Publications
| Title | Abstract | Year(sorted descending) Filter | PMID Filter |
|---|
| lesions and distribution of viral antigen following an experimental infection of young seronegative calves with virulent bovine virus diarrhea virus-type ii. | during the past several years, acute infections with bovine viral diarrhea virus (bvdv) have been causally linked to hemorrhagic and acute mucosal disease-like syndromes with high mortality. the majority of bvdvs isolated in such cases have been classified as type ii on the basis of genetic and antigenic characteristics. it was our objective to examine clinical disease, lesions and potential sites of viral replication, following experimental bvdv type ii infection in young calves. on approximate ... | 1998 | 9684044 |
| immunohistochemical evidence for the localization of bovine viral diarrhea virus, a single-stranded rna virus, in ovarian oocytes in the cow. | bovine viral diarrhea virus (bvdv) is a single-stranded rna virus responsible for enteric disease and reproductive failure in cattle. the virus can pass vertically from cow to fetus, causing abortion, birth of malformed calves, and calves born with persistent and life-long infections. in this study, we investigated the tropism of bvdv in ovarian tissue from persistently infected animals. three heifers persistently infected with bvdv were euthanatized and their ovaries were recovered. a specimen ... | 1998 | 9684968 |
| border disease of sheep and goats. | border disease (bd) is a congenital virus disease of sheep and goats first reported in 1959 from the border region of england and wales. bd virus (bdv) is a pestivirus in the genus flaviviridae and is closely related to classical swine fever virus and bovine virus diarrhoea virus (bvdv). nearly all isolates of bdv are non-cytopathogenic (ncp) in cell culture. there are no defined serotypes but pestiviruses isolated from sheep exhibit considerable antigenic diversity and three distinct antigenic ... | 1998 | 9689745 |
| epidemiologic herd-level assessment of causative agents and risk factors for winter dysentery in dairy cattle. | to test the association between exposure to bovine coronavirus (bcv) and outbreaks of winter dysentery (wd) in dairy herds and to examine other risk factors for outbreaks of wd in dairy herds. | 1998 | 9706203 |
| detection of bovine viral diarrhea virus (bvdv) using reverse transcription polymerase chain reaction assay. | the reverse transcription polymerase chain reaction (rt-pcr) was applied to detect bovine viral diarrhea virus (bvdv) for the rapid diagnosis. the primers were selected from the p80 region of bvdv gene. the rt-pcr assay detected all of the 17 bvdv strains tested including cytopathogenic and non-cytopathogenic strains, while specific amplification was not observed from 17 bovine viruses other than bvdv. detection limit of the assay was 10(1.5) tcid50/ml. sera and organ samples were collected from ... | 1998 | 9713819 |
| critical factors affecting the diagnostic reliability of enzyme-linked immunosorbent assay formats. | this paper aims to evaluate different formats of the enzyme-linked immunosorbent assays (elisas) for detection of virus-specific antibodies and focuses on factors that may influence the diagnostic reliability of such tests. newly developed and well-established elisas for detection of infections of bovine herpesvirus 1 (bhv1), bovine respiratory syncytial virus (brsv), classical swine fever virus (csfv), pseudorabies virus (prv) and bovine viral diarrhoea virus (bvdv) are used as examples. differ ... | 1998 | 9713894 |
| prevalence of antibodies to bovine viral diarrhoea virus and/or border disease virus in domestic ruminants. | a total of 62 sera collected from cattle, buffalo, sheep, goats and camels were investigated for the presence of antibodies to bovine viral diarrhoea (bvd) virus. the prevalence of neutralizing antibodies to bvd virus was 49.2, 52.0, 27.5, 31.4 and 52.5% in cattle, buffalo, sheep, goats and camels, respectively. the positive sera were titrated against bvd virus (bvdv) strains nadl and oregon c24v; the latter is closely related to border disease (bd) virus. the frequency distributions of the anti ... | 1998 | 9719767 |
| long-term viral serology of semi-free-living and captive ungulates. | between 1973 and 1994, blood samples were collected at whipsnade wild animal park (uk) from three ungulate species kept in enclosures, including 28 european bison (bison bonasus), 37 scimitar-horned oryx (oryx dammah), and 49 père david's deer (elaphurus davidianus), and also from 144 semi-free-living chinese water deer (hydropotes inermis). these samples were tested for the presence of antibodies against three bovine viral diarrhea virus (bvdv)-like strains, three alpha-herpesvirus strains, enz ... | 1998 | 9732031 |
| pathogenesis of mucosal disease, a deadly disease of cattle caused by a pestivirus. | two biotypes of pestiviruses, cytopathogenic (cp) and non-cytopathogenic (noncp) viruses, are distinguished by their effects on tissue culture cells. in contrast to the bovine viral diarrhoea virus (bvdv) system, only a few cp border disease virus (bdv) and cp classical swine fever virus (csfv) strains have been described. antigenically closely related noncp and cp bvdv can be isolated from cattle with fatal mucosal disease (md) and are called a virus pair. the generation of cp bvdv in an animal ... | 1998 | 9741637 |
| maternal recognition of foetal infection with bovine virus diarrhoea virus (bvdv)--the bovine pestivirus. | pestiviruses are the veterinary viruses with genome homology to human hepatitis c virus (hcv). this group includes classical swine fever virus (csfv), border disease virus of sheep (bdv) and bovine virus diarrhoea virus (bvdv). there are some similarities in the pathology of all three virus infections; in utero transmission to the foetus can cause early embryonic losses, severe congenital abnormalities and, particularly with bvdv, lifelong persistent infections. in situ hybridisation studies hav ... | 1998 | 9741639 |
| influence of concurrent bvdv infection on the igm response of calves experimentally infected with bovine respiratory syncytial virus. | 1998 | 9762762 | |
| ribosomal s27a coding sequences upstream of ubiquitin coding sequences in the genome of a pestivirus. | molecular characterization of cytopathogenic (cp) bovine viral diarrhea virus (bvdv) strain cp rit, a temperature-sensitive strain widely used for vaccination, revealed that the viral genomic rna is about 15.2 kb long, which is about 2.9 kb longer than the one of noncytopathogenic (noncp) bvdv strains. molecular cloning and nucleotide sequencing of parts of the genome resulted in the identification of a duplication of the genomic region encoding nonstructural proteins ns3, ns4a, and part of ns4b ... | 1998 | 9765411 |
| identification and characterization of an rna-dependent rna polymerase activity within the nonstructural protein 5b region of bovine viral diarrhea virus. | nonstructural protein 5b (ns5b) of bovine viral diarrhea virus (bvdv) contains sequence motifs that are predictive of an rna-dependent rna polymerase activity. we describe the expression and purification of the bvdv ns5b protein derived from an infectious cdna clone of bvdv (nadl strain). bvdv ns5b protein was active in an in vitro rna polymerase assay using homopolymeric rna or bvdv minigenomic rna templates. the major product was a covalently linked double-stranded molecule generated by a "cop ... | 1998 | 9765490 |
| virulence markers in the 5' untranslated region of genotype 2 bovine viral diarrhea virus isolates. | virulence markers to distinguish high from low virulence bovine viral diarrhea virus genotype 2 isolates have not been previously reported. the objective of this study was to identify virulence markers by evaluating the primary and secondary structures of the 5'-untranslated region of low and high virulence bovine viral diarrhea virus genotype 2 isolates. the nucleotide sequences of the entire 5'-untranslated region mrna of eight bovine viral diarrhea virus genotype 2 isolates, four of high viru ... | 1998 | 9770430 |
| an rt-pcr assay for the specific detection of classical swine fever virus in clinical samples. | a simple reverse transcriptase-polymerase chain reaction (rt-pcr) assay has been developed for the specific amplification of dna after reverse transcription of rna from the classical swine fever virus (csfv). a pair of oligonucleotides was selected from an area of high homology in the genome of csfv strains, but which differed from the corresponding sequences in the genome of bovine viral diarrhea virus (bvdv) strains. using these primers (csfv1-csfv2), a csfv specific dna band of 174 bp was amp ... | 1998 | 9779556 |
| an experimental study of a concurrent primary infection with bovine respiratory syncytial virus (brsv) and bovine viral diarrhoea virus (bvdv) in calves. | experimental infections with bovine respiratory syncytial virus (brsv) and bovine viral diarrhoea virus (bvdv) were performed to study the effect of concurrent brsv and bvdv infections. twelve seronegative calves, in 3 groups, were inoculated on a single occasion with pure brsv (group a), brsv and noncytopathogenic bvdv (group b) or mock infected (group c). mild respiratory symptoms were recorded 4 to 5 days post inoculation (dpi) in group a and group b calves. one calf in group a was severely a ... | 1998 | 9787488 |
| [the occurrence of bvd virus infections in lower austrian dairy farms]. | bulk tank milk samples from 5,024 dairy herds in lower austria were tested by elisa for antibodies to bovine virus diarrhoea virus (bvdv). approximately 54 per cent of the herds had a low level of bulk tank antibody unsuspected of recent infection with bvdv. in 512 herds, which had a high level of bulk tank antibody suggestive of recent infection with bvdv, milk samples from 5-10 primiparous cows, respectively were tested by elisa for antibodies to bvdv. in 287 (56.1%) of these 512 herds only an ... | 1998 | 9793236 |
| evaluation of the suitability of a commercial bovine viral diarrhoea virus antigen capture elisa for diagnostic testing. | the suitability of a commercial bovine viral diarrhoea virus (bvdv) antigen capture enzyme-linked immunosorbent assay (elisa) for routine diagnostic testing of bovine serum samples was evaluated by comparing the elisa results of 214 sera with those obtained after two passages in roller tube cultures of fetal bovine lung cells and immunofluorescent staining using fluorescein isothiocyanate-conjugated hyperimmune bvdv anti-serum. in addition, 208 of these samples were tested by virus isolation in ... | 1998 | 9805483 |
| acute pulmonary lesions in sheep experimentally infected with bovine viral diarrhoea virus. | six sheep, aged 6-8 months and seronegative for pestivirus, were inoculated intranasally, through the tracheal wall, and intrabronchially with a non-cytopathogenic isolate of bovine viral diarrhoea virus (ncpbvdv). infected sheep were killed in pairs on post-inoculation day (pid) 2, 4 and 6. they all exhibited transient leucopenia or lymphopenia, or both. platelet counts decreased but remained within normal limits. bvdv was isolated from buffy coats and tissues of all sheep inoculated with ncpbv ... | 1998 | 9807729 |
| clinical and immunologic responses of vaccinated and unvaccinated calves to infection with a virulent type-ii isolate of bovine viral diarrhea virus. | to determine efficacy of a modified-live type-i isolate of bovine viral diarrhea virus (bvdv) vaccine in protecting calves from infection with a virulent type-ii isolate, and to determine which type of immune response (i.e., humoral or cellular) correlates with protection. | 1998 | 9810390 |
| inactivation of viruses by beta-propiolactone in human cryo poor plasma and igg concentrates. | virus inactivation by cold treatment with beta-propiolactone (bpl) was investigated in human cryo poor plasma and purified igg concentrates spiked with relevant human viruses or appropriate animal model viruses. the samples were treated with 0.1 or 0.25% bpl for 300 or 480 min, respectively. residual infectivity was determined by standard microtitration assays on tissue culture cells. the inactivation of all viruses tested was more effective in igg than in plasma. igg: r1=4-5.5 log10 for vesicul ... | 1998 | 9811521 |
| cis-acting rna elements required for replication of bovine viral diarrhea virus-hepatitis c virus 5' nontranslated region chimeras. | pestiviruses, such as bovine viral diarrhea virus (bvdv), share many similarities with hepatitis c virus (hcv) yet are more amenable to virologic and genetic analysis. for both bvdv and hcv, translation is initiated via an internal ribosome entry site (ires). besides ires function, the viral 5' nontranslated regions (ntrs) may also contain cis-acting rna elements important for viral replication. a series of chimeric rnas were used to examine the function of the bvdv 5' ntr. our results show that ... | 1998 | 9814762 |
| protection of pregnant cattle and their fetuses against infection with bovine viral diarrhea virus type 1 by use of a modified-live virus vaccine. | to determine efficacy of a vaccine containing modified-live bovine viral diarrhea virus (bvdv) type 1 for protecting pregnant cows and their fetuses against virulent heterologous bvdv type 1. | 1998 | 9829398 |
| effect of concurrent experimentally induced bovine respiratory syncytial virus and bovine viral diarrhea virus infection on respiratory tract and enteric diseases in calves. | to compare experimentally induced concurrent bovine viral diarrhea virus (bvdv) and bovine respiratory syncytial virus (brsv) infection with single virus infection. | 1998 | 9829401 |
| insertion of a bovine smt3b gene in ns4b and duplication of ns3 in a bovine viral diarrhea virus genome correlate with the cytopathogenicity of the virus. | bovine viral diarrhea virus (bvdv) infection in cattle can lead to the development of a fatal syndrome called mucosal disease (md). the induction of md requires co-existence of two biotypes of bvdv: cytopathic (cp) and non-cytopathic (ncp). studies have shown that in some cases, cp viruses are generated from ncp viruses by cellular gene insertions, duplications or rearrangements in the viral genome. cellular ubiquitin gene is the most frequently reported insert in bvdv 1. here we report the find ... | 1998 | 9833880 |
| genetic analysis of the internal ribosome entry segment of bovine viral diarrhea virus. | pestiviruses and hepaciviruses are atypical members of the flaviviridae due to their unique biological properties, including the utilization of internal ribosome entry for translation initiation. in contrast to internal initiation in picornaviruses, which depends on numerous canonical initiation factors, the mode of internal ribosome entry in pestiviruses and hepaciviruses resembles prokaryotic translation initiation. to identify functionally important elements within the bovine viral diarrhea v ... | 1998 | 9837801 |
| validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (dclhb) for viral inactivation. | a series of experiments was performed to assess the ability of the heat treatment step used in the manufacture of diaspirin crosslinked hemoglobin (dclhb) to inactivate viruses. in-process solutions (reaction mixtures after the crosslinking process) from six different manufacturing lots were used as test media in a 1:680 scaled down system in which the key process parameters used in the large scale production were duplicated. the inactivation of five different viruses (bovine viral diarrhea viru ... | 1998 | 9844723 |
| use of polymerase chain reaction to simultaneously detect and type bovine viral diarrhoea viruses isolated from clinical specimens. | the techniques of indirect immunofluorescence (if), immuno-peroxidase (ip) staining and the one-step reverse transcriptase polymerase chain reaction (rt-pcr) were compared for detection of 102 isolates of bovine viral diarrhoea virus (bvdv) in infected cell cultures. the bvdv was obtained from bovine clinical specimens, including sera, buffy coats and tissues, submitted from farms located in the states of iowa and wisconsin, united states of america. the if technique detected 88/102 (86.3%) of t ... | 1998 | 9850544 |
| detection of antibodies to bovine viral diarrhoea virus (bvdv) and characterization of genomes of bvdv from brazil. | an elisa for the detection of antibodies to bovine viral diarrhea virus (bvdv) was developed based on antigens derived from a genotype i bvdv strain isolated in switzerland. using monoclonal antibodies we showed that this antigen contained the conserved non-structural protein ns3 whereas it essentially lacked the more strain-specific e2 surface glycoprotein. this elisa has a sensitivity of 97.5% and a specificity of 99.2% as compared to the serum neutralization test (snt). preliminary experiment ... | 1998 | 9850989 |
| a stable cell line with a proportion of cells persistently infected with bovine viral diarrhoea virus. | bovine turbinate (btu) and lamb testis (lt) cell lines persistently infected with bovine viral diarrhoea virus (bvdv) arose as a result of a single change of medium containing commercial foetal calf serum. infected cells comprise 30% and 50% respectively, of the total cell population, determined by immunohistochemical staining. the ratio of positive cells has remained unchanged during successive passages. characterization of the persistently-infected btu cells (btui) showed that only full length ... | 1998 | 9850992 |
| monoclonal antibodies to the e2 protein of a new genotype (type 2) of bovine viral diarrhea virus define three antigenic domains involved in neutralization. | bovine viral diarrhea virus (bvdv) has recently been segregated into two genotypes, namely, bvdv 1 and bvdv 2. viruses of the bvdv 2 genotype are a cause of hemorrhagic and acute fatal disease in cattle in the us and canada. in this study, monoclonal antibodies (mabs) to the newly described bvdv 2 were produced after immunization with virus or a combination of virus and e2 peptide. from an original panel of 17 mabs, 13 mabs were identified as e2-specific by reactivity with a bvdv 2 recombinant e ... | 1998 | 9870585 |
| prolonged nasal shedding and viraemia of cytopathogenic bovine virus diarrhoea virus in experimental late-onset mucosal disease. | a calf persistently infected with bovine virus diarrhoea virus (bvdv) was super-infected with a heterologous bvdv strain, c874, which contained non-cytopathogenic and cytopathogenic viruses. high titres of cytopathogenic bvdv were recovered in the three to four weeks after the challenge. thereafter low titres of cytopathogenic virus were recovered repeatedly from the blood and the nose, with the titres in nasal secretions increasing in the four weeks before the onset of clinical signs. neutralis ... | 1998 | 9871955 |
| new methods for inactivation of lipid-enveloped and non-enveloped viruses. | two new methods are described for inactivating lipid-enveloped and non-enveloped viruses in plasma-derived products such as coagulation factors and intravenous immunoglobulin (igiv). iodine/sephadex delivers iodine to igiv solutions in a slow, controlled way and allows for inactivation of > or = 4 logs of porcine parvovirus (ppv), a hardy non-enveloped virus, under conditions which do not measurably damage the structural or functional properties of the igiv, and with essentially no iodination of ... | 1998 | 9873761 |
| distribution of bovine virus diarrhoea virus in tissues and white blood cells of cattle during acute infection. | this study is performed to gain knowledge about the quantitative distribution of bovine virus diarrhoea virus (bvdv) in tissues and white blood cells (wbc) at different intervals after acute infection. ten specific pathogen-free calves were intranasally inoculated with 10(5) 50% tissue culture infective dose of the non-cytopathic bvdv strain 4800. twelve hours after inoculation tonsil biopsies were taken and wbc were collected daily for virus isolation and titration. each day one calf was killed ... | 1998 | 9874100 |
| anti-viral effect of interferon-alpha on bovine viral diarrhea virus. | to get basic information to control persistent virus infection among domestic animals by cytokines, the antiviral activity of four natural human cytokines against bovine viral diarrhea virus (bvdv) was evaluated. normal bovine peripheral blood mononuclear leukocytes (pbml) and fetal bovine muscular cells (fbmc) were treated with varying doses of human interferon (ifn)-alpha, ifn-gamma, tumor necrosis factor (tnf)-alpha and tnf-beta. the antiviral activity in treated cells was measured by the tit ... | 1998 | 9879534 |
| evidence for biotype-specific effects of bovine viral diarrhoea virus on biological responses in acutely infected calves. | the relationship between the two biotypes of bovine viral diarrhoea virus (bvdv) and the biological responses they induce was studied in 3- to 6-month-old calves inoculated intranasally with a homologous pair of non-cytopathic and cytopathic strains. marked differences in virological and serological events occurred following exposure to a specific bvdv strain. the non-cytopathic biotype was frequently recovered from nasal secretions and blood cells during the first 28 days post-inoculation where ... | 1998 | 9460918 |
| a new assay for classical swine fever virus based on cytopathogenicity in porcine kidney cell line fs-l3. | a new assay termed the dome disappearance method for classical swine fever virus (csfv) using fs-l3 cells with serum-free culture medium was developed. the csfv live vaccine gpe- strain grows well and shows a slight cytopathic effect (cpe) in fs-l3 cells. this cpe results in the disappearance of the unique fluid-filled multicellular domes on a single monolayer of fs-l3 cells. by using this phenomenon, dome disappearance, as a marker of infection, it was possible to determine the titers of csfv a ... | 1998 | 9506817 |
| replication of cytopathic and noncytopathic bovine viral diarrhea virus in zona-free and zona-intact in vitro-produced bovine embryos and the effect on embryo quality. | the aim of the present study was to determine whether or not cytopathic (cp) and noncytopathic (ncp) bovine viral diarrhea virus (bvdv) are able to replicate within in vitro-produced embryos and to investigate whether inoculation of embryos with bvdv affects their normal development. zona pellucida (zp)-free oocytes, zygotes, 8-cell-stage embryos, morulae, and hatched blastocysts (hb) were incubated for 1 h in 1 ml of minimal essential medium containing 10(6.00) tissue culture infectious dose (t ... | 1998 | 9510977 |
| changes in levels of viremia in cattle persistently infected with bovine viral diarrhea virus. | virus isolation and serum neutralizing antibody titers were determined over a period of time from samples collected from animals persistently infected with bovine viral diarrhea virus (bvdv). to evaluate over time the ability to detect bvdv by virus isolation from serum or white blood cell preparations, 4 persistently infected calves were monitored from birth until 70 days of age. in 3 of 4 persistently infected calves, virus isolation from serum and white blood cells was negative until approxim ... | 1998 | 9526856 |
| severe acute bovine viral diarrhea in ontario, 1993-1995. | in 1993, noncytopathic bovine viral diarrhea virus (bvdv) strains with enhanced virulence caused unprecedented outbreaks of severe acute bovine viral diarrhea (bvd) in dairy, beef, and veal herds in ontario (canada). fever, pneumonia, diarrhea, and sudden death occurred in all age groups of cattle. abortions often occurred in pregnant animals. gross lesions in the alimentary tract were similar to those associated with mucosal disease, especially in animals >6 months of age. cattle of all age gro ... | 1998 | 9526857 |
| evaluation of a single dilution elisa system for detection of seroconversion to bovine viral diarrhea virus, bovine respiratory syncytial virus, parainfluenza-3 virus, and infectious bovine rhinotracheitis virus: comparison with testing by virus neutralization and hemagglutination inhibition. | a single-dilution quantitative enzyme-linked immunosorbent assay (elisa) system, based on commercial elisa kits, for the simultaneous detection of seroconversion to bovine viral diarrhea virus (bvdv), bovine respiratory syncytial virus (brsv), parainfluenza-3 virus (pi3v), and infectious bovine rhinotracheitis virus (ibrv) was evaluated by testing acute and convalescent serum pairs from 564 cattle in 145 outbreaks of respiratory disease. seroconversion to bvdv, brsv, pi3v and ibrv was detected i ... | 1998 | 9526859 |
| the replicative intermediate molecule of bovine viral diarrhoea virus contains multiple nascent strands. | the replication of bovine viral diarrhoea virus (bvdv) rna is considered to involve replicative intermediates (ri) and replicative forms (rf) of virus rna. these rna species were radiolabelled metabolically by 3h-uridine in bvdv-infected cells and separated by sucrose gradient centrifugation. rna in the fractions was then digested with rnase a in high salt (2 x ssc) and the rnase-resistance was determined. using the baltimore formula, this led to the calculation that the ri of bvdv contained 6-7 ... | 1998 | 9541623 |
| a monoclonal antibody-based immunoperoxidase monolayer (micro-isolation) assay for detection of type 1 and type 2 bovine viral diarrhea viruses. | a monoclonal antibody (mab)-based immunoperoxidase monolayer assay (ipma) for detection of bovine viral diarrhea virus (bvdv) was developed and compared with an existing bovine polyclonal antibody (pab)-based ipma. a pool of 5 mabs, 4 mabs produced to a type 1 bvdv and 1 mab produced to a type 2 bvdv, was utilized in the mab-ipma. the mabs were chosen for inclusion in the pool because of their broad cross-reactivities with type 1 and/or type 2 bvdv, their apparent avidities for antigen, their re ... | 1998 | 9553717 |
| expression of a 50 kda putative receptor for bovine viral diarrhea virus in bovine fetal tissues. | the expression of a 50 kda bovine viral diarrhea virus putative receptor in different bovine fetal tissues from 3-month old fetuses was studied. the receptor expression was examined by immunocytochemical staining and by immunoblotting using antiidiotypic probe (anti-d89). intense specific staining in enterocytes of the small and large intestines, cortical tubular epithelial cells of kidneys, respiratory epithelial cells of the trachea and esophageal mucosal epithelial cells was observed, demonst ... | 1998 | 9553718 |
| transport of viruses through fetal membranes: an in vitro model of perinatal transmission. | a model system for perinatal transmission of viral infections was developed and transport of infectious virus particles through fetal membranes was investigated. viruses of different families known to cause serious intrauterine infections were selected, including relevant and model viruses: the dna-viruses hsv-1 and -2 as well as the animal herpes viruses bhv-1 and shv-1, the rna-virus bvdv as a model for hepatitis c virus, hiv-1 and -2, and ppv as a model for parvovirus b19. migration of infect ... | 1998 | 9557298 |
| bovine viral diarrhea virus strain oregon: a novel mechanism for processing of ns2-3 based on point mutations. | bovine viral diarrhea virus (bvdv) isolates can either be cytopathogenic (cp) or noncytopathogenic (noncp). while both biotypes express the nonstructural protein ns2-3, generation of ns3 strictly correlates with the cp phenotype. the production of ns3 is usually caused by cp specific genome alterations, which were found to be due to rna recombination. molecular analyses of the cp bvdv strain oregon revealed that it does not possess such genome alterations but nevertheless is able to generate ns3 ... | 1998 | 9557702 |
| insertion of a sequence encoding light chain 3 of microtubule-associated proteins 1a and 1b in a pestivirus genome: connection with virus cytopathogenicity and induction of lethal disease in cattle. | pestiviruses represent the first rna viruses for which recombination with cellular protein-coding sequences has been reported. as a result of such recombinations cytopathogenic (cp) pestiviruses can develop from noncytopathogenic (noncp) viruses. in the case of bovine viral diarrhea virus (bvdv), the generation of cp mutants is linked to the induction of the lethal syndrome mucosal disease (md) in cattle. the cp bvdv jacp was isolated from an animal which had come down with md. the genome of jac ... | 1998 | 9557703 |
| a novel method for pestivirus genotyping based on palindromic nucleotide substitutions in the 5'-untranslated region. | a simple and practical method was developed for pestivirus genotyping based on analysis of the secondary structures in the 5'-untranslated region (utr). three stable stem-loop structures, v1, v2 and v3, predicted by computer in the 5'-utr, included strictly conserved consensus base-pairings which are shared by all the genotypes of pestivirus or are characteristic to each genotype of pestivirus. on the basis of the palindromic nucleotide substitution at the secondary structural level, six genotyp ... | 1998 | 9562417 |
| infectious bovine viral diarrhea virus (strain nadl) rna from stable cdna clones: a cellular insert determines ns3 production and viral cytopathogenicity. | bovine viral diarrhea virus (bvdv), strain nadl, was originally isolated from an animal with fatal mucosal disease. this isolate is cytopathic in cell culture and produces two forms of ns3-containing proteins: uncleaved ns2-3 and mature ns3. for bvdv nadl, the production of ns3, a characteristic of cytopathic bvdv strains, is believed to be a consequence of an in-frame insertion of a 270-nucleotide cellular mrna sequence (called cins) in the ns2 coding region. in this study, we constructed a sta ... | 1998 | 9573238 |
| complete genomic sequence of border disease virus, a pestivirus from sheep. | the genus pestivirus of the family flaviviridae comprises three established species, namely, bovine viral diarrhea virus (bvdv), classical swine fever virus (csfv), and border disease virus from sheep (bdv). in this study, we report the first complete nucleotide sequence of bdv, that of strain x818. the genome is 12,333 nucleotides long and contains one long open reading frame encoding 3, 895 amino acids. the 5' noncoding region (ncr) of bdv x818 consists of 372 nucleotides and is thus similar i ... | 1998 | 9573288 |
| detection of bovine viral diarrhea virus in the ovaries of cattle acutely infected with bovine viral diarrhea virus. | bovine viral diarrhea virus (bvdv) is recognized worldwide as a major cause of economic loss in cattle. infection with bvdv can result in several clinical outcomes. however, the reproductive consequences may be the most important. infertility, early embryonic death, abortion, and congenital anomalies have all been reported following acute infection with bvdv. the cause of infertility following acute bvdv infection is not known. bvdv has been isolated from the bovine ovary and has been associated ... | 1998 | 9576337 |
| detection of cytopathic bovine viral diarrhea virus in the ovaries of cattle following immunization with a modified live bovine viral diarrhea virus vaccine. | economic loss from infection with bovine viral diarrhea virus (bvdv) is of worldwide concern. the unique pathogenesis and antigenic variability of bvdv have made this virus challenging to control. vaccination programs are a major component of control and prevention strategies. both killed and modified live vaccines are commercially available. choice between killed and modified live vaccines is controversial. of major concern is the safety of modified live vaccines. little information is availabl ... | 1998 | 9576338 |
| prevalence of bovine viral diarrhea virus genotypes and antibody against those viral genotypes in fetal bovine serum. | one thousand lots of pooled fetal bovine serum (fbs) were tested for contamination with bovine viral diarrhea virus (bvdv) and/or for contamination with neutralizing antibody against bvdv. noncytopathic or cytopathic bvdv was isolated from 203 lots of fbs. analysis of the viral isolates identified 115 type 1 and 65 type 2 bvdv isolates. an additional 23 virus isolates were mixtures of > or = 2 bvdv isolates and were not classified to viral genotype. further characterization of the type 1 viruses ... | 1998 | 9576339 |
| distribution of antibody titers to bovine viral diarrhea virus in infected, exposed, and uninfected beef cattle. | 1998 | 9576349 | |
| prevalence of antibodies to bovine virus diarrhoea virus and other viruses in bulk tank milk in england and wales. | bulk tank milk samples from 1070 dairy herds in england and wales were tested by elisa for antibodies to bovine virus diarrhoea virus (bvdv). a subset of 341 herds was tested by elisa for antibodies to bovine herpesvirus 1 (bhv-1), bovine respiratory syncytial virus (brsv) and bovine coronavirus (bcv). none of the herds had less than 40 dairy cows and none had been vaccinated against bvdv. the prevalence of bvdv antibody-positive herds in the national population was estimated at 95 per cent and ... | 1998 | 9586130 |
| the duration of antibodies against bovine virus diarrhoea virus in bulk milk. | fifty-eight dairy herds, suspected to be recently infected with bovine virus diarrhoea virus (bvdv) due to a rise in bvdv antibodies in bulk milk, were followed over a two-year period. in 34 (59%) of these 58 herds (group 1), pooled milk samples from heifers or pooled blood samples from calves were negative for bvdv antibodies. in this group as many as 53 and 76% of the herds again had antibody-negative bulk milk one and two years after the positive sample, respectively. of the remaining herds, ... | 1998 | 9592949 |
| the effect of bovine virus diarrhoea virus on reproduction in recently infected norwegian dairy herds. | a group of 32 dairy herds, recently infected with bovine virus diarrhoea virus (bvdv), was compared with a control group consisting of 75 bvdv free herds during a 3-year-period. variables related to reproduction were registered. results of multiple antibody examinations in bulk milk as well as samples of milk and blood from younger animals were used to select the herds. the incidence of abortions was statistically significantly different in the 2 groups, while the number of stillbirths, weak bor ... | 1998 | 9592950 |
| mapping of a type 1-specific and a type-common epitope on the e2 (gp53) protein of bovine viral diarrhea virus with neutralization escape mutants. | bovine viral diarrhoea viruses (bvdv) have recently been segregated into two genotypes, bvdv 1 and bvdv 2. however, the antigenic differences and similarities of bvdv 1 and bvdv 2 remain poorly defined. in this study, the e2 epitopes of two neutralizing monoclonal antibodies (mabs) produced against an isolate of bvdv 1 were mapped. the mab 157, previously determined to be broadly cross-reactive to bvdv, was discovered to be bvdv 1-specific, whereas mab 348 bound to and neutralized bvdv 2. both m ... | 1998 | 9617771 |
| the immune response of cattle, persistently infected with noncytopathic bvdv, after superinfection with antigenically semi-homologous cytopathic bvdv. | cattle persistently infected (pi) with noncytopathic (ncp) bovine virus diarrhea virus (bvdv) are at risk for developing fatal mucosal disease (md), which is considered to occur after superinfection with antigenically homologous cytopathic (cp) bvdv. in this study, we intranasally inoculated four pi-animals, that were pi with 2 ncp bvdv strains with 10(5) tcid50 antigenically closely related cp bvdv. two pi-animals were inoculated with 10(5) tcid50 ncp bvdv and one pi-animal, with virus free cel ... | 1998 | 9618867 |
| [pestivirus as causative agent of abortion and perinatal mortality in cattle and sheep in switzerland]. | the causal involvement of bovine viral diarrhoea virus (bvdv) and border disease virus (bdv) infection in bovine and ovine abortion and perinatal mortality remain unclear. from 1992 until 1994, 213 bovine and 31 ovine foetuses as well as 36 calves and 25 lambs which had died perinatally were investigated. tissue samples were tested for the presence of pestiviruses and serum or fluid from the body cavities were analysed for the presence of pestivirus antibodies. detection of pestiviruses was perf ... | 1998 | 9618985 |
| the ns5a/ns5 proteins of viruses from three genera of the family flaviviridae are phosphorylated by associated serine/threonine kinases. | phosphorylation of the expressed ns5a protein of hepatitis c virus (hcv), a member of the hepacivirus genus of the family flaviviridae, has been demonstrated in mammalian cells and in a cell-free assay by an associated kinase activity. in this report, phosphorylation is also shown for the ns5a and ns5 proteins, respectively, of bovine viral diarrhea virus (bvdv) and yellow fever virus (yf), members of the other two established genera in this family. phosphorylation of bvdv ns5a and yf ns5 was ob ... | 1998 | 9621090 |
| a novel nested reverse transcription pcr detects bovine viral diarrhoea virus in fluids from aborted bovine fetuses. | a nested reverse transcription-pcr (rt-pcr) was developed to detect pestivirus nucleic acid in fetal fluids and to study the number of bovine abortions associated with bvdv infection. three techniques for the extraction of viral rna from fetal fluids were compared; phenol:chloroform method, treatment with catrimox-14 followed by guanidium isothiocyanate buffer and the qiagen total rna kit. the qiagen kit was the most sensitive and reproducible and therefore adopted. after cdna synthesis, initial ... | 1998 | 9628223 |
| persistent bovine pestivirus infection localized in the testes of an immuno-competent, non-viraemic bull. | a post-pubertal bull on an artificial insemination station was found to be persistently shedding bovine viral diarrhoea virus (bvdv) in semen over a period of eleven months, while demonstrating no viraemia. circulating antibodies to bvdv were consistently high, suggesting that the immune system was challenged repeatedly. post-mortem findings confirmed that the virus was sequestered in the testes of the bull. it is hypothesized that the bvdv in this immuno-competent bull was protected from the bu ... | 1998 | 9631528 |
| persistently infected cattle stabilise bovine viral diarrhea virus leading to herd specific strains. | animals persistently infected with bvdv are important in the epizootiology of the bovine viral diarrhea (bvd) because they are a permanent source of contamination within a herd. these animals produce large quantities of virus and have, therefore, been proposed as responsible for generating antigenic variability. however, limited studies have failed to detect antigenic or genetic changes in viruses isolated at different time from persistently infected animals. one hypothesis to account for this s ... | 1998 | 9631529 |
| differentiation of types 1a, 1b and 2 bovine viral diarrhoea virus (bvdv) by pcr. | there are two genotypes among bovine viral diarrhoea viruses (bvdv), bvdv1 and bvdv2. within the bvdv1 genotype there are two distinct subgenotypes, bvd1a and bvd1b. serology and monoclonal antibody binding are used to differentiate bvdv from classical swine fever virus (csfv) and border disease virus (bdv), the other members of the pestivirus genus. these techniques are less useful in the differentiation and segregation of viruses within the bvdv species. in this study, differential polymerase ... | 1998 | 9633045 |
| bovine viral diarrhea virus replication in bovine follicular epithelial cells derived from persistently infected heifers. | bovine follicle fluid and oocytes surrounded by follicular epithelial (fe) cells were collected from ovaries of two heifers persistently infected with bovine viral diarrhea virus (bvdv). bvdv was present in the follicle fluid at a higher titer than in serum. the oocytes were matured in vitro under culture conditions of 39 degrees c in humidified air containing 5% co2. in vitro fertilization was performed after 24 hr in culture (the day of insemination was defined as day 1), and culture was conti ... | 1998 | 9637289 |
| segregation of bovine viral diarrhea virus isolated in japan into genotypes. | it was suggested that 3 strains of bovine viral diarrhea virus (bvdv) isolated from persistently infected calves in tochigi prefecture in japan belonged to bvdv type ii. it was recognized lack of psti site on the 5'-untranslated region of genome of them as well as bvdv type ii reported previously. inoculated with the 3 strains, the calves showed the mild decrease of platelet counts which was specific clinical sign of bvdv type ii. we should report that the 3 strains were the first bvdv type ii i ... | 1998 | 9637291 |
| experimental induction of mucosal disease: consequences of superinfection of persistently infected cattle with different strains of cytopathogenic bovine viral diarrhea virus. | mucosal disease (md) can be induced in cattle persistently infected with noncytopathogenic bovine viral diarrhea virus (ncp bvd virus) by superinfecting them with antigenically related cytopathogenic (cp) bvd virus strains. while some of these animals succumb to early onset md after 2 to 3 weeks post infectionem (p.i.), others only react by producing neutralizing antibodies against the cp bvd virus strain and may develop late onset md after longer incubation periods. the aim of this study was to ... | 1998 | 9638140 |
| nucleotide sequence homology to bovine viral diarrhea virus 2 (bvdv 2) in the 5' untranslated region of bvdvs from cattle with mucosal disease or persistent infection in japan. | cytopathogenic and non-cytopathogenic bovine viral diarrhea viruses (bvdvs) were isolated from cattle with mucosal disease or persistent infection in japan. these isolates were compared for antigenic properties by cross-neutralization tests with japanese reference strains of bvdv belonging to classical type 1. significantly low cross-reactivity to reference strains was noted, indicating the viruses to possibly represent a new serotype in japan. thus, to determine the genotype of the isolates, nu ... | 1998 | 9646457 |
| [clinical-virologic course after superinfection of persistently infected cattle with cytopathogenic bovine viral diarrhea virus strains]. | vaccination with live cytopathogenic (cp) bovine viral diarrhoea virus (bvdv) is often used for control of this disease. in animals which are persistently infected with noncytopathogenic (ncp) bvdv this can lead to the outbreak of mucosal disease (md). to simulate vaccination of such animals and to monitor the clinical-virological course after superinfection, nine clinically healthy calves which were persistently viremic were superinfected with different cp bvdv strains. one animal succumbed to ... | 1998 | 9646556 |
| genome instability in bvdv: an examination of the sequence and structural influences on rna recombination. | the cytopathogenic biotype of the pestivirus, bovine viral diarrhea virus, is frequently a product of nonhomologous recombination in the region of the genome encoding the viral ns2-ns3 proteins. the possibility that sequences or structures in this region contributed to a hotspot for rna recombination was examined. a pcr-based strategy was used to examine viral genomic rna isolated from tissue samples of cattle persistently infected with the noncytopathogenic biotype of the virus. analysis of two ... | 1998 | 9657953 |
| specificity and duration of neutralizing antibodies induced in healthy cattle after administration of a modified-live virus vaccine against bovine viral diarrhea. | to determine the duration for cross-neutralizing antibodies stimulated by administration of a single dose of a modified-live vaccine against bovine viral diarrhea virus (bvdv) to seronegative cattle. | 1998 | 9659549 |
| virus validation of ph 4-treated human immunoglobulin products produced by the cohn fractionation process. | to assess the virus reducing capacity of cohn's cold ethanol fractionation process for the production of intravenous (ivig) and intramuscular (imig) immunoglobulin products, and treatment of these products at ph 4, a validation study of virus removal and/or inactivation was performed using both lipid-enveloped viruses [human immunodeficiency virus (hiv), bovine viral diarrhoea virus (bvdv) and pseudorabies virus (psr)], and non-lipid-enveloped viruses [(simian virus 40 (sv40) and encephalomyocar ... | 1998 | 10403030 |
| removal of viruses from human intravenous immune globulin by 35 nm nanofiltration. | viral safety is an important prerequisite for clinical immunoglobulin preparations. a common manufacturing practice is to utilize several virus removal/inactivation process steps to ensure the safety of human intravenous immunoglobulin (ivig). in this regard, we examined the use of planova 35 nm filters to reduce potential loads of both non-enveloped and enveloped viruses prior to end-stage solvent detergent treatment. the nanofiltration process was validated for removal of a variety of envelope ... | 1998 | 10403036 |
| phylogenetic evidence for the improved rna higher-order structure in internal ribosome entry sequences of hcv and pestiviruses. | the strong requirement for a small segment of the 5'-proximal coding sequence of hepatitis c virus (hcv) is one of the most remarkable features in the internal initiation of hcv mrna translation. phylogenetic analysis and rna folding indicate a common rna structure of the 5' untranslated region (utr) of hcv and the animal pestiviruses, including hcv types 1-11, bovine viral diarrhea (bvdv), border disease virus (bdv) and hog cholera (hocv). although the common rna structure shares similar featur ... | 1998 | 9926403 |
| changes in ovarian follicles following acute infection with bovine viral diarrhea virus. | bovine viral diarrhea virus (bvdv) has been associated with several reproductive problems in cattle, including poor fertility, early embryonic deaths, abortion and congenital anomalies. little is known about the cause of poor fertility in cows acutely infected with bvdv. the purpose of this study was to identify changes in ovarian function following acute infection with noncytopathic bvdv. the ovaries of 5 bvdv sero-negative and virus-negative pubertal heifers were monitored daily for 4 consecut ... | 1998 | 10732038 |
| association of bovine embryos produced by in vitro fertilization with a noncytopathic strain of bovine viral diarrhea virus type ii. | in the first experiment, heifers were infected experimentally with bovine viral diarrhea virus type ii (bvdv-type ii, strain cd87; characterized by high morbidity and mortality). subsequently, in vitro fertilized embryos were produced from oocytes collected on day 4, 8, and 16 post infection. in a total of 29 heifers, the infectious virus was detected in 55% of the samples of the follicular fluid, in 10% of the oviductal cells, in 10% of the uterine flushes and in 41% of the in vitro fertilized ... | 1998 | 10732060 |
| washing and trypsin treatment of in vitro derived bovine embryos exposed to bovine viral diarrhea virus. | gametes, somatic cells and materials of animal origin in media are potential sources for introducing bovine viral diarrhea virus (bvdv) into systems for production of ivf bovine embryos. further, the efficacy of washing and trypsin treatment for removal of bvdv from ivf embryos is questionable. washing and trypsin treatments recommended by the international embryo transfer society for in vivo-derived embryos were applied to in vitro-derived, virus-exposed, bovine embryos in this side-by-side com ... | 1998 | 10734446 |
| noncytopathogenic bovine viral diarrhea virus (bvdv) reduces cleavage but increases blastocyst yield of in vitro produced embryos. | the growing application of in vitro embryo production systems that utilize slaughterhouse tissues of animals of unknown health status conveys the risk of disease transmission. one pathogen of concern in this regard is bovine viral diarrhea virus (bvdv), and the objective of this study was to investigate the effect of bvdv on in vitro embryonic development. a bovine in vitro embryo production system was experimentally infected with bvdv at 2 stages: prior to in vitro maturation by incubating cumu ... | 1998 | 10734451 |
| collective experiences of adventitious viruses of animal-derived raw materials and what can be done about them. | contamination of animal-derived raw materials with viruses, mycoplasmas, bacteria and fungi is common. these contaminants can interfere with the diagnosis of viral infection, and vaccines produced using infected cell cultures could lead to seroconversion or disease in the vaccinated animal. the purity, safety and efficacy of viral vaccines requires testing of the ingredients, cell substrates and final product. methods for detection of viruses, especially bovine viral diarrhea virus, in nutrient ... | 1998 | 19003405 |
| genetic typing of pestiviruses from new zealand. | to investigate the genetic type of 20 pestiviruses collected from new zealand over the period 1967-97. | 1998 | 16032008 |
| embryo transfer from donor cattle persistently infected with bovine viral diarrhea virus. | this study was done to examine the reproductive efficiency of embryo transfer donors that were persistently infected with bovine viral diarrhea virus (bvdv) and to determine the potential for vertical or horizontal transmission of bvdv during embryo transfer from persistently infected donors. the reproductive inefficiency of 7 different persistently infected donors was evident by consistent failure at superovulation and/or fertilization. washing of embryos according to the reccommendations of th ... | 1997 | 16728033 |
| in vitro fertilization and in vitro culture of bovine embryos in the presence of noncytopathic bovine viral diarrhea virus. | in vitro embryo production has been used extensively in research and is now offered as a commercial service, yet the hazards of introducing specific infectious agents into in vitro embryo production systems have not been completely defined. the introduction of noncytopathic bovine viral diarrhea virus (bvdv) is a special concern. one objective of this study was to determine if noncytopathic bvdv-infected uterine tubal cells in ivf and ivc systems affected the rate of cleavage and development. an ... | 1997 | 16728117 |
| organ and tissue distribution of the antigen of the cytopathogenic bovine virus diarrhea virus in the early and advanced phase of experimental mucosal disease. | to study the development of lesions in mucosal disease, the spread of cytopathogenic (cp) bovine virus diarrhea virus (bvdv) to different organs was examined in relation to the time post inoculation (pi). mucosal disease was induced in 15 persistently viremic cattle from two herds by intranasal inoculation with antigenically similar cp bvdv strain. this strain reacted with one additional monoclonal antibody when compared to the corresponding herd-specific non cytopathogenic (ncp) isolate. twelve ... | 1997 | 9672623 |
| diagnostic studies of abortion in danish dairy herds. | diagnostic findings in 218 aborted bovine foetuses are reported. the materials were examined in a matched case-control study of 69 danish dairy herds with a sudden increase in the number of abortions and a corresponding 69 control herds. foetuses aborted during the subsequent 6-month period were examined to identify the cause of abortion if possible. a total of 186 specimens were submitted from case herds and 32 from control herds. a likely cause of abortion was diagnosed in 73 foetuses. the mos ... | 1997 | 9465775 |
| level of viral antigen in blood leucocytes from cattle acutely infected with bovine viral diarrhoea virus. | blood samples from 24 calves undergoing experimental acute infection with a non-cytopathogenic bovine viral diarrhoea virus (bvdv) were examined for viral antigen in peripheral leucocytes with an enzyme-linked immunosorbent assay (elisa), and for presence of virus in blood plasma in a cell culture assay. with the antigen elisa, low positive values were detected in leucocytes sampled on days 3-4 from two of eight animals inoculated intranasally, and on days 11-13 from three of 16 animals inoculat ... | 1997 | 9467300 |
| authentic and chimeric full-length genomic cdna clones of bovine viral diarrhea virus that yield infectious transcripts. | bovine viral diarrhea virus (bvdv) is the most insidious and devastating viral pathogen of cattle in the united states. disease control approaches must be based on detailed knowledge of virus biology. to develop reverse-genetic systems to study the molecular biology of the virus, we first constructed a plasmid containing the entire genome of bvdv cloned as cdna. subsequently, we showed that infectious bvdv was produced by cells transfected with uncapped rna transcribed in vitro from the cdna clo ... | 1997 | 8985373 |
| macrophages infected with cytopathic bovine viral diarrhea virus release a factor(s) capable of priming uninfected macrophages for activation-induced apoptosis. | bovine bone marrow-derived macrophages infected with the cytopathic biotype of bovine viral diarrhea virus released an antiviral activity into the supernatant which was tentatively characterized as type i interferon because of its physicochemical properties. such supernatants primed both infected and uninfected macrophages for decreased nitric oxide production and apoptosis in response to lipopolysaccharide. this finding strongly suggests a role of this pathway in the pathogenesis of mucosal dis ... | 1997 | 9060690 |
| immune suppression in calves with bovine immunodeficiency virus. | the present study was designed to evaluate the effect of bovine immunodeficiency virus (biv) infection on immune functions and possible interactions between biv and other bovine viruses in calves. ten calves were inoculated intravenously with biv, and five served as controls. an increased lymphocyte proliferation to biv gag protein was demonstrated 2 to 6 weeks after biv inoculation (p < 0.05). lymphocyte subset differentiation revealed a decreased cd4/cd8 ratio (p < 0.05) during weeks 2 to 7, s ... | 1997 | 9067663 |
| bovine viral diarrhoea virus infection in bone marrow of experimentally infected calves. | colostrum-deprived calves were inoculated with either a field isolate of bovine viral diarrhoea virus (bvdv) containing cytopathogenic (cp) and noncytopathogenic (ncp) biotypes or with only the ncp biotype. paraffin wax-embedded sections of bone marrow from these calves, examined by means of an immunoperoxidase method, showed bvdv antigen in megakaryocytes and myeloid cells. infection of such cells may play a role in the pathogenesis of thrombocytopenia, leucopenia and neutropenia, as reported i ... | 1997 | 9076604 |
| immunohistochemical detection of hog cholera viral glycoprotein 55 in paraffin-embedded tissues. | formalin-fixed, paraffin embedded tissues obtained from 40 pigs inoculated with a field isolate of hog cholera virus were examined for the presence of gp55, a major structural protein of the virus envelope, using a monoclonal antibody-based immunohistochemical test with the avidin-biotin-peroxidase complex method. immunoreactivity was detected in hog cholera virus-infected tissues but not in control pigs tissues, african swine fever virus-infected tissues, or bovine viral diarrhea virus-infected ... | 1997 | 9087919 |
| standardization of enzyme-linked immunosorbent assays (elisas) for quantitative estimation of antibodies specific for infectious bovine rhinotracheitis virus, respiratory syncytial virus, parainfluenza-3 virus, and bovine viral diarrhea virus. | commercial enzyme-linked immunosorbent assays (elisas) for detection of serum antibodies to bovine viral diarrhea virus (bvdv), parainfluenza-3 virus (pi3v), respiratory syncytial virus (rsv), and infectious bovine rhinotracheitis virus (ibrv) were standardized to give a quantitative result when testing was performed at a single optimum dilution. for each test, serum samples were titrated and their end point titers calculated by an algebraic method directly from a plot of each titration series a ... | 1997 | 9087921 |
| losses over a 2-year period associated with fetal infection with the bovine viral diarrhea virus in a beef cow-calf herd in saskatchewan. | in 1992, significant calf losses occurred between birth and weaning in a 650-cow saskatchewan beef herd. these losses occurred subsequent to ill-thrift and disease, and every calf necropsied was found to be persistently infected with bovine viral diarrhea virus (bvdv). the objectives of this study were to describe the losses associated with fetal infection with bvdv in this herd and to determine why they occurred. for investigative purposes, blood samples were collected from the entire cow herd ... | 1997 | 8993781 |
| performance, survival, necropsy, and virological findings from calves persistently infected with the bovine viral diarrhea virus originating from a single saskatchewan beef herd. | fifty-one calves from 652 cows and heifers that calved on a saskatchewan ranch in 1992 were identified as persistently infected with bovine viral diarrhea virus (bvdv), based on virological and necropsy findings. herd records suggested a further 20 calves that died between birth and weaning were probably also persistently infected. subsequent to weaning, all surviving persistently infected calves were transferred to one pen in a 10,000 head commercial feedlot, to mimic normal management practice ... | 1997 | 8993782 |
| recovery of cytopathogenic and noncytopathogenic bovine viral diarrhea viruses from cdna constructs. | 1997 | 8995710 | |
| antigenic variation among bovine viral diarrhea virus (bvdv) strains and the role of different cell fixation methods in immunoassays. | antigenic variation among 13 quebec isolates of bovine viral diarrhea virus (bvdv), 4 reference strains and 2 american isolates were studied by peroxidase-linked antibody assay (pla assay) and neutralization test (nt). the quebec strains consisted of 3 isolates before 1993 and 10 isolates from 1993. in the pla assay, we compared 2 different fixatives, acetone and formalin. acetone-fixation allowed us to identify 6 groups from amongst the viruses tested. all the quebec isolates were different fro ... | 1997 | 9008798 |
| immune response to vaccination with dna encoding the bovine viral diarrhea virus major glycoprotein gp53 (e2). | bovine viral diarrhea virus (bvdv) is a worldwide pathogen in cattle which has not been controlled by classical vaccination. the region encoding the bvdv major glycoprotein gp53 (e2) known to possess virus-neutralizing activity was cloned into a mammalian expression vector under the human cytomegalovirus (cmv) intermediate early promoter. intramuscular and intradermal administration of the recombinant plasmid dna into balb/c mice induced bvdv gp53-specific antibody responses to both biotypes (cy ... | 1997 | 9011043 |
| continued bvdv education needed. | 1997 | 9018340 | |
| detection and identification of ruminant and porcine pestiviruses by nested amplification of 5' untranslated cdna regions. | based on published gene sequences of bovine viral diarrhoea virus (bvdv) type i and classical swine fever virus (csfv), genus- and species-specific primers were designed to detect and identify pestivirus cdna sequences in a nested polymerase chain reaction (pcr). the pcr primers were validated using cdna synthesized from 146 pestivirus isolates, comprising representatives of all four so far described genotypes (bvdv type i, bvdv type ii, csfv and border disease virus), as well as others of uncer ... | 1997 | 9029529 |
| genetic characterization of ruminant pestiviruses: sequence analysis of viral genotypes isolated from sheep. | historically, the genus pestivirus was believed to contain three species of viruses; bovine viral diarrhea virus (bvdv), border disease virus (bdv) and classical swine fever virus (csfv). however, based on limited sequence analysis of a small number of pestiviral isolates from domestic livestock, evidence has recently emerged indicating that at least four distinct genotypes exist. in an attempt to gain a better understanding of the degree of viral variation among ruminant pestiviruses, the entir ... | 1997 | 9037733 |