. The findings of this study showed that the infection with Cryptosporidia in the broiler chicken has a depressive effect on the immune status of the birds vaccinated against ND and/or AI vaccination. Moreover, the obtained protection rates against challenge with virulent ND virus observed to be parallel to the results of HI- test. Also, by using 2 different antigens (one commercial and field prepared antigen) to avian influenza virus, lower Geometric mean (GM) HI titer were appeared in infected and vaccinated group than vaccinated group only. A study of the relative lymphoid organs weight such as bursa of Fabricius from the experimental chicks indicated that those organs were comparable between the groups infected-vaccinated and vaccinated only. Non significant variations in final live weight between uninfected control and infected groups were indicated. Also, H5N2-AI vaccination at 10 days old did not affect the final live weight. ND and/or AI Vaccination could not be a substitute to application of good hygienic measures and fecal examination of the birds especially for protozoal diseases such as cryptosporidiosis. It could be concluded that cryptosporidiosis could be one cause of ND and/or AI vaccination failure in poultry farms. 相似文献
20.
禽流感油乳剂灭活疫苗的研制 总被引:18,自引:1,他引:17
以禽流感病毒(AIV)H5N4株,H7N3株为抗原,分别研制了H5N4、H7N3油乳剂灭活疫苗,并对其物理性状、安全性、免疫效力、保存期及抗体消长规律进行了检测。结果表明,3种抗原含量不同的H5N4疫苗在免疫后3周-9个月对AIV-H5N4攻击均获8/8保护,H7N3疫苗在免疫后3周与3个月时对AIV-H5N4攻击则分别保护6/8与3/7,疫苗4℃保存15个月,其免疫效力没有下降。 相似文献