The specificity of the nucleic acid probe was very strict . lt reacted positively with iltv dna only and it react negatively with the nuleic acid of ndv , bv and ibdv . the sensitivity of this kind of probe is very high . ilt could even detect 20pg ' s iltv dna 结果表明：该种核酸探针具有高度的特异性，它仅与iltv的dna呈现阳性反应，而与新城疫病毒、传染性法氏囊病病毒和传染性支气管炎病毒的核酸等均呈阴性反应。该种探针具有高度的敏感性，能够检测到20pg的iltv的dna 。
The chickens and chicken embryos were inoculated with variant serotype isolate e of infectious bursal disease virus using cloacal , nosal routes or via the allantoic cavity route , and the histopathological features of the bursa of fabricius of the ibdv _ infected chickens at various intervals of time were systematically investigated 本试验全面而系统地观察了传染性法氏囊病病毒变异e株，通过泄殖腔、鼻腔和尿囊腔接种雏鸡和鸡胚后不同时间法氏囊的组织形态学变化。
These results showed that the three isolates were infectious bursal disease virus . the full - length cdna of the genomic segment a of two viruses , one virulent field strain ibdv zj2000 and one attenuated strains ibdv jd1 , were amplified in a single step procedure by long - accurate reverse - transcription polymerase chain reaction ( la - pcr ) , cloned into pgem - t easy vector , and sequenced 分别以传染性法氏囊病病毒zj2000株(野毒株)和jd1株(弱毒株)基因组dsrna为模板，采用long - accuratert - pcr ( la - pcr )一步法扩增并克隆了两株病毒的基因组a节段全长cdna 。
The results also indicated that the virulence of the most ibdv field collected in recent years was between the typical very virulent and standard virulent strains . a very virulent strain gx8 / 99 of ibdv was studied for its mortality in spf chickens and commercial egg - type chickens at different age inoculated with bursal suspension of 20 - 2000 eld50 in repeated experiments 选择致病性最强的来自广西的gx8 99株，在对法氏囊悬液中病毒用鸡胚半数致死量( eld _ ( 50 ) )定量测定后，在不同年龄的spf鸡和商品代蛋用型坞多次重复地比较研究了该毒株的致病性。
The high specificity of dot - elisa was proved by the specific blocking test and the cross - reaction te st in which the diagnostic diaphragm did n ' t react with the positive serum against ibdv , ibv , eds - 76 , pox , ibv , iltv , salmonellosis jc . both the test within batch and the test among batches proved the method or the diagnostic diaphragm was stable . stored at 4c for at least 6 months , the diagnostic diaphragm ' s sensitivity and specificity did n ' t change 阻断试验和交叉试验表明快诊膜具有良好的特异性：不与马立克、法氏囊、鸡痘、鸡传支、鸡传喉、鸡减蛋综合症、鸡传鼻、鸡沙门氏菌等阳性血清反应。批内和批间重复性试验表明该法重复性良好。诊断膜片4至少可保存6个月，其特异性、灵敏性不变。
Three ibdv strains , designated as zj2000 , zj991 and zj992 , were isolated from bursa of fabricius of the sick chicken flocks in hangzhou , shenzhou , and ningbo of zhejiang province . the isolates could react with ibdv positive reference serum in the agar immune - diffusion test and caused 30 - 100 % mortality when passaged in chicken embryos . chickens inoculated with these isolates exhibited clinical and pathological signs typical of infectious bursal disease 从浙江省杭州、嵊州，宁波等地暴发疑似传染性法氏囊病的鸡群中采集法氏囊病料(编号分别为zj2000 、 zj991 、 zj992 ) ，分离病毒，经琼脂免疫扩散试验、动物回归试验、鸡胚回归试验和电镜观察等证实所分离的3株野毒是传染性法氏囊病病毒。
Sequence and phylogenetic analysis of segement a of chinese infectious bursal disease virus ( ibdv ) hb - bp strain isolated from hebei province was studied in this thesis . the experiments as below were included : double - strand rna of viral genome was purified by licl gradient precipitation , 48 hours after bursa was harvested from chicken which had been inoculated with hb - bp strain . referred to the published sequence two primers were designed and synthesized 给4周龄spf雏鸡人工接种鸡传染性法氏囊病病毒hb - bp毒株， 48小时后采取法氏囊，用双licl分级沉淀法提纯全长基因组dsrna ，设计一对引物，通过rt - pcr方法进行了体外扩增，获得hb株a节段基因全长cdna 。
Spf chickens with 21 - day - old were infected subcutaneously with oil - emulsion vaccine of ibdv of germinal or cellcular and injected intramuscularly with different dosages bursin which gain through ultrafilter . lt is proved that bursin of chickens and ducks can both shorten the time of antibody induced against ibdv , raise the level of serum antibody . they make chickens obtaining strong immunocompetente in a short time . agp liters of the group of infecting 0 . 4mlcbs + ibdv of germinal and 0 . 8mlcbs + ibdv of cellcular or 0 . 8mldbs + ibdv of germinal and cellcular are higher than immune control group about 2 liters averagely . the chickens were inoculated with ibdv live vaccine mixed with the different dosages of lyophilized bursin by the eye drop method . the results sugest that cbs or dbs of different dosages can both improve the antibody inducation to different age chickens against ibdv . they may also alleviate the immunological injury of activated virus to bursa of fabricius . and promote the repairation of the lesion . it can be found that bs can raise body weight gain and feed coversion ratio 将超滤获得的法氏囊活性肽分别以不同剂量肌肉注射21日龄spf鸡，同时颈部皮下注射ibd胚毒或细胞毒灭活苗，结果表明：鸡、鸭法氏囊活性肽都能够缩短ibd油苗诱导产生抗体的时间，提高抗体水平，使鸡可以在比较短的时间内获得坚强的免疫。 0 . 4mlcbs胚毒组和0 . 8mlcbs细胞毒组或0 . 8mldbs胚毒和细胞毒组的agp抗体滴度平均比免疫对照组高2个滴度。将法氏囊活性肽与ibd活苗联合免疫鸡，结果表明：不同剂量的cbs和dbs都可以对不同日龄鸡ibd抗体的产生有不同程度的促进作用；还可以减少弱毒对鸡法氏囊组织的损伤，加快其修复。
Northern blot analysis indicated that foreign ibdv vp2 gene was correctly transcripted into mrna . the recombinant protein from tobacco leaves was detected by dot - elisa and western blot using antisera specific for ibdv . the protein ibdv vp2 expressed in tobacco appeared with apparent molecular mass of 52kd 取生长期烟草植株，经pcr检测和southern杂交检测，证明外源基因ibdvvp2成功整合到烟草染色体上； northern杂交分析表明转基因烟草中存在正确转录的ibdvvp2基因的mrna ； dot - elisa和westernblot分析证实转基因烟草中产生了能与ibdv特异性抗血清反应的ibdv抗原蛋白，其大小约为50kd 。
The result shows that a vvibdv strain was obtained , the above work lay a important role for further studying on the molecular biological mechanism of antigenic drift and virulence variation of ibdv , molecular epedimiology , it also provided the basis for recombinant and gene deleted vaccine of ibdv 本实验可以帮助我们进一步探讨ibdv抗原性漂移和毒力变化的分子生物学机制，追溯ibdv的起源，理解病毒的传播方式。同时也为研制开发基因重组疫苗和缺失疫苗打下一定的基础。
