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1.
为构建一株表达狂犬病病毒(RV) G蛋白的重组犬瘟热病毒(CDV),本研究以本实验室分离的CDVSnyder Hill疫苗株为基础,在CDV P和M基因之间插入RV弱毒疫苗株ERA G蛋白基因,构建重组质粒p CI-CDV-RVG及表达CDV N、P和L蛋白的辅助质粒p CI-CDVN、p CI-CDVP和p CI-CDVL,将重组质粒和辅助质粒共转染BSR细胞,拯救获得了表达RV G蛋白的重组犬瘟热病毒(rCDV-RVG),将该重组病毒在Vero细胞中传代,通过RT-PCR、间接免疫荧光试验(IFA)和western blot鉴定。结果显示RV G基因能够在r CDV-RVG中稳定存在并正确表达。病毒生长动力学曲线显示,重组病毒在Vero细胞中的增殖效率与拯救的亲本病毒r CDV无显著差异(p0.05)。本研究表明CDV Snyder Hill株作为载体表达外源基因的潜力,为研制高效、安全、廉价的CDV-RV二联活载体疫苗奠定基础。  相似文献   

2.
为获得果子狸源呼肠孤病毒(MRV)Masked Palm Civet/China/Liu/2004(MPC/04)株的全基因序列,本研究根据GenBank中登录的哺乳动物MRV基因序列设计了22对引物,运用RT-PCR技术对该毒株的各个基因片段进行了扩增和同源性分析,并绘制系统发育进化树。结果显示该毒株L1、L2、M1和S3基因核苷酸序列与SARS病人体内分离到的SARS病毒T2/BYD1/human/Song/2006(T2S)株同源性较高,该病毒株L3、M2、M3、S1、S2和S4基因核苷酸序列与病猪体内分离到的MRV株SC-A/pig/Zeng/2006(SC-A)同源性较高,系统发育进化树同样表明各个病毒株的不同基因节段均具有不同的进化过程,推测MRV不同病毒株之间存在重配现象。通过MPC/04株S1基因同源性分析和核苷酸系统发育进化树分析,表明该病毒株S1基因与MRV血清3型的S1基因同源性较高,而与其它血清型的同源性较低,因此初步判断该病毒株血清型为血清3型。  相似文献   

3.
羊口疮病毒黑龙江省分离株的分离鉴定   总被引：1，自引：0，他引：1  
为确定黑龙江大庆地区某羊场发生的疑似羊口疮(Orf)的病原,本研究采用MDBK细胞培养途径从病羊的口唇部位的痂皮病料中分离出1株病毒.通过电镜观察和IFA鉴定证明该分离株为Orf病毒,命名为OV/HLJ/04.其F1L基因核苷酸序列测定和进化分析显示,OV/HLJ/04与国内报道的山西株(HQ221964)的遗传关系密切,同源性达到98.2％.将该病毒分离株进行回归本动物试验,接种羔羊发生严重的羊口疮.  相似文献   

4.
为制备A组猪轮状病毒(Po RV)非结构蛋白NSP3的单克隆抗体(MAb)及鉴定其抗原表位,本研究将原核表达、纯化的重组NSP3蛋白(r NSP3)免疫BALB/c小鼠,取免疫小鼠的脾细胞与SP2/0细胞进行融合,经间接ELISA法筛选,得到一株能够稳定分泌抗Po RV(G9)的杂交瘤细胞株(5B8)。MAb鉴定结果显示其抗体亚类为Ig G1型;MAb细胞培养上清液效价为1∶103,western blot及间接免疫荧光结果表明该株MAb能够与Po RV反应。对NSP3蛋白进行截短表达,采用western blot试验确定所获得的MAb识别的抗原表位区域序列为290QDYD RTFL297。该MAb的制备为进一步研究NSP3蛋白的结构和功能奠定了良好的基础。  相似文献   

5.
为研究分离自黑龙江三江自然保护区的野生绿头鸭粪拭子中的一株新城疫病毒(命名为Mallard/CH/HLJ383/06)主要生物学特性及基因组序列,本实验对病毒F基因序列进行测定,结果表明该病毒分离株属于NDV基因Ⅲ型,病毒的1日龄雏鸡脑内致病指数(ICPI)为1.81,高于NDV中等毒力病毒株ICPI值,预示该病毒分离株毒力有增强趋势.15日龄SPF鸡致病性试验表明,该病毒分离株可导致雏鸡发病但不死亡,致病性仍低于与其ICPI值相近的基因Ⅶ型毒株.对该病毒分离株进行全基因组序列分析表明:该病毒分离株与Ⅰ系疫苗病毒Mukteswar、江苏2株基因Ⅲ型分离株(JS/7/05/Ch,JS/9/05/Go)结构蛋白氨基酸同源性高达99.0%～99.7%;与疫苗株Mukteswar相比,3株基因Ⅲ型病毒分离株在F蛋白中只有1个共同的氨基酸位点变异(A203T);HN蛋白中存在15个变异氨基酸,但位置各不相同;L蛋白中变异位点最多,为28个,其中有4个变异位点为3个分离株所共有.以上结果初步表明,Mallard/CH/HLJ383/06株可能是由疫苗株Mukteswar在野禽、家禽生态系统中传播进化而来,并由于宿主或免疫压力而发生毒力变异;分离株L蛋白氨基酸位点的变异,可能是导致病毒株毒力返强主要因素之一.  相似文献   

6.
为构建包装含有H1亚型流感病毒HA蛋白的伪型病毒,本研究将人工合成的H1N1流感病毒(A/Califorma/04/2009株)血凝素(Hemagglutinin,HA)基因连接至真核表达载体pcDNA3.1,该重组质粒与表达逆转录病毒相关元件的骨架质粒pHIT111及pHIT60共转染人胚胎肾细胞293T,构建了以鼠白血病病毒为核心、包装含有HA蛋白的伪型病毒.通过对伪病毒感染细胞中LacZ报告基因表达产物的检测,证明伪病毒可以感染MDCK细胞;同时其感染过程可被流感病毒免疫后的小鼠阳性血清所阻断,表明该伪型病毒可模拟野生型病毒完成对宿主细胞的感染过程.本研究所构建的伪病毒系统为研究H1亚型流感病毒HA蛋白抗原特性及新型中和抗体检测方法的建立提供了理想的工具.  相似文献   

7.
本研究使用Vero细胞复苏繁殖猪流行性腹泻病毒(Porcine epidemic diarrhea virus,PEDV)DR13株,并通过蔗糖梯度超速离心、SDS-PAGE电泳纯化PEDV DR13株的N蛋白和M蛋白.结果PEDV DR13株具有致Vero细胞病变能力,TCID50为105.12/mL;获得的PEDV...  相似文献   

8.
为建立马动脉炎病毒(EAV)的快速检测方法,本研究设计了一对针对EAV Bucyrus株ORF7基因序列的特异性引物,建立了检测EAV的Eva Green荧光定量RT-PCR (qRT-PCR)方法.结果表明,该方法在102拷贝/μL～107拷贝/μL范围内具有良好的线性关系;最低检出量为1015 TCID50/mL病毒,敏感性为常规RT-PCR的100倍,与其他马常见病毒无交叉反应;组内及组间重复性试验的变异系数均小于2％,具有较好的重复性.此外,采用该方法测定了EAV Bucyrus株及其拯救病毒icEAV感染RK-13细胞后的复制动态,并与TCID50方法进行了比较.结果显示icEAV与其亲本病毒接种RK-13细胞后,0h测定病毒TCID50及拷贝数分别为103.33TCID50/mL(1 04 65拷贝/2μL)和10350 TCID50/mL(104 70拷贝/2μL);60 h时,细胞病变达到100％,icEAV及其亲本病毒的TCID50及拷贝数分别为105.67TCID50/mL(107 0拷贝/2μL)和105.57 TCID50/mL(106 98拷贝/2μL),两株病毒在RK-13细胞内的复制效率相似.本研究建立的Eva Green qRT-PCR方法可以为细胞培养物中EAV的检测提供有效的技术手段.  相似文献   

9.
家蚕质型多角体病毒RNA聚合酶的基因克隆及鉴定   总被引：1，自引：1，他引：0  
RNA依赖的RNA聚合酶(RNA-dependent RNA polymerase,RDRP)是RNA病毒增殖复制的重要酶类,具有转录酶和聚合酶的双重活性.家蚕质型多角体病毒(Bombyxmoii cytoplasmic polyhedrosis virus,BmCPV)是呼肠孤病毒科,质多角体病毒属的代表种,为双链RNA病毒.已有的BmCPV冷冻电镜三维重构的研究结果表明,在病毒衣壳五重轴的内表面各有一花形结构,位于B-突起(B-spike)的近内侧,推测为转录酶复合物(TEC),可能是BmCPV结构蛋白VP2的对应成分.  相似文献   

10.
为构建表达鸡传染性支气管炎病毒(IBV)主要免疫原S1蛋白的重组腺病毒,本研究以复制缺陷型人5型腺病毒为载体,以IBVCK/CH/LHLJ/04V株S1基因为外源插入靶基因,通过细菌内同源重组法构建了一株稳定表达IBVS1蛋白(90ku)的重组腺病毒,命名为rAdV-S1。通过PCR鉴定、间接免疫荧光及western blot检测证实S1蛋白在重组腺病毒中获得表达。对构建的重组腺病毒和亲本腺病毒的生长动力学分析表明,该重组病毒的毒价为108.25TCID50/mL,并且两者在生长动力学方面无显著差异。本研究为动物试验和该重组腺病毒免疫特性的研究奠定基础。  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.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

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.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

17.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

18.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

19.
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   

20.
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   

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