首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 62 毫秒
1.
犬冠状病毒核酸探针的制备及其基因序列的测定与比较   总被引：1，自引：0，他引：1  
采用RT-PCR方法扩增犬冠状病毒(CCV)YS1、C11和NL-18株5′端部分S基因序列,以随机插入DNA法对CCV YS1株纯化的PCR产物标记32P同位素,制备核酸探针,并与3株CCV反转录产物杂交.用平端连接法将3株CCV PCR产物克隆于pUC19 Sma I位点或pGEM-T载体中,经PCR鉴定为正确重组质粒.以双脱氧末端终止法测定了重组质粒的cDNA核苷酸序列,并用DNASIS计算机软件进行多重比较分析,绘制系统树.结果表明,所制备的核酸探针可与3株CCV反转录产物杂交,其核苷酸序列与多株CCV相应序列的同源性高达91.9%～99.1%,为CCV的保守区.由此说明,制备的核酸探针可用于犬CCV感染的分子流行病学研究.  相似文献   

2.
采用RT—PCR方法扩增犬冠状病毒(CCV)YSl、CI1和NL—18株5’端部分S基因序列，以随机插入DNA法对CCV YSl株纯化的PCR产物标记^32P同位素，制备核酸探针，并与3株CCV反转录产物杂交。用平端连接法将3株CCV PCR产物克隆于pUCl9 SmaI位点或pGEM—T载体中，经PCR鉴定为正确重组质粒。以双脱氧末端终止法测定了重组质粒的cDNA核苷酸序列，并用DNASIS计算机软件进行多重比较分析，绘制系统树。结果表明，所制备的核酸探针可与3株CCV反转录产物杂交，其核苷酸序列与多株CCV相应序列的同源性高达91．9％-99．1％，为CCV的保守区。由此说明，制备的酸破探针可用于犬CCV感染的分于流行病学研究。  相似文献   

3.
为提升口岸进出境犬猫科动物检疫工作效率,针对犬冠状病毒(CCV)基因保守序列,设计特异性引物和荧光探针,建立了CCV实时荧光重组聚合酶等温扩增方法(real-time RPA)。结果表明,该方法具有良好的特异性,与其他犬病毒和同属的冠状病毒均未出现交叉反应;其敏感性高于传统的RT-PCR方法;将该方法应用于CCV感染犬的临床组织样本、体表样本及不同时期和地区分离样本的检测,证实该实时荧光RPA方法具有良好的稳定性和可靠性。与现有的核酸检测方法相比,该实时荧光RPA检测方法在核酸上样20 min内即可判读结果,可满足犬猫科动物CCV快速检疫的需要。  相似文献   

4.
RT-PCR检测犬粪便中的冠状病毒   总被引：1，自引：2，他引：1  
根据犬冠状病毒(caninecoronavirus, CCV) 的S基因序列, 用计算机设计并合成了1对引物P1、P2, 以此引物及以从美国进口的CCV疫苗的反转录产物为模板, 初步建立了检测CCV的RT PCR。将纯化的PCR产物成功地克隆到pGEM T easy载体中, 鉴定、测序并进行同源性分析。结果表明, 与1 71和UCD 1株同源性分别为91 5%和94 3%。该RT PCR能对疫苗中CCV及CCV参考株USCV B1的S基因进行特异性地扩增,长度为575bp, 对犬的其他病毒及CRFK细胞未能扩增出任何片段, 该RT PCR能检测出0 5μLCCV培养液/2g粪便。用建立的RT PCR在上海对50条犬粪便进行检测, 结果表明CCV阳性6例。本研究建立了检测犬粪便中的CCV的RT PCR, 能用于犬冠状病毒流行病学调查。  相似文献   

5.
以地高辛(DIG)标记鸡传染性支气管炎病毒(IBV)pol基因的保守片段制成核酸探针,与IBV参考株、新城疫病毒、传染性法氏囊病病毒、禽流感病毒、正常鸡胚尿囊液及正常鸡肾组织等的RT-PCR产物进行斑点杂交,以检测探针的特异性,结果该探针仅与IBV毒株的RT-PCR产物杂交呈阳性,与对照病毒和组织的RT-PCR产物杂交呈阴性.敏感性试验显示,探针最低能检出约3.4pg的IBV RT-PCR产物.用该方法检测了38份疑似IBV临床病料,31份阳性;而用RT-PCR法扩增IBV S2基因确诊为阳性的只有29份.对人工接种IBV H52弱毒苗鸡咽喉和肛门拭子32份进行检测,检出15份阳性.结果表明,利用DIG探针检测IBV的RT-PCR产物,特异性和敏感性强,可重复,能克服RT-PCR非特异性反应和探针Northern杂交的不稳定性.  相似文献   

6.
早在 8 0年代中期 ,国外就已研制出弱毒苗和灭活苗对犬进行免疫研究 [1,2 ] ,国内开展犬冠状病毒( CCV)的研究起步较晚 ,但发生 CCV性肠炎的报道很多 ,且远比国外报道的严重。 1 997年 ,胡桂学等 [3 ]利用犬胎原代细胞从一肠炎犬病料中成功分离获得 1株 CCV强毒 YS1株 ,随后我们采用静水压和 BEI灭活病毒的方法对该株强毒进行灭活 ,研制出两种新型的犬冠状病毒灭活苗 ,并对犬进行了免疫试验 ,同时我们还应用反转录 -聚合酶链反应( RT- PCR)技术对免疫后犬组织中的犬冠状病毒进行检测 ,并设立了传统的犬冠状病毒福尔马林灭活苗免疫犬…  相似文献   

7.
电镜观察磷钨酸负染的大熊猫肝脏分离病毒细胞培养物,发现冠状病毒样粒子.细胞培养物超薄切片上可见细胞浆内病毒包涵体.理化学和生物学特性研究结果表明,病毒对氯仿、乙醚敏感,可耐受1 %胰蛋白酶的作用,具有一定的耐酸性和耐热性;病毒对FCWF细胞敏感,对Vero细胞不敏感,无血凝性和血吸附特性.采用犬冠状病毒阳性血清,经中和试验确定该分离病毒是一株犬冠状病毒,命名为CCV DXMV.以犬冠状病毒特异性PCR引物,可以从大熊猫肝脏组织和不同代次的病毒细胞培养物中,扩增出目的核苷酸片断.序列分析结果表明,该株病毒部分纤突蛋白基因序列与分离自美国的CCV NVSL株相应基因序列的同源性高达100 %.  相似文献   

8.
采用蔗糖密度梯度离心,纯化浓缩犬冠状病毒(CCV)、猫冠状病毒(FCV)、猫传染性腹膜炎病毒(FIPV)、猪传染性胃肠炎病毒(TGEV)、猪呼吸道冠状病毒(PRCV)的细胞培养物,分别设计7,17,11,10和4对引物,构建了49个基因片段的克隆。煮沸裂解法制备质粒DNA,回收PCR扩增产物,点制冠状病毒基因芯片。抽提病毒总RNA,利用Cy3-dCTP随机渗入反转录PCR标记,与芯片进行杂交检测,淘汰交叉的克隆片段。结果表明:克隆CCV1,CCV2,CCV5和CCV7可特异诊断CCV,克隆FCV6,FCV7,FCV8和FCV9可特异诊断FCV,克隆FIPV2,FIPV7,FIPV8和FIPV9可特异诊断FIPV,克隆PRCV1,PRCV2和PRCV3可特异诊断PRCV,克隆TGEV3,TGEV4,TGEV5和TGEV6可特异诊断TGEV。将这些特异克隆扩增片段重新点制基因芯片,与病毒PCR产物杂交,未发现交叉现象。基因芯片检测比传统PCR敏感1000倍,可有效应用于这5种动物冠状病毒的检测与区分。  相似文献   

9.
大熊猫犬冠状病毒的分离与鉴定   总被引：11，自引：2，他引：11  
以犬肾传代细胞(MDCK)从1只病死大熊猫肝脏中分离到1株病毒,命名为DXMV。电镜观察磷钨酸负染的病毒细胞培养物，发现冠状病毒样粒子，超薄切片上可见细胞浆内病毒包涵体。理化学和生物学鉴定结果表明，DXMV核酸类型为RNA，对氯仿、乙醚敏感，可耐受1％胰蛋白酶的作用，具有一定的耐酸性和耐热性，可在MDCK、FCWF、F81细胞中增殖，无血凝性和血吸附特性。血清中和试验结果表明，DXMV可被犬冠状病毒阳性血清中和。采用犬冠状病毒间接荧光抗体法染色DXMV细胞飞片，可在细胞浆内见到特异性荧光。以冠状病毒通用引物和犬冠状病毒特异性引物，可从大熊猫肝脏和不同代次的病毒细胞培养物中扩增出与预期值251bp和515bp大小相同的核苷酸片段。由此说明，该病毒为犬冠状病毒，大熊猫可被犬冠状病毒感染。  相似文献   

10.
犬冠状病毒 ( CCV)是引起犬发生冠状病毒性肠炎的一种重要病原 ,由于该病毒在普通细胞上培养需较长时间 ( 3～ 6天 )才出现病变 ,且病变不明显 ,不易观察 ,难以广泛开展该病毒的鉴定、克隆、滴定及中和抗体的检测等研究工作。本实验以琼脂糖作为覆盖物 ,在 DK细胞上 ,对该病毒蚀斑的形成条件进行了摸索 ,建立了犬冠状病毒的蚀斑形成方法 ,并以该方法进行了 CCV YS1株的克隆纯化 ,结果较为理想 ,现报告如下。1　材料与方法1 .1　病毒株　犬冠状病毒 YS1株 ,从 CCV肠炎犬病料中分离获得 ,人工感染犬试验 [1]表明其为一株免疫原性良好的…  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.
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   

16.
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   

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.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号