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Genomic analyses of bovine viral diarrhea viruses isolated from cattle imported into Japan between 1991 and 2005 总被引：2，自引：0，他引：2
Yamamoto T Kozasa T Aoki H Sekiguchi H Morino S Nakamura S 《Veterinary microbiology》2008,127(3-4):386-391
Thirty-one isolates of bovine viral diarrhea virus (BVDV) isolated within the past 15 years from imported cattle by the Japanese Animal Quarantine Service (AQS) were used in this study in which a 5'-untranslated region of each isolate was genetically analyzed. Twenty-six of the 31 isolates were classified as BVDV1 and the remainder as BVDV2. Phylogenetic analysis of the RT-PCR fragments amplified from the isolates showed the presence of viruses belonging to the BVDV1a, BVDV1b, BVDV1c, unclassified BVDV1 genotypes, and BVDV2. From the cattle of Australian origin, 16 of 17 isolates were classified as BVDV1c. This result was in agreement with a report showing that BVDV1c was a predominant subgenotype in Australia. From the cattle of North American origin, BVDV1 and BVDV2 species were both found. BVDV2 from the North American cattle was identified as the same cluster as the BVDV 890 strain, which is the prototype of BVDV2. These results suggest that the BVDVs isolated from exported cattle at the AQS reflect the predominant genotypes of BVDVs found in the exporting countries. The unclassified BVDV1 genotype of Chinese origin was in the same cluster as the ZM-95 strain, which was isolated from pigs in China. In this study, the genomic properties of 31 isolates of BVDV collected in the AQS were investigated. We concluded that isolates are genetically heterogeneous but geographically restricted. The information obtained from this report will be useful when carrying out epidemiological surveys of BVDV isolated in Japan. 相似文献
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P H Walz J C Baker T P Mullaney J B Kaneene R K Maes 《Canadian journal of veterinary research》1999,63(2):119-123
Some isolates of type II bovine viral diarrhea virus (BVDV) are capable of causing severe clinical disease in cattle. Bovine viral diarrhea virus infection has been reported in pigs, but the ability of these more virulent isolates of type II BVDV to induce severe clinical disease in pigs is unknown. It was our objective to compare clinical, virologic, and pathologic findings between type I and type II BVDV infection in pigs. Noninfected control and BVDV-infected 2-month-old pigs were used. A noncytopathic type I and a noncytopathic type II BVDV isolate were chosen for evaluation in feeder age swine based upon preliminary in vitro and in vivo experiments. A dose titration study was performed using 4 groups of 4 pigs for each viral isolate. The groups were inoculated intranasally with either sham (control), 10(3), 10(5), or 10(7) TCID50 of virus. The pigs were examined daily and clinical findings were recorded. Antemortem and postmortem samples were collected for virus isolation. Neither the type I nor type II BVDV isolates resulted in clinical signs of disease in pigs. Bovine viral diarrhea virus was isolated from antemortem and postmortem samples from groups of pigs receiving the 10(5) and the 10(7) TCID50 dose of the type I BVDV isolate. In contrast, BVDV was only isolated from postmortem samples in the group of pigs receiving the 10(7) TCID50 dose of the type II BVDV isolate. Type I BVDV was able to establish infection in pigs at lower doses by intranasal instillation than type II BVDV. Infection of pigs with a type II isolate of BVDV known to cause severe disease in calves did not result in clinically apparent disease in pigs. 相似文献
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Kelling CL Steffen DJ Topliff CL Eskridge KM Donis RO Higuchi DS 《American journal of veterinary research》2002,63(10):1379-1384
OBJECTIVE: To determine the comparative virulence of 5 isolates of bovine viral diarrhea virus (BVDV) type II by inoculating 6- to 9-month-old beef calves with isolates originating from the tissues of cattle affected with naturally occurring, transient, acute, nonfatal infections or naturally occurring, peracute, fatal infections. ANIMALS: 22 calves that were 6 to 9 months old. PROCEDURE: The study used BVDV isolates 17011, 713, and 5521 that originated from fetuses aborted from cows with transient, nonfatal, acute BVDV infections and isolates 23025 and 17583 that originated from the tissues of cattle with peracute, fatal BVDV infections. Calves were allotted to 6 groups (1, mock-infected control calves [n = 2]; 2, inoculated with BVDV 17011 [4]; 3, inoculated with BVDV 713 [4]; 4, inoculated with BVDV 5521 [4]; 5, inoculated with BVDV 23025 [4]; and 6, inoculated with BVDV 17583 [41]. Rectal temperatures and clinical signs of disease were recorded daily. Total and differential WBC and platelet counts were performed. Histologic examination and immunohistochemical analysis were conducted to detect lesions and distribution of viral antigens, respectively. RESULTS: Calves inoculated with BVDV 23025 or 17583 developed more severe clinical signs of disease (fever and diarrhea), more severe lymphopenia, and more severe lesions (alimentary epithelial necrosis, lymphoid depletion, and BVDV antigen deposition in lymphatic tissues), compared with calves inoculated with BVDV 713, 5521, or 17011. CONCLUSIONS AND CLINICAL RELEVANCE: Relative severity of experimentally induced infections corresponded to severity of clinical signs of naturally occurring infections with respective BVDV isolates. 相似文献
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Retrospective analyses of cases from which bovine viral diarrhea virus (BVDV) was isolated from 1980 to 2000 were conducted. These cases originated from the northwestern US and included both beef and dairy cattle. The results indicated that there was a shift in diseases associated with BVDV infection and in the animal age at onset of disease. Comparative results from the 1980 data indicated a low fetal infection rate (<5%), followed by steady increases of clinical cases and peaking at 6 months (30%). By 2000, the shift of BVDV cases was noticeable and indicated a biphasic occurrence of disease. The first phase was fetal infections, which increased to >25%, followed by a second phase at 6 months (>35%). Phylogenetic analysis was conducted on selected isolates from the time period 1998-2000 (n = 54). There were representative viral isolates from the two genotypes (BVDV1 and BVDV2), as well as subgenotypes, BVDV1a and BVDV1b. The types were further correlated with the clinical manifestation, which were reported as mucosal disease, persistently infected (PI)-poor doer, and abortion-open cows. The results indicated that BVDV were distributed throughout the clinical spectrum of disease, with BVDV2 representing the greatest frequency of isolation, and the greatest association with abortion-open cows. When the BVDV genotypes and subgenotypes were categorized into early (<100 days gestation) versus late (>100 days gestation) fetal infections, there was an inverse relationship noted. It was observed that BVDV1a was associated least with early infection (14%) and most with late infections (86%). BVDV1b was intermediate, followed by BVDV2, which was associated more with early infections (45%) and less with late infections (55%) when compared with BVDV1a and BVDV1b. 相似文献
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Platelet aggregation responses and virus isolation from platelets in calves experimentally infected with type I or type II bovine viral diarrhea virus. 
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下载免费PDF全文 P H Walz T G Bell D L Grooms L Kaiser R K Maes J C Baker 《Canadian journal of veterinary research》2001,65(4):241-247
Altered platelet function has been reported in calves experimentally infected with type II bovine viral diarrhea virus (BVDV). The purpose of the present study was to further evaluate the ability of BVDV isolates to alter platelet function and to examine for the presence of a virus-platelet interaction during BVDV infection. Colostrum-deprived Holstein calves were obtained immediately after birth, housed in isolation, and assigned to 1 of 4 groups (1 control and 3 treatment groups). Control calves (n = 4) were sham inoculated, while calves in the infected groups (n = 4 for each group) were inoculated by intranasal instillation with 10(7) TCID50 of either BVDV 890 (type II), BVDV 7937 (type II), or BVDV TGAN (type I). Whole blood was collected prior to inoculation (day 0) and on days 4, 6, 8, 10, and 12 after inoculation for platelet function testing by optical aggregometry by using adenosine diphosphate and platelet activating factor. The maximum percentage aggregation and the slope of the aggregation curve decreased over time in BVDV-infected calves; however, statistically significant differences (Freidman repeated measures ANOVA on ranks, P < 0.05) were only observed in calves infected with the type II BVDV isolates. Bovine viral diarrhea virus was not isolated from control calves, but was isolated from all calves infected with both type II BVDV isolates from days 4 through 12 after inoculation. In calves infected with type I BVDV, virus was isolated from 1 of 4 calves on days 4 and 12 after inoculation and from all calves on days 6 and 8 after inoculation. Altered platelet function was observed in calves infected with both type II BVDV isolates, but was not observed in calves infected with type I BVDV. Altered platelet function may be important as a difference in virulence between type I and type II BVDV infection. 相似文献
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Wakeley PR Turner JL Ibata G King DP Sandvik T Howard P Drew TW 《Veterinary microbiology》2004,102(1-2):19-24
Two genotypes of bovine viral diarrhoea virus (BVDV) are recognised. Type 2 was first recognised when virulent strains caused significant losses among cattle in North America. Subsequently, BVDV type 2 has been found in many other countries, but recent studies have shown that only type 1 BVDV is circulating in the UK herds (sheep and cattle) with type 1a predominating. During routine genotyping of UK BVDV isolates, a type 2 isolate was identified. Phylogenetic analysis of the 5'-untranslated region of the viral genome showed it to be a BVDV type 2a, most similar to a low virulent US strain of BVDV type 2. Antigenic typing with a panel of monoclonal antibodies verified this classification. This is the first confirmed isolation of BVDV type 2 found circulating in the UK. 相似文献
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An inactivated vaccine containing BVDV I and II strains (PT810; BVDV I, and 890; BVDV II) and using different adjuvants and antigen dosages was tested in a cattle challenge model. Groups of six healthy, seronegative cattle were vaccinated twice with a low dose (10(6.6) TCID(50) PT810 and 10(7.2) TCID(50) 890) vaccine with the adjuvant Bay R1005 or a high dose (10(7.8) TCID(50) PT810 and 10(8. 2) TCID(50) 890) vaccine with two different adjuvants (Bay R1005 or Polygen). Thirty-eight days after the second vaccination, immunised animals (n=18) and non-vaccinated control animals (n=3) were challenged intranasally with 10(6) TCID(50) BVDV strain PT810. For a period of 16 days, virus was isolated from blood leukocytes and nasal swabs, and neutralising antibody titres were determined.The induction of antibodies following immunisation was strongly dependent on the antigen dosage in the vaccine. The high dose formulation induced high serum neutralising antibody titres against both genotypes of up to 32000 after the second immunisation. Animals with neutralising antibody titres >512 (n=14) did not show any marked leukopenia after challenge and only very little or no virus could be isolated from blood leukocytes and/or nasal swabs when compared to control cattle. Furthermore, some of these animals did not show any boost of neutralising or even NS3-specific antibodies, which renders viral replication unlikely and thus would prevent infection of the fetus. Both adjuvants (Bay R1005 or Polygen) were similarly efficient and induced nearly identical antibody responses. In contrast, four of the six low dosage vaccinates had a marked leukopenia and viraemia as well as detectable nasal virus shedding for several days.We conclude that the selected strains and the system of vaccine preparation with high BVDV antigen dosages and highly efficient new adjuvants provide an effective means of protection against BVDV I infections. Investigations to demonstrate the protection against BVDV II infections, the duration of immunity and the ability of fetal protection by using the high dose vaccine in a fetal challenge model will follow. 相似文献
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Virus neutralising antibodies against 22 bovine viral diarrhoea virus isolates in vaccinated calves.
C Hamers E Di Valentin C Lecomte M Lambot E Joris B Genicot P-P Pastoret 《Veterinary journal (London, England : 1997)》2002,163(1):61-67
Seven of nine colostrum deprived calves, free from bovine viral diarrhoea virus (BVDV), were vaccinated with a commercially available vaccine containing two inactivated strains of BVDV, an inactivated strain of bovine herpesvirus-1 and modified-live strains of bovine respiratory syncytial virus and para-influenza-3 virus. The two other calves were kept as controls. The virus neutralising (VN) antibodies induced by vaccination were tested against 22 antigenically diverse BVDV isolates, including reference strains and field isolates, both cytopathic and non-cytopathic, as well as genotypes I and II. The strains were isolated in Belgium, France, Germany, the United Kingdom and the USA. While there were variations in the VN titres of the individual calves against all the strains, serum from the seven animals neutralised 20 or more of the strains tested. From the results, it can be concluded that the vaccine can stimulate the production of VN antibodies capable of neutralising a wide range of European and American isolates of BVDV, including genotypes I and II. 相似文献
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Fulton RW Ridpath JF Ore S Confer AW Saliki JT Burge LJ Payton ME 《Veterinary microbiology》2005,111(1-2):35-40
The prevalence of bovine viral diarrhoea virus (BVDV) biotypes and subgenotypes was determined from 131 BVDV positive samples from a diagnostic laboratory. The majority of the isolates were from Oklahoma; however, other states including Kansas, Texas, and Arkansas were represented. These BVDV samples were from submissions of 76 live animals and 55 necropsy samples. There were 131 BVDV samples represented by 117 noncytopathic (NCP), 11 cytopathic (CP) and 3 cases with mixed NCP and CP biotypes. The NCP isolates were more common (P < 0.05) than the CP and NCP/CP combination. The BVDV samples were segregated into three subgenotypes by differential PCR and sequencing of a viral genomic region, 5'-untranslated region (5'-UTR). There were more BVDV1b subgenotypes 60/131 (45.8%) than BVDV1a, 37/131 (28.2%) or BVDV2a, 34/131 (26.0%) (P < 0.05). The organ system involvement included the major categories such as respiratory, digestive, mixed/multiple organs, abortions, and persistent infections (PI). All three BVDV subgenotypes were found in persistently infected (PI) cattle and respiratory diseases, both major requests for BVDV diagnosis. Only one of the 131 viruses was genetically similar to the strains present in U.S. vaccines. 相似文献
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Using RNA purified directly from stored clinical specimens, a collection of 62 pestiviruses were typed by RT-PCR and sequencing within the 5'-untranslated region of the genome. All the specimens had been obtained in 1966/1967 from diary cattle in England and Wales. Eight further pestiviruses, grown in cell culture, were characterised in the same way. Seven of these viruses were representatives of a panel of British isolates, obtained from cattle ten years before. The eighth was the virus used in a British bovine viral diarrhoea (BVD) vaccine. Most of the viruses were genetically unique and were of BVDV type Ia. One recent isolate was BVDV type Ib, two others were intermediate between Ia and Ib. No BVDV type II or border disease virus (BDV) isolates were found. There was no overall association between geographical and phylogenetic clustering, suggesting long-distance virus dispersal, presumably via trading of infected cattle. The sequences of the recently obtained cattle viruses were very similar or, in one case, identical to the older isolates in the region studied. Their close similarity to some previously characterised pestiviruses from British sheep suggests that a common pool of BVDV Ia is shared by these two livestock species, although another pestivirus--BVDV--is confined to sheep. The British cattle viruses were mostly distinct from continental European isolates, but more similar to type Ia isolates from North American cattle. 相似文献
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A selection of 43 bovine viral diarrhoea viruses isolated from mainly persistently infected cattle on 23 Slovenian farms between 1997 and 2001 were characterised genetically. Viral RNA was extracted from infected cell cultures, reverse transcribed and amplified by PCR with primers targeting the 5'-UTR and the N(pro) gene, followed by direct sequencing of purified PCR products obtained for both genomic regions. The N(pro) sequences provided the best genetic resolution, and gave also higher statistical support for phylogenetic classification of the viruses. Thirty-eight of the Slovenian isolates were of genetic subtypes 1d and 1f, four were 1b, and one subtype 1g. No BVDV type 2 viruses were found. This genetic prevalence matched those previously reported for neighbouring countries, as opposed to findings reported for more distant European countries, e.g. France, Spain and the UK. From eight cattle herds several virus isolates were analysed; with one exception all isolates from each herd were of the same genetic group. Extended sequencing of the N(pro) and part of the C gene of virus isolates with identical 5'-UTR sequences allowed differentiation between isolates obtained at different times from one herd. 相似文献
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A method to evaluate the efficacy of bovine viral diarrhea virus (BVDV) vaccines using a multiple challenge model was investigated. Four pregnant heifers were challenged intranasally with a type I and type II isolate of BVDV at 75 days of gestation. At 60 days postinoculation, virus isolation and RT-PCR from blood and tissues of fetuses indicated that all fetus were persistently infected with both type I and type II isolates. Differing results of detection by PCR and virus isolation between the type I and type II isolates were obtained. These preliminary studies may indicate differences in the level of replication between type I and type II BVDV as well as predilected sites of replication in certain tissues. 相似文献
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Vilcek S Durkovic B Kolesarova M Paton DJ 《Preventive veterinary medicine》2005,72(1-2):31-5; discussion 215-9
Genetic typing of bovine viral diarrhoea virus (BVDV) is important for the precise classification of viruses as well as for the development of molecular epidemiology. BVDV isolates were usually typed based on comparison of genomic sequences from the 5'-untranslated region (5'-UTR), N(pro) and E2 region. Recently we have identified 11 genetic groups (subgenotypes) of BVDV-1. Our further experiments confirmed a new subgenotype, BVDV-1k, isolated from cattle in Switzerland. BVDV isolates from India were typed as BVDV-1b whereas BVDV-1c is a predominant subgenotype in Australia. The results of genetic typing of BVDV indicate that distribution of subgenotypes has no relationship to the geographic origin of viral isolates. 相似文献
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Phylogenetic, antigenic and clinical characterization of type 2 BVDV from North America 总被引：1，自引：0，他引：1
Bovine viral diarrhea virus (BVDV) infection continues to have a significant impact upon US cattle producers despite the availability of more than 140 federally licensed vaccines. Detection and control is hampered by viral heterogeneity that results in differences in neutralizing epitopes, cytopathology and virulence. Recently it was found that there are two different genotypes, BVDV1 and BVDV2, among BVDV. BVDV2 isolates make up a significant proportion of the BVDV isolated in North America. Serologically BVDV2 viruses can be distinguished from BVDV1 and border disease viruses. Mab binding also distinguishes between BVDV1, BVDV2 and BDV. Like the BVDV1 viruses, BVDV2 viruses may exist as one of two biotypes, cytopathic or noncytopathic, based on their activity in cultured cells. Cytopathogenic effects on cultured cells does not correlate with virulence in vivo, as BVDV2 associated with hemorrhagic syndrome (HS) are noncytopathic. Variation among BVDV1 and BVDV2 in the 5' UTR is similar. Phylogenetic analysis and differences in virulence suggest that BVDV2 are heterogeneous. Symptoms resulting from BVDV2 infections may range from clinically inapparent to clinically severe. Recently, disease outbreaks associated with acute uncomplicated BVDV infection have been reported in the US and Canada. These outbreaks of clinically severe disease, termed HS, were all associated with viruses from the BVDV2 genotype. Not all BVDV2 isolates cause clinically severe disease. Avirulent BVDV2 isolates do exist and may predominate over virulent BVDV2 in nature. When virulent BVDV2 viruses are inoculated into calves they induce a disease characterized by fever, diarrhea, leukopenia, lymphopenia, neutropenia, thrombocytopenia, and death. Infection with avirulent BVDV2 results in a reduction of luekocytes that may be accompanied by a low-grade fever. These viruses do not cause clinical disease or a clinical leukopenia. 相似文献
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AIM: To investigate the genetic type of 20 pestiviruses collected from New Zealand over the period 1967-97. METHODS: The pestiviruses were genetically typed by the sequencing of polymerase chain reaction (PCR) products. The primers selected were from the 5'-untranslated region (5'-UTR) of the pestivirus genome and consistently amplified a 288 bp fragment from all samples tested. RESULTS: Sequencing and phylogenetic analysis of PCR products revealed that all samples obtained from cattle represented bovine viral diarrhoea (BVDV) type I. Two sheep isolates were characterised as border disease virus (BDV). A pestivirus isolated from foetal calf serum of USA origin was typed as BVDV type II. CONCLUSIONS: The findings show that the evolution of pestiviruses in New Zealand has been similar to Europe and North America, indicating the occurrence of a conservative phylogenetic branch of BVDV type I in cattle and the presence of BDV in the sheep population. 相似文献