Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| vaccination of cattle against bovine viral diarrhoea. | this brief review describes types and quality (efficacy and safety) of bovine viral diarrhoea virus (bvdv) vaccines that are in the market or under development. both conventional live and killed vaccines are available. the primary aim of vaccination is to prevent congenital infection, but the few vaccines tested are not highly efficacious in this respect, as shown in vaccination-challenge experiments. vaccination to prevent severe postnatal infections may be indicated when virulent bvdv strains ... | 1999 | 10028171 |
| foetal cross-protection experiments between type 1 and type 2 bovine viral diarrhoea virus in pregnant ewes. | a flock of 82 non-pregnant ewes was split into three immunisation groups and given an intranasal dose of either cell culture medium, or a type 1 or a type 2 bovine viral diarrhoea virus (bvdv-1 or bvdv-2). two months later the flock was reconstituted and after a further three weeks, the ewes were bred to pestivirus negative rams after synchronisation of oestrus using progesterone sponges. fifty-five ewes were segregated into three challenge groups, each of which comprised ewes from different imm ... | 1999 | 10028172 |
| principles for eradication of bovine viral diarrhoea virus (bvdv) infections in cattle populations. | systematic eradication of bvdv without vaccination started in scandinavia in 1993. in principle, the schemes include; (1) identification of non-infected and infected herds using different combinations of serological herd tests such as bulk milk tests and spot tests (sample of animals in a certain age), (2) monitoring/certification of non-infected herds by repeated sampling, applying one of the above-mentioned methods and (3) virus clearance in infected herds aimed at removing persistently infect ... | 1999 | 10028173 |
| prevalence and geographic distribution of bovine viral diarrhoea (bvd) infection in finland 1993-1997. | bulk milk samples from every herd supplying milk to dairies in finland were examined for the presence of antibodies to bvd virus (bvdv) annually during 1993-1997. the highest prevalence, 0.99% in 1994, declined to 0.37% in 1996; however, this favourable trend appeared to discontinue in 1997, where the prevalence remained at 0.41%. in 1993, sera of all individual animals from bulk milk antibody-positive herds were examined for the presence of these antibodies. since 1994, only sera of animals fro ... | 1999 | 10028175 |
| bovine virus diarrhoea (bvd) control programme in an area in the rome province (italy). | a bvd control programme based on the identification and removal of persistently infected (pi) animals is being undertaken in an area in the rome province, where bvd outbreaks had been previously detected. it involves 174 mainly dairy herds, from which blood samples of all bovines older than 1 year are obtained through the national brucellosis and leukosis eradication programme. samples sufficient to detect the presence of seropositive animals at a prevalence of 5% or more are initially screened ... | 1999 | 10028176 |
| study on prevalence of bovine viral diarrhoea virus (bvdv) antibodies in 29 italian dairy herds with reproductive problems. | an epidemiological survey on prevalence distribution of antibodies to bvdv was carried out in dairy cattle herds during 1995-1996 in northern italy. a total of 704 serum samples from 29 non-vaccinated herds reported to have reproductive problems were tested for serum neutralising antibodies. in each herd, sampling was based on the stratification by age into five classes (< 6 months old calves, 6-12 months old calves, pregnant heifers, uniparous, pluriparous). overall, 53.3% of samples were serol ... | 1999 | 10028177 |
| prevalence of bovine viral diarrhea virus infection in bulls in artificial insemination centers in poland. | this study was directed at the evaluation of the prevalence of bovine viral diarrhea virus (bvdv) infection in bulls in artificial insemination centers. both serological and virological examinations were performed. blood samples were tested in micro-seroneutralization test for bvdv antibodies. virus isolation was performed in cell culture and bvdv antigen was detected in an indirect immunofluorescence assay with monoclonal antibodies. one hundred and seventy-five serum samples and 219 whole bloo ... | 1999 | 10028178 |
| bovine viral diarrhoea (bvd) infections--control and eradication programme in breeding herds in slovenia. | a slovenian bvd control and eradication programme was initiated in 1994, and the results from testing of bovine herds for antigen and antibodies in 1996 are presented. samples originating from breeding herds, breeding herds for young bulls, and insemination stations were tested by antigen or antibody elisa, or by pcr. out of 7968 samples from 354 herds we found 18% of the animals antibody-positive. in one region situated in the north-east of slovenia we found the herds to be almost nearly free o ... | 1999 | 10028179 |
| genetic heterogeneity of porcine and ruminant pestiviruses mainly isolated in japan. | the genetic variability of porcine and ruminant pestiviruses was studied by comparative nucleotide sequence analysis of 73 isolates (42 porcine and 31 ruminant), including 65 japanese isolates (35 porcine and 30 ruminant). the 5'-untranslated region (utr) amplified by reverse transcriptase-polymerase chain reaction (rt-pcr) was determined by direct sequencing and phylogenetic analysis was performed from the nucleotide sequence data. most porcine isolates were divided into two major subgroups, cl ... | 1999 | 10068129 |
| level and duration of serum antibodies in cattle infected experimentally and naturally with bovine virus diarrhoea virus. | neutralising serum antibodies against bovine virus diarrhoea virus (bvdv) were monitored for three years in 35 cattle that were infected with the virus as calves; 24 of the calves were inoculated intramuscularly or intranasally, and 11 contracted the infection naturally. all the experimentally infected calves seroconverted within 14 to 28 days after inoculation, and all the animals still had high serum levels of antibodies to bvdv three years after infection. determinations of antibody levels in ... | 1999 | 10070699 |
| association of non-cytopathogenic bvdv with bovine blastocysts: effects of washing, duration of viral exposure and degree of blastocyst expansion. | 1999 | 10074663 | |
| induction of humoral and cellular immune responses in mice by a recombinant fowlpox virus expressing the e2 protein of bovine viral diarrhea virus. | a recombinant fowlpox virus (rfpv/e2) expressing the e2 protein of bovine viral diarrhea virus (bvdv) was constructed and characterized. mice were immunized with recombinant virus and both humoral and cellular immune responses were studied. rfpv/e2 induced bvdv-specific antibodies which were detected by elisa. in addition, mouse sera were shown to neutralize bvdv. a cytokine elisa assay revealed that mice vaccinated with rfpv/e2 induced 7-fold more interferon-gamma than parental fowlpox virus. | 1999 | 10077834 |
| expression of the e2 envelope glycoprotein of bovine viral diarrhoea virus (bvdv) elicits virus-type specific neutralising antibodies. | a region of genome from the nadl strain of bvdv corresponding to the coding sequence for the e2 glycoprotein has been molecularly cloned using rt-pcr. the viral cdna sequence was used to construct vaccinia virus recombinants that expressed either the entire e2 coding sequence or fragments of it. these recombinants were used to immunise mice of three h-2 haplotypes to investigate their ability to elicit a neutralising antibody response against bvdv. sera from mice immunised with the recombinant e ... | 1999 | 10078593 |
| production of a highly immunogenic subunit iscom vaccine against bovine viral diarrhea virus. | bovine viral diarrhea virus (bvdv) is a major pathogen of cattle in most countries. the main reservoir of virus in herds are bvdv persistently infected animals, which arise as a result of infection of the bovine fetus early in gestation. the spread of virus to the unborn fetus may be prevented by vaccination of the dam. we describe in this report the production and initial testing of an inactivated subunit vaccine against bvdv. the vaccine is based on production of antigen in primary bovine cell ... | 1999 | 10195615 |
| cross-protective efficacy of a bovine viral diarrhea virus (bvdv) type 1 vaccine against bvdv type 2 challenge. | a new genotype of bovine viral diarrhea virus (bvdv), designated bvdv type 2 (bvdv 2), has become prevalent in the field. bvdv 2 strains are antigenically distinct from currently available vaccine strains of the bvdv 1 genotype, raising concerns about cross-protection of these vaccines against bvdv 2 challenge. to determine cross-protective efficacy of a modified-live virus (mlv) vaccine containing bvdv 1 strain wrl (bvdv 1(wrl)), two studies were conducted in which the relative magnitude and du ... | 1999 | 10195622 |
| sequence and structural elements at the 3' terminus of bovine viral diarrhea virus genomic rna: functional role during rna replication. | bovine viral diarrhea virus (bvdv), a member of the genus pestivirus in the family flaviviridae, has a positive-stranded rna genome consisting of a single open reading frame and untranslated regions (utrs) at the 5' and 3' ends. computer modeling suggested the 3' utr comprised single-stranded regions as well as stem-loop structures-features that were suspected of being essentially implicated in the viral rna replication pathway. employing a subgenomic bvdv rna (di9c) that was shown to function a ... | 1999 | 10196256 |
| virus reduction in the preparation of intravenous immune globulin: in vitro experiments. | while immune globulins for intravenous administration (igiv) have an excellent record with respect to virus safety, concern regarding these preparations has been raised by reports of transmission of hepatitis c virus (hcv) to patients treated with igiv and the presence of genetic material for hcv in igiv preparations. | 1999 | 10204586 |
| de novo initiation of rna synthesis by a recombinant flaviviridae rna-dependent rna polymerase. | recombinant rna-dependent rna polymerases have been reported to synthesize rnas by extending from the 3' hydroxyl of a template or an oligonucleotide primer. de novo initiation has not been reported. establishment of such an assay would facilitate the analysis of the initiation requirements and allow the testing of antiviral compounds specifically targeting initiation. using chemically synthesized rnas and dnas, we demonstrate that the recombinant rna-dependent rna polymerase (ns5b) of bovine vi ... | 1999 | 9887312 |
| synergistic effects of bovine respiratory syncytial virus and non-cytopathic bovine viral diarrhea virus infection on selected bovine alveolar macrophage functions. | the effect of bovine respiratory syncytial virus (brsv) and non-cytopathic bovine viral diarrhea virus (ncpbvdv) infection on selected bovine alveolar macrophage (am) functions was investigated. alveolar macrophages were harvested from 2- to 6-month-old calves seronegative for brsv and bvdv and inoculated with approximately 1 median cell culture infective dose of virus per am. control, brsv infected, ncpbvdv-infected and brsv-ncpbvdv coinfected am cultures were evaluated for fc receptor expressi ... | 1999 | 9918333 |
| seroepidemiology of undifferentiated fever in feedlot calves in western canada. | the relationships between 4 bacterial and 3 viral antibody titers and morbidity (undifferentiated fever (uf)) and mortality were investigated in recently weaned beef calves. blood samples from 100 animals that required treatment for uf (cases) and 100 healthy control animals (controls) were obtained: upon arrival at the feedlot (arrival), at the time of selection as a case or control (selection), and at approximately 33 d of the feeding period (convalescent). seroconversion to pasteurella haemol ... | 1999 | 9919366 |
| correlation between point mutations in ns2 and the viability and cytopathogenicity of bovine viral diarrhea virus strain oregon analyzed with an infectious cdna clone. | cytopathogenicity of bovine viral diarrhea virus (bvdv) is correlated with expression of the nonstructural protein ns3, which can be generated by processing of a fusion protein termed ns2-3. for the cytopathogenic (cp) bvdv strain oregon, ns2-3 processing is based on a set of point mutations within ns2. to analyze the correlation between ns2-3 cleavage and cytopathogenicity, a full-length cdna clone composed of cdna from bvdv oregon and the utmost 5'- and 3'-terminal sequences of a published inf ... | 2000 | 10590128 |
| influence of new infection with bovine virus diarrhoea virus on udder health in norwegian dairy cows. | a retrospective longitudinal study was conducted to examine whether the exposure of dairy herds to bovine virus diarrhoea virus (bvdv) affected udder health. all norwegian dairy herds that had experienced a marked increase in the bvdv antibody titres in bulk milk (from a level corresponding to an optical density (od) <0.25 to >0.55, as determined by an indirect enzyme-linked immunosorbent assay) between two nation-wide herd screening examinations carried out late in 1992 and 1993, respectively, ... | 2000 | 10673059 |
| birth of a bvdv-free calf from a persistently infected embryo transfer donor. | 2000 | 10678813 | |
| typing of pestiviruses from eland in zimbabwe. | pestiviruses were isolated from three eland (taurotragus oryx) in zimbabwe. the viruses were characterised by typing with monoclonal antibodies and by partial genetic sequencing. all were similar to bovine viral diarrhea viruses commonly isolated from cattle. this suggests that bovine viral diarrhea virus can spread from cattle to eland. | 2000 | 10682761 |
| ultrastructural changes in follicles of small-intestinal aggregated lymphoid nodules in early and advanced phases of experimentally induced mucosal diseases in calves. | to investigate ultrastructural changes in follicles of small-intestinal aggregated lymphoid nodules (peyer's patches) of calves with early and advanced phases of experimentally induced mucosal disease (md). | 2000 | 10685690 |
| strategies for evaluation of enveloped virus inactivation in red cell concentrates using hypericin. | photodynamically induced virus inactivation appears promising in preventing transmission of enveloped virus infections in transfusible blood products. the potential for utilizing hypericin as a photosensitizer to inactivate key enveloped viruses in packed red cell concentrates (prc) was evaluated. in addition to inactivating effectively > or = 10(6) tcid50 of human immunodeficiency virus (hiv), inactivation of bovine viral diarrhea virus (bvdv) in prc was used as a model for hepatitis c virus to ... | 2000 | 10687393 |
| bovine viral diarrhea virus cytopathic and noncytopathic biotypes and type 1 and 2 genotypes in diagnostic laboratory accessions: clinical and necropsy samples from cattle. | one hundred three bovine samples submitted to the oklahoma animal disease diagnostic laboratory (oaddl) that were positive for bovine viral diarrhea virus (bvdv) were typed by a nested reverse transcription-polymerase chain reaction for bvdv genotypes. these bvdv samples included supernatants from virus isolation (79), serums (17), and buffy coats (7). the biotype, cytopathic (cp) or noncytopathic (ncp), was determined by cell culture virus isolation. twenty-eight of 103 samples were submitted f ... | 2000 | 10690773 |
| neospora caninum and bovine virus diarrhoea virus infections in swedish dairy cows in relation to abortion. | the protozoan parasite neospora caninum and bovine virus diarrhoea virus (bvdv) are recognized as important causes of bovine abortion and congenital disease worldwide. in this study, serological investigations were performed to estimate the prevalence of n. caninum infection in swedish dairy cattle, to assess to what extent it may affect abortion rates, and to determine possible effects of coinfection with bvdv. the overall n. caninum seroprevalence in swedish dairy cows was estimated at 2% (16/ ... | 2000 | 10712809 |
| broad-spectrum antiviral activity of the imp dehydrogenase inhibitor vx-497: a comparison with ribavirin and demonstration of antiviral additivity with alpha interferon. | the enzyme imp dehydrogenase (impdh) catalyzes an essential step in the de novo biosynthesis of guanine nucleotides, namely, the conversion of imp to xmp. the major event occurring in cells exposed to competitive impdh inhibitors such as ribavirin or uncompetitive inhibitors such as mycophenolic acid (mpa) is a depletion of the intracellular gtp and dgtp pools. ribavirin is approved as an inhaled antiviral agent for treatment of respiratory syncytial virus (rsv) infection and orally, in combinat ... | 2000 | 10722482 |
| structural aspects of the zona pellucida of in vitro-produced bovine embryos: a scanning electron and confocal laser scanning microscopic study. | structural aspects of the bovine zona pellucida (zp) of in vitro-matured (ivm) oocytes and in vitro-produced (ivp) embryos were studied in two experiments to find a tentative explanation for the zona's barrier function against viral infection. in experiment 1, the ultrastructure of the outer zp surface was studied. the diameter (nm) and the number of the outer pores within an area of 5000 microm(2) of 10 ivm oocytes, 10 zygotes, 10 8-cell-stage embryos, and 10 morulae were evaluated by scanning ... | 2000 | 10642588 |
| the rna helicase and nucleotide triphosphatase activities of the bovine viral diarrhea virus ns3 protein are essential for viral replication. | helicase/nucleoside triphosphatase (ntpase) motifs have been identified in many rna virus genomes. similarly, all the members of the flaviviridae family contain conserved helicase/ntpase motifs in their homologous ns3 proteins. although this suggests that this activity plays a critical role in the viral life cycle, the precise role of the helicase/ntpase in virus replication or whether it is essential for virus replication is still unknown. to determine the role of the ns3 helicase/ntpase in the ... | 2000 | 10644352 |
| interactions of bovine viral diarrhoea virus glycoprotein e(rns) with cell surface glycosaminoglycans. | recombinant e(rns) glycoprotein of bovine viral diarrhoea virus (bvdv) has been tagged with a marker epitope or linked to an immunoglobulin fc tail and expressed in insect and mammalian cell lines. the product was shown to be functional, both having ribonuclease activity and binding to a variety of cells that were permissive and non-permissive for replication of bvdv. addition of soluble e(rns) to the medium blocked replication of bvdv in permissive cells. binding of epitope-tagged e(rns) to per ... | 2000 | 10644844 |
| antigenic characterization of bovine viral diarrhoea virus isolates from spain with a panel of monoclonal antibodies. | a group of 47 bovine viral diarrhoea virus (bvdv) strains isolated from a variety of bovine tissues from eight different geographical areas of spain and two bvdv strains isolated from a cell line were characterized antigenically with a panel of 23 monoclonal antibodies (mabs). the mabs were directed at one of three viral proteins: e2, erns and ns2-3. a peroxidase-linked assay was used to test the mabs for reactivity against infected cell monolayers. the data were analysed by two computational me ... | 2000 | 11244871 |
| diagnosis of persistent bovine viral diarrhea virus infection by immunohistochemical staining of formalin-fixed skin biopsy specimens. | the objective of this study was to evaluate the efficacy of immunohistochemical (ihc) staining for diagnosis of persistent bovine viral diarrhea virus (bvdv) infection using formalin-fixed, paraffin-embedded skin biopsy specimens. skin from 41 of 42 calves shown to be persistently infected (pi) with bvdv by repeated virus isolation more than 3 weeks apart were immunohistochemically positive for bvdv antigen. positive ihc staining was most pronounced in the keratinocytes and in hair follicle epit ... | 2000 | 11021424 |
| malignant catarrhal fever: polymerase chain reaction survey for ovine herpesvirus 2 and other persistent herpesvirus and retrovirus infections of dairy cattle and bison. | using a polymerase chain reaction (pcr) test for sequences of ovine herpesvirus 2 (ohv2), this virus was shown to be significantly associated with sheep-associated malignant catarrhal fever (sa-mcf) in terminal cases of disease in 34 cattle and 53 bison. ovine herpesvirus 2 was not detected in cattle (38) and bison (10) that succumbed to other diseases. other persistent herpesviruses, retroviruses, and pestivirus, some of which have been previously isolated from cases of sa-mcf, were not associa ... | 2000 | 11021426 |
| single amino acid differences are sufficient for cd4(+) t-cell recognition of a heterologous virus by cattle persistently infected with bovine viral diarrhea virus. | cattle that are persistently infected (pi) with one strain of bovine viral diarrhea virus (bvdv) can resolve infection with a second, antigenically heterologous strain but not the homologous strain. since cd4(+) t cells are thought to be critical for the resolution of acute bvdv infection (howard et al., 1992, vet. immunol. immunopathol. 32, 303-314), we have examined the recognition of a heterologous virus (nadl) by cd4(+) t cells from pe515-pi animals. the immune response of non-pi control cat ... | 2000 | 11021996 |
| evolution of viruses by acquisition of cellular rna or dna nucleotide sequences and genes: an introduction. | the origins of virus evolution may be traced to archeabacteria since inouye and inouye (6) discovered a retroelement with a gene for reverse transcriptase in the bacterial genome and in the satellite, multiple copy single stranded dna (msdna) in the soil bacterium myxococcus xanthus. it was possible (8) to define the evolution of retroelements in eukaryotic cells of plants, insects (gypsy retrovirus) and vertebrates. the replication of rna viruses in eukaryotic cells allowed for the viral rna ge ... | 2000 | 11022785 |
| chimeric classical swine fever viruses containing envelope protein e(rns) or e2 of bovine viral diarrhoea virus protect pigs against challenge with csfv and induce a distinguishable antibody response. | three chimeric classical swine fever virus (csfv)/bovine viral diarrhoea virus (bvdv) full-length dna copies were constructed, based on the infectious dna copy of the csfv vaccine strain c. the antigenic region of e2 and/or the complete e(rns) gene were replaced by the analogous sequence of bvdv ii strain 5250. viable chimeric virus flc11, in which e(rns) was replaced, was directly recovered from supernatant of sk6.t7 cells transfected with full-length dna. viable chimeric virus flc9, in which e ... | 2000 | 11027808 |
| the genetic basis for cytopathogenicity of pestiviruses. | two biotypes of pestiviruses, cytopathogenic (cp) and noncp viruses, can be distinguished by their effects on tissue culture cells. identification of cp bovine viral diarrhea virus (bvdv) has been frequently reported since antigenically closely related noncp and cp bvdv can be isolated from cattle with fatal mucosal disease (md) and are called a virus pair. in contrast to the bvdv system, only few cp border disease virus (bdv) and cp classical swine fever virus (csfv) strains have been described ... | 2000 | 11042405 |
| cellular insertions in the ns2-3 genome region of cytopathic bovine viral diarrhoea virus (bvdv) isolates. | when compared to noncytopathic (ncp) bovine viral diarrhoea virus (bvdv), some cytopathic (cp) bvdv contain additional sequences in the ns2-3 genomic region. one of these insertions, which is 270 nucleotides long and of host origin (cins), was first described for strain nadl. to find out how frequently this type of insertion occurs in other cp bvdv, 32 cp bvdv field isolates and the bvdv reference cp strain indiana were screened using rt-pcr which detected cins in nadl. for most cp viruses an rt ... | 2000 | 11042406 |
| phylogenetic, antigenic and clinical characterization of type 2 bvdv from north america. | bovine viral diarrhea virus (bvdv) infection continues to have a significant impact upon us cattle producers despite the availability of more than 140 federally licensed vaccines. detection and control is hampered by viral heterogeneity that results in differences in neutralizing epitopes, cytopathology and virulence. recently it was found that there are two different genotypes, bvdv1 and bvdv2, among bvdv. bvdv2 isolates make up a significant proportion of the bvdv isolated in north america. se ... | 2000 | 11042408 |
| morphologic lesions in type 2 bvdv infections experimentally induced by strain bvdv2-1373 recovered from a field case. | widespread outbreaks of severe acute bvdv, some associated with hemorrhagic syndrome (hs), were reported in quebec and ontario in 1993. these outbreaks caused significant economic hardship in infected herds. in the ontario outbreak 150 dairy, 600 beef and 100 milk and grain fed veal herds were affected with losses estimated at $40000-$10000 per herd in lost animals, milk production, abortions and genetics. fever, pneumonia, diarrhea, and sudden death occurred in all age groups of cattle. abortio ... | 2000 | 11042409 |
| comparative investigation of tissue alterations and distribution of bvd-viral antigen in cattle with early onset versus late onset mucosal disease. | tissue alterations and distribution of bvdv antigen were examined in nine cattle with early onset and five cattle with late onset mucosal disease (md) to evaluate the possibility to differentiate between the two disease entities. md was induced by inoculation of persistently viremic cattle with different strains of cytopathogenic bvdv. animals which developed early onset md became moribund approximately 2 weeks post-inoculation (pi); animals with late onset md 42-115 days pi. all animals were eu ... | 2000 | 11042410 |
| clinical, pathological and antigenic aspects of bovine viral diarrhea virus (bvdv) type 2 isolates identified in brazil. | nucleotide sequencing and phylogenetic analysis of brazilian bovine viral diarrhea virus (bvdv) field isolates identified four viruses belonging to the genotype 2. comparison of 5' utr sequences from these isolates to those of north american bvdv type 2 revealed genomic variations that correlated with the geographic origins of the isolates. two of the brazilian type 2 viruses were isolated from clinical cases of gastroenteric/respiratory disease and two were isolated from healthy bovine fetuses. ... | 2000 | 11042411 |
| bovine viral diarrhoea virus: its effects on ovarian function in the cow. | bovine viral diarrhoea virus (bvdv) is a major cattle pathogen responsible for a spectrum of symptoms, including reproductive failure. in this paper we investigate how bvdv interacts with the ovary. the viruses' tropism for the pre-ovulatory oocyte was studied by indirect immunohistochemistry. two monoclonal antibodies, raised against the non-structural protein ns3 and the envelope glycoprotein e2 were used to probe cryo-sections cut from the ovaries of three persistently infected heifers. ns3 a ... | 2000 | 11042412 |
| a new inactivated bvdv genotype i and ii vaccine. an immunisation and challenge study with bvdv genotype i. | an inactivated vaccine containing bvdv i and ii strains (pt810; bvdv i, and 890; bvdv ii) and using different adjuvants and antigen dosages was tested in a cattle challenge model. groups of six healthy, seronegative cattle were vaccinated twice with a low dose (10(6.6) tcid(50) pt810 and 10(7.2) tcid(50) 890) vaccine with the adjuvant bay r1005 or a high dose (10(7.8) tcid(50) pt810 and 10(8. 2) tcid(50) 890) vaccine with two different adjuvants (bay r1005 or polygen). thirty-eight days after th ... | 2000 | 11042413 |
| development of a fetal challenge method for the evaluation of bovine viral diarrhea virus vaccines. | a method to evaluate the efficacy of bovine viral diarrhea virus (bvdv) vaccines using a multiple challenge model was investigated. four pregnant heifers were challenged intranasally with a type i and type ii isolate of bvdv at 75 days of gestation. at 60 days postinoculation, virus isolation and rt-pcr from blood and tissues of fetuses indicated that all fetus were persistently infected with both type i and type ii isolates. differing results of detection by pcr and virus isolation between the ... | 2000 | 11042414 |
| translation from the internal ribosome entry site of bovine viral diarrhea virus is independent of the interaction with polypyrimidine tract-binding protein. | translation of the pestiviral polyprotein is initiated cap independently at an internal site of the viral rna, the internal ribosome entry site (ires). we investigated the translation from the ires of bovine viral diarrhea virus (bvdv) and the possible interaction of the unconventional cellular rna-binding proteins, particularly of polypyrimidine tract-binding protein (ptb). the bvdv ires is translationally active in rabbit reticulocyte lysate (rrl), and it is translated most efficiently at low ... | 2000 | 11042415 |
| template nucleotide moieties required for de novo initiation of rna synthesis by a recombinant viral rna-dependent rna polymerase. | the recombinant rna-dependent rna polymerase of the bovine viral diarrhea virus specifically requires a cytidylate at the 3' end for the de novo initiation of rna synthesis (c. c. kao, a. m. del vecchio, and w. zhong, virology 253:1-7, 1999). using rnas containing nucleotide analogs, we found that the n3 and c4-amino group at the initiation cytidine were required for rna synthesis. however, the ribose c2'-hydroxyl of the initiating cytidylate can accept several modifications and retain the abili ... | 2000 | 11044075 |
| differences in experimental virulence of bovine viral diarrhoea viral strains isolated from haemorrhagic syndromes. | in the late 1980s, a new hypervirulent and epidemic form of bovine viral diarrhoea virus (bvdv) infection appeared in north america. a similar but sporadic syndrome was later reported in europe. to compare the pathogenic characters of the north american and european hypervirulent strains, we inoculated bvdv naïve calves with bvdv strains isolated from haemorrhagic syndromes originating in belgium, france and the usa. the experimental procedure comprised daily clinical examination and measurement ... | 2000 | 11061962 |
| a universal 'one-tube' rt-pcr protocol for amplifying isolates of bovine viral diarrhoea virus. | the increase in the knowledge of the genetic variability of bvdv and the identification of some of the genetic determinants of its pathogenicity require robust and practical tools for rapid molecular characterization of the various genotypes of this virus. this study was undertaken to develop a standard protocol for rt-pcr that allows the amplification of various parts of the genome of bvdv without the need for optimizing each individual reaction. the reaction set-up is very flexible because it ... | 2000 | 11085469 |
| properties of the bovine viral diarrhoea virus replicase in extracts of infected mdbk cells. | an assay for the bovine viral diarrhoea virus (bvdv) replicase was developed using extracts from bvdv-infected cells. the replicase activity was maximal approximately 8 h post-infection as measured by the generation of a genomic length radiolabelled rna. using a semi-denaturing gel system, three virus-specific in vitro radiolabelled nascent rna species were identified. a fast-migrating rna was demonstrated to be the double-stranded replicative form (rf). a second form was shown to be a partially ... | 2000 | 11087098 |
| deletions of structural glycoprotein e2 of classical swine fever virus strain alfort/187 resolve a linear epitope of monoclonal antibody wh303 and the minimal n-terminal domain essential for binding immunoglobulin g antibodies of a pig hyperimmune serum. | the major structural glycoprotein e2 of classical swine fever virus (csfv) is responsible for eliciting neutralizing antibodies and conferring protective immunity. the current structural model of this protein predicts its surface-exposed region at the n terminus with a short stretch of the c-terminal residues spanning the membrane envelope. in this study, the n-terminal region of 221 amino acids (aa) covering aa 690 to 910 of the csfv strain alfort/187 e2, expressed as a fusion product in escher ... | 2000 | 11090160 |
| production and characterization of monoclonal antibodies to brazilian isolates of bovine viral diarrhea virus. | three brazilian isolates of bovine viral diarrhea virus (bvdv), antigenically distinct from the standard north american isolates, were selected to immunize balb/c mice in order to obtain hybridoma cells secreting anti-bvdv monoclonal antibodies (mabs). two hybridoma clones secreting mabs, reacting specifically with bvdv-infected cells (mabs 3.1c4 and 6.f11), were selected after five fusions and screening of 1001 hypoxanthine-aminopterin-thymidine-resistant clones. these mabs reacted in an indire ... | 2000 | 11105099 |
| bovine viral diarrhea virus in new world camelids. | a virus known to cause multiple problems in cattle, bovine viral diarrhea virus, was isolated from 3 different cases in new world camelids. virus isolation, immunoperoxidase staining, and fluorescent antibody staining were used to detect the virus. the herds involved were screened for antibody titers to bovine viral diarrhea and virus isolation from the buffy coat. bovine viral diarrhea virus should be considered as a cause of death in young and old new world camelids. | 2000 | 11108460 |
| recombinant bovine adenovirus type 3 expressing bovine viral diarrhea virus glycoprotein e2 induces an immune response in cotton rats. | recombinant bovine adenovirus is being developed as a live vector for animal vaccination and for human gene therapy. in this study, two replication-competent bovine adenovirus 3 (bav-3) recombinants (bav331 and bav338) expressing bovine viral diarrhea virus (bvdv) glycoprotein e2 in the early region 3 (e3) of bav-3 were constructed. recombinant bav331 contains chemically synthesized e2 gene (nucleotides modified to remove internal cryptic splice sites) under the control of bav-3 e3/major late pr ... | 2000 | 11112498 |
| insertion of cellular nedd8 coding sequences in a pestivirus. | for the cytopathogenic (cp) bovine viral diarrhea virus (bvdv) strain cp 821, a duplication of the genomic region encoding part of ns2, ns3, ns4a, and part of ns4b together with a nonviral insertion was detected. further analyses including molecular cloning and sequencing of the putative cellular recombination partner showed that the insertion in cp 821 originated from a bovine mrna encoding the cellular protein nedd8, which is 58% identical to ubiquitin. to our knowledge the genome of cp 821 re ... | 2000 | 11118368 |
| replication and persistence of different strains of bovine viral diarrhea virus in an in vitro embryo production system. | recent studies have shown that exposed, in vitro-derived embryos remain contaminated with bovine viral diarrhea virus (bvdv) after washing. however, introduction of a genotype ii versus genotype i strain of bvdv into an ivf system was reported to provide greater potential for transmission of disease. the primary objective of this study was to compare the potentials for different strains of noncytopathic bvdv to replicate in an ivf system, associate with ivf embryos and infect co-cultured cells v ... | 2000 | 11131328 |
| cd4(+) t-cell responses to bovine viral diarrhoea virus in cattle. | friesian calves were infected with one of three isolates of bovine viral diarrhoea virus (bvdv) and used to establish parameters for an in vitro model of bvdv-reactive t-cell responses in cattle. the study assessed virus clearance, seroconversion, maturation of lymphoproliferative responses (both during and following disease resolution) and the antigen-specificity of cd4(+) t cells from recovered animals. seroconversion and virus-specific lymphoproliferation were not detected until viraemia had ... | 2000 | 10773320 |
| clinical response and immunomodulation following experimental challenge of calves with type 2 noncytopathogenic bovine viral diarrhea virus. | eight calves between 16 and 18 weeks of age that were seronegative to bovine viral diarrhea virus (bvdv), bovine leucosis virus and bovine immunodeficiency-like virus were infected (day 0) intranasally with the type 2 noncytopathogenic canadian 24515 field isolate of bvdv in order to evaluate the effect of bvdv infection on certain clinical, hematological and immunological parameters. all virus-exposed animals developed fever and showed a significant (p < 0.05, 0.01 or 0.001) drop in the number ... | 2000 | 10779200 |
| [contamination of bovine fetal serum with bovine viral diarrhea virus]. | fetal bovine serum (fbs) used in cell culture may be contaminated with viruses, among them bovine viral diarrhea virus (bvdv) affecting the production of biological reagents and the results of diagnosis. the filtration process used in the preparation of commercial fbs abrogates most viral agents that may be present in raw fbs, but bvdv may pass through the filters because of its small size and its pleomorphism. while detection of bovine herpes virus-1 and parainfluenza-3 (pi-3) is determined by ... | 2000 | 10785940 |
| viral contamination of embryos cryopreserved in liquid nitrogen. | despite the worldwide application of embryo-freezing technology as the means of preserving germplasm of mammalian species, there is no information available on the possible transmission of infectious agents to cryopreserved embryos via contaminated liquid nitrogen (ln). recently, it has been reported that new methods of cryopreservation which employ ultrarapid freezing or vitrification require direct contact between the freezing medium containing oocytes or embryos and liquid phase nitrogen (lpn ... | 2000 | 10788310 |
| photochemical decontamination of red blood cell concentrates with the silicon phthalocyanine pc 4 and red light. | various approaches are being developed for virus inactivation of red blood cell concentrates (rbcc) in order to increase the safety of the blood supply. we have been studying the silicon phthalocyanine pc 4 for this purpose, a photosensitizer activated with red light. pc 4 targets the envelope of pathogenic viruses such as hiv. to protect rbc during the process two main approaches are used: (i) inclusion of quenchers of reactive oxygen species produced during the treatment. tocopherol succinate ... | 2000 | 10794102 |
| evaluation of vaccines, interferons and cell substrates for pestivirus contamination. | pestiviruses are potential contaminants of biological products produced in bovine or porcine cells or manufactured via processes using animal-derived raw materials such as bovine serum. in order to investigate possible contamination of products including those manufactured and/or licensed in the us, 38 lots of viral vaccines and five lots of interferon alpha (ifnalpha) were tested by reverse transcriptase polymerase chain reaction (rt-pcr) for the presence of bovine viral diarrhoea virus (bvdv). ... | 2000 | 10799055 |
| pooled-sample testing as a herd-screening tool for detection of bovine viral diarrhea virus persistently infected cattle. | the study was conducted to develop methodology for least-cost strategies for using polymerase chain reaction (pcr)/probe testing of pooled blood samples to identify animals in a herd persistently infected with bovine viral diarrhea virus (bvdv). cost was estimated for 5 protocols using monte carlo simulations for herd prevalences of bvdv persistent infection (bvdv-pi) ranging from 0.5% to 3%, assuming a cost for a pcr/probe test of $20. the protocol associated with the least cost per cow involve ... | 2000 | 10826831 |
| a case report: evidence for type 2 bovine viral diarrhea virus (bvdv)-associated disease in beef herds vaccinated with a modified-live type 1 bvdv vaccine. | 2000 | 10826842 | |
| the effects of bovine viral diarrhoea virus on cattle reproduction in relation to disease control. | bovine viral diarrhoea virus (bvdv) is a major reproductive pathogen in cattle. infection of the bull can lead to a fall in semen quality and the isolation of infectious virus in the ejaculate, while infection in the cow leads to poor conception rates, abortions and congenital defects. bvdv also reduces the animal's resistance to other respiratory and enteric pathogens. the prevalence of bvdv is primarily due to the efficiency with which the virus crosses the placenta of susceptible females. cal ... | 2000 | 10844229 |
| a stem-loop motif formed by the immediate 5' terminus of the bovine viral diarrhea virus genome modulates translation as well as replication of the viral rna. | bovine viral diarrhea virus (bvdv), a pestivirus member of the flaviviridae family, has a positive-stranded rna genome which consists of a single open reading frame (orf) and untranslated regions (utrs) at the 5' and 3' ends. the 5' utr harbors extensive rna structure motifs; most of them were shown to contribute to an internal ribosomal entry site (ires), which mediates cap-independent translation of the orf. the extreme 5'-terminal region of the bvdv genome had so far been believed not to be r ... | 2000 | 10846062 |
| experimental inoculation of calves with laboratory strains of bovine viral diarrhea virus. | diarrhea, erosions and ulcers of the oral mucosa, with conjunctival and nasal discharges, were observed in six calves inoculated with a mixture of two laboratory cytopathic reference strains of bovine viral diarrhea virus (bvdv)-oregon c24 v and nadl. the clinical picture was accompanied by biphasic body temperature elevation, transient leukopenia and a decrease in the number of lymphocytes. high dose of viruses and multiple routes of inoculation promoted the development of clinical and hematolo ... | 2000 | 10855660 |
| germinal centre localization of bovine viral diarrhoea virus in persistently infected animals. | immunohistochemical analysis of peripheral lymph nodes from gnotobiotic calves persistently infected with bovine viral diarrhoea virus (bvdv) revealed extensive deposition of e(rns) and localization of the viral genome in the light zone of germinal centres. viral antigen co-localized with immunoglobulin in the germinal centres and was shown to be extracellular. despite the presence of viral antigen in germinal centres, circulating anti-bvdv antibody was not detected. these findings provide evide ... | 2000 | 10859371 |
| generation and characterization of a hepatitis c virus ns3 protease-dependent bovine viral diarrhea virus. | unique to pestiviruses, the n-terminal protein encoded by the bovine viral diarrhea virus (bvdv) genome is a cysteine protease (npro) responsible for a self-cleavage that releases the n terminus of the core protein (c). this unique protease is dispensable for viral replication, and its coding region can be replaced by a ubiquitin gene directly fused in frame to the core. to develop an antiviral assay that allows the assessment of anti-hepatitis c virus (hcv) ns3 protease inhibitors, a chimeric b ... | 2000 | 10864644 |
| mechanism of action of a pestivirus antiviral compound. | we report here the discovery of a small molecule inhibitor of pestivirus replication. the compound, designated vp32947, inhibits the replication of bovine viral diarrhea virus (bvdv) in cell culture at a 50% inhibitory concentration of approximately 20 nm. vp32947 inhibits both cytopathic and noncytopathic pestiviruses, including isolates of bvdv-1, bvdv-2, border disease virus, and classical swine fever virus. however, the compound shows no activity against viruses from unrelated virus groups. ... | 2000 | 10869440 |
| virological and serological studies on the role of pi-3 virus, brsv, bvdv and bhv-1 on respiratory infections of cattle. i. the detection of etiological agents by direct immunofluorescence technique. | nasal cells extracted from nasal swabs obtained from 95 cattle with signs of respiratory disease, out of eleven different herds, were tested for bhv-1, pi-3 virus, brsv and bvdv using direct immunofluorescence technique. viral antigen positive samples were detected in seven out of eleven herds examined. of the 95 individual diseased cattle, 19 were found positive for at least one viral antigen. it was found that especially bhv-1 and pi-3 virus are important causative agents in cattle respiratory ... | 2000 | 10887671 |
| ns3 serine protease of bovine viral diarrhea virus: characterization of active site residues, ns4a cofactor domain, and protease-cofactor interactions. | the gene expression of bovine viral diarrhea virus (bvdv), a pestivirus, occurs via translation of a hypothetical polyprotein that is processed cotranslationally and posttranslationally by viral and cellular enzymes. a protease located in the n-terminal region of nonstructural (ns) protein ns3 catalyzes the cleavages, leading to the release of ns4a, ns4b, ns5a, and ns5b. our study provides experimental evidence that histidine at position 1658 and aspartic acid at position 1686 constitute togethe ... | 2000 | 10915606 |
| lack of virus transmission from bovine viral diarrhoea virus infected calves to susceptible peers. | none of 14 calves not previously exposed to bvdv became infected after being forced to have nose-to-nose contact with a group of 5 calves primarily infected with bvdv. these were 5 male calves primarily infected with a type i bvdv strain, after nose-to-nose contact with a persistently viraemic calf. all 5 became infected and were clinically affected. they were slightly depressed and pyretic at 8-9 days post-infection, with a body temperature of up to 41.6 degrees c, but no medical treatment was ... | 2000 | 10920480 |
| an actin-binding protein is involved in pestivirus entry into bovine cells. | infection of bovine cells with bovine viral diarrhoea virus (bvdv) can be blocked by the monoclonal antibody (mab) bvd/ca 26, which is directed against a cellular membrane protein. to characterize this molecule, it was isolated and purified by column chromatography. it was found to be an acidic, glycosylated membrane protein consisting of two polypeptide chains of about 28 and 56 kda. under non-reducing conditions the chains formed multimers of about 200 kda. in an actin binding assay the 56 kda ... | 2000 | 10930657 |
| bovine viral diarrhea virus types 1 and 2 antibody response in calves receiving modified live virus or inactivated vaccines. | serums from calves receiving eight different commercial vaccines containing modified live virus (mlv) or inactivated bovine viral diarrhea virus (bvdv) immunogens were assayed for antibodies to types 1 and 2 bvdv strains. the immune response to the types 1 and 2 bvdv strains were evaluated in 48 calves receiving one of the eight vaccines for each group. for 7/8 vaccines, the bvdv vaccine immunogen was only type 1 whereas the remaining vaccine contained both types 1 and 2 immunogens. calves admin ... | 2000 | 10930681 |
| mutations in the 5' nontranslated region of bovine viral diarrhea virus result in altered growth characteristics. | the 5' nontranslated region (ntr) of pestiviruses functions as an internal ribosome entry site (ires) that mediates cap-independent translation of the viral polyprotein and probably contains additional cis-acting rna signals involved in crucial processes of the viral life cycle. computer modeling suggests that the 5'-terminal 75 nucleotides preceding the ires element form two stable hairpins, ia and ib. spontaneous and engineered mutations located in the genomic region comprising ia and ib were ... | 2000 | 10933696 |
| bovine viral diarrhea viral infections in feeder calves with respiratory disease: interactions with pasteurella spp., parainfluenza-3 virus, and bovine respiratory syncytial virus. | the prevalence of bovine viral diarrhea virus (bvdv) infections was determined in a group of stocker calves suffering from acute respiratory disease. the calves were assembled after purchase from tennessee auctions and transported to western texas. of the 120 calves, 105 (87.5%) were treated for respiratory disease. sixteen calves died during the study (13.3%). the calves received a modified live virus bhv-1 vaccine on day 0 of the study. during the study, approximately 5 wk in duration, sera fr ... | 2000 | 10935880 |
| bluetongue and persistent bovine viral diarrhea virus infection causing generalized edema in an adult bull. | 2000 | 10935900 | |
| co-administration of il-2 enhances antigen-specific immune responses following vaccination with dna encoding the glycoprotein e2 of bovine viral diarrhoea virus. | induction of effective immunity requires the delivery of a protective antigen with appropriate co-stimulatory signals. for bovine viral diarrhoea virus (bvdv) this antigen is the major viral glycoprotein e2. neutralising antibodies are directed towards the e2 protein and passive transfer of antibodies in serum or colostrum can completely protect against viral infection. dna vaccination of mice with a construct encoding the e2 glycoprotein induced neutralising antibody levels that were potentiall ... | 2000 | 10946143 |
| detection and characterization of genetic recombination in cytopathic type 2 bovine viral diarrhea viruses. | in cytopathic bovine viral diarrhea virus genotype 1 (bvdv1) isolates, insertions are reported at position a (amino acid [aa] 1535) and position b (aa 1589). insertions at position b predominate. in this survey it was found that in bvdv2, insertions at position a predominate. possible reasons for this difference in relative frequency are discussed. | 2000 | 10954582 |
| inactivation and clearance of viruses during the manufacture of high purity factor ix. | haemophilia is a bleeding disorder characterised by a deficiency in factor ix. replacement therapy in the form of a factor ix concentrate is a widely accepted practice. in this paper we describe a double virus inactivated chromatographic process for producing a high purity factor ix product, monofix((r))-vf. the process involves separation of the prothrombin complex by cryoprecipitation, fraction i precipitation and deae-cellulose adsorption, further ion-exchange chromatography of crude factor i ... | 2000 | 10964439 |
| exploiting polymerase promiscuity: a simple colorimetric rna polymerase assay. | we developed a convenient colorimetric assay for monitoring rna synthesis from dna-dependent rna polymerases (ddrp) and viral rna-dependent rna polymerases (rdrp). atp and gtp with a p-nitrophenyl moiety attached to the gamma-phosphate were synthesized (pnp-ntps). these pnp-ntps can be used for rna synthesis by several rna polymerases, including the rdrps from brome mosaic virus and bovine viral diarrhea virus and the ddrps from bacteriophage t7 and sp6. when the polymerase reactions were perfor ... | 2000 | 10964785 |
| presence of bovine viral diarrhea virus (bvdv) e2 glycoprotein in vsv recombinant particles and induction of neutralizing bvdv antibodies in mice. | we generated a recombinant vesicular stomatitis virus (vsv-e2) encoding the bovine viral diarrhea virus (bvdv) e2 glycoprotein with the vsv-g protein signal peptide. infection of bhk21 cells with vsv-e2 induced the synthesis of a recombinant e2 (re2) that comigrated with authentic bvdv-e2 in page-sds gels. non-reducing immunoblots showed that re2 is a disulfide bond-linked homodimer with at least 10-fold higher avidity for conformation-dependent anti-bvdv-e2 antibodies than its reduced monomeric ... | 2000 | 10989181 |
| e2-p7 region of the bovine viral diarrhea virus polyprotein: processing and functional studies. | the genes encoding pestivirus e2 and ns2-3 are separated by a sequence that encodes a small hydrophobic polypeptide with an apparent molecular mass of 6 to 7 kda (p7). it has been shown that cleavage between e2 and p7 is incomplete, resulting in proteins e2-p7, e2, and p7. we found no precursor-product relationship between e2-p7 and e2, which indicates a stable nature of e2-p7. to study the function of the e2-p7 region of the polyprotein, mutations were introduced into an infectious cdna of bovi ... | 2000 | 11000219 |
| bovine viral diarrhea virus induced apoptosis correlates with increased intracellular viral rna accumulation. | non-cytopathic (ncp) and cytopathic (cp) parent-daughter pairs are often isolated from cattle with bovine viral diarrhea virus (bvdv) induced mucosal disease. alignment of these pair genomes revealed that genetic changes in cp bvdv involve the ns2-3 coding region and correlate with expression of ns3. however, additional mutations are present elsewhere in the genomes of these natural pairs, precluding unambiguous mapping of this function to the ns2-3 region. to evaluate this phenomenon in identic ... | 2000 | 11018279 |
| comparison of virus isolation and reverse transcription polymerase chain reaction assay for detection of bovine viral diarrhea virus in bulk milk tank samples. | the use of a reverse transcriptase polymerase chain reaction (rt-pcr) assay to screen bulk milk tank samples for bovine viral diarrhea virus (bvdv) has proven to be a sensitive and economical means to evaluate the lactating animals in a herd. the assay is capable of detecting the presence of a single persistently infected animal within a group of several hundred cows. over a 3-year period, 144 samples from 97 farms were tested for bvdv using an rt-pcr assay in conjunction with a classical virus ... | 2000 | 10730955 |
| interferon-gamma and interleukin-4 mrna expression by peripheral blood mononuclear cells from pregnant and non-pregnant cattle seropositive for bovine viral diarrhea virus. | the acceptance of the fetal allograft by pregnant women and mice seems to be associated with a shift from a th 1 dominated to a th 2 dominated immune response to certain infectious agents. the goal of this study was to examine cytokine expression in peripheral blood mononuclear cells (pbmcs) from cattle immune to bovine viral diarrhea virus (bvdv) to determine whether pregnancy also has an influence on the type of immune response in this species. forty-six heifers and cows between 14 months and ... | 2000 | 11137119 |
| giraffe strain of pestivirus: its taxonomic status based on the 5'-untranslated region. | the 5'-untranslated region (5'-utr) of the 'giraffe' strain of pestivirus was sequenced for comparison with those of other pestiviruses from cattle, sheep, goats, and swine. a phylogenetic tree constructed with these strains suggested that the 'giraffe' strain was allocated to a new taxon. this observation was also confirmed by a newly proposed method based on palindromic nucleotide substitutions (pns) at the three variable regions in the 5'-utr. other reported pestivirus strains isolated from d ... | 2000 | 11145272 |
| [detection of the genome of bovine viral diarrhea virus (bvdv) using the polymerase chain reaction after reverse transcription (rt-pcr): comparison of methods for the isolation of ribonucleic acid (rna) from clinical samples]. | the rt-pcr is an in vitro technique that is increasingly being used for diagnosis of viral animal pathogens. due to its high sensitivity it is considered as an alternative to current standard methods for detecting bvdv especially in pooled samples, e.g. from bulk tank milk. a prerequisite for the performance of rt-pcr is an efficient and simple method for sample preparation. the aim of this work was to compare the efficiency of three commercially available kits for rna extraction, and their suit ... | 2000 | 11153228 |
| evaluation of a new sandwich elisa kit that uses serum for detection of cattle persistently infected with bvd virus. | cattle immunotolerant to and persistently infected (pi) with bovine viral diarrhea (bvd) virus (bvdv) constitute the mechanism by which bvdv persists in and spreads among cattle herds. detection and elimination of pi cattle are necessary for control of bvd. serum is an excellent specimen for bvd pi testing because of high survivability of bvdv in serum and ease of collection, storage, and handling. currently, microtiter virus isolation (vi) employing serum and sandwich elisas (s-elisa) on tissue ... | 2000 | 11193646 |
| virus neutralizing antibodies against a panel of 18 bvdv isolates in calves vaccinated with rispoval rs-bvd. | seven of nine colostrum-deprived calves, free from infection with bovine virus diarrhoea virus (bvdv), were vaccinated with rispoval rs-bvd on two occasions, 21 days apart, while the other two were kept as bvdv infection controls. the virus neutralizing (vn) serum antibodies induced by vaccination were tested for their ability to neutralize 18 european bvdv isolates, including laboratory reference strains and recent field isolates, both cytopathic and non-cytopathic biotypes as well as genotypes ... | 2000 | 11204126 |
| quality controls for bovine viral diarrhea virus-free ivf embryos. | introduction of bovine viral diarrhea virus (bvdv) with cumulus-oocyte-complexes (cocs) from the abattoir is a concern in the production of bovine embryos in vitro. further, international embryo transfer society (iets) guidelines for washing and trypsin treatment of in-vivo-derived bovine embryos ensure freedom from a variety of pathogens, but these procedures appear to be less effective when applied to ivf embryos. in this study, cocs were exposed to virus prior to ivm, ivf and ivc. then, virus ... | 2000 | 10735047 |
| response to modified live and killed multivalent viral vaccine in regularly vaccinated, fresh dairy cows. | vaccination programs for viral pathogens in the dairy industry span the full spectrum of possibilities even though few of these have been evaluated in field situations. one such program is the vaccination of fresh cows 30 to 60 days postpartum with modified live viral (mlv) vaccines. the purpose of this study was to evaluate the antibody response to booster vaccinations during this period. the impact of vaccinations on milk production and reproductive performance was also examined. the response ... | 2000 | 19757565 |
| experimental fetal challenge using type ii bovine viral diarrhea virus in cattle vaccinated with modified-live virus vaccine. | nineteen open heifers or cows were vaccinated 45 days prior to breeding with a modified-live bovine viral diarrhea virus (bvdv) vaccine. an additional six animals were not vaccinated and served as controls. all 25 animals were estrus-synchronized and bred. at 75 days of gestation, the 25 pregnant animals were experimentally infected with a type ii isolate of bvdv by intranasal inoculation. at 75 days after inoculation, the animals were euthanized and each fetus was removed and retained for sampl ... | 2001 | 19746658 |
| informative value of an indirect enzyme-linked immunosorbent assay (elisa) for the detection of bovine viral diarrhoea virus (bvdv) antibodies in milk. | bulk and individual milk samples from 117 herds located in brittany (west france) were used to assess: (i) the performance characteristics of an indirect enzyme-linked immunosorbent assay (elisa) applied to individual milk for the detection of antibodies to bovine viral diarrhoea virus (bvdv); and (ii) the relationship between the bulk milk result obtained from this test and the within-herd prevalence of antibody-positive lactating cows. this elisa test was based on a monoclonal antibody directe ... | 2001 | 11765806 |
| platelet aggregation responses and virus isolation from platelets in calves experimentally infected with type i or type ii bovine viral diarrhea virus. | altered platelet function has been reported in calves experimentally infected with type ii bovine viral diarrhea virus (bvdv). the purpose of the present study was to further evaluate the ability of bvdv isolates to alter platelet function and to examine for the presence of a virus-platelet interaction during bvdv infection. colostrum-deprived holstein calves were obtained immediately after birth, housed in isolation, and assigned to 1 of 4 groups (1 control and 3 treatment groups). control calv ... | 2001 | 11768131 |
| a family of closely related bovine viral diarrhea virus recombinants identified in an animal suffering from mucosal disease: new insights into the development of a lethal disease in cattle. | induction of lethal mucosal disease (md) in cattle is linked to the generation of cytopathogenic (cp) bovine viral diarrhea virus (bvdv) in animals persistently infected with a noncytopathogenic bvdv. in most cases the cp variants are generated by recombination with cellular or viral sequences. bvdv was obtained from the serum of an md animal and propagated in tissue culture without plaque purification. analysis of cdna clones established from rna of these cells showed that apparently a variety ... | 2001 | 11878878 |
| genetic typing of ruminant pestivirus strains from northern ireland and the republic of ireland. | a study was performed to investigate the genotypes and sub-groups of pestiviruses present in ruminants in ireland. these comprised one ovine and eighteen bovine pestiviruses from northern ireland and six bovine pestiviruses from the republic of ireland. a 288 base pair (bp) portion of the 5'-non coding region (5'-ncr) from each of 25 pestiviruses collected over a period of 31 years was amplified by reverse-transcription-polymerase chain reaction (rt-pcr) and the product directly sequenced. from ... | 2001 | 11883891 |