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试验从发病鸡场分离获得4株鸡传染性法氏囊病病毒(infectious bursal disease virus,IBDV),分别为河北株(HB)、湖北株(HUB)、山东株(SD)、山西株(SX)。通过特异性引物扩增VP2基因并进行测序,序列分析结果显示,4株病毒中,HUB、SD和SX的七肽区为S-W-S-A-S-G-S(aa 326S-332S),其222(A)、256(I)、294(I)和299(S)位是传染性法氏囊病病毒超强毒株(vvIBDV)的4个特征性氨基酸,确定这3株病毒均为超强毒株;而HB株七肽区为S-W-S-A-R-G-S(aa 326S-332S),其222(P)、256(V)、294(L)和299(N)位氨基酸显示该毒株属于弱毒株。进化树分析结果显示,HUB、SD和SX 3株病毒与2011年中国分离的大部分IBDV毒株亲缘关系较近,同源性在96%以上,同时与经典毒株Cro-Po/00、超强毒株GX和UK661亲缘关系很近;而HB株与减毒疫苗株D78株和B87株的亲缘关系近。本试验结果表明,IBDV目前在中国流行呈混发型,但以超强毒株为主。 相似文献
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The infection model of avian reovirus in chicken was established, which layed the ground for vaccine efficacy test.The 49-day-old chickens were inoculated with 102.0, 103.0, 103.5, 104.5and 105.5 ELD50/0.2 mL of two strains of ARV, T98 and AV2311, respectively, in foot pad inoculation method. Clinical signs were observed ten days and recorded daily. 6 days after inoculation, serum samples were taken. 10 days after inoculation, chickens were sacrificed for necropsy. Serum antibody was detected by ELISA. The results indicated that the morbidity of 105.5and 104.5 ELD50/0.2 mL were 100%, and the foot pads of chicken were swelled severely, which were dark red or purple. Symptoms of AV2311 set was a bit lighter than that of T98 strain. The morbidity of 103.5 ELD50/0.2 mL was 90% and the morbidity of 103.0and 102.0 ELD50/0.2 mL were 80%. The ELISA result indicated that only the serum efficacy of 104.5and 105.5 ELD50/0.2 mL set of two strains of ARV were positive.The experiment proved that the virulence of ARV T98 strain was strong, and had good immunogenicity. The best inoculated dose of ARV T98 strain was 104.0 ELD50/0.2 mL, which provided the important basis for researching the quality standard of chicken viral arthrilis vaccine. 相似文献
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禽流感是由A型流感病毒引起的一种急性呼吸道传染病,家禽、野鸟和部分哺乳动物均可感染.禽流感给中国养殖业造成了巨大的损失,同时,随着病毒的种间传播,人类的生命安全也受到了严重威胁.目前,疫苗免疫仍是防控禽流感最主要的手段,传统的疫苗主要有鸡胚灭活苗和禽流感弱毒疫苗.虽然在过往几次禽流感暴发过程中,传统疫苗发挥了重要作用,但其自身却存在诸多弊端,因此研制新型疫苗来弥补传统疫苗的不足是很有必要的.文章主要对禽流感重组活载体疫苗、基因工程亚单位疫苗、DNA疫苗和病毒样颗粒疫苗等新型疫苗的研究进展进行综述,旨在为禽流感的防控提供参考. 相似文献
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