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将引自国外的传染性法氏囊病(IBD)—2512鸡胚弱毒成功地适应于鸡胚成纤维细胞(CEF)培养物。该病毒增殖对生长液要求不苛刻,并能对CEF培养物呈现规律性的稳定的致细胞病变作用(CPE);经反复传代及回归鸡胚绒毛尿囊膜(CAM)重复性试验,都呈现出IBD病毒规律性变化。经毒价测定、安全实验、效力试验证明,该毒株没有因传代和其他因素而改变其特性,其滴度基本稳定在10~(5.50～5.75)EID50/0.2ml,TCID50/0.1ml为10~(7.83～8.17)。 相似文献
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鸭病毒性肝炎A66弱毒株的安全性及稳定性试验 总被引：1，自引：0，他引：1
DHV－A毒株连续通过鸡胚25代后，已失去对雏鸭的致死性，至60代时已对雏鸭无致病力，用A66鸡胚混合毒50万－200万个半数免疫量（DIMD50）经皮下途径接种1日龄雏鸭，无异常反应。A60、A66鸡胚混合毒的毒价分别为10^7.64CELD50/0.1ml和10^7.36CELD50/0.1ml；对1日龄龄急诊鸭经皮下免疫的半数免疫量分别为10^6.36DIMD50/0.1ml和10^6.16DIMD50/0.1ml.A66鸡胚毒连续回归雏鸭5代，全部健活，剖检亦无肉眼可见病变。 相似文献
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将鸡传染性法氏囊病病毒的鸡胚组织毒或法氏囊组织毒直接在鸡胚成纤维细胞(CEF)上盲传3～13代后。能产生特征性细胞病变效应(CPE)。病毒在含65℃灭能30分钟的犊牛血清的细胞生长液制备的CEF上传代,比在含有56℃灭能的犊牛血清的生长液制备的CEF上传代能早3～5代出现CPE,而得到适应;鸡胚高代毒比鸡胚低代毒更易适应CEF;法氏囊组织毒和鸡胚低代毒对适应CEF的进程没有显著差异。 相似文献
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DHV-A毒株连续通过鸡胚25代后,已失去对雏鸭的致死性;至60代时已对雏鸭无致病力。用A_(66)鸡胚混合毒50万～200万个半数免疫量(DIMD_(50))经皮下途径接种1日龄雏鸭,无异常反应。A_(60)、A_(66)鸡胚混合毒的毒价分别为10~(7·64)CELD_(50)/0.1ml和10~(7·36)CELD_(50)/0.1ml;对1日龄雏鸭经皮下免疫的半数免疫量分别为10~(6·36)DIMD_(50)/0.1ml和10~(6·16)DIMD_(50)/0.1ml.A_(66)鸡胚毒连续回归雏鸭5代,全部健活,剖检亦无肉眼可见病变。 相似文献
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用传染性法氏囊病(IBD)流行强毒株“郑毒”株与保存的强毒J_4株人工感染7日龄和45日龄IBD阴性鸡、非免疫鸡胚及鸡胚成纤维细胞。对7日龄雏鸡,“郑毒”株能引起75%发病,23%死亡;J_4株只造成亚临床感染。对45日龄雏,“郑毒”株经40～60小时能引起100%发病,45%死亡,且肌肉、肾、肠、腺胃、法氏囊严重出血,法氏囊萎缩迅速,接毒后3天和8天的囊/体重比值分别为1.7和0.58;J_4株虽也可引起发病,但症状轻微,10%死亡,接寿后3天法氏囊显著肿胀,囊/体重比值为3.9,是“郑毒”株的2.2倍。两毒株虽能在非免疫鸡胚上增殖,并致其死亡,但“郑毒”株引起的死亡率高于J_4株,且病变更严重。在鸡胚成纤维细胞上盲传3代,两毒株都不出现CPE,表明还不适应于细胞上增殖。对接毒后进行LaSota疫苗免疫的7日龄雏鸡,“郑毒”株能产生更大的免疫抑制。据两毒株在致病力上的差异表明,”郑毒”可能是一株毒力更强的血清Ⅰ型亚型株或变异株. 相似文献
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鹅细小病毒弱毒株选育的研究 总被引：3，自引：0，他引：3
应用番鸭胚成纤维细胞（MDEFC）培育出适应MDEFC增殖并产生细胞病变的鹅细小病毒弱毒疫苗株，同时测定了该弱毒株的部分生物米特性。结果显示：该弱毒株已失去对1日龄雏番鸭的致病性，在雏番鸭体内连续肓传5代，未见毒力反强现象；该弱毒株对MDEFC的TCID50稳定在10^-5-10^-6/0.1ml；1日龄雏番鸭免疫接种后7天攻毒可获100％保护，表明该弱毒株安全、免疫原性良好。 相似文献
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经鸡胚绒毛尿囊膜(CAM)接种、易感鸡接种试验、电镜观察,从安徽地区疑似病鸡的法氏囊组织分离到3株传染性法氏囊病毒。分离株人工感染4周龄鸡,致死率分别为92%、83%、67%。接种9～10SPF鸡胚测得的鸡胚半数致死量(ELD50)分别为10-6.8/0.2mL、10-5.4/0.2mL、10-4.6/0.2mL。应用Nested-PCR分别对3株分离株VP2基因高变区进行克隆测序和序列分析,结果表明:3个分离株与国内外参考超强毒株的核苷酸同源性为97.2%～99.5%,氨基酸同源性为99.3%～100%,VP2高变区核苷酸和推导的氨基酸符合传染性法氏囊病病毒超强毒株特征。 相似文献
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《畜牧兽医学报》2017,(5)
本试验拟研究不同致病性H9N2亚型禽流感病毒诱导SPF鸡、SPF鸡胚和鸡胚成纤维细胞中TLR-7和Mx基因mRNA转录水平的动态变化,为不同致病性H9N2亚型禽流感病毒诱导IFN-Ⅰ产生差异的机制提供依据。150只6周龄SPF鸡随机分为3组,分别静脉接种PBS、105 EID50毒株SD/196和SD/818各0.2mL,分别于接种后的第1、3、5、7和10天每组剖杀8只,收集具有明显病变差异的组织;180枚10日龄SPF鸡胚分别尿囊腔接种PBS、104 EID50的SD/196毒株和SD/818毒株各0.1mL,分别于接种后的第4、8、16、24、32和48小时每组收集胚体10个;鸡胚成纤维细胞分别接种PBS、SD/196和SD/818毒株病毒液(1moi)进行37℃培养,于感染后的第4、8、16、24、32和48小时收集细胞;动态收集的病变组织、胚体和成纤维细胞通过荧光定量PCR测定TLR-7和Mx基因mRNA水平的表达。结果显示,肺、肾、十二指肠和法氏囊为主要病变差异组织,除鸡胚TLR-7的表达外,毒株SD/818大部分时间点诱导主要病变差异组织、鸡胚和成纤维细胞中TLR-7和Mx基因mRNA的表达显著高于毒株SD/196(P0.05)。结果表明不同致病性H9N2亚型禽流感病毒明显诱导了SPF鸡主要病变差异组织、SPF鸡胚和鸡胚成纤维细胞中TLR-7和Mx基因mRNA的表达,且较高致病性毒株SD/818诱导表达量明显高于较低致病性毒株SD/196。 相似文献
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对我国分离的鸽新城疫坪山毒和川沙毒对鸡胚致死性、鸡胚传代毒的血凝价、对健康鸽致病性以及对鸡胚细胞感染性等一些生物学特性进行了研究和比较,结果表明:二毒株接种鸡胚都能使鸡胚致死,川沙毒致死鸡胚时间略早于坪山毒.二毒株都能在鸡胚传代,鸡胚毒血凝价平均值约2~■.毒株感染鸡胚细胞能规律性地对细胞引起病变作用.对健康鸽都具有致病性,川沙毒致病性指数高于坪山毒,并能引起四周龄肉鸡发病. 相似文献
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传染性法氏囊病超强毒Gx株的致弱研究 总被引：11，自引：2，他引：9
本研究成功将鸡传染性法氏囊病超强毒vvIBDVGx株通过SPF鸡胚的快速培育及鸡胚成纤维细胞传代致弱，揭示了vvIBDV从超强毒力向弱毒力转化过程中，其主要结构蛋白VP2基因核苷酸及推导的氨基酸序列的变化规律。对不同代次细胞毒进行了序列分析。发现细胞毒在第7代以前，VP2基因序列没有改变。与欧洲标准超强毒氨基酸同源性达100%；细胞毒第8代，有个别核苷酸发生了改变。但没有影响氨基酸序列；细胞毒第9代是变化复杂的过渡代；10代毒VP2基因与欧洲标准弱毒Cu-1氨基酸序列同源性达97%；以后的细胞适应毒至20代。其VP2基因序列不再改变。致病性实验表明原代毒对4周龄SPF鸡致死率为64%。细胞毒第5代的致死率为60%，而20代毒对鸡无致病性。在鸡体内连续传代6代不返强。 相似文献
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Changes in VP2 gene during the attenuation of very virulent infectious bursal disease virus strain Gx isolated in China 总被引：6，自引：0，他引：6
Very virulent (vv) infectious bursal disease virus (IBDV) Gx strain with high pathogenicity was attenuated through replication in specific-pathogen-free (SPF) chicken embryos and in chicken embryo fibroblast (CEF) cell cultures. The changes in VP2 nucleotide and the deduced amino acid sequences were obtained during attenuation of vvIBDV in CEF culture. Sequence analysis of selected passages from numbers 0 to 20 in CEFs (designated here Gx to CEF-20) showed that no changes were detectable in the VP2 gene before CEF-7. There were a few changes in the nucleotide sequence of the VP2 gene but no amino acid substitutions at CEF-8. The virus of CEF-9 was an intermediate with some amino acid changes that possibly were related to virulence. CEF-10 virus had become similar to CU-1 strain. The VP2 gene sequence remained the same from CEF-10 to CEF-20. The results of pathogenicity tests showed that the mortalities of Gx, CEF-5, CEF-8, and CEF-9 in 4-wk-old SPF chickens were 64%, 60%, 60%, and 32%, respectively; whereas CEF-10, CEF-15, and CEF-20 were nonpathogenic. Virus neutralization tests with Gx strain showed that the antigenicities are similar from Gx to CEF-20. 相似文献
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【目的】 研究1株传染性法氏囊病病毒（Infectious bursal disease virus,IBDV）广西分离株的毒力特征及其与VP2基因序列特征的关系,为IBDV的流行病学研究和疫病防控提供参考。【方法】 通过PCR、鸡胚传代培养、DF-1细胞的适应培养及琼脂扩散试验等方法分离鉴定病毒,并扩增其VP2基因,利用Mega 7.0、MegAlign软件将其与其他不同毒力IBDV毒株进行核苷酸及氨基酸序列比对分析,并进行SPF鸡致病性试验,用实时荧光定量PCR方法测定IBDV拷贝数变化情况。【结果】 成功分离到1株IBDV毒株,命名为GX20210126株。该毒株接种SPF鸡胚可导致鸡胚出现出血、矮化和肝脏发黄、出血及针尖状坏死;且GX20210126对DF-1具有良好的细胞适应性,可引起显著细胞病变。琼脂扩散试验显示,该毒株具有良好的抗原性,病毒液能与IBDV阳性血清之间形成白色沉淀线。VP2基因进化分析显示GX20210126株与国际标准超强毒株在同一个大的分支上,氨基酸序列相似性在86.8%~99.6%之间,其中与UK661株相似性最高,为99.6%,仅有2处氨基酸位点发生改变,即D279N和I272T。以EID50为10-3.8/0.1 mL,0.5 mL/只的剂量点眼、滴鼻接种8日龄SPF鸡,攻毒后鸡出现羽毛蓬松、精神萎靡、拉白绿色水样粪便等临床症状,剖检可见肌肉、肝脏出血,肾脏尿酸盐沉积,法氏囊萎缩,IBDV拷贝数在感染后第5天达到峰值。【结论】 IBDV广西流行株GX20210126具有超强毒株基因序列特征,人工感染鸡群可导致IBDV典型临床症状和病理变化。 相似文献
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The pathogenicity of serotype 2 OH strain of infectious bursal disease virus (IBDV) to specific-pathogen-free (SPF) chicken embryos and 2-wk-old SPF chickens and turkey poults was investigated. The virus was pathogenic for chicken embryos after five passages as evidenced by pathologic changes in inoculated embryos. The embryo-adapted virus was not pathogenic for 2-wk-old SPF chickens and turkey poults as indicated by lack of clinical signs, gross or microscopic lesions in the bursa of Fabricius of inoculated birds. Bursa-to-body-weight ratios of the inoculated chickens and turkey poults were not significantly different from those of uninoculated controls. Virus-neutralizing antibodies to serotype 2 IBDV were detected in inoculated chickens and turkeys. Results of this study indicated that the embryo-adapted serotype 2 OH IBDV isolate that is pathogenic for chicken embryos is infectious but not pathogenic in chickens and turkeys. 相似文献
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ZHANG Zhen-hua LI Lin JING Xiao-dong ZHANG Jian-wei SHEN Jia SHI Ai-hua ZHENG Xiao-lan HUANG Feng-jun JIANG Bei-yu 《中国畜牧兽医》2015,42(12):3338-3343
One-day-old moderate maternal antibody Jinghong chickens and SPF chickens were vaccinated with infectious bursal disease (IBD) immune complex (IC) vaccine and BX strain live vaccine,respectively,pathological changes of bursa of fabricius in chickens were observed at the 9th day after immunization.On the 28th day after immunization,blood samples were taken and the IBDV neutralizing antibody were tested,meanwhile experimental chickens were challenged with high virulent IBDV,the protective rates of experimental groups were calculated.The results showed that at the 9th day after immunization,the bursa of fabricius in SPF and Jinghong chickens were normal in IC vaccine group,however atrophic changes of bursa of fabricius in BX strain live vaccine group were shown.At the 28th day after immunization,the IBDV neutralizing antibody of IC vaccine group and BX strain live vaccine group in SPF and Jinghong chickens were 9.2log2,8.5log2,7.2log2 and 4.4log2,respectively,while 100% protection rates were provided.The results provided that IC vaccine had better immunity effect on one-day-old moderate maternal antibody chicken,high levels of neutralizing antibodies against IBDV were produced and protection rates were 100%. 相似文献
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将鸡传染性法氏囊病免疫复合物疫苗和BX株活疫苗分别免疫1日龄中等母源抗体水平京红雏鸡,同时免疫1日龄SPF雏鸡作对照,免疫后第9天观察法氏囊病变,免疫后第28天采血测定IBDV中和抗体,并用强毒攻击,计算各组疫苗保护率。结果显示,免疫后第9天,免疫复合物疫苗组SPF雏鸡和京红雏鸡法氏囊均正常,BX株活疫苗组SPF雏鸡法氏囊出现了萎缩病变;免疫后第28天,对照SPF雏鸡和京红雏鸡的免疫复合物疫苗组、BX活疫苗组IBDV中和抗体效价分别为9.2log2、8.5log2和 7.2log2、4.4log2,攻毒保护率均为100%。试验结果表明免疫复合物疫苗免疫1日龄中等水平母源抗体雏鸡效果很好,能产生较高的中和抗体,攻毒保护率能达到100%。 相似文献
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Kelemen M Forgách K Iván J Palya V Süveges T Tóth B Mészáros J 《Acta veterinaria Hungarica》2000,48(4):443-454
The appearance of very virulent strains of infectious bursal disease (IBD) virus at the end of the 1980s made it necessary to develop more effective immunization procedures. To facilitate this, the immunogenicity and the immunosuppressive effect of a mild (G-87), an intermediate (LIBD) and an intermediate-plus (IBDV 2512) IBDV strain were tested after the in ovo inoculation of 18-day-old SPF and broiler chicken embryos. It was established that no noteworthy difference existed between the immunized and the control embryos in hatching rate and hatching weight. The higher the virulence of the vaccine virus strain, the more severe damage it caused to the lymphocytes of the bursa of Fabricius. In SPF chickens, the haemagglutination inhibition (HI) titres induced by a Newcastle disease (ND) vaccine administered at day old decreased in inverse ratio to the virulence of the IBD vaccine strain, while in broiler chickens this was not observed. Despite the decrease of the HI titre, the level of protection did not decline, or did so only after the use of the 'hot' strain. SPF chickens immunized in ovo with a complex vaccine prepared from strain IBDV 2512 and IBD antibody showed the same protection against Newcastle disease as the broilers. In broiler chicken embryos immunized in ovo, only strain IBDV 2512 induced antibody production, and such chickens were protected against IBD at 3 weeks of age. The complex vaccine administered in ovo has been used successfully at farm hatcheries as well. 相似文献
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