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101.
QU Su-jie SHI Kai-chuang SU Yan-qiong HU Jie MO Sheng-lan ZHANG Bu-xian LI Jun ZOU Lian-bin 《中国畜牧兽医》2015,42(12):3119-3125
To investigate genetic variation of avian infectious bronchitis virus (IBV) in Guangxi province,one strain of IBV was isolated from chicken.Two pairs of primers for amplifying the N and M genes of IBV were designed according to the sequences in GenBank.The N and M genes of the strain were amplified by RT-PCR,and they were proved to be the N and M genes of IBV by cloning,sequencing and compared with reference IBV strains published in GenBank.The results showed that the N gene from the IBV isolate consisted of 1 230 bp,coding 409 amino acids.The M gene from the IBV isolate consisted of 678 bp,coding 225 amino acids.The sequence analysis of N gene showed that it shared 87.2% to 93.3% nucleotide homologies and 90.0% to 94.4% deduced amino acid sequence homologies with IBV strains from GenBank.The M gene sequence analysis showed that it shared 83.6% to 91.0% nucleotide homologies and 82.7% to 92.9% deduced amino acid sequence homologies.The phylogenetic tree analysis showed that it was closely related to BJ and LX4 strains,and were clustered into one group;But with the distant relatives from other strains of IBV.These results suggested that the isolate was a new variant of IBV. 相似文献
102.
ZHOU Yu-zhao MA Zhi-liang SUN Ting-ting YANG Jie ZHANG Xiao-miao CHAI Jun ZHANG Na-na ZHANG Yi-fang 《中国畜牧兽医》2015,42(11):2880-2887
The present study was designed to construct recombinant plasmids,which could express porcine reproductive and respiratory syndrome virus (PRRSV) ORF5 gene.RNA was extracted from spleen and lung samples of the suspected pigs which were infected with PRRSV.According to PRRSV ORF5 gene,a pair of primers was designed for RT-PCR amplification.The ORF5 target gene was cloned into pMD19-T vector and then the recombinant pMD19-ORF5 was achieved.According to the sequencing results and the characteristics of expression vectors,a pair of primers with NcoⅠand XbaⅠenzyme cleavage sites was designed.Target fragment dORF5 was amplified and then connected to pProEXHTb and pNZ8149 vectors,respectively.And recombinant HTb-dORF5/DE3 and pNZ8149-dORF5/NZ3900 was induced by IPTG and Nisin,respectively,and analyzed by SDS-PAGE and Western blotting.Recombinant HTb-dORF5/DE3 induced by 1.5 mmol/L IPTG was expressed in the highest quantity.There were specific band at about 22 ku with reactionogenicity when it was tested by SDS-PAGE and Western blotting.Recombinant pNZ8149-dORF5/NZ3900 induced by 20 ng/mL Nisin was expressed in the highest quantity.There were specific band at about 19 ku with reactionogenicity when it was tested by SDS-PAGE and Western blotting.The IFA result showed specific green fluorescence.This study successfully constructed recombinant plasmids HTb-dORF5 and pNZ8149-dORF5 and expressed,the result laid a solid foundation for further development of PRRS vaccines. 相似文献
103.
104.
从洛江区临床发病鸭分离到2株病毒,2株分离病毒能够致死鸡胚,能被Ⅰ型鸭病毒性肝炎标准强毒高免血清特异性中和。分离毒株在鸡胚上传代培养,并测定ELD50分别为10-6.32/0.2 m L、10-5.49/0.2 m L;经动物回归试验,对1日龄雏番鸭的致死率分别为80%和70%,雏番鸭出现明显的角弓反张姿态,剖检可见肝脏出血斑、出血点,为鸭病毒性肝炎的典型症状,表明分离到的病毒为Ⅰ型鸭病毒性肝炎病毒(DHV-I)。 相似文献
105.
9种中药成分对猪传染性胃肠炎病毒体外增殖的抑制作用 总被引:1,自引:0,他引:1
运用MTT法结合细胞病变方法测定黄芩苷、穿心莲内酯、大黄素、大黄酸、芦荟大黄素、大黄素甲醚、苦参碱、氧化苦参碱和苦马豆素9种中药成分对猪传染性胃肠炎病毒(TGEV)在ST细胞上增殖的抑制作用,实时荧光定量PCR(Real-time PCR)进一步检测黄芩苷对TGEV在ST细胞上增殖的抑制作用。结果显示,9种中药成分在体外对TGEV在ST细胞上的增殖均有一定的抑制作用,其中黄芩苷对TGEV的生物合成、吸附保护和直接灭活作用的抑制率分别为58.23%、88.12%和100.00%;Real-time PCR检测黄芩苷3种给药方式均能在转录水平显著降低TGEV mRNA的相对表达量,与病毒对照组相比差异极显著(P0.01)。结果表明,9种中药成分在体外对TGEV在ST细胞上的增殖均有一定的抑制作用,以黄芩苷作用最好。 相似文献
106.
应用非洲绿猴肾细胞(Vero)从山东省诸城市疑似犬瘟热(canine distemper,CD)感染貉的肝脏、脾脏、肺脏等组织病料的研磨上清液中分离出1株病毒。分离株经Vero细胞传至第4代出现典型的细胞病变效应(CPE),经毒力测定、血清学、RT-PCR检测及测序、回归动物试验证明为犬瘟热病毒(Canine distemper virus,CDV),命名为CDV诸城分离株(CDV-ZC)。采用RT-PCR方法分段克隆分离株的全基因序列并测序,测序成功的各序列依次拼接得到全基因序列并进行序列比对。结果表明,CDV-ZC株全基因(KJ994343)与标准美洲型犬瘟热强毒株A75/17核苷酸同源性高达96.5%,而与疫苗株Onderstepoort、CDV3等亲缘关系较远,同源性为91.6%~92.0%。血凝素(H)基因序列分析表明,CDV-ZC株与国内野毒株LN(13)2、GP株等以及日本野毒株UENO、HAMA等共同归属于Asia-1型,在H蛋白信号淋巴细胞激活因子(SLAM)受体结合区即542~544位增加了1个潜在N-连接糖基化位点(N-X-S/T)。致病性强毒株CDV-ZC的成功分离及全基因序列测定加深了我们对当前中国CDV流行株遗传变异情况的了解,为CD的有效预防、诊断及控制提供理论依据。 相似文献
107.
Shengtao FAN Tiecheng WANG Xiaolong GAO Ying YING Xue LI Yongcheng LI Yuanguo LI Jinzhu MA Heting SUN Dong CHU Yu XU Songtao YANG Qihan LI Yuwei GAO Xianzhu XIA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(9):1143-1149
Newcastle disease virus (NDV) causes a highly contagious viral disease in poultry and
wild birds, and it can cause significant economic loss worldwide. Eight viral strains were
isolated by inoculating embryonated chicken eggs from the Poyang Lake region of China with
swab samples. All eight of the NDV isolates were identified as class I genotype 3 strains,
but they diverged notablely from class II viruses. Further analysis revealed that all
eight NDV isolates were lentogenic strains containing the
112ERQER↓L117 motif at the F protein cleavage site. The strains
were highly identical and were more species specific (chicken and waterfowl) than site
specific (Nanchang and Duchang regions). The close phylogenetic proximity of these
isolates indicates that viral transmission may happen between poultry and wild birds. Our
study demonstrates that lentogenic class I NDVs exist in clinically healthy wild waterfowl
and poultry within the Poyang Lake region. Active surveillance of these viruses to
determine their evolution and origin is one of the most realistic strategies for
preventing and controlling NDV outbreaks. 相似文献
108.
Hiroshi ISEKI Michihiro TAKAGI Kenji KAWASHIMA Tomoyuki SHIBAHARA Yoshiko KURODA Hiroshi TSUNEMITSU Makoto YAMAKAWA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2015,77(12):1663-1666
To clarify the pathogenicity of Japanese type 1 porcine reproductive and respiratory
syndrome virus (PRRSV) isolate in experimentally infected pigs, we evaluated clinical
signs and monitored viremia for 21 days post-inoculation (dpi). Lungs were mottled, tanned
and reddish in appearance; had lesions predominantly in the cranial, middle and accessory
lobes; and failed to collapse at 10 dpi. Although microscopic lesions of lungs were
reproduced using the Japanese emerging type 1 PRRSV isolate under experimental conditions,
no significant differences were noted between the challenge and control groups regarding
mean rectal temperature and daily weight gain. These results provide useful insights into
the limited pathogenicity of single infection with the Japanese type 1 PRRSV isolate in
piglets, which differ from findings in reported field cases. 相似文献
109.
为了研究纯化浓缩的猪细小病毒灭活疫苗的免疫效果,应用微滤/超滤管式陶瓷膜分离系统对猪细小病毒细胞收获液进行纯化浓缩,使浓缩液病毒平均含量由10~(4.7)TCID_(50)/mL提高到10~(6.5)TCID_(50)/mL;将纯化浓缩的病毒液经检验合格后,进行甲醛灭活,与注射用矿物白油佐剂制成油包水灭活疫苗;按照猪细小病毒灭活疫苗的质量标准,对制备的灭活疫苗进行检验与免疫效果试验。结果显示:纯化浓缩的猪细小病毒液杂蛋白去除率平均达到71.6%左右;制备的三组灭活疫苗检验均合格;免疫至63 d时,免疫猪体内抗猪细小病毒抗体(HI)水平分别为:纯化浓缩的灭活疫苗平均高达9.62 log_2稀释倍数,常规疫苗平均为8.78log_2稀释倍数,差异显著(P0.05)。试验表明:疫苗病毒细胞收获液进行膜纯化技术处理后,免疫效果显著优于未经纯化的常规灭活疫苗。 相似文献
110.
采用日本乙型脑炎病毒单克隆抗体预包被酶标板,将纯化的日本乙型脑炎病毒(JEV)作为检测用抗原,利用包被捕获法建立了用于检测猪乙型脑炎抗体的间接ELISA法。采用建立的ELISA法对50份已知阴性血清样本检测,临界OD450nm值为0.343,ELISA与IFA对200份血清进行平行检测,总符合率为92.9%,与商品化的同类国产试剂盒的符合率为95%。与其他常见的猪病毒阳性血清抗体无交叉反应,2~8℃保存12个月稳定。研制的ELISA抗体检测试剂盒为临床JEV血清抗体检测及其疫苗的免疫效果评价提供了技术手段。 相似文献