Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| subdivision of the pestivirus genus based on envelope glycoprotein e2. | conventionally, the genus pestivirus of the family flaviviridae has been divided into bovine viral diarrhea virus (bvdv), classical swine fever virus (csfv), and border disease virus (bdv). to date, bdv and bvdv have been isolated from different species, whereas csfv seems to be restricted to swine. pestiviruses are structurally and antigenically closely related. envelope glycoprotein e2 is the most immunogenic and most variable protein of pestiviruses. we cloned e2 genes of many different pesti ... | 1997 | 9356345 |
| inhibition of pestivirus infection in cell culture by envelope proteins e(rns) and e2 of classical swine fever virus: e(rns) and e2 interact with different receptors. | pure preparations of envelope glycoproteins e(rns) and e2 of classical swine fever virus (csfv) synthesized in insect cells were used to study infection of porcine and bovine cells with the pestiviruses csfv and bovine viral diarrhoea virus (bvdv). almost 100% inhibition of infection of porcine kidney cells with csfv was produced by 100 microg/ml e(rns). after removal of the virus no e(rns) was needed in the overlay medium (growth medium) to maintain this level of inhibition. in contrast, 100% i ... | 1997 | 9367363 |
| bovine respiratory tract disease caused by bovine viral diarrhea virus. | although several viruses and bacteria are capable of inducing bovine respiratory tract disease, a pivotal organism in the cause of this complex disease may be bovine viral diarrhea virus (bvdv). circumstantial evidence has long supported this hypothesis. it is frequently present in diseased respiratory tract tissues often together with other viruses or bacteria. field observations suggest marked synergism occurs. researchers have confirmed that, in most instances, the virus itself elicits only a ... | 1997 | 9368990 |
| a method to detect bovine viral diarrhea virus contamination in cell cultures using immunoperoxidase staining. | 1997 | 9376437 | |
| immunohistochemical diagnosis of pestivirus infection associated with bovine and ovine abortion and perinatal death. | to establish a reliable, rapid, economical method for detection of pestivirus infection in bovine and ovine fetuses and to examine participation of these viruses in abortions and neonatal mortality. | 1997 | 9401683 |
| genotypic analysis of the 5'-untranslated region of a pestivirus strain isolated from human leucocytes. | the 5'-untranslated genomic region of the pestivirus strain europa, originated in human leucocytes and previously identified as bovine diarrhea virus (bvdv), was amplified by reverse transcription-pcr and sequenced. analyses based on primary nucleotide sequence homology and on secondary palindromic sequence structures characteristic to genotypes revealed that this human isolate should be assigned to a novel genotype of pestivirus, type ic. this newly emerged genotype was related to, but distingu ... | 1997 | 9403511 |
| a subunit vaccine based on glycoprotein e2 of bovine virus diarrhea virus induces fetal protection in sheep against homologous challenge. | the primary aim of a bovine virus diarrhea virus (bvdv) vaccine is to prevent transplacental transmission of virus. e2 genes of three bvdv strains, belonging to antigenic groups ia, ib and ii, were expressed in insect cells. three groups of 12 ewes were immunized twice with one of the e2 proteins. a fourth group served as a control. the ewes were served and the pregnant ewes of each vaccination group were allotted to three different challenge groups. seven weeks after the second vaccination the ... | 1997 | 9413105 |
| genomic (5'utr) and serological differences among german bvdv field isolates. | isolates of bovine viral diarrhoea virus (bvdv) collected in germany were examined for their genomic heterogeneity in sequences from the 5'untranslated region (utr) of the viral genome. polymerase chain reaction (pcr) tests based on the 5'utr and the region coding for the ns2-3/4a polypeptide were used to differentiate between bvdv i and bvdv ii genotypes. eleven out of 96 bvdv-isolates were identified as bvdv ii. virus neutralization tests with bvdv i- or ii-specific antisera raised in cattle w ... | 1997 | 9413513 |
| [immunohistochemical studies on organ tropism of different biotypes of bvd virus in experimentally infected sheep fetuses]. | paraffin sections from various organs of sheep fetuses following transplacental infection with non-cytopathogenic (ncp) bovine viral diarrhoea virus (bvdv) or cytopathogenic (cp) bvdv were stained immunohistochemically with bvdv-specific monoclonal antibodies. comparison of the distribution of viral antigen in sections from fetuses of experiment a revealed that in organs such as parotid, thyroid, thymus, lung, spleen, kidney, liver and skin from 20 days post inoculation (p.i.) onwards numerous a ... | 1997 | 9445784 |
| cytotoxic t-lymphocyte responses in cattle infected with bovine viral diarrhea virus. | a system for a reproducible in vitro restimulation of bovine viral diarrhea virus (bvdv)-specific cytotoxic t-cells (ctl) was developed. lymphocyte cultures of bvdv-immunised cattle were stimulated with infectious bvdv isolate pt810 and recombinant bovine interleukin-2 for 12 to 25 days. a specific lysis of concanavalin a-stimulated bvdv-infected autologous target cells was observed, whereas allogeneic bvdv-infected target cells were only marginally lysed as detected by flow cytometry. bvdv-spec ... | 1997 | 9451457 |
| an improved elisa for the detection of serum antibodies directed against classical swine fever virus. | the complex-trapping-blocking (ctb) elisa for detection of antibodies against classical swine fever virus (csfv) using two monoclonal antibodies (mabs) directed against envelope glycoprotein e2, has been improved using recombinant csfv e2-antigen. the newly developed ceditest elisa for csfv-ab is a modification of the ctb-elisa as described by wensvoort et al. (1988) and bloemraad et al. (1993). the old ctb-elisa format comprised of a two-step, single-dilution test which had to be performed by h ... | 1997 | 9460193 |
| experimental mucosal disease of cattle: changes in cell proliferation in lymphoid tissues and intestinal epithelium. | in mucosal disease of cattle, the initial and most severe lesions are found in the lymphoid follicles and intestinal crypts, both sites showing a high cell proliferation rate. in the present study, the changes in the number and distribution of proliferating cells were investigated immunohistologically, by demonstrating the proliferation-associated nuclear antigen, ki-67. tissues were obtained from 30 cattle, all of which had a persistent natural infection with non-cytopathogenic (ncp) bovine vir ... | 1997 | 9502270 |
| photochemical inactivation of viruses and bacteria in platelet concentrates by use of a novel psoralen and long-wavelength ultraviolet light. | a photochemical treatment process has been developed for the inactivation of viruses and bacteria in platelet concentrates. this process is based on the photochemical reaction of a novel psoralen, s-59, with nucleic acids upon illumination with long-wavelength ultraviolet light (uva, 320-400 nm). | 1997 | 9111281 |
| molecular characterization of ovine pestiviruses. | forty-two ovine pestivirus isolates, collected over a period of 18 years, were compared by phylogenetic analysis. the viruses were mostly field isolates from britain; two others originated from sweden and two from new zealand. rt-pcr products were obtained from two genomic regions, one within the 5'-noncoding (5'-nc) region, and the other encompassing parts of the p20 (npro) and c coding regions. direct sequencing of the 5'-nc pcr products, followed by computer-assisted phylogenetic analysis, di ... | 1997 | 9129644 |
| neutralizing antibodies to type 1 and 2 bovine viral diarrhea viruses: detection by inhibition of viral cytopathology and infectivity by immunoperoxidase assay. | neutralizing antibodies to type 1 and 2 bovine viral diarrhea virus (bvdv) strains were measured by a microtiter virus neutralization test (mvnt) in cell culture. antibodies (neutralizing) were detected by inhibition of viral infectivity, by the absence of viral cytopathology for cytopathic strains, or by immunoperoxidase staining for noncytopathic strains. the immunoperoxidase-stained monolayers could be detected without the aid of light microscopy. twenty bvdv strains were used as challenge vi ... | 1997 | 9144381 |
| characterization of the immune response of cattle against non-cytopathic and cytopathic biotypes of bovine viral diarrhoea virus. | cross-infection studies of normal calves infected with homologous pairs of non-cytopathic and cytopathic bovine viral diarrhoea virus (bvdv) showed significant differences in both humoral and cell-mediated immune responses against either biotype over a period of 5 months. serological assays after primary intranasal inoculation showed striking significant (p < 0.05) differences between biotypes. neutralizing titres were detected earlier and were much higher with the non-cytopathic strain than wit ... | 1997 | 9152421 |
| microtiter virus isolation and enzyme immunoassays for detection of bovine viral diarrhea virus in cattle serum. | cattle immunotolerant to and persistently infected (pi) with bovine viral diarrhea (bvd) virus (bvdv) constitute the mechanism by which bvdv persists in cattle herds. two procedures for using serum to detect pi cattle were developed and evaluated. bvdv was found to remain viable for 7 days in serum samples stored at room temperature. the tests use cell culture virus isolation (vi) in 96-well microtiter plates, followed by immunostaining of cell monolayers with monoclonal antibodies. one techniqu ... | 1997 | 9157132 |
| induction of apoptosis and cleavage of poly(adp-ribose) polymerase by cytopathic bovine viral diarrhea virus infection. | the pestivirus bovine viral diarrhea virus (bvdv) causes the fatal diarrheal syndrome, mucosal disease, because of mutations in the viral genome which convert the common noncytopathic (ncp) bvdv into a cytopathic (cp) biotype. we examined the nature of the cytopathic effect of cp-bvdv in cultured bovine cells in order to accurately describe the process and to gain insight into the mechanism of cp-bvdv-induced cell death. the findings demonstrate that cells infected with cp-bvdv in vitro die by a ... | 1997 | 9178501 |
| bovine viral diarrhea virus ns3 serine proteinase: polyprotein cleavage sites, cofactor requirements, and molecular model of an enzyme essential for pestivirus replication. | members of the flaviviridae encode a serine proteinase termed ns3 that is responsible for processing at several sites in the viral polyproteins. in this report, we show that the ns3 proteinase of the pestivirus bovine viral diarrhea virus (bvdv) (nadl strain) is required for processing at nonstructural (ns) protein sites 3/4a, 4a/4b, 4b/5a, and 5a/5b but not for cleavage at the junction between ns2 and ns3. cleavage sites of the proteinase were determined by amino-terminal sequence analysis of t ... | 1997 | 9188600 |
| serine protease of pestiviruses: determination of cleavage sites. | the single-stranded genomic rna of pestiviruses is of positive polarity and encompasses one large open reading frame of about 4,000 codons. the resulting polyprotein is processed co- and posttranslationally by virus-encoded and host cell proteases to give rise to the mature viral proteins. a serine protease residing in the nonstructural (ns) protein ns3 (p80) has been shown to be essential for the release of the ns proteins located downstream of ns3. in this report the ns3 serine protease-depend ... | 1997 | 9188613 |
| phylogenetic analysis of pestiviruses from domestic and wild ruminants. | infections with pestiviruses occur in cattle, sheep, pigs and also in numerous other ungulate species. in the present study, pestiviruses from goat, buffalo, deer and giraffe were analysed at the molecular level; unusual strains from cattle and pigs were also included. a phylogenetic analysis of the respective pestiviruses was undertaken on the basis of a fragment from the 5' noncoding region as well as the gene encoding autoprotease npro. statistical analyses of the respective phylogenetic tree ... | 1997 | 9191930 |
| a 50 kda membrane protein from bovine kidney cells is a putative receptor for bovine viral diarrhea virus (bvdv). | a 50 kda cell surface protein from mdbk cells has been identified as a putative receptor for bovine viral diarrhea virus (bvdv) by using a bvdv specific anti-idiotypic antibody (anti-d89). this study delineates further characterization of the receptor protein. protease treatment of cultured mdbk cells adversely affected the receptor thus abolishing the binding of anti-d89 to the cells. however, pretreatment of the cells with either phospholipases or glycosidases did not signficantly alter the ex ... | 1997 | 9192006 |
| variation from cytopathogenic biotype to non-cytopathogenic biotype is correlated with the deletion of cellular sequence from bovine viral diarrhea viruses. | non-cytopathogenic (ncp) viruses of bovine viral diarrhea (bvd) virus were detected at a low ratio by the reverse plaque formation method from virus samples after several plaque clonings of cytopathogenic (cp) bvd viruses; nadl and osloss strains. this phenomenon suggests that the ncp bvd viruses are produced at a low ratio during the propagation of cp bvd viruses in vitro. to investigate the differences between the parent cp bvd virus and the ncp bvd virus as a real progeny, the regions flankin ... | 1997 | 9192357 |
| expression of envelope protein (e2) of bovine viral diarrhea virus in insect cells. | the gene encoding the envelope glycoprotein (e2) of bovine viral diarrhea virus (bvdv) was expressed in a baculovirus. the expressed protein was detected on the surface of infected cells by immunofluorescence. western blotting analysis showed the presence of the expressed protein of a similar molecular size to the e2 protein. the antigenicity of expressed protein were tested in guinea pigs and cattle. the immunized animals developed neutralizing antibodies against bvdv. | 1997 | 9192369 |
| 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 |
| fetal infection may not be preventable with bvdv vaccines. | 1997 | 9040829 | |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| 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 |
| experimental infection with babesia divergens in cattle persistently infected with bovine virus diarrhoea virus. | nine norwegian red cattle, aged 7-14 months, persistently infected with bovine virus diarrhoea virus (bvdv) were inoculated with a swedish strain of babesia divergens. six persistently infected cattle of the same age and breed were kept as controls. blood and serum samples were collected regularly during the observation period. rectal temperatures were recorded every morning for 25 days post infection, and the animals were examined clinically on a daily basis. sera were examined for antibodies t ... | 1998 | 9673578 |
| alpha-glucosidase inhibitors as potential broad based anti-viral agents. | n-linked oligosaccharides play many roles in the fate and functions of glycoproteins. one function is to assist in the folding of proteins by mediating interactions of the lectin-like chaperone proteins calnexin and calreticulin with nascent glycoproteins. these interactions can be prevented by inhibitors of the alpha-glucosidases and this causes some proteins to be misfolded and retained within the endoplasmic reticulum. in human immunodeficiency virus (hiv) and hepatitis b virus (hbv) the misf ... | 1998 | 9678587 |
| bovine viral diarrhoea virus induces apoptosis in blood mononuclear cells by a mechanism largely dependent on monocytes. | the induction of apoptosis by bovine viral diarrhoea virus (bvdv) was examined in bovine peripheral blood mononuclear cells (pbmc) incubated with an antigenically homologous pair of non-cytopathic and cytopathic bvdv. our results show that the cytopathic biotype, in contrast to the non-cytopathic counterpart, induces apoptosis in pbmc. flow cytometry analysis of cells undergoing apoptosis revealed that: (1) monocytes constitute the major cell population undergoing apoptosis; (2) cytopathic virus ... | 1998 | 9680138 |
| 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 |