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1.
采用反转录-聚合酶链反应(RT-PCR),从1株传染性法氏囊病病毒(IBDV)本地分离株GZ902中扩增到编码IBDV主要免疫蛋白VP2的cDNA片断,大小约为1350bp。将该cDNA片断插入pBsK质粒中,用重组质粒转化大肠杆菌XL1-Blue,成功获得重组质粒转化菌。对重组质粒DNA进行酶切鉴定,证明插入的DNA片断与PCR扩增的DNA片段大小相符。对GZ902高可变区进行了序列分析。其核苷酸序列与3株IB-DV变异株A、GLS、E的同源性分别达到98.9%,96.2%和95.5%。而与其他Ⅰ型毒株的同源性较低。比较从DNA序列推导出的氨基酸序列,发现GZ902高可变区的两个亲水区均发生了一个氨基酸的变化,而在249和254位上的氨基酸分别为K和S,与以上3个变异株相同,但与所有标准Ⅰ型毒株不同。这两个氨基酸可以作为IBDV变异株的标志。  相似文献   

2.
以鸡新城疫病毒(NDV)澳大利亚布里斯班分离株R95的 RNA为模板,运用的RT-PCR技术扩增其融合蛋白(F0)基因的cDNA。将扩增的F基因克隆到质粒PUC19中,转化入大肠杆菌JM109中,经AIX平板筛选,PCR等方法鉴定出F基因的阳性重组质粒,同时测定了F基因5’端709个核苷酸及3’端768个核苷酸的序列,对相应的氨基酸序列的研究表明,B95株属弱毒株,含有F0中保守的疏水功能区和可糖基化位点,B95与强毒株F48E8株、Miyadera株和中等毒力的Beaudette C株的氨基酸序列的同源性在90%左右。  相似文献   

3.
新城疫病毒弱毒株分子生物学特性的研究   总被引:3,自引:0,他引:3  
于1996年从长春地区一养鸡场分离到一株新城疫病毒(NDV长春株),经过病毒生物学特性的研究表明该NDV毒株为弱毒株。将NDV长春株纯化培养后,提取病毒RNA,经RT-PCR扩增F基因,并测定出F基因的全部核苷酸序列为1758bp,编码有553个氨基酸残基。与国内外发表的部分NDV病毒的强毒株和弱毒株的相同序列进行比较,其核苷酸同源性在88.2% ̄96.7%之间,氨基酸同源性在90.1% ̄98.1%之间,并与所有弱毒株F蛋白裂解位点区(112 ̄117)氨基酸序列Gly-Arg/Lys-Gln-Gly/Ser-Arg-Leu相同,从基因和分子水平上进一步证明NDV长春株为NDV弱毒株。  相似文献   

4.
中国肾型IBV毒株的基因型及其S1基因的巢式PCR   总被引:1,自引:0,他引:1  
用本研究建立的IBVS1基因的巢式PCR方法鉴定了国内5个肾型传染性支气管炎病毒(IBV)分离株。以此5个分离株及3个标准毒株的RT-PCR产物(1749bp,含S1基因)为模板,1对内部引物经巢式PCR都获得1729bp的产物,另1对内部引物的巢式PCR有大小不同的产物(1678bp或0.5、0.6kb)。参照以前的RFLP分析结果,探讨了中国肾型IBV毒株的基因型状况。  相似文献   

5.
为了证明我国马传染性贫血病毒(EIAV)驴白细胞弱毒株的长末端重复序列(LTR)是否能够启动基因的表达,我们将该LTR克隆于含CAT基因的载体中,获得重组质粒pCAT-LTR,用pCAT-LTR分别转染驴胎皮肤细胞(FDD)、胶质母细胞瘤(TJ-905)细胞、驴白细胞及接种EIAV弱毒的FDD及驴白细胞,结果以EIAV弱毒的LTR为启动子,CAT在这几种细胞中均获得了不同程度的表达,证实了我国EIAV弱毒株的LTR在FDD、TJ-905及驴白细胞中确实具有一定的启动子功能,并能被反式激活表达,为进一步研究EIAV弱毒复制及表达调控奠定了基础。  相似文献   

6.
根据已发表的传染性喉气管炎病毒(ILTV)SA-2株的核酸序列,设计了1对引物,以ILTV-中国王岗株DNA为模板,PCR法扩增出1条1.39kb的基因片段,将扩增产物插入到真核表达质粒pCR^TM3-Uni,得到重组质粒pTA-gD,另将克隆到pBluescript SK质料中的gC基因酶毁后,插入到pCR^TM3-Uni载体,得到重组质粒pTA-gC,经电泳分析、酶分、PCR鉴定后,进行序列测  相似文献   

7.
多聚酶链反应区分血清Ⅰ型MDV强弱毒株   总被引:1,自引:0,他引:1  
选用血清Ⅰ型马立克氏病病毒(MDV_1)基因组中位于132bp正向重复序列两侧的2段寡聚核苷酸为多聚酶链反应(PCR)的引物,分别对Ⅰ型MDV强毒株(京-1株)和弱毒株(Md11/75C株)的核酸进行基因扩增。结果显示:该弱毒株核酸基因中含6个或更多个拷贝数的132bp正向重复序列,而强毒株核酸基因中仅含2个,相同引物对Ⅱ型、Ⅲ型MDV(SB-1株,Fc126株)和禽网状内皮组织增生病病毒(REV)核酸作PCR扩增,未检出任何核酸片段。  相似文献   

8.
采取马传染性贫血病毒(EIAV)辽宁野毒株(L株)感染马的血液,分离白细胞。提取白细胞中的DNA,并以此为模板,利用PCR技术分四个片段扩增 EIAV前病毒 DNA。将其分别克隆到载体质粒 pBluescript SK中,经酶切鉴定后测序。对测序结果分析、拼接,得到 EIAV  L株前病毒基因组全序列。  相似文献   

9.
将北京地区猪系列与呼吸综合征病毒(PRRSV)分离BJ-2和BJ04的ORF7及部分3端编码区(UTR)的RT_PCR扩增产物克隆连接于pGEM-Teasy质粒载体上,重组质粒经EcoRⅠ酶切鉴定后进行了双链测序。测定垢基因序列与欧已知序列比较发现,BJ-2和BJ-4株与美洲VR-2332株非常接近,在其长度为555bp的cDNA序列中,仅与VR-2332株分别相差1和2个核苷酸,其中ORF7的核  相似文献   

10.
家蚕核型多角体病毒IE-1基因启动子的克隆和序列分析   总被引:2,自引:0,他引:2  
利用PCR方法扩增了家蚕核型多角体病毒苏州株(BmNPVsu)的IE-1启动子全序列并进行克隆和序列分析,结果表明BmNPVsu的BmNPVsu启动子符合真核生物启动子特点,在其序列中有典型的增强子类似元件、加帽位点、TATA盒等基序。与GenBank报道的其它几种NPV病毒基因组中的IE-1启动子序列进行同源性分析表明BmNPVsu与IE-1(家蚕核型多角体病毒T_3株)、AcMNPV(首蓿尺蠖核型多角体病毒)、OpMNPV(黄衫毒蛾核型多角体病毒)、LdNPV(舞毒蛾核型多角体病毒)的同源性分别为99.5%、96.4%、66.2%和50.2%。根据各NPV基因组中IE-1启动子序列分析了几种NPV的进化关系。  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.
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   

13.
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   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
A microsporidial keratopathy is described in two dogs. Both dogs presented with a unilateral stromal keratopathy characterized by multifocal coalescing opacities, and the diagnosis was made on histopathologic examination of keratectomy specimens. Transmission electron microscopy (TEM) on formalin‐fixed, paraffin‐embedded corneal tissue was performed in one dog, and the morphologic features were consistent with Nosema species infection. Both dogs were initially diagnosed and treated by superficial keratectomy. One dog received additional antifungal medication and underwent a penetrating keratoplasty following local recurrence two years later. No other systemic lesions attributable to the microsporidial infection were identified clinically. The clinical and diagnostic pathology findings, treatment, and follow‐up are discussed.  相似文献   

20.
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