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71.
Wang H Gao Y Gong Y Chen X Liu C Zhou X Blackall PJ Zhang P Yang H 《Veterinary microbiology》2007,119(2-4):231-239
Avibacterium paragallinarum is the causative agent of infectious coryza. The protective antigens of this important pathogen have not yet been clearly identified. In this paper, we applied phage display technique to screen the immunodominant mimotopes of a serovar A strain of A. paragallinarum by using a random 12-peptide library, and evaluated the immunogenicity in chickens of the selected mimotope. Polyclonal antibody directed against A. paragallinarum strain 0083 (serovar A) was used as the target antibody and phage clones binding to this target were screened from the 12-mer random peptide library. More than 50% of the phage clones selected in the third round carried the consensus peptide motif sequence A-DP(M)L. The phage clones containing the peptide motif reacted with the target antibody and this interaction could be blocked, in a dose-dependent manner, by A. paragallinarum. One of the peptide sequences, YGLLAVDPLFKP, was selected and the corresponding oligonucleotide sequence was synthesized and then inserted into the expression vector pFliTrx. The recombinant plasmid was transferred into an expression host Escherichia coli GI826 by electroporation, resulting in a recombinant E. coli expressing the peptide on the bacterial surface. Intramuscular injection of the epitope-expressing recombinant bacteria into chickens induced a specific serological response to serovar A. A. paragallinarum. The chickens given the recombinant E. coli showed significant protection against challenge with A. paragallinarum 0083. These results indicated a potential for the use of the mimotope in the development of molecular vaccines for infectious coryza. 相似文献
72.
布鲁氏菌病(简称布病)是一种危害严重的人兽共患病。近几年,随着畜牧业的发展和动物的频繁调运,我国布病防控形势日益严峻。疫苗免疫是我国布病一类地区控制该病的主要方法,但由于现有布病疫苗对人有一定的致病性,导致部分地区免疫实施效果不能有效保障。辽宁省葫芦岛市建昌县通过多年实践,创新了一种经阴道途径免疫S2疫苗的新型布病免疫技术。该技术对羊免疫安全性高、抗体阳转率高,抗体持续期长于经口途径免疫。该免疫技术在辽宁省建昌县和葫芦岛市其他地区推广使用后,取得了较好的免疫保护效果,并有效降低了人间的布病感染率,是我国其他一类地区可参考的一种布病免疫新技术。 相似文献
73.
74.
为建立一种灵敏、准确、快速的山羊痘病毒(GTPV)和小反刍兽疫病毒(PPRV)双重PCR检测方法,根据GenBank上登录的GTPV、PPRV两种病毒的基因序列设计检测引物,在常规PCR基础上,对反应条件及反应体系进行优化,建立了这两种病毒的双重PCR检测方法,并进行了特异性、敏感性检验。结果显示:仅GTPV和PPRV核酸样品扩增出与预期目标相符的目的片段,而其他病原对照均未出现目的条带;GTPV的最低检出量为0.283 ng/μL,PPRV的最低检出量为6.459 ng/μL。结果表明,本研究建立的双重PCR检测方法可一次性同时完成PPRV、GTPV两种病原的检测,且具有较高的特异性和敏感性。本方法的建立为山羊痘和小反刍兽疫的临床诊断、流行病学研究、疫情监测提供了技术支持。 相似文献
75.
Genetic mapping using 1.4M SNP array refined loci for fatty acid composition traits in Chinese Erhualian and Bamaxiang pigs 下载免费PDF全文
J. Zhang Y. Zhang H. Gong L. Cui T. Huang H. Ai J. Ren L. Huang B. Yang 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2017,134(6):472-483
Chinese indigenous pigs display marked genetic and phenotypic differences compared with western commercial pigs. In this study, we tested the association between 660K SNPs and longissimus muscle fatty acid composition traits in Chinese Erhualian (n = 331) and Bamaxiang (n = 315) pigs based on a customized 1.4 million SNP array. We identified a total of 64 significant associations for 20 fatty acid composition traits at the p‐value threshold of 1 × 10?6 among which 42 associations in low linkage disequilibrium (r2 < .2) with previously reported loci were considered novel. We substantially improved the strength and precision of the associations at four previously detected loci near FADS2, ELOVL7, ELOVL6 and FASN genes, facilitating follow‐up candidate gene studies. Moreover, we also identified loci near ABCD2, ACSBG1, ELOVL5, HPGDS, DAGT2, ACAD10 and ACSL1 genes with function relevant to metabolism of fatty acids. In this study, valuable genetic variants and candidate genes associated with fatty acid composition traits were identified in Erhualian and Bamaxiang pigs. Some identified loci could be used to improve pork nutrition in pig breeding practice. Using the SNP array with higher marker density and less ascertainment bias improved QTL detection power and precision in Chinese indigenous pigs. 相似文献
76.
A peptide of foot-and-mouth disease virus serotype Asia1 generating a neutralizing antibody response, and an immunostimulatory peptide 总被引:2,自引:0,他引:2
Wang JL Liu MQ Han J Chen WZ Cong W Cheng G Gao YH Lu YG Chen JL Zuo XP Yan WY Zheng ZX 《Veterinary microbiology》2007,125(3-4):224-231
The epitopes of the capsid of foot-and-mouth disease virus (FMDV) play important roles in the construction of highly immunogenic subunit vaccines. However few epitopes have been found for FMDV serotype Asia1. In this study we screened for epitopes of the VP1 and VP2 proteins of FMDV serotype Asia1 isolate, YNBS/58. Fragments consisting of amino acids 133-163 of VP1 and amino acids 1-33 of VP2 contained epitopes, and both induced lymphoproliferation in guinea pigs. Only the VP1 fragment induced neutralizing antibodies but the VP2 peptide dramatically increased the neutralizing antibody response induced by the VP1 peptide. 相似文献
77.
本文综述了生物技术在改造和提高饲料原料的营养价值(品质、产量、利用率等),培育高生产性能、抗病力强的动物品种,改善和提高动物产品品质和风味等方面的应用研究进展以及营养与基因表达调控的关系。 相似文献
78.
A DNA vaccine (pVAX1-TgADF) encoding Toxoplasma gondii actin depolymerizing factor (ADF) gene was constructed and the immune response and protective efficacy of this vaccine against homologous challenge in BALB/c mice were evaluated. High titers of specific antibody and increases in the percentage of CD4(+) and CD8(+) T lymphocyte cells were observed from BALB/c mice vaccinated with pVAX1-TgADF (P<0.05), when PBS group was used as control. The survival time of BALB/c mice in pVAX1-TgADF group was longer than those in control groups. The numbers of brain cysts in the experimental BALB/c mice immunized with pVAX1-TgADF reduced significantly compared with those in PBS group (P<0.05), and the rate of reduction could reach to around 42.8%. These results suggested that the DNA vaccine pVAX1-TgADF could generate specific humoral and cellular immune responses, prolong survival times, and reduce brain cysts load against T. gondii infection in BALB/c mice. 相似文献
79.
80.
本试验将三七总皂甙(PNS)体外作用于大黄鱼肾细胞,通过活细胞计数和荧光定量PCR检测,初步了解PNS对大黄鱼肾细胞生长及部分免疫相关因子表达的影响。结果显示,40~200μg/mL浓度的PNS对大黄鱼肾细胞生长无明显影响,但浓度达到1 mg/mL以上时,对细胞生长有负面影响;10~1 000μg/mL浓度的PNS对大黄鱼肾细胞Toll样受体5mRNA的表达有一定的上调作用,但对Toll样受体3的表达有一定的下调作用;PNS浓度为10~100μg/mL时对大黄鱼肾细胞碱性磷酸酶的表达无明显影响,但浓度达到1 000μg/mL时对该因子的表达有下调作用;PNS浓度为10μg/mL时对大黄鱼肾细胞溶菌酶的表达无明显影响,但浓度达到100μg/mL以上时对该因子的表达具有一定的下调作用。 相似文献