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1.
布鲁菌引起的布鲁菌病在我国被列为二类动物疫病之首。虽然宿主本身具有复杂的免疫机制,用以抵御病原体,并保持宿主抗性和布鲁菌毒力之间的平衡,但布鲁菌作为一种成功的细胞内病原体,已经进化出多种策略来逃避免疫应答并在宿主内建立持续感染和繁殖。论文将从布鲁菌的毒力因子、布鲁菌在先天性免疫和适应性免疫系统中隐身策略,以及布鲁菌调控并抑制细胞凋亡、布鲁菌微小RNA(mircoRNA)在宿主免疫应答中的研究进展等方面进行综述,为了解布鲁菌病发病机理、开发新型疫苗和治疗布鲁菌病提供参考。  相似文献   

2.
通过分析布鲁菌疫苗株基因序列遗传变异情况,为疫苗的免疫保护力的评价提供理论依据,本研究利用高变量八聚物寡核苷酸指纹技术(HOOF-Prints)对国内主要布鲁菌疫苗-羊种布鲁菌疫苗M5、猪种布鲁菌疫苗S2、牛种布鲁菌疫苗S19、人用布鲁菌疫苗104M进行序列分析,并基于布鲁菌标准参考株采用软件DNAMAN进行系统进化树分析。结果表明4种疫苗株的基因序列均发生了变异,但系统进化树分析显示这些疫苗株与对应的参考株遗传关系仍然最近,同时表明该指纹技术在分子水平上可以用于分析和了解国内主要疫苗的变异情况,为疫苗的免疫效果提供理论依据。  相似文献   

3.
以粗糙型布鲁菌M111株和重组裂解质粒制备出布鲁菌菌壳,利用小鼠模型对布鲁菌菌壳、布鲁菌M111活菌和福尔马林灭活菌的安全性和免疫原性进行比较研究。结果显示,与布鲁菌弱毒菌株M111比较而言,布鲁菌菌壳具有更好的安全性,免疫小鼠后能产生与弱毒菌株相似的血清抗体水平、脾CD3+和CD4+T淋巴细胞反应,甚至产生更高水平的IFN-γ。这些结果表明,布鲁菌菌壳具有与弱毒菌株相似的体液免疫和细胞免疫能力,将来可能作为预防布鲁菌感染的新型候选疫苗,但布鲁菌菌壳疫苗的有效性和特异性免疫机制还有待深入研究。  相似文献   

4.
为研制安全、有效、新型靶向化布鲁菌外膜蛋白疫苗,采用去污剂连续抽提与电洗脱法分离纯化出布鲁菌外膜蛋白,并进行α-D-甘露吡喃异硫氰酸苯酯糖基修饰、佐剂乳化.依据统计学中完全随机实验设计试验,免疫BALB/c小鼠,收集不同时间点血液样品,ELISA法检测血清中IgG和IFN-γ含量.结果显示分离纯化出37.5 kD与47.2 kD的目的蛋白并成功糖基化修饰;纳米颗粒佐剂乳化后的试验用疫苗免疫小鼠,血清IFN-γ水平呈显著升高趋势(P<0.05);抗体水平略显优势,但差异不显著(P>0.05).表明试验用疫苗能激发机体的细胞免疫应答,且产生了免疫记忆.本研究为研制布鲁菌新型靶向化疫苗的研发和推广提供了研究依据.  相似文献   

5.
<正>动物布鲁菌病是一种严重影响牛、羊养殖业的人兽共患传染病,给畜牧业生产和人类健康带来了巨大的危害。在疫情比较严重的地区,通过给易感动物接种布鲁菌病疫苗,是目前防控动物发生布鲁菌病的主要措施之一。在疫苗厂家提供的布鲁菌病疫苗使用说明书中,规定可以通过口服或肌肉注射等方法进行免疫,但是这两种免疫方法在实际的疫苗免疫中的免疫效果以及差异并没有提到。本试验通过口服和肌肉注射两种接种途径对羊进行  相似文献   

6.
本研究利用体内诱导表达抗原技术(IVIAT)来筛选和鉴定羊布鲁菌特异的体内诱导抗原,为筛选新的毒力分子,诊断靶标、疫苗候选抗原和药物靶点提供科学依据。通过收集临床上羊布鲁菌阳性血清,吸附后作为探针,构建羊布鲁菌16M基因组表达文库,进行体内诱导抗原的筛选,同时利用RT-PCR验证筛选得到的基因,对筛选得到的基因进行测序比对及生物信息学分析。结果显示:利用临床上感染布鲁菌的羊阳性血清作为探针,通过体内诱导抗原技术成功地从羊布鲁菌的基因组中筛选得到了14个体内诱导表达的基因。这些基因主要参与布鲁菌的糖代谢、tRNA修饰、离子转运和跨膜运输等生物过程,这些分子有的已经被证实是布鲁菌的药物靶点和毒力分子,有的可能与布鲁菌的毒力和免疫相关,可以作为疫苗候选抗原和诊断标识。体内诱导抗原技术(IVIAT)成功地应用到布鲁菌候选抗原和诊断标识的筛选和鉴定研究中,利用该技术成功获得14个体内诱导基因,这些基因将为布鲁菌疫苗的研制和诊断产品的研发提供候选抗原和诊断标识。  相似文献   

7.
布鲁菌病是重要的人兽共患病,对畜牧业发展和人类健康威胁严重。疫苗免疫仍是目前预防和控制动物布鲁菌病的措施之一,用于羊布鲁菌病防控有多种疫苗,如S19、RB51、Rev.1等,每种疫苗均各有利弊。现今,众多研究者也通过基因工程等技术积极研究DNA疫苗、基因缺失疫苗、亚单位疫苗等。论文就羊用布鲁菌病疫苗的应用及新型疫苗的研究现状进行综述,以期为羊布鲁菌病的预防提供参考。  相似文献   

8.
布鲁菌病是由布鲁菌引起的人兽共患传染病,接种疫苗是预防和控制该病最有效的方法之一。目前国内外使用的疫苗主要是减毒活疫苗,这种活疫苗具有一定的毒力,但不能区分野毒感染与疫苗免疫产生的抗体,会干扰该病的检疫,国内外许多研究者致力于基因缺失标记疫苗。论文综述了近年来布鲁菌基因缺失疫苗株的研究及应用概况,以加深对布鲁菌病新型疫苗的认识。  相似文献   

9.
刘传运 《兽医导刊》2016,(6):224-225
在动物疫病防控工作中,采用兽用生物疫苗免疫是最好的方法之一.但在接种疫苗的动物群体中,不同个体的免疫应答程度都有差异,免疫应答的强弱或水平高低呈正态分布,因而绝大多数动物在接种疫苗后都能产生较强的免疫应答,但因个体差异,会有少数动物应答能力差,因而在遇强毒感染时,不能抵抗攻击而发病.笔者认为影响疫苗免疫效果的因素主要有以下七个因素.  相似文献   

10.
免疫应答是一种生物学过程,受多种因素的影响.在接种疫苗的动物群体中,不同个体的免疫应答程度都有差异,有的强一些,有的较弱,免疫应答的强弱或水平高低呈正态分布,因而绝大多数动物在接种疫苗后都能产生较强的免疫应答,但因个体差异,会有少数动物应答能力差,因而在有强毒感染时,不能抵抗攻击而发病.如果群体免疫力强,则不会发生流行;如果群体抵抗力弱,则会发生较大的疾病流行.影响疫苗免疫效果的因素主要有:  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

13.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

14.
15.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

16.
A survey of gastrointestinal parasite infections of young (<6 months old), immature (6–12 months old) and adult (>12 months old) dairy cattle on 16 farms in Kiambu District, Kenya was conducted during a dry season (September 1991 to January 1992) and during a wet season (March to July 1992). The survey was based on monthly coproparasitological examination of cohorts and worm counts in tracer calves. The effects of age, sex, farm and season on the prevalence and intensity of helminth and coccidial infections were determined. Faecal egg and oocyst counts revealed that the overall prevalences were: strongyles (including trichostrongyles) (85.5%), liver flukes (Fasciola gigantica) (34.0%), coccidia (30.9%) and tapeworms (9.6%). Eight species of the protozoan Eimeria were identified, the most prevalent species being E. bovis and E. zuernii. The most prevalent nematode genera were Haemonchus, Cooperia, Oesophagostomum and Trichostrongylus. Season, farm and age of the animals had a significant (p<0.05) influence on the intensity of infection with strongyles, liver flukes and coccidia, whereas the sex of the animals had no significant (p>0.05) effect on the prevalence or intensity of infections. A higher intensity of infection with strongyles and coccidia was found in the wet season than in the dry season (p<0.05). The age-specific intensity was in the following order: for strongyles, immature animals of 6–12 months of age had the highest egg counts, followed by young calves and adults. Calves had significantly (p<0.05) higher oocyst counts than immatures or adults. Liver fluke egg counts did not differ significant (p>0.05) between immatures and adult cattle.  相似文献   

17.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

18.
The ash, silica and certain important micronutrients were estimated in conventional and unconventional feed and fodder resources available in Southern India. Commonly used dry roughages, such as paddy straw, ragi straw, maize kadbi/stalk, jowar kadbi/stalk, bajra stalk and wheat straw, were high in ash (9.9% +/- 0.77%) and silica (6.4% +/- 0.65%) and low in most of the other micronutrients, except iron, with paddy straw containing most silica (>9%). Cultivated non-leguminous (maize, jowar) and improved green crops (hybrid napier, guinea, green panic, NB-21, CO-1) were also high in ash (10.5% +/- 0.60% and 12.5% +/- 0.51%) but were moderate sources of P, Mg and Cu and good sources of Zn (98 +/- 13.8 ppm and 55 +/- 6.7 ppm). Leguminous green fodders (stylosanthus, lucerne, cow pea, soyabean) were excellent sources of Ca (1.9% +/- 0.16%), Mg (0.40% +/- 0.05%), Cu (30 +/- 5.2 ppm), Zn (121 +/- 14.7 ppm) and Fe (1234 +/- 166 ppm) and moderate sources of P. Mixed local grasses and weeds were high in silica (6.9% +/- 1.00%) but were good sources of Cu, Zn and Fe. Cereal grains (maize, wheat, rice, ragi) were low in ash (2.9% +/- 0.33%) and were relatively poor sources of Ca (0.22% +/- 0.03%), Mg (0.19% +/- 0.03%) and Cu (13 +/- 3.1 ppm). Pulses were low to medium sources of most minerals and good sources of Fe (1230 +/- 293 ppm). Oil seed cake/extractions (groundnut cake, cotton seed cake, soyabean meal, sunflower cake, safflower cake) and cereal by-products (rice polish, rice bran, wheat bran) were excellent sources of P (1.1% +/- 0.47% and 2.3% +/- 0.19%) and good sources of Zn (65 +/- 3.9 ppm and 66 +/- 10.7 ppm) and Fe (938 +/- 130 ppm and 662 +/- 126 ppm). Among the unconventional feeds screened, orange peel, sunflower heads, meat meal, rubber seed cake, spirulina algae and sea weeds contained plentiful Ca, Zn and Fe: tree leaves/top feeds (mulberry, erythrina, glyricidia, banana, subabul, groundnut haulms) were excellent sources of Ca (1.5% +/- 0.13%), Zn (120 +/- 22.9 ppm) and Fe (1033 +/- 133 ppm) but relatively poor sources of P. Soyabean husk, cocoa seed husk, rubber seed cake and meat meal were moderate to good sources of P (1.0% and 0.33%). The high Zn and Fe values of most feeds/fodders were probably due to soil contamination. This account of the micronutrient content of feed/fodder resources should help in strategic supplementation intended to alleviate local deficiencies.  相似文献   

19.
Bovine Mastitis in Selected Areas of Southern Ethiopia   总被引:3,自引:0,他引:3  
A study on bovine mastitis, designed to determine the causal agents, prevalence of infection and impact of risk factors in three cattle breeds, was conducted in selected areas of southern Ethiopia. A total of 307 lactating and non-lactating cows, of which 162 were indigenous Zebu, 85 Jersey and 60 Holstein-Friesian, were examined by clinical examination and the California mastitis (CMT) test. Of these, 40.4% were positive by CMT and bacteriology for clinical or subclinical mastitis, with prevalence rates of 37.1% and 62.9%, respectively. Out of 1133 quarters examined, 212 (18.7%) were found to be infected, 83 (39.2%) clinically and 129 (60.8%) subclinically. The prevalence of mastitis was significantly higher in Holstein-Friesian than in indigenous Zebu, in non-lactating cows than in lactating cows, in the early lactation stage than in the mid-lactation stage, in cows with lesions and/or tick infestation on skin of udder and/or teats than in cows without this factor, and in the wet season than in the dry season. Mastitis increased with parity number (R = 0.9). Of 248 CMT and clinically positive udder quarter samples analysed microbiologically, 212 were culturally positive for known mastitis pathogens and 36 were negative. Of the 199 positive samples, Staphylococcus accounted for 39.2%, Streptococcus for 23.6%, coliforms for 14.1%, Micrococcus and Bacillus species for 8.0% each and Actinomyces or Arcanobacterium (Corynebacterium) for 7.0%. It was concluded that there was a high prevalence of clinical and subclinical mastitis, mainly caused by Staphylococcus aureus, Streptococcus agalactiae and Escherichia coli, in this study area.  相似文献   

20.
不同日粮氮水平对山羊氮代谢和微生物蛋白质合成的影响   总被引:2,自引:0,他引:2  
本试验旨在探讨不同日粮氮水平对内蒙古白绒山羊氮代谢和微生物蛋白质合成(MCP)的影响,以达到提高氮利用率,减少环境污染和饲料资源的浪费。试验选用9只体况良好、体重为(43.83±2.95)kg,装有瘤胃瘘管的内蒙古白绒山羊,按体重随机分为3组,每组3只。日粮分为低氮7.5%、中氮10.5%、高氮13.5%3个氮水平。试验使用常规试验方法分析测定粪尿血液等生化指标,通过全收尿法和尿嘌呤衍生物法估测MCP。结果表明:随着氮水平增加,氨氮(NH3-N)浓度、氮摄入量、尿氮排出、尿中尿素氮(UUN)和MCP显著增加(P0.05),干物质采食量(DMI)显著降低(P0.01);沉积氮占总摄入氮的比例在中氮组最高,MCP在高氮组最高。综上所述,适当降低日粮氮水平可减少粪尿氮排放,提高反刍动物氮利用率。  相似文献   

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