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1.
Pestiviruses cause economically important diseases of farm animals. Members of the Pestiviruses are bovine viral diarrhea virus 1 (BVDV-1), BVDV-2, classical swine fever virus (CSFV) and border disease virus (BDV). Phylogenetic analyses based on the entire nucleic acid sequence encoding the Npro allow a statistically significant segregation of established species and of subgroups within the species. BVDV-1 strains isolated in Germany can be associated with at least five different subgroups. In contrast all BVDV-2 isolates detected in Germany so far are closely related, belonging to one subgroup. A group of virus isolates from sheep and zoo animals is clearly different from established pestivirus species and can be designated as BDV-2. Antigenetic relatedness of pestiviruses was studied using defined virus isolates and antisera in cross-neutralization assays. Six antigenic groups were distinguished corresponding to the genetic clusters BVDV-1, BVDV-2, CSFV, BDV-1, BDV-2 and Giraffe-1. A significant antigenic difference was also observed between members of subgroups 1a and 1b of BVDV-1. Studies on the genetic and antigenic heterogeneity of pestiviruses are important for the development of new vaccines, diagnostic tests and for eradication programs.  相似文献   

2.
Pestiviruses isolated from sheep and goats in India thus far have been bovine viral diarrhoea virus 1 (BVDV-1) or BVDV-2. During routine genetic typing of pestiviruses in the years 2009-10, border disease virus (BDV) was detected in eight Indian sheep of a flock showing clinical signs of BD by real time RT-PCR. All the samples yielded positive virus isolates in cell culture but were found negative by a BVDV antigen ELISA. A representative BDV isolate was characterized at genetic and antigenic level. Phylogenetic analysis carried out in 5′-UTR, Npro and E2 regions of genome typed the Indian BDV isolate as BDV-3. A more detailed analysis in Npro and entire region coding structural proteins showed that the Npro (168), C (100 aa), Erns (227 aa), E1 (195 aa) and E2 (373 aa) proteins were of size characteristic for BDV reference strain X818. Antigenic differences were evident between the BDV-3 isolate and previously reported BDV-1, BDV-5 and BDV-7 strains. Although origin of BDV-3 in India is not clear, the results reflect probable introduction through trade in sheep between India and other countries or BDV-3 may be more widely distributed. Additionally, this study suggests that for diagnosis of BDV infection, the commercial BVDV Ag-ELISA should be used with caution. This is the first identification of BDV in sheep in India which highlights the need for continued pestivirus surveillance and assessing its impact on sheep and goat production.  相似文献   

3.
Between 2001 and 2002, samples from 1,413 animals in 21 Spanish small ruminant flocks, most of them with animals showing clinical signs compatible with Border disease (BD), were screened for the presence of Pestivirus antigen and antibodies by an indirect peroxidase monolayer assay (IPMA) and the virus neutralization test (VNT), respectively. Although all flocks harboured seropositive animals, virus could only be isolated from animals in five of the flocks. Between 4 and 11 months later all animals older than 6 months in three of the flocks were resampled. At this time, 51-83% of them had neutralizing antibodies. The prevalence of persistently infected (PI) animals within two of the flocks was 0.3 and 0.6%, respectively. The third flock presumably had eliminated all the PI animals. Fourteen virus isolates were obtained. The 5' untranslated region (5'UTR) was amplified by RT-PCR and directly sequenced. Phylogenetic analyses classified them as a group of Border disease viruses (BDV), separated from BDV-1, but showing a relatively low bootstrap value. Three of the 14 isolates were in the same subgroup as a set of formerly characterised Spanish isolates from the Basque Country, which were allocated to subgroup BDV-C. In addition, they were in the group with an isolate from chamois, which is currently allocated in group BDV-4. Because of its close relation to the chamois isolate, these isolates were tentatively reallocated in a subgroup BDV-4a. The remaining isolates generated a new subgroup, related but not in the same cluster as the chamois isolate, and was therefore tentatively assigned to a new subgroup BDV-4b. Our results show that classification and nomenclature of BDV needs to be harmonised.  相似文献   

4.
1株猪源牛病毒性腹泻病毒的分离与鉴定   总被引：2，自引：1，他引：1  
从BVDV阳性仔猪病料中分离病毒,为开展猪源BVDV病原学研究奠定基础。将处理后BVDV阳性仔猪组织样品接种MDBK细胞,分离到1株猪源BVDV,命名为SD0803株。通过细胞培养、直接免疫荧光、5′-UTR与Npro PCR扩增、电镜观察、TCID50测定及对其分子进化特征加以分析。结果表明,该毒株在MDBK细胞上盲传至13代未出现细胞病变。在直接免疫荧光试验中呈阳性荧光信号。PCR扩增分别获得5′-UTR与Npro预期大小DNA片段。电镜观察,病毒粒子略呈圆形,有囊膜,直径约50nm。病毒滴度为10-6.5 TCID50.0.2 mL-1。SD0803 5′-UTR、Npro序列进化分析显示,该分离株属于BVDV-1,与已知BVDV-1各亚型之间同源性较低,单独成一分支。结果表明,成功分离鉴定1株猪源BVDV SD0803,该毒株为非致病变型BVDV-1,极有可能为BVDV-1新的亚型。  相似文献   

5.
In 2001 a new Pestivirus (Family Flaviviridae) was associated with an outbreak of a previously unreported disease in Pyrenean chamois (Rupicapra pyrenaica) in the Pyrenees (NE Spain). Molecular characterization assigned this virus to the Border Disease Virus (BDV) cluster, BDV-4 genotype. A retrospective study was performed in archived sera and spleen of 74 Pyrenean chamois and in archived sera of 28 mouflon (Ovis ammon), 56 red deer (Cervus elaphus), 43 roe deer (Capreolus capreolus) and 29 fallow deer (Dama dama) from the Pyrenees between the years 1990 and 2000. Thirty six of 74 (48.6%) sera of Pyrenean chamois, one of mouflon and one of red deer were positive by an ELISA antibody test. Comparative virus neutralization tests were performed on 26 seropositive chamois, one mouflon and one red deer, using five pestivirus strains. An ELISA antigen test was performed on 37 seronegative chamois and yielded positive results in one chamois and inconclusive result in two. RT-PCR and virus isolation performed on spleen samples from these three animals gave positive results in the positive and one inconclusive animal. Sequence analysis in the 5' unstranslated region revealed that they were grouped into the BDV-4 genotype. Virological and serological data of the present study indicate that BDV infection has been present in the chamois population since at least 1990, 11 years before the first outbreak of disease. Therefore, the emergence of the disease in 2001 is apparently due to other factors rather than the introduction of a new virus in the chamois population.  相似文献   

6.
In the last decade, several studies were performed to characterise bovine viral diarrhoea virus (BVDV) isolates and define genetic groups by genotyping. Much data is now available from GenBank, predominantly sequences from the 5' untranslated region (5'-UTR). In order to find out whether genetic grouping of isolates from different countries could be harmonised, 22 new isolates from five countries were analysed in combination with published sequences. Eighteen of these isolates were typed as BVDV genotype 1 (BVDV-1), and one isolate from Argentina and three isolates from Brazil were typed as BVDV-2. BVDV-1 isolates were clustered into five previously defined genetic groups: BVDV-1a, b, d, e and f. Two isolates from Finland and one from Egypt formed a group which was tentatively labelled as BVDV-1j, since statistical support was low. By using a fragment of the Npro gene for typing, we found that these isolates fall into the same group as a deer strain, and are statistically significant. Some Swiss BVDV strains taken from GenBank were found in a new genetic group which was designated as BVDV-1k. The BVDV-2 isolates included in this study seemed to fall into two genetic groups.  相似文献   

7.
In 2001 and 2002, an outbreak of a previously unreported disease, associated with a border disease virus (BDV), caused high mortality in the Southern chamois (Rupicapra pyrenaica) population in the Alt Pallars-Aran National Hunting Reserve in the Catalan Pyrenees (NE Spain). Between 2002 and 2006, sera and/or tissue samples taken from 116 healthy chamois shot during the hunting season, plus 42 from chamois affected by different diseases, were studied. A blocking enzyme-immunosorbent assay (ELISA) was used to study pestivirus seroprevalence in 114 healthy hunted and 31 diseased chamois, yielding positive results in 73.7 and 22.6% of the chamois, respectively. Comparative virus neutralization tests (VNT) performed on 42 seropositive samples with 6 pestivirus strains yielded statistically higher titres to BDV Spain 97, followed by BDV chamois, BDV 137/4, BDV Moredun, Bovine Diarrhoea virus-1 (BVDV-1) NADL and BVDV-2 atypical. Virological investigations for pestivirus detection were performed using an antigen ELISA test in 82 healthy and 18 diseased chamois, RT-PCR in 16 healthy and in all diseased chamois, and virus isolation in 14 diseased chamois. No viral antigen was detected in any of the healthy animals. A pestivirus, characterized as BDV by monoclonal antibodies, was detected in the 10 chamois showing clinical signs consistent with BDV infection. Sequence analysis in the 5' untranslated region (5'-UTR) revealed that they were grouped into the BDV-4 genotype. In the remaining chamois, infectious keratoconjunctivitis, pneumonia, trauma and contagious ecthyma were diagnosed. The cause of death was unknown in five chamois. The results suggest that the infection has become endemic in the population and that it could have a significant impact on chamois population dynamics.  相似文献   

8.
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9.
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10.
Genetic heterogeneity of Turkish ruminant pestiviruses was investigated by phylogenetic analysis of complete N(pro) encoding nucleotide sequences. A total of 30 virus isolates obtained from 15 provinces around the country between 1997 and 2005 were included in the phylogenetic analysis. Virus isolates mostly originated from cattle with one isolate from sheep. The bovine isolates all belonged to BVDV-1, the sheep isolate to BVDV-2. Fifteen isolates formed a new subgroup within BVDV-1, tentatively named BVDV-1l. The remaining bovine isolates were typed as BVDV-1a (n=4), BVDV-1b (n=4), BVDV-1d (n=3), BVDV-1f (n=2) and BVDV-1h (n=1). The isolates allocated to BVDV-1l originated from various geographical regions in different years. There was no correlation between genetic grouping and locations where isolates were obtained. Viruses originating from one farm in most cases belonged to the same subgroup (n=5). This study indicates that the newly detected subgroup BVDV-1l is predominant and widespread in Turkey. Moreover, an ovine virus isolate was identified as the first member of BVDV-2 reported in Turkey. A serological survey using samples from western Turkey indicated that BVDV-2 is also present in cattle.  相似文献   

11.
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12.
Bovine viral diarrhea virus 2 (BVDV-2) strains demonstrated in cattle, sheep, and adventitious contaminants of biological products have been evaluated by the palindromic nucleotide substitutions (PNS) method at the three variable loci (V1, V2 and V3) in the 5' untranslated region (UTR), to determine their taxonomical status. Variation in conserved genomic sequences was used as parameter for epidemiological evaluation of the species in relation with geographical distribution, animal host and virulence. Four genotypes, BVDV-2a, BVDV-2b, BVDV-2c, and BVDV-2d have been identified within the species. Taxonomical segregation corresponded to geographical distribution of genotype variants. Genotype 2a was present worldwide, and was the only circulating also in sheep, in addition to cattle. Genotypes 2b, 2c and 2d were restricted to South America. Contamination of biological products was related to genotypes 2a and 2d. Genetic variation could be related with chronological diffusion of the BVDV-2 species variants in different geographic areas. Chronologically, the species emerged in North America in 1978, spreading in UK and Japan, continental Europe, South America and New Zealand. Correlation between clinical features related with isolation of BVDV-2 strains and genetic variation indicated that subgenotype 1, variant 4 of genotype 2a was related with hemorrhagic syndrome. These observations suggest that evaluation of genomic secondary structure, by identifying markers for expression of virus biological activities and species evolutionary history, may be applied as useful tool for epidemiological evaluation of the BVDV-2 species, and possibly for other species of the genus Pestivirus.  相似文献   

13.
The Pestivirus genus within the family of Flaviviridae consists of at least three species; classical swine fever virus (CSFV) found in swine and wild boar, bovine viral diarrhoea virus type 1 and type 2 (BVDV-I and BVDV-II) mainly isolated from cattle and border disease virus (BDV) preferably replicating in ovine species. Many features demonstrate differences between CSFV and other pestiviruses, BVDV-I, BVDV-II and BDV, here defined as nonCSFV, whereas other features show similarities between all different species of pestiviruses. Focussing on the major envelope glycoprotein E2, the immunodominant protein of pestiviruses, CSFV seems to be a more distinct species within the Pestivirus genus. Here we confirm on one hand the more separated grouping of CSFV by isolation of monoclonal antibodies (MAbs) raised against E2 of BVDV-I and BVDV-II. None of these MAbs recognize E2 of CSFV strains. On the other hand, only one MAb, MAb 912, was isolated against E2 of BDV. MAb 912 binds to E2 of CSFV strains and partly neutralizes CSFV. The epitope of MAb 912 is mapped in antigenic domain B of CSFV-E2. This common epitope of CSFV strains and nonCSFV strains could have implications for development of DIVA vaccines and serological diagnostics for CSF.  相似文献   

14.
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15.
The prevalence of antibodies to pestiviruses was investigated in 4931 sheep, in 377 flocks, in four federal states of Austria, by means of an indirect elisa that detected antibodies to Border disease virus (BDV) and bovine viral diarrhoea virus (BVDV). The mean flock prevalence was 62.9 per cent and the mean individual prevalence was 29.4 per cent. Comparative neutralisation studies on the elisa-positive samples with BVDV type 1 (BVDV-1), BVDV type 2 (BVDV-2) and BDV recorded 336 samples with higher titres (more than four times average) to BVDV-1, three samples with higher titres to BVDV-2 and 55 samples with higher titres to BDV. The other samples did not show clear differences in antibody titres against the strains of pestivirus tested because of cross-reactions. The seroprevalence of pestiviruses in sheep was significantly higher on farms with cattle. There were significant regional differences between the prevalences in flocks and individual sheep, the highest prevalences being in the region of Austria where communal alpine pasturing of sheep, goats and cattle is an important part of farming.  相似文献   

16.
Pestiviruses are capable of infecting a wide range of animals within the order Artyodactila. Currently, the genus Pestivirus includes Bovine Viral Diarrhea Virus 1 (BVDV-1) and 2 (BVDV-2), Border Disease Virus (BDV), and Classical Swine Fever Virus (CSFV). BVDV-1, BVDV-2 and BDV are able to cross species barrier to infect a wide range of hosts, whereas CSFV is restricted to domestic pigs and wild boars. In Argentina, 70% of cattle are seropositive to BVDV. Although there were some serological studies in llamas, alpacas and buffaloes, no reports existed about the circulation of BVDV in sheep in Argentina. Based on these, 54 blood samples of healthy ovines were analysed by serology. The results showed that 46.3% of the analysed sheep were seropositive to BVDV-1, 13% to BVDV-2 and 20.4% for both BVDV-1 and BVDV-2. The molecular analysis confirmed the presence of BVDV-1a in some samples.  相似文献   

17.
Previous studies have shown that bovine viral diarrhoea virus type 1 (BVDV-1) subtype b is predominantly circulating in Indian cattle. During testing for exotic pestiviruses between 2007 and 2010, BVDV-2 was identified by real time RT-PCR in two of 1446 cattle blood samples originating from thirteen states of India. The genetic analysis of the isolated virus in 5′ UTR, Npro, entire structural genes (C, Erns, E1 and E2), nonstructural genes NS2-3 besides 3′ UTR demonstrated that the nucleotide and amino acid sequences showed highest similarity with BVDV-2. The entire 5′ and 3′ UTR consisted of 387 and 204 nucleotides, respectively, and an eight nucleotide repeat motif was found twice within the variable part of 3′ UTR that may be considered as a characteristic of BVDV-2. The phylogenetic analysis revealed that the cattle isolate and earlier reported goat BVDV-2 isolate fall into separate clades within BVDV-2a subtype. Antigenic typing with monoclonal antibodies verified the cattle isolate also as BVDV-2. In addition, cross-neutralization tests using antisera raised against Indian BVDV strains circulating in ruminants (cattle, sheep, goat and yak) displayed significant antigenic differences only between BVDV-1 and BVDV-2 strains. This is the first identification of BVDV-2 in Indian cattle that may have important implications for immunization strategies and molecular epidemiology of BVD.  相似文献   

18.
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19.
Since cattle are widely infected by bovine viral diarrhea virus (BVDV) in India, we searched for pestivirus infection in yaks. Of 71 pure and crossbred yaks from Himalayan region, pestivirus antigen was detected by Ag-ELISA in three animals. Pestivirus in leukocyte and cell culture isolated virus samples originating from positive yaks was also confirmed by RT-PCR using panpestivirus specific primers selected from 5'-untranslated region (5' UTR). The 5' UTR, N(pro) and E2 regions were sequenced and used for genetic typing. Phylogenetic analysis revealed that pestiviruses detected in three Himalayan yaks were similar genetically, belonging to BVDV-1. Antigenic characterisation of yak pestivirus also confirmed the typing as BVDV-1. This is the first report on the identification of BVDV type 1 in yaks.  相似文献   

20.
Serological investigations were carried out to determine the prevalence of pestiviral infections in goats in Austria, and to investigate the possible relations to herd management practices. The prevalence of antibodies to pestiviruses was investigated in 549 goats in 80 flocks from four regions of Austria. The examination for antibodies was performed using an indirect enzyme-linked immunosorbent assay detecting antibodies to the border disease virus (BDV) and bovine viral diarrhoea virus (BVDV). The observed individual prevalence was 11.5% and the flock prevalence was 31.3%. Comparative neutralization studies on the 63 seropositive samples with BVDV-1, BVDV-2 and the BDV yielded in 32 samples higher titres (> or =4-fold) to BVDV-1 and in two samples to BDV. The remaining samples did not show distinct differences in antibody titres against the pestivirus strains tested because of the cross-reactions. There was a significant (P < 0.05) association between the prevalence of antibodies to pestiviruses and the presence of cattle on the farm. Significant (P < 0.05) geographical variations in individual prevalence were obtained, ranging from 3.5% in lower Austria to 20.2% in Vorarlberg.  相似文献   

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