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Subgroup-specific peptide-based enzyme-linked immunosorbent assays from the G-protein of the ovine and bovine respiratory syncytial virus (RSV), respectively, were used to determine the prevalence of the ovine and bovine subgroup strains of RSV infections in cattle. A total of 1,102 bovine serum samples were obtained from 6 diagnostic laboratories located in the northwestern and the southeastern USA and were tested for antibody to either the bovine or ovine subgroups of RSV. Antibody to viruses from each subgroup was present in samples from each region and all states tested. The Southeast had a higher prevalence of the bovine subgroup strains (69.5%). Then did the Northwest (40.9%). The prevalence of the ovine strain was similar for the two regions (16.7% in the southeast, 14.9% in the northwest). The overall prevalence was 56.6% for the bovine strain and 15.9% for the ovine strain. These results suggest members of the ovine subgroup of RSV circulate in the cattle population but with less frequency than those viruses of the bovine subgroup.  相似文献   

3.
Subgroup-specific peptide-based enzyme immunoassays from each respective G-glycoprotein of the ovine and the bovine respiratory syncytial virus (RSV) were developed to detect RSV-specific IgG responses in cattle. Antigenic peptides from the respective G-glycoprotein were identified from the extracellular central hydrophobic region (amino acids 158-189) located between 2 mucin-rich regions. These antigenic peptides identified by epitope mapping from each G-glycoprotein were synthesized and used to develop the subgroup-specific enzyme immunoassays. The negative cutoff for each enzyme immunoassay was established as the mean optical density of indirect immunofluorescent antibody-negative bovine sera plus 3 SDs. The sensitivity (82.9%) and specificity (100%) of the bovine enzyme immunoassay and the specificity (95.8%) of the ovine enzyme immunoassay were determined by comparison with indirect immunofluorescence (used as the "gold standard"). The negative and positive predictive values were calculated for each assay. The presence of serum antibody to ovine RSV in cattle implies that this virus infects cattle and may contribute to the pathogenesis of bovine respiratory disease.  相似文献   

4.
Two different respiratory syncytial virus (RSV) radiolabeled probes were used to characterize the genetic heterogeneity of 25 ruminant RSV isolates by the ribonuclease protection assay. A 32P-radiolabeled antisense RNA probe was transcribed from cloned ovine and bovine RSV G glycoprotein genes and then hybridized with total RNA isolated from infected cells with various ruminant RSV isolates. The results of this study, along with previously published nucleotide sequence data of the ovine RSV G glycoprotein gene, suggest the presence of at least 2 ruminant RSV subgroups. One subgroup is represented by RSV isolated from respiratory disease outbreaks from calves and goats, and the other is represented by RSV isolated from sheep.  相似文献   

5.
Nucleotide sequences of 16S rDNA and rpoB gene of 25 bovine and 6 ovine Histophilus somni strains were determined to detect subtle differences between the host animal species. The 1465 nucleotide residues of the 16S rDNA exhibited levels of sequence similarities of 99.4% or more. The high sequence similarity of the 16S rDNA of recently described species H. somni was confirmed in the 31 strains from cattle and sheep. These results suggested that the intra-specific diversity of 16S rDNA was limited in bovine and ovine strains of H. somni. The specific association of strains was also observed in the 311 bp region of rpoB gene which sequence similarities were 98.6% or more. However, the phylogenetic tree analysis of the rpoB gene showed that the ovine strains appeared to form a subgroup recovered in 70% of the bootstrap trees. In the 311 bp region of the ovine strains, a HincII restriction endonuclease site was detected. The PCR-amplified rpoB DNA of 46 bovine and 20 ovine H. somni strains were examined for the digestion with HincII. As the results, 17 strains of ovine strains were cleaved by the enzyme but none of the bovine strains appeared to possess the restriction site. The restriction enzyme analysis of rpoB gene may be useful to differentiate ovine strains from bovine strains of H. somni.  相似文献   

6.
Based on the marked antigenic similarities that exist between antigens of the human and bovine strains of respiratory syncytial virus (RSV), an enzyme immunoassay (EIA) designed to detect human RSV was used to detect bovine RSV. The commercial test kit (RSV EIA) consists of a solid phase (beads) coated with a capture antiserum prepared against the Long strain of human RSV. The RSV EIA test was compared with the method of inoculation of cell cultures and fluorescent antibody (FA) staining of lung tissue for the detection of bovine RSV. Using a cell culture-propagated stock of strain 375 of bovine RSV, the threshold of sensitivity of the EIA test for the cattle strain of RSV was determined to be less than or equal to 10(2.3) CCID50/ml. In addition, RSV EIA detected the bovine RSV in nasal samples obtained from 3 experimentally inoculated cattle. The RSV EIA exhibited a sensitivity of greater than or equal to 80% during the period that shedding of infectious virus took place. All of the bovine RSV FA-positive lung samples (n = 37) were positive by the RSV EIA. Twenty-six of the remaining 214 bovine RSV FA-negative lung samples were positive by the RSV EIA. The RSV EIA was also used to test 137 nasal swabs obtained from cases of bovine respiratory disease. Of these, 38 tested positive by RSV EIA. All samples that tested positive by EIA were confirmed by blocking assays using hyperimmune serum anti-bovine RSV and a pool of monoclonal antibodies specific for that virus.  相似文献   

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Respiratory syncytial virus (RSV) causes severe lower respiratory tract infection in children and calves. Antibodies to ovine RSV (ORSV) are common in sheep, but the clinical disease is not well defined. There is no report of ORSV infection in Australian sheep although respiratory distress syndrome has been described. This discrepancy may be due to the lack of a suitable diagnostic test. In this report, we have characterised the ORSV G protein in an attempt to study its relatedness to human and bovine RSV (HRSV, BRSV) and for use in the development of a suitable diagnostic assay. Full length and a truncated variant of ORSV G protein were expressed in mammalian cells and the expressed proteins characterised by indirect immunofluorescence and radioimmunoprecipitation assays. Our results indicate that like HRSV, the ORSV G protein is heavily glycosylated. The expressed protein was membrane bound as well as secreted and could be purified from culture supernatants and may be suitable for use in development of a diagnostic assay.  相似文献   

9.
奶牛传染性鼻气管炎病毒gG基因PCR检测方法的建立   总被引:2,自引:1,他引:1  
本试验旨在建立一种PCR技术,既能快速检测牛传染性鼻气管炎病毒,又能区分同属病毒牛疱疹病毒5型和伪狂犬病病毒。根据基因库中牛传染性鼻气管炎病毒gG基因的特异性引物,建立PCR方法,对牛传染性鼻气管炎病毒参考毒株和阳性样本进行扩增,结果均能扩增出一条463 bp的特异性条带;对同属的牛疱疹病毒5型进行扩增,获得651 bp和431 bp两条带;对同属伪狂犬病病毒进行扩增,获得493 bp的条带;而非相关病毒(如猪呼吸与繁殖综合征病毒等),不能扩增出条带。对牛传染性鼻气管炎病毒的检测灵敏度为2×10-3 PFU/mL。鉴于该方法具有良好的灵敏度和特异性,将在牛疱疹病毒感染诊断和标记疫苗免疫后的鉴别诊断方面具有良好的应用前景。  相似文献   

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牛羊多胎性状的分子遗传基础研究   总被引:8,自引:2,他引:6  
本研究采用了RAPD、PCR RFLP、微卫星、PCR SSCP、序列分析等方法对2个牛品种(秦川牛和荷斯坦奶牛共60头)、6个中国固有绵羊品种(多胎品种小尾寒羊,双胎品种大尾寒羊,单胎品种兰州大尾羊、蒙古羊、同羊和哈萨克羊共197余只`进行了分子遗传基础研究,旨在寻找牛羊多胎性状合适的分子标记,为进一步对牛双胎基因、绵羊多胎基因的探索和高繁殖率牛羊的选育提供科学依据.  相似文献   

12.
A preliminary serological survey of viral antibodies in Peruvian sheep   总被引:1,自引:0,他引:1  
This study reports the sero-prevalence of viral infections in sheep in Peru. Serum samples were collected from 34 mature healthy rams located in 3 different geographic regions of the country (north, central and south). The sera were tested for antibodies to the following viruses: respiratory syncytial virus (RSV); parainfluenza 3 (PI-3) virus; bovine viral diarrhea/border disease (BVD/BD) virus; bovine herpesvirus 1 (BHV-1); bluetongue (BT) virus; ovine progressive pneumoniae (OPP) virus; bovine leukosis virus (BLV). The serological studies showed that 47% were positive for RSV; 82% for PI-3; 3% for BVD/BD virus; 49% for BT virus; 13% for OPP virus. Antibodies were not detected to bovine herpesvirus 1 or to bovine leukosis virus.  相似文献   

13.
牛副流感病毒3型RT—PCR检测方法的建立   总被引:2,自引:0,他引:2  
参照GenBank中公布的牛副流感病毒3型(Bovineparainfluenzavirus3,BPIV-3)全基因序列,针对BPIV-3特异性NP蛋白保守基因设计一对引物,建立了BPIV-3的RT—PCR诊断方法。其最佳扩增退火温度为58.1℃,引物浓度为1.0μmol/L。采用该方法扩增BPIV-3参考病毒.能扩增出425bp预期大小的特异性片段,而扩增牛病毒性腹泻/黏膜病病毒、牛传染性鼻气管炎病毒、牛合胞体病毒、猪瘟病毒以及牛支原体、大肠埃希氏菌、牛巴氏杆菌和沙门氏菌等常见病毒和细菌均呈阴性结果。对参考病毒进行梯度稀释检测,结果证明该法检测BPIV-3的灵敏度可达10^-3FCID50/0.1mL。  相似文献   

14.
Inoculation of lambs with an ovine isolate of respiratory syncytial virus (RSV) by a combined intranasal and intratracheal route resulted in mild respiratory tract illness, with respiratory tract lesions. Lung lesions were characterized by bronchitis and bronchiolitis, hyperplasia of bronchial and bronchiolar epithelium, peribronchiolar and perivascular accumulations of lymphocytes, alveolar septal thickening, and collapse. Respiratory syncytial virus was recovered from the respiratory tract of inoculated lambs, and RSV antigen was demonstrated by immunoperoxidase staining of bronchiolar and alveolar epithelial cell in pneumonic lesions of lambs euthanatized on post-inoculation days 5 and 6. Other primary respiratory tract pathogens were not isolated. Clinical signs of respiratory tract illness or respiratory tract lesions did not develop in the in-contact control lamb. Inoculation of the ovine RSV isolate into calves and deer fawns resulted in infection in both species, and at necropsy, pneumonic lesions were present. A mild to moderate respiratory tract illness developed in the calves, but clinical disease was not seen in the fawns. Lung lesions in fawns were similar to those seen in lambs; lesions in calves were characterized by collapse, scattered areas of parenchymal necrosis, and bronchiolitis. Respiratory syncytial virus was reisolated from the lower respiratory tract of inoculated calves and fawns, and immunoperoxidase-positive epithelial cells were seen in pneumonic lesions. Other primary respiratory pathogens were not detected. Respiratory syncytial virus infection was not demonstrable in control animals that were in contact with inoculated animals.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

15.
Cloning and sequencing of the ovine gamma-interferon gene   总被引:1,自引:0,他引:1  
Cytokines are major modulators of the immune system of all animals. The cloning and expression of recombinant cytokine genes have permitted the analysis of their immune function and role in the control of the immune response to disease and vaccination. While human, murine, and bovine genes have been cloned and sequenced, the cloning of ovine cytokine genes has not yet been reported. As sheep are of dominant economic importance to the Australian farming industry, it is of significance to clone and express these genes to facilitate the development of new and better vaccines and pharmaceuticals. We have initially selected ovine gamma-interferon (gamma-IFN) as a target cytokine gene. By the use of the polymerase chain reaction (PCR), using primers based on the bovine gamma-interferon sequence, we have amplified the ovine gamma-interferon gene from crude messenger RNA extracted from lymphocytes. After cloning and DNA sequencing the gene, we found that ovine gamma-IFN is 93% identical to bovine gamma-IFN in amino acid sequence. This result indicates that the PCR method will be a rapid and efficient means for cloning other ovine cytokine genes.  相似文献   

16.
A virus isolated from a yearling cross-bred ewe was identified as respiratory syncytial virus (RSV) by indirect immunofluorescence and by virus neutralization with bovine RSV antisera. The virus caused a mild conjunctivitis in 3-month-old lambs when inoculated alone. Although clinical signs of pneumonia were not observed, there was gross and microscopic evidence of pulmonary inflammation in the lungs of lambs inoculated with either the sheep RSV isolate alone or in conjunction with Pasteurella haemolytica. Lung lesions in the dual infection were more severe, with approximately 10% of the total lung mass affected. Lavage fluids from lambs inoculated with virus and bacteria contained approximately 3 times more inflammatory cells than from control lambs or lambs inoculated with virus only. The sheep RSV isolate was classified as a mild respiratory pathogen in lambs of this age. Speculations on the potential importance of this virus in interspecies transmission to cattle and goats were discussed.  相似文献   

17.
The present study used an RT-nested-PCR and an immunohistochemistry assay to detect bovine respiratory syncytial virus in tissues from experimentally infected balb/c mice. As a first step, Chicken Embryo Related (CER) cell monolayers infected with the BRSV-25-BR strain isolated in Brazil were used for antigen production. Then, the infected lung and tracheal tissues of female balb/c mice were collected on 3, 5, 7 and 10 days post-infection and submitted to both techniques. Primers specific to F and G genes that amplify fragments of 481 bp and 371 bp, respectively, were used. The BRSV detection was not successful in all of the animals tested. The genomic fragment of the G gene from the organs of some infected mice on all analyzed post-infection days was amplified. However, in the RT-nested-PCR corresponding to the F gene, it was not possible to observe any amplified fragment. This was probably due to the higher sensitivity of the developed technique to amplify the fragment corresponding to the G gene compared to the F gene. Moreover, only three of the lungs collected five days post-infection were positive by immunohistochemistry. To the author's knowledge, this is the first study reporting bovine respiratory syncytial virus detection in balb/c mice after experimental inoculation.  相似文献   

18.
Seventy-six percent of 49 blood samples from Saskatchewan cattle had serum antibodies against bovine respiratory syncytial virus. Experimental infection of one week and seven month old calves with bovine respiratory syncytial virus (Iowa strain) caused transient fever, mucopurulent nasal discharge and coughing but no macroscopic or microscopic lesions attributable to bovine respiratory syncytial virus.  相似文献   

19.
A seroepidemiological study of the association between antibody titers to infectious bovine rhinotracheitis, parainfluenza-3, bovine virus diarrhea and bovine respiratory syncytial viruses, and treatment for bovine respiratory disease was conducted. A total of 322 calves from five different groups were bled on arrival, then one month later all cases (cattle treated for bovine respiratory disease) were rebled together with an equal number of controls (cattle not treated for any disease). Titers to these viruses varied significantly from group to group. Based on seroconversion, infectious bovine rhinotracheitis virus was active in 4.4%, bovine virus diarrhea virus in 24%, parainfluenza-3 virus in 69.5% and bovine respiratory syncytial virus in 71.3% of the cattle. Cattle with low titers to infectious bovine rhinotracheitis and/or bovine respiratory syncytial viruses on arrival, were at increased risk of subsequent treatment for bovine respiratory disease. Treated cattle also had significantly greater increases to parainfluenza-3 and/or bovine virus diarrhea viruses than control calves. Treatment rates varied considerably from group to group and were not strongly correlated with weight gain in the postarrival period.  相似文献   

20.
试验旨在扩增秦川牛Snail2基因,构建Snail2基因在其各组织不同发育阶段及脂肪细胞不同分化时期的时空表达规律,为进一步研究Snail2基因在牛脂肪沉积中的功能及调控作用奠定基础。以秦川牛为研究对象,经PCR扩增得到Snail2基因CDS区序列,运用生物信息学软件对其功能结构进行预测,同时采用实时荧光定量PCR检测Snail2基因在新生牛和成年牛各组织及脂肪细胞成脂分化过程中的时空表达谱。结果显示,秦川牛Snail2基因编码序列全长为952 bp。不同物种系统进化树结果表明,牛Snail2蛋白在家牛、水牛、山羊、绵羊中高度保守。磷酸化位点分析发现,存在41个潜在磷酸化位点,其中周期蛋白依赖性激酶1(cyclin dependent kinase 1,CDK1)、CDK5、CKⅡ、CKⅠ等多个细胞周期相关激酶参与了Snail2蛋白的磷酸化修饰。蛋白结构域预测发现,牛、人和鼠等8个物种中有8个相似Motif。Snail2蛋白二级结构主要由不规则卷曲构成,二、三级结构预测结果一致。Snail2基因启动子区序列分析发现1个CpG岛及E2F、C/EBPα(CCAAT/enhancer binding proteins alpha)、AP2和Sp1等与脂肪生成相关的转录因子结合位点。实时荧光定量PCR结果显示,Snail2基因在牛脂肪组织中呈现较高表达水平,且随着脂肪细胞成脂分化和牛生长发育过程均呈现上升趋势,表明Snail2基因在牛脂肪沉积过程中发挥重要作用。研究结果为进一步揭示Snail2基因通过影响脂肪细胞增殖和分化进而影响肉牛脂肪沉积作用机制奠定基础。  相似文献   

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