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protection of pregnant cattle and their fetuses against infection with bovine viral diarrhea virus type 1 by use of a modified-live virus vaccine.to determine efficacy of a vaccine containing modified-live bovine viral diarrhea virus (bvdv) type 1 for protecting pregnant cows and their fetuses against virulent heterologous bvdv type 1.19989829398
effect of concurrent experimentally induced bovine respiratory syncytial virus and bovine viral diarrhea virus infection on respiratory tract and enteric diseases in calves.to compare experimentally induced concurrent bovine viral diarrhea virus (bvdv) and bovine respiratory syncytial virus (brsv) infection with single virus infection.19989829401
insertion of a bovine smt3b gene in ns4b and duplication of ns3 in a bovine viral diarrhea virus genome correlate with the cytopathogenicity of the virus.bovine viral diarrhea virus (bvdv) infection in cattle can lead to the development of a fatal syndrome called mucosal disease (md). the induction of md requires co-existence of two biotypes of bvdv: cytopathic (cp) and non-cytopathic (ncp). studies have shown that in some cases, cp viruses are generated from ncp viruses by cellular gene insertions, duplications or rearrangements in the viral genome. cellular ubiquitin gene is the most frequently reported insert in bvdv 1. here we report the find ...19989833880
genetic analysis of the internal ribosome entry segment of bovine viral diarrhea virus.pestiviruses and hepaciviruses are atypical members of the flaviviridae due to their unique biological properties, including the utilization of internal ribosome entry for translation initiation. in contrast to internal initiation in picornaviruses, which depends on numerous canonical initiation factors, the mode of internal ribosome entry in pestiviruses and hepaciviruses resembles prokaryotic translation initiation. to identify functionally important elements within the bovine viral diarrhea v ...19989837801
validation of the heat treatment step used in the production of diaspirin crosslinked hemoglobin (dclhb) for viral inactivation.a series of experiments was performed to assess the ability of the heat treatment step used in the manufacture of diaspirin crosslinked hemoglobin (dclhb) to inactivate viruses. in-process solutions (reaction mixtures after the crosslinking process) from six different manufacturing lots were used as test media in a 1:680 scaled down system in which the key process parameters used in the large scale production were duplicated. the inactivation of five different viruses (bovine viral diarrhea viru ...19989844723
use of polymerase chain reaction to simultaneously detect and type bovine viral diarrhoea viruses isolated from clinical specimens.the techniques of indirect immunofluorescence (if), immuno-peroxidase (ip) staining and the one-step reverse transcriptase polymerase chain reaction (rt-pcr) were compared for detection of 102 isolates of bovine viral diarrhoea virus (bvdv) in infected cell cultures. the bvdv was obtained from bovine clinical specimens, including sera, buffy coats and tissues, submitted from farms located in the states of iowa and wisconsin, united states of america. the if technique detected 88/102 (86.3%) of t ...19989850544
detection of antibodies to bovine viral diarrhoea virus (bvdv) and characterization of genomes of bvdv from brazil.an elisa for the detection of antibodies to bovine viral diarrhea virus (bvdv) was developed based on antigens derived from a genotype i bvdv strain isolated in switzerland. using monoclonal antibodies we showed that this antigen contained the conserved non-structural protein ns3 whereas it essentially lacked the more strain-specific e2 surface glycoprotein. this elisa has a sensitivity of 97.5% and a specificity of 99.2% as compared to the serum neutralization test (snt). preliminary experiment ...19989850989
a stable cell line with a proportion of cells persistently infected with bovine viral diarrhoea virus.bovine turbinate (btu) and lamb testis (lt) cell lines persistently infected with bovine viral diarrhoea virus (bvdv) arose as a result of a single change of medium containing commercial foetal calf serum. infected cells comprise 30% and 50% respectively, of the total cell population, determined by immunohistochemical staining. the ratio of positive cells has remained unchanged during successive passages. characterization of the persistently-infected btu cells (btui) showed that only full length ...19989850992
monoclonal antibodies to the e2 protein of a new genotype (type 2) of bovine viral diarrhea virus define three antigenic domains involved in neutralization.bovine viral diarrhea virus (bvdv) has recently been segregated into two genotypes, namely, bvdv 1 and bvdv 2. viruses of the bvdv 2 genotype are a cause of hemorrhagic and acute fatal disease in cattle in the us and canada. in this study, monoclonal antibodies (mabs) to the newly described bvdv 2 were produced after immunization with virus or a combination of virus and e2 peptide. from an original panel of 17 mabs, 13 mabs were identified as e2-specific by reactivity with a bvdv 2 recombinant e ...19989870585
prolonged nasal shedding and viraemia of cytopathogenic bovine virus diarrhoea virus in experimental late-onset mucosal disease.a calf persistently infected with bovine virus diarrhoea virus (bvdv) was super-infected with a heterologous bvdv strain, c874, which contained non-cytopathogenic and cytopathogenic viruses. high titres of cytopathogenic bvdv were recovered in the three to four weeks after the challenge. thereafter low titres of cytopathogenic virus were recovered repeatedly from the blood and the nose, with the titres in nasal secretions increasing in the four weeks before the onset of clinical signs. neutralis ...19989871955
new methods for inactivation of lipid-enveloped and non-enveloped viruses.two new methods are described for inactivating lipid-enveloped and non-enveloped viruses in plasma-derived products such as coagulation factors and intravenous immunoglobulin (igiv). iodine/sephadex delivers iodine to igiv solutions in a slow, controlled way and allows for inactivation of > or = 4 logs of porcine parvovirus (ppv), a hardy non-enveloped virus, under conditions which do not measurably damage the structural or functional properties of the igiv, and with essentially no iodination of ...19989873761
distribution of bovine virus diarrhoea virus in tissues and white blood cells of cattle during acute infection.this study is performed to gain knowledge about the quantitative distribution of bovine virus diarrhoea virus (bvdv) in tissues and white blood cells (wbc) at different intervals after acute infection. ten specific pathogen-free calves were intranasally inoculated with 10(5) 50% tissue culture infective dose of the non-cytopathic bvdv strain 4800. twelve hours after inoculation tonsil biopsies were taken and wbc were collected daily for virus isolation and titration. each day one calf was killed ...19989874100
anti-viral effect of interferon-alpha on bovine viral diarrhea virus.to get basic information to control persistent virus infection among domestic animals by cytokines, the antiviral activity of four natural human cytokines against bovine viral diarrhea virus (bvdv) was evaluated. normal bovine peripheral blood mononuclear leukocytes (pbml) and fetal bovine muscular cells (fbmc) were treated with varying doses of human interferon (ifn)-alpha, ifn-gamma, tumor necrosis factor (tnf)-alpha and tnf-beta. the antiviral activity in treated cells was measured by the tit ...19989879534
characterization of an autonomous subgenomic pestivirus rna replicon.as an initial approach to define the requirements for the replication of bovine viral diarrhea virus (bvdv), a member of the flaviviridae family with a positive-strand rna genome, full-length genomic and subgenomic rnas were originated by in vitro transcription of diverse bvdv cdna constructs and transfected into eucaryotic host cells. rna replication was measured either directly by an rnase protection method or by monitoring the synthesis of viral protein. when full-length bvdv crna was initial ...19989499097
[cytopathogenic bovine viral diarrhea viruses induce apoptosis in bovine cell cultures].the pestivirus bovine viral diarrhea (bvd) virus is the causative agent of mucosal disease (md) of cattle. from persistently infected animals, only the non-cytopathogenic biotype bvd virus can be isolated. cattle succumbing to md additionally harbour cytopathogenic bvd virus. while cp bvd virus isolates induce a cytopathic effect (cpe) in susceptible monolayer cell cultures, infection with ncp bvd virus isolates has no visible effect. the purpose of this study was to investigate the correlation ...19989499630
evaluation of bovine viral diarrhea virus control using a mathematical model of infection dynamics.a mathematical model for infection with bovine viral diarrhea virus (bvdv) was created comprising a series of coupled differential equations. the model architecture is a development of the traditional model framework using susceptible, infectious and removed animals (the sir model). the model predicts 1.2% persistent infection (within the range of field estimates) and is fairly insensitive to alterations of structure or parameter values. this model allows us to draw important conclusions regardi ...19989500167
detection of bvdv in bovine embryos derived from persistently infected heifers by pcr. 19989501387
the effect of different bovine viral diarrhea virus genotypes and biotypes on the metabolic activity and activation status of bovine peripheral blood mononuclear cells.the effects of cytopathic (cp) and non-cytopathic (ncp) bovine viral diarrhea virus (bvdv) on the cellular metabolic activity and activation status of bovine peripheral blood mononuclear cells (pbmc) were investigated. cellular dna and protein synthesis was determined by [3h]thymidine and [3h]valine incorporation, respectively, in phytohemagglutinin (pha)-stimulated pbmc. all cp strains and most ncp bvdv strains significantly inhibited dna synthesis in pha-stimulated pbmc; however, only cp bvdv ...199810189190
characterization of a bovine viral diarrhea virus isolated from roe deer in germany.the 5' untranslated region (5' utr) of cytopathogenic pestiviruses isolated from two seronegative roe deer (capreolus capreolus) in northern germany was partially sequenced and compared with those of 28 other pestiviruses. due to the occurrence within a narrow location and the complete identity of the sequenced fragments from both roe deer isolates (sh9 and sh11) they seem to belong to the same bovine virus diarrhea virus (bvdv) strain called sh9/11. this strain is highly homologous (up to 93% i ...19989476225
serologic evidence of bovine viral diarrhea virus in free-ranging rabbits from germany.from 1993 to 1995, 100 blood samples and 97 spleen samples of free-ranging rabbits (oryctolagus cuniculus) from northern germany were tested for prevalence of different bovine viral diarrhea virus (bvdv) antibodies and bvdv antigen, respectively. forty sera (40%) were positive for antibodies to one or more of three cytopathogenic bvdv strains (nadl, grub 313/83, and roe deer isolate sh9/11). microneutralization test (nt) titers ranged from 5 to 13. moreover, 13 of 35 nt positive sera also were p ...19989476243
phylogenetic evidence for the improved rna higher-order structure in internal ribosome entry sequences of hcv and pestiviruses.the strong requirement for a small segment of the 5'-proximal coding sequence of hepatitis c virus (hcv) is one of the most remarkable features in the internal initiation of hcv mrna translation. phylogenetic analysis and rna folding indicate a common rna structure of the 5' untranslated region (utr) of hcv and the animal pestiviruses, including hcv types 1-11, bovine viral diarrhea (bvdv), border disease virus (bdv) and hog cholera (hocv). although the common rna structure shares similar featur ...19989926403
virus validation of ph 4-treated human immunoglobulin products produced by the cohn fractionation process.to assess the virus reducing capacity of cohn's cold ethanol fractionation process for the production of intravenous (ivig) and intramuscular (imig) immunoglobulin products, and treatment of these products at ph 4, a validation study of virus removal and/or inactivation was performed using both lipid-enveloped viruses [human immunodeficiency virus (hiv), bovine viral diarrhoea virus (bvdv) and pseudorabies virus (psr)], and non-lipid-enveloped viruses [(simian virus 40 (sv40) and encephalomyocar ...199810403030
removal of viruses from human intravenous immune globulin by 35 nm nanofiltration.viral safety is an important prerequisite for clinical immunoglobulin preparations. a common manufacturing practice is to utilize several virus removal/inactivation process steps to ensure the safety of human intravenous immunoglobulin (ivig). in this regard, we examined the use of planova 35 nm filters to reduce potential loads of both non-enveloped and enveloped viruses prior to end-stage solvent detergent treatment. the nanofiltration process was validated for removal of a variety of envelope ...199810403036
inactivation kinetics of model and relevant blood-borne viruses by treatment with sodium hydroxide and heat.to determine the efficacy of a clean-in-place system for the inactivation of viruses present in human plasma, the effect of 0.1 m sodium hydroxide at 60 degrees c on viral infectivity was investigated. inactivation of the following model and relevant viruses were followed as a function of time: human hepatitis a virus (hav), canine parvovirus (cpv; a model for human parvovirus b-19) pseudorabies virus (prv, a model for hepatitis b virus), and bovine viral diarrhoea virus (bvdv, a model for hepat ...199810208725
antigenic characterization of brazilian bovine viral diarrhea virus isolates by monoclonal antibodies and cross-neutralization.nineteen brazilian isolates of bovine viral diarrhea virus (bvdv) were characterized antigenically with a panel of 19 monoclonal antibodies (mabs) (corapi wv, donis ro and dubovi ej (1990) american journal of veterinary research, 55: 1388-1394). eight isolates were further characterized by cross-neutralization using sheep monospecific antisera. analysis of mab binding to viral antigens by indirect immunofluorescence revealed distinct patterns of reactivity among the native viruses. local isolate ...19989921280
changes in ovarian follicles following acute infection with bovine viral diarrhea virus.bovine viral diarrhea virus (bvdv) has been associated with several reproductive problems in cattle, including poor fertility, early embryonic deaths, abortion and congenital anomalies. little is known about the cause of poor fertility in cows acutely infected with bvdv. the purpose of this study was to identify changes in ovarian function following acute infection with noncytopathic bvdv. the ovaries of 5 bvdv sero-negative and virus-negative pubertal heifers were monitored daily for 4 consecut ...199810732038
association of bovine embryos produced by in vitro fertilization with a noncytopathic strain of bovine viral diarrhea virus type ii.in the first experiment, heifers were infected experimentally with bovine viral diarrhea virus type ii (bvdv-type ii, strain cd87; characterized by high morbidity and mortality). subsequently, in vitro fertilized embryos were produced from oocytes collected on day 4, 8, and 16 post infection. in a total of 29 heifers, the infectious virus was detected in 55% of the samples of the follicular fluid, in 10% of the oviductal cells, in 10% of the uterine flushes and in 41% of the in vitro fertilized ...199810732060
washing and trypsin treatment of in vitro derived bovine embryos exposed to bovine viral diarrhea virus.gametes, somatic cells and materials of animal origin in media are potential sources for introducing bovine viral diarrhea virus (bvdv) into systems for production of ivf bovine embryos. further, the efficacy of washing and trypsin treatment for removal of bvdv from ivf embryos is questionable. washing and trypsin treatments recommended by the international embryo transfer society for in vivo-derived embryos were applied to in vitro-derived, virus-exposed, bovine embryos in this side-by-side com ...199810734446
noncytopathogenic bovine viral diarrhea virus (bvdv) reduces cleavage but increases blastocyst yield of in vitro produced embryos.the growing application of in vitro embryo production systems that utilize slaughterhouse tissues of animals of unknown health status conveys the risk of disease transmission. one pathogen of concern in this regard is bovine viral diarrhea virus (bvdv), and the objective of this study was to investigate the effect of bvdv on in vitro embryonic development. a bovine in vitro embryo production system was experimentally infected with bvdv at 2 stages: prior to in vitro maturation by incubating cumu ...199810734451
the associations of viral and mycoplasmal antibody titers with respiratory disease and weight gain in feedlot calves.blood samples from 32 groups of calves (n = 700) were taken on arrival and after 28-35 days at the feedlot. eleven groups were housed in feedlots in ontario, and 21 groups in feedlots in alberta. serum antibody titers to bovine viral diarrhea virus (bvdv), bovine respiratory syncytial virus (brsv), parainfluenza virus type 3 (piv-3), infectious bovine rhinotracheitis virus (ibrv), mycoplasma dispar and m. bovis, plus data on bovine corona virus (bcv) from a previous study were investigated for t ...199912001336
risk factors for neospora caninum-associated abortion storms in dairy herds in the netherlands (1995 to 1997).a 2 to 1 matched case control study design was used to analyze herd level risk factors for neospora caninum-associated abortion storms in 47 dairy herds. data were obtained using a questionnaire regarding the state of affairs at the farms over the 2 years prior to the abortion storm. the questionnaire included 120 variables considered to be potential risk factors for either introduction of infection or recrudescence of chronic infection. the relationship between risk factors and case control pai ...199910734392
sensitivity comparison for detection of respiratory bovine coronaviruses in nasal samples from feedlot cattle by elisa and isolation with the g clone of hrt-18 cells.a monoclonal antibody-based capture enzyme-linked immunosorbent assay (elisa) was developed to detect respiratory bovine coronavirus (rbcv) antigens in nasal swabs collected from cattle showing signs of respiratory tract disease following shipping. these samples had been previously tested for rbcv by inoculation of g clone cultures of human rectal tumor cells (hrt-18g) and for bovine herpes virus 1, parainfluenza virus 3, bovine adenovirus, bovine respiratory syncytial virus, and bovine viral di ...19999925206
obtaining immunologically active bovine viral diarrhea virus (bvdv) proteins for enzyme linked immunosorbent assay (elisa).we report here the preparation of bvdv antigen (ag) to obtain adequate quantities of pure active viral proteins from madin darby bovine kidney (mdbk) cell culture infected with bvdv cytophatic oregon c24v strain. sds-page, immunodot, ecl-western blot and elisa showed the best specificity and activity of bvdv ag obtained from infected cells only by mild experimental conditions. bvdv ag preparations showed the peculiar bvdv sensitivity to proteases, nonionic surfactants and tend for protein degrad ...199910726311
prevalence of antibodies to ibr and bvd viruses in dairy cows with reproductive disorders.we determined the prevalence of antibodies to infectious bovine rhinotracheitis virus (ibrv) and bovine viral diarrhea virus (bvdv) in sera of dairy cows on 4 different farms in the republic of croatia. a high percentage (60.8%) of cows had various reproductive disorders. the results showed that seroprevalence of infectious bovine rhinotracheitis (ibr) was 85.8% and that of bovine viral diarrhea (bvd) was 79.2% in tested cows. antibodies to both viruses were found in 80.8% of cows with reproduct ...199910729010
bovine viral diarrhea virus: its effects on estradiol, progesterone and prostaglandin secretion in the cow.bovine viral diarrhea virus (bvdv) is a major cattle pathogen responsible for a spectrum of symptoms, including reproductive failure. this study was designed to establish the effects of bvdv infection on estradiol, progesterone and pgf2alpha secretion in the cow. seven bvdv-free cows were challenged with non-cytopathogenic bvdv (strain pe 515: 5x10(6) tissue culture infected dose50) so that peak viremia occurred during the initial phase of luteal development in a synchronized estrous cycle. ovul ...199910729080
quantity and infectivity of embryo-associated bovine viral diarrhea virus and antiviral influence of a blastocyst impede in vitro infection of uterine tubal cells.in previous studies, bovine viral diarrhea virus (bvdv) remained associated with ivf embryos after viral exposure and washing. however, uterine tubal cells (utc) were not infected when exposed embryos were washed and individually co-cultured with them. the objective of this study was to evaluate quantity and infectivity of embryo-associated virus and antiviral influence of a blastocyst as possible explanations for failure to infect the utc in vitro. morulae and blastocysts were produced in vitro ...199910735128
a hierarchical trend model for bovine virus diarrhoea virus (bvdv) sero-conversion in norwegian dairy herds from 1993 through 1997.the norwegian bovine virus diarrhoea (bvd) control-and-eradication program performed annual testing of the national cattle population since its first screening in january 1993. a bulk-tank milk elisa antibody test was used for the initial screening of dairy herds. based on the annual bulk-tank milk-test result, a binary variable denoting herd sero-conversion (a surrogate measure for incidence) was created. the count of herds with sero-conversion in each community was regressed on year and the in ...199911018733
experimental model of type ii bovine viral diarrhea virus-induced thrombocytopenia in neonatal calves.thrombocytopenia has been associated with type ii bovine viral diarrhea virus (bvdv) infection in immunocompetent cattle, but the mechanism is unknown. the purpose of the present study was to develop and characterize a model of type ii bvdv-induced thrombocytopenia. colostrum-deprived holstein calves were obtained immediately after birth, given a bvdv-negative and bvdv antibody-negative plasma transfusion, housed in an isolation facility, and randomly assigned to either control (n = 4) or infect ...199912968732
bovine viral diarrhea virus isolated from fetal calf serum enhances pathogenicity of attenuated transmissible gastroenteritis virus in neonatal pigs.a bovine viral diarrhea virus (bvdv-c) was isolated from swine tissue culture cells used to attenuate the transmissible gastroenteritis virus (tgev) after 68 passes. piglets given a pure culture of bvdv-c developed clinical signs similar to those of a mild tgev infection and recovered by 10 days postexposure. villous blunting and fusion was observed in the small intestine, and a lymphocyte depletion was observed in peyer's patches in the ileum. piglets given a combination of bvdv-c and attenuate ...199912968752
an experimental multivalent bovine virus diarrhea virus e2 subunit vaccine and two experimental conventionally inactivated vaccines induce partial fetal protection in sheep.the primary aim of a bovine virus diarrhea virus (bvdv) vaccine is to prevent transplacental transmission of virus. we studied the efficacy of two experimental conventionally inactivated vaccines, based on bvdv strain singer and containing a different antigen amount, against three antigenically different bvdv strains in a vaccination-challenge experiment in sheep. we also studied the efficacy of an experimental multivalent e2 subunit vaccine against four antigenically different bvdv strains. the ...199910217598
airborne transmission of bhv1, brsv, and bvdv among cattle is possible under experimental conditions.to control the diseases caused by bovine herpesvirus 1 (bhv1), bovine respiratory syncytial virus (brsv), and bovine virus diarrhoea virus (bvdv), it is crucial to know their modes of transmission. the purpose of this study was to determine whether these viruses can be transmitted by air to a substantial extent. calves were housed in two separate isolation stables in which a unidirectional airflow was maintained through a tube in the wall. in one stable, three of the five calves were experimenta ...199910227122
typing of bovine viral diarrhea viruses directly from blood of persistently infected cattle by multiplex pcr.a nested multiplex pcr was developed for genotyping of bovine viral diarrhea viruses (bvdvs). the assay could detect as little as 3 50% tissue culture infective doses of bvdv per ml and typed 42 out of 42 cell culture isolates. bvdv was also successfully typed, with or without rna extraction, from all 27 whole-blood samples examined from 22 carriers or probable carriers and 5 experimentally infected cattle.199910325368
the effect of high concentrations of cryoprotectants on the passage of bovine viral diarrhea virus through the zona pellucida of in vitro fertilized embryos.the effect of high concentrations of cryoprotectants on the passage of bovine viral diarrhea virus (bvdv) through the zona pellucida (zp) of intact bovine embryos during the pre-freezing step of cryopreservation was investigated in a series of experiments. in vitro fertilized (ivf) embryos at the blastocyst stage were exposed to 10(6) tcid50 bvdv (non-cytopathic ny-1 strain) in a 30% suspension of either ethylene glycol, glycerol, dmso, or 2 m sucrose in physiological saline for 10 min at 20 deg ...199910333065
serological survey of viral antibodies in llamas (lama glama) in argentina.this study analysed sera from 390 llamas (lama glama) from nine farms located in three different argentine provinces: buenos aires, cordoba and jujuy. the samples were tested for antibodies against 8 virus known to infect cattle: bovine herpesvirus type 1 (bhv-1), bovine viral diarrhea virus (bvdv), bovine adenovirus (badv iii), bovine enterovirus (bev), bovine rotavirus (brv), bluetongue virus (btv), bovine leukaemia virus (blv), and foot-and-mouth virus (fmdv) by conventional methods such as s ...199910337237
possible causes of diabetes mellitus in cattle infected with bovine viral diarrhoea virus.in cattle, we encountered insulin-dependent diabetes mellitus (iddm) associated with bovine viral diarrhoea virus (bvdv) infection. to estimate the correlation between iddm and bvdv infection, the distribution of bvdv in the pancreas and islet-cell antibody (ica) were investigated. the distribution of bvdv in the pancreas was examined by in situ hybridization using two oligonucleotide probes that recognized the gp25- and p14-coding regions of the bvdv gene. ica was examined by indirect fluoresce ...199910337243
use of bovine viral diarrhoea virus as an internal control for amplification of hepatitis c virus.screening for hepatitis c virus (hcv) by polymerase chain reaction (pcr) will be mandatory for screening blood and plasma donors in europe and elsewhere. this study describes an internally controlled, highly sensitive pcr method designed for screening blood donations in pools.199910341333
bovine herpes virus expressing envelope protein (e2) of bovine viral diarrhea virus as a vaccine candidate.the gene encoding the envelope protein (e2) of bovine viral diarrhea virus (bvdv) was expressed under the thymidine kinase (tk) promoter of korean bovine herpesvirus 1 (bhv-1) isolate. thymidine kinase negative (tk-) bhv-1 recombinants expressing e2 of bvdv were constructed and the expression of e2 was identified by immunofluorescence and western blotting. compared to wild type bhv-1, the recombinant bhv-1 had a delayed cytopathogenic effect in cells. the immunogenicity of the recombinant bhv-1 ...199910342291
experimental infection of calves with bovine viral diarrhea virus genotype ii (ny-93).to ascertain the virulence of bovine viral diarrhea virus (bvdv) genotype ii, isolate ny-93 was inoculated intranasally into 3 calves, 2 of which were treated with a synthetic glucocorticoid prior to and after virus inoculation. anorexia, fever (up to 42 c), dyspnea, and hemorrhagic diarrhea developed 6 days after intranasal inoculation with bvdv ny-93. the condition of all calves deteriorated further until the end of the study on day 14 postinoculation. the most significant postmortem macroscop ...199910353352
oxidative stress in cells infected with bovine viral diarrhoea virus: a crucial step in the induction of apoptosis.bovine viral diarrhoea virus (bvdv) belongs to the genus pestivirus of the family flaviviridae. both a noncytopathic (ncp) and an antigenically related cytopathic (cp) bvdv can be isolated from persistently infected animals suffering from mucosal disease. in every case studied so far, the genomic changes leading to the cp biotype correlate with the production of the ns3 nonstructural protein, which, in the ncp biotype, is present in its uncleaved form, ns23. this report shows that, in contrast t ...199910355761
localization of pestiviral envelope proteins e(rns) and e2 at the cell surface and on isolated particles.the glycoproteins e(rns) of classical swine fever virus (csfv) and e(rns) and e2 of bovine viral diarrhoea virus (bvdv) are shown to be located at the surface of infected cells by the use of indirect immunofluorescence and by cytofluorometric analysis. the positive immunostaining of the cell surface was further analysed by immunogold electron microscopy and it could be shown that only extracellular virions were labelled. gold granules were not seen at the cellular plasma membrane. in contrast to ...199910355762
nonhomologous rna recombination in bovine viral diarrhea virus: molecular characterization of a variety of subgenomic rnas isolated during an outbreak of fatal mucosal disease.four bovine viral diarrhea virus type 2 (bvdv-2) pairs consisting of cytopathogenic (cp) and noncp bvdv-2 were isolated during an outbreak of mucosal disease. comparative sequence analysis showed that the four noncp bvdv-2 isolates were almost identical. for the cp bvdv-2 isolates, viral subgenomic rnas were shown by northern blot to have a length of about 8 kb, which is about 4.3 kb shorter than the genome of noncp bvdv. cytopathogenicity and the expression of ns3 were both strictly correlated ...199910364314
bovine viral diarrhea virus quasispecies during persistent infection.analysis of viral genome sequences from two calves persistently infected with bovine viral diarrhea virus revealed a quasispecies distribution. the sequences encoding the glycoprotein e2 were variable, translating to a number of changes in predicted amino acid sequences. the ns3 region was found to be highly conserved in both animals. the number of e2 clones showing variant amino acids increased with the age of the animal and comparison of the consensus sequences at the different time points con ...199910364492
internal initiation of translation of bovine viral diarrhea virus rna.initiation of translation on the bovine viral diarrhea virus (bvdv) internal ribosomal entry site (ires) was reconstituted in vitro from purified translation components to the stage of 48s ribosomal initiation complex formation. ribosomal binding and positioning on this mrna to form a 48s complex did not require the initiation factors eif4a, eif4b, or eif4f, and translation of this mrna was resistant to inhibition by a trans-dominant eif4a mutant that inhibited cap-mediated initiation of transla ...199910366562
comparison of type i and type ii bovine viral diarrhea virus infection in swine.some isolates of type ii bovine viral diarrhea virus (bvdv) are capable of causing severe clinical disease in cattle. bovine viral diarrhea virus infection has been reported in pigs, but the ability of these more virulent isolates of type ii bvdv to induce severe clinical disease in pigs is unknown. it was our objective to compare clinical, virologic, and pathologic findings between type i and type ii bvdv infection in pigs. noninfected control and bvdv-infected 2-month-old pigs were used. a non ...199910369569
incidence of diarrhea among calves after strict closure and eradication of bovine viral diarrhea virus infection in a dairy herd.to determine whether strict closure of a dairy herd and eradication of bovine viral diarrhea virus (bvdv) infection would decrease incidence of diarrhea in calves during the first 31 days after birth, whether specific risk factors were associated with incidence of diarrhea in calves, and whether diarrhea was associated with weight gain of the calves.199910382026
uterine tubal cells remain uninfected after culture with in vitro-produced embryos exposed to bovine viral diarrhea virus.bovine viral diarrhea virus (bvdv) has been isolated from washed and sonicated, in vitro-produced embryos, but the infectivity of bvdv associated with intact, developing, embryos has not been demonstrated. the objective of this study was to determine if a dose of bvdv infective for co-culture cells was associated with individual, developing embryos, following artificial exposure to the virus and washing. in 5 replicates, zona pellucida-intact, in vitro-produced embryos were assigned to a negativ ...199910591493
ovine pestiviruses: their taxonomic status revealed by palindromic nucleotide substitutions.we examined previously identified border disease virus (bdv) strains by using a newly proposed genotyping procedure based on palindromic nucleotide substitutions (pns) in the 5'-untranslated region (utr), and found 22 (41.5%) out of 53 strains of bdv in the nucleotide sequence databases are not of bdv. all the 22 ovine pestivirus strains were allocated to the bvdv species according to the pns, and were compared with reference strains of pestivirus 1 (bvdv-ia,-ib, and-ic genovars), pestivirus 2 ( ...199910591495
serological and molecular diagnosis of bovine viral diarrhoea virus and evidence of other viral infections in dairy calves with respiratory disease in venezuela.an investigation based on 2 studies was carried out to assess the involvement of bovine virus diarrhoea virus (bvdv), bovine herpesvirus type 1 (bhv-1), and bovine respiratory syncytial virus (brsv) in calf respiratory disease in dairy farms in venezuela. in the first study, 8 farms were selected and paired serum samples from 42 calves with respiratory disease were tested by elisa for antibodies to the 3 viruses. seroconversion to bvdv, bhv-1, and brsv was found to 5, 2, and 6 farms out of the 8 ...199910605142
[inactivation of bvdv (experimental model for hepatitis c) using low ph and heat treatment in intravenous human immunoglobulins].to measure the capability of heat (60 degrees c for 10 hr) and low ph to inactivate bvdv (a model of hcv) in human intravenous immunoglobulins.199910618912
alteration of leukocyte populations in calves concurrently infected with bovine respiratory syncytial virus and bovine viral diarrhea virus.bovine viral diarrhea virus (bvdv) infection altered leukocyte populations in calves that were reflected by depression of t, bocd4+, and bocd8+ lymphocytes in the thymus and depression of b lymphocytes in peyer's patches (pp). the present study was based on mononuclear leukocyte preparations from eighteen 9- to 12-month-old crossbred calves that were each exposed to either bovine respiratory syncytial virus (brsv), bvdv, or brsv and bvdv concurrently, or served as mock-infected controls. periphe ...199910630791
virus safety of avital bone tissue transplants: evaluation of sterilization steps of spongiosa cuboids using a peracetic acid-methanol mixture.the aim of this study was to validate the virus-inactivating/eliminating capacity of the manufacturing process of spongiosa cuboids. both the sterilization step with peracetic acid (paa)/ethanol and the defatting step of bones with chloroform/methanol (2:1, v/v) were investigated. relevant enveloped, non-enveloped, and model viruses belonging to different virus families were included in the investigation: human immunodeficiency virus type 2 (hiv-2), hepatitis a virus (hav), poliovirus (pv-1), ps ...199910652175
infections with flaviviridae.the family of the flaviviridae contains 3 genera: (i) the hepaciviruses, to which belongs hepatitis c virus (hcv), (ii) the flaviviruses and (iii) the pestiviruses. over 140 million people, more than four times the number of hiv-positive individuals, are chronically infected with the hcv. hepatitis g virus (hgv) has not yet been assigned to a genus. the impact of this recently discovered virus is yet to be established. infections with flaviviruses such as yellow fever virus (yfv), dengue fever v ...199910655776
genetic analysis of pestiviruses at the 3' end of the genome.specific pcr primers were selected for each pestivirus genotype which flanked the 3'-part of the ns5b gene and more than three quarters of the 3'-utr. pcr products were sequenced in both directions using an automatic sequencing device and analyzed by computer package program dnastar. a comparative analysis of the 3' untranslated region (3'-utr) of 82 viruses, representing the four genotypes of the pestivirus genus, provided a similar phylogenetic grouping as other genomic regions. intertypic rec ...199910403696
benefits and risks due to animal serum used in cell culture production.infection with bovine viral diarrhoea virus (bvdv) and other viruses is frequent in the bovine population. in utero infection leads to virus and antibody contamination of foetal and other serum used in cell culture production. the use of contaminated cells for vaccine production may result in contaminated vaccines, which may lead to seroconversion or disease in the vaccinated animal. contaminated serum or cell cultures may also interfere with the diagnosis of viral infections. methods for the de ...199910404869
immunohistochemical demonstration of bovine viral diarrhoea virus antigen in the pancreatic islet cells of cattle with insulin-dependent diabetes mellitus.the pancreatic islets were studied in seven cattle with insulin-dependent diabetes mellitus (iddm) associated with persistent bovine viral diarrhoea virus (bvdv) infection. bvdv antigen was detected immunohistochemically in the pancreatic islet cells. there was a decrease in the size and number of islets, vacuolar degeneration of residual islet cells, and lymphocytic insulitis. the atrophied islets were composed of small uniform cells with limited amounts of cytoplasm, containing a small number ...199910405307
genetic clustering of bovine viral diarrhoea viruses in cattle farms: genetic identification and analysis of viruses directly from cattle sera.the herd-specific genetic clustering of bovine viral diarrhoea virus (bvdv) was studied by phylogenetic analysis of 42 sera collected between 1995-97 from persistently infected cattle on 16 farms in sweden. the viruses were typed by sequencing a part of the 5' untranslated region of the genome, which had been amplified directly from serum by reverse transcription-polymerase chain reaction. all of the viruses were of bvdv i, either bvdv ia (nadl-like) or bvdv ib (osloss-like) genotypes. no relati ...199910409414
health status of bulls used for natural breeding on farms in south west scotland.one hundred and nine breeding bulls were examined during the period november 1992 to june 1993 on farms in south west scotland for evidence of infectious diseases associated with breeding. preputial washings were collected to screen for campylobacter fetus venerialis, together with serial blood samples to assess their seroprevalence to bovine virus diarrhoea virus (bvdv), bovine herpes virus-1 (bhv-1), leptospira hardjo and bovine herpes virus-4 (bhv-4). the possible impact of natural mating on ...199910416365
detection of viral antigen in placenta and fetus of cattle acutely infected with bovine viral diarrhea virus.the reproductive organs and fetuses of seven norwegian red heifers were investigated for the presence of bovine viral diarrhea virus (bvdv) antigen during the time of initial transplacental transmission of the virus. the heifers were inoculated with a noncytopathogenic bvdv at day 85/86 of gestation and were slaughtered at day 7, 10, 14, 18, or 22 postinoculation (pi). cryostat sections of uterus, ovaries, placentomes, intercotyledonary fetal membranes, and fetal organs were examined using immun ...199910421093
differential cytokine responses of cd4+ and cd8+ t cells in response to bovine viral diarrhoea virus in cattle.virus-specific t cell responses were measured in cattle seropositive for bovine viral diarrhoea virus (bvdv) and compared with those from bvdv-seronegative animals. cd4+ and cd8+ t cells were purified and co-cultured in vitro with autologous, bvdv-infected monocytes over a time-course to assess the kinetics of the proliferative response. supernatants from parallel t cell cultures were harvested and the presence of the cytokines interleukin (il)-2, il-4 and interferon-gamma (ifn-gamma) were measu ...199910423135
recombinant adenoviruses expressing the e2 protein of bovine viral diarrhea virus induce humoral and cellular immune responses.the e2 protein of bovine viral diarrhea virus (bvdv) is a major viral glycoprotein and an attractive target for bvdv vaccines. three replication defective recombinant adenoviruses expressing the bvdv/e2 protein (rads/e2) were constructed. two contain a constitutive promoter, and one an inducible promoter. all three recombinant adenoviruses induced very strong bvdv specific antibody responses in a mouse model as detected by enzyme-linked immunosorbant assay (elisa) and neutralization tests. induc ...199910436933
induction of humoral and cellular immune responses against the nucleocapsid of bovine viral diarrhea virus by an adenovirus vector with an inducible promoter.a new recombinant adenovirus was constructed that expressed the nucleocapsid (c protein or p14) of the bovine viral diarrhea virus (bvdv) under the control of a tetracycline-regulatable promoter. mice covaccinated with this recombinant adenovirus, accompanied by another recombinant adenovirus expressing the trans-activator protein, induced a strong humoral immune response to the bvdv/c protein as detected by elisa. splenocytes from mice immunized with the recombinant adenovirus showed a specific ...199910441551
investigation of the immunological properties of the bovine viral diarrhea virus protein ns3 expressed by an adenovirus vector in mice.two replication-defective human adenovirus recombinants encoding the ns3 protein (p80) of bovine viral diarrhea virus (bvdv) under the control of a modified adenovirus major later promoter (bm5), radbm5/ns3, and human cytomegalovirus promoter (cmv5), radcmv5/ns3, were constructed. these two recombinant adenoviruses were tested for their expression of the ns3 protein in vitro in three different cell lines and also in vivo for the induction of bvdv-specific immune responses in mice. the recombinan ...199910446643
semiliki forest virus vector carrying the bovine viral diarrhea virus ns3 (p80) cdna induced immune responses in mice and expressed bvdv protein in mammalian cells.bovine viral diarrhea virus (bvdv) is a primary pathogen responsible for bovine enteric, respiratory and reproductive failure. a genetic region is encoding the p80 (ns3) of bvdv as the most conserved protein among pestiviruses. bvdv infection in cattle induces ns3 specific lymphocyte proliferation and humoral responses. to generate a dna vaccine against bvdv, the gene for bvdv-nadl ns3 was cloned into an eukaryotic expression vector of semiliki forest virus (psfv-1). quadriceps muscles of balb/c ...199910465327
susceptibility of bovine naked 2- and 4-cell embryos and hatched blastocysts produced in vitro to infection with noncytopathogenic bovine viral diarrhea virus.to investigate the susceptibility of early bovine embryos to noncytopathogenic bovine viral diarrhea virus (ncp bvdv), 2- and 4-cell embryos produced in vitro from which zona pellucida had been removed by pronase treatment, and hatched blastocysts were exposed to 10(6) tcid50/m/ of ncp bvdv no. 12 strain. the virus was detected in all embryo samples immediately prior to cultivation but not in the medium. after 24-hr culture, the virus was isolated from four media and two embryo samples in four e ...199910487236
genetic diversity of pestiviruses: identification of novel groups and implications for classification.the complete npro coding sequences were determined for 16 pestiviruses isolated from cattle, pig, and several wild ruminant species including reindeer, bison, deer, and bongo. phylogenetic analysis enabled the segregation of pestiviruses into the established species bovine viral diarrhea virus-1 (bvdv-1), bvdv-2, border disease virus (bdv), and classical swine fever virus (csfv). for bvdv-1 five distinct subgroups were identified, while bvdv-2, bdv, and csfv were each subdivided into two subgrou ...199910489341
effect of bovine herpesvirus-1 or bovine viral diarrhea virus on development of in vitro-produced bovine embryos.in previous experiments, zona pellucida (zp)-intact in vitro-produced (ivp) embryos incubated for 1 hr with 10(6.3) tcid(50)/ml bovine herpes virus-1 (bhv-1), 10(5.3) tcid(50)/ml cytopathic (cp) bovine viral diarrhea virus (bvdv) or 10(5.3) tcid(50)/ml noncytopathic (ncp) bvdv showed no signs of virus replication or embryonic degeneration. the aims of the present study were to investigate whether a prolonged presence (24 hr or 8 days) of 10(6.3) tcid(50)/ml bhv-1 or 10(5.3) tcid(50)/ml bvdv in a ...199910497347
an internal duplication in the 5' noncoding region of strain h: a bovine viral diarrhoea virus (bvdv) isolated from pigs.a pig pestivirus isolate, strain h, was characterized by using reverse transcription-pcr (rt-pcr) and direct sequencing of the amplicons. a duplication of 74 nucleotides was found at the 5' terminus of the 5' noncoding (nc) region, which was also found in rna isolates from tonsils from two other pigs from the same farm. when the duplication was omitted, the 5' nc region showed 97.8% similarity to bovine viral diarrhoea virus (bvdv) strain korevaar and 94% to bvdv strain osloss. furthermore, the ...199910499449
[selection of bvdv genotype ii isolates using a monoclonal antibody and facs analysis].the infection of cattle with the bovine viral diarrhea virus (bvdv) in germany is gaining attention and guidelines for the "protection of cattle farms against bvdv infections" were passed in 1997. new investigations about the damages induced by bvdv infections as well as the new occurrence of so-called bvdv genotypes (bvdv i and ii) made the problems to become aware. the newly described bvdv genotype considerably differs both genetically and antigenetically from the up to now known bvd-viruses ( ...199910507184
assignment of the multifunctional ns3 protein of bovine viral diarrhea virus during rna replication: an in vivo and in vitro study.studies on the replication of the pestivirus bovine viral diarrhea virus (bvdv) were considerably facilitated by the recent discovery of an autonomous subgenomic bvdv rna replicon (di9c). di9c comprises mainly the untranslated regions of the viral genome and the coding region of the nonstructural proteins ns3, ns4a, ns4b, ns5a, and ns5b. to assess the significance of the ns3-associated nucleoside triphosphatase/helicase activity during rna replication and to explore other functional features of ...199910516027
establishment and characterization of cytopathogenic and noncytopathogenic pestivirus replicons.defective interfering particles (dis) of bovine viral diarrhea virus (bvdv) have been identified and shown to be cytopathogenic (cp) in the presence of noncytopathogenic (noncp) helper virus. moreover, a subgenomic (sg) rna corresponding in its genome structure to one of those bvdv dis (di9) was replication competent in the absence of helper virus. we report here that an sg bvdv replicon which encodes from the viral proteins only the first three amino acids of the autoprotease n(pro) in addition ...199910516051
imino sugars inhibit the formation and secretion of bovine viral diarrhea virus, a pestivirus model of hepatitis c virus: implications for the development of broad spectrum anti-hepatitis virus agents.one function of n-linked glycans is to assist in the folding of glycoproteins 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, such as n-butyl-deoxynojirimycin (nb-dnj) and n-nonyl-dnj (nn-dnj), and this causes some proteins to be misfolded and retained within the endoplasmic reticulum (er). we have shown previously that the nn-dnj-induced misfolding o ...199910518544
seroprevalence to bovine virus diarrhoea virus and other viruses of the bovine respiratory complex in venezuela (apure state).six hundred and fifteen serum samples obtained from cows in five districts of apure state, venezuela, were tested by elisa for antibodies to bovine virus diarrhoea virus (bvdv). the same samples were also elisa-tested for antibodies to bovine herpesvirus type 1 (bhv-1) and bovine respiratory syncytial virus (brsv). additionally, the haemagglutination-inhibition (hi) test was used for detecting antibodies to parainfluenza virus type 3 (piv-3). overall, seroprevalence to bvdv was 36+/-7% (se); ser ...199910530426
nested reverse transcriptase-polymerase chain reaction (rt-pcr) for typing ruminant pestiviruses: bovine viral diarrhea viruses and border disease virus.a nested reverse transcription (rt) polymerase chain reaction (pcr) assay was evaluated for differentiating reference bovine viral diarrhea virus (bvdv) strains, bvdv from diagnostic accessions, modified-live virus (mlv) bvdv strains in bovine viral vaccines, and a reference border disease virus (bdv). the detection level of this assay was compared to viral infection in cell culture. the pcr assay was used to distinguish 3 ruminant pestiviruses, types 1 and 2 bvdv, and type 3 bdv. the consensus ...199910534007
genetic typing of bovine pestiviruses from england and wales.using rna purified directly from stored clinical specimens, a collection of 62 pestiviruses were typed by rt-pcr and sequencing within the 5'-untranslated region of the genome. all the specimens had been obtained in 1966/1967 from diary cattle in england and wales. eight further pestiviruses, grown in cell culture, were characterised in the same way. seven of these viruses were representatives of a panel of british isolates, obtained from cattle ten years before. the eighth was the virus used in ...199910535769
hepatitis c virus and other flaviviridae viruses enter cells via low density lipoprotein receptor.endocytosis of the flaviviridae viruses, hepatitis c virus, gb virus c/hepatitis g virus, and bovine viral diarrheal virus (bvdv) was shown to be mediated by low density lipoprotein (ldl) receptors on cultured cells by several lines of evidence: by the demonstration that endocytosis of these virus correlated with ldl receptor activity, by complete inhibition of detectable endocytosis by anti-ldl receptor antibody, by inhibition with anti-apolipoprotein e and -apolipoprotein b antibodies, by chem ...199910535997
pestivirus infection in small ruminants: virological and histopathological findings.pestivirus infection was detected in several flocks of sheep and goats located in the south of italy by means of serological, virological and histopathological investigations. from four animals, two lambs and two kids, showing enteric symptoms which died during the first week of life, four pestivirus strains were isolated and typed as bvdv-like (three isolates) and "tipic" bdv strains (one isolate). the histopathological lesions consisted of areas of hypomyelination in the brain, and a slight de ...199910555206
mutational analysis of bovine viral diarrhea virus rna-dependent rna polymerase.recombinant bovine viral diarrhea virus (bvdv) nonstructural protein 5b (ns5b) produced in insect cells has been shown to possess an rna-dependent rna polymerase (rdrp) activity. our initial attempt to produce the full-length bvdv ns5b with a c-terminal hexahistidine tag in escherichia coli failed due to the expression of insoluble products. prompted by a recent report that removal of the c-terminal hydrophobic domain significantly improved the solubility of hepatitis c virus (hcv) ns5b, we cons ...199910559328
effect of experimentally induced type ii bovine viral diarrhea virus infection on platelet function in calves.to evaluate platelet aggregation responses in calves experimentally infected with a thrombocytopenia-inducing type ii bovine viral diarrhea virus (bvdv) isolate (bvdv 890).199910566815
vaccination of cattle with a dna plasmid encoding the bovine viral diarrhoea virus major glycoprotein e2.bovine viral diarrhoea virus (bvdv) is an economically important pathogen of cattle that is ubiquitously distributed worldwide. in this study, cattle were immunized by intramuscular injections with plasmid dna expressing the bvdv type 1 major glycoprotein e2. animals either received injections of naked dna (n-dna) or dna in cationic liposomes (l-dna). both dna preparations induced virus-specific neutralizing antibodies in vaccinates, although the response was much lower in n-dna-immunized animal ...199910567644
serological survey for antibodies against selected infectious agents among fallow deer (dama dama) in central italy.sera were collected from 224 fallow deer (dama dama) in reserves in central italy. samples were tested for antibodies against chlamydia spp., brucella spp. and coxiella spp. with the complement fixation (cf) test. indirect immunofluorescence was used to test for antibodies against borrelia spp. and agglutination tests were conducted for leptospira interrogans antibodies. enzyme-linked immunosorbent assay (elisa) tests were used to detect antibodies against bovine herpesvirus-1 (bhv-1) and bovine ...199910574071
viremia and virus shedding in elk infected with type 1 and virulent type 2 bovine viral diarrhea virus.in order to determine whether elk (cervus elaphus) could be infected with and shed bovine viral diarrhea virus (bvdv) and to determine whether bvdv could cause disease in elk, two groups of five yearling elk each and two control cattle were experimentally inoculated intranasally with type 1 singer strain or a virulent type 2 isolate of bvdv, strain 24515. virulence of the type 2 isolate was confirmed by inoculation of a control bovine cow which developed diarrhea, dehydration, severe thrombocyto ...199910574525
expression of bovine viral diarrhoea virus glycoprotein e2 by bovine herpesvirus-1 from a synthetic orf and incorporation of e2 into recombinant virions.expression cassettes containing the codons for the pestivirus e (rns) signal peptide (sig) followed by a chemically synthesized orf that encoded the bovine viral diarrhoea virus (bvdv) strain c86 glycoprotein e2, a class i membrane glycoprotein, were constructed with and without a chimeric intron sequence immediately upstream of the translation start codon, and incorporated into the genome of bovine herpesvirus-1 (bhv-1). the resulting recombinants, bhv- 1/sige2(syn) and bhv-1/sige2(syn)-intron, ...199910580045
prevalence of bovine viral diarrhoea virus antibodies in india.a study was undertaken regarding the prevalence of bovine viral diarrhoea virus (bvdv) antibodies in bovine sera which tested negative for rinderpest and peste des petits ruminants virus antibodies. the samples were collected between january 1996 and december 1997. a total of 439 samples (327 cattle and 112 buffalo from 17 states of india) were tested using a commercial enzyme-linked immunosorbent assay (elisa) kit. the mean prevalence of bvdv antibodies in cattle was 15.29% (50/327) in 16 state ...199910588010
prevalence of bovine virus diarrhoea virus infection in belgian white blue cattle in southern belgium.a study was conducted in southern belgium to determine the prevalence of bovine viral diarrhoea virus (bvdv) infection in belgian white blue herds. blood samples were taken from 9685 cattle, representing all the stock on 61 farms, by local veterinarians to screen for persistently infected animals and to determine their serological status against bvdv. some of the herds (42.5%) were selected because of a prior positive diagnosis of bvdv or on the grounds of suspicion of bvd. a capture enzyme-link ...19999990704
epidemiological features and economical importance of bovine virus diarrhoea virus (bvdv) infections.infections with bovine virus diarrhoea virus (bvdv) are widespread throughout the world. although the prevalence of infection varies among surveys, the infection tends to be endemic in many populations, reaching a maximum level of 1-2% of the cattle being persistently infected (pi) and 60-85% of the cattle being antibody positive. persistently infected cattle are the main source for transmission of the virus. however, acutely infected cattle as well as other ruminants, either acutely or persiste ...199910028165
distribution of viral antigen in uterus, placenta and foetus of cattle persistently infected with bovine virus diarrhoea virus.the tissue distribution and cellular localisation of bovine virus diarrhoea virus (bvdv) was investigated in the uterus, placentomes, intercotyledonary foetal membranes and foetal organs of three persistently infected (pi) pregnant heifers. the uterus and ovaries of a non-pregnant pi heifer were also included in the study. cryostat sections were examined using immunohistochemical techniques and monoclonal antibodies against bvdv. a double immunofluorescence technique was used to identify bvdv po ...199910028166
laboratory diagnostic investigations for bovine viral diarrhoea virus infections in cattle.there are no pathognomonic clinical signs of infection with bovine viral diarrhoea virus (bvdv) in cattle. diagnostic investigations therefore rely on laboratory-based detection of the virus, or of virus-induced antigens or antibodies in submitted samples. in unvaccinated dairy herds, serological testing of bulk milk is a convenient method for bvdv prevalence screening. alternatively, serological testing of young stock may indicate if bvdv is present in a herd. in bvdv positive herds, animals pe ...199910028167
a simple, rapid and reliable enzyme-linked immunosorbent assay for the detection of bovine virus diarrhoea virus (bvdv) specific antibodies in cattle serum, plasma and bulk milk.to detect bovine virus diarrhoea virus (bvdv)-specific antibodies in cattle serum, plasma and bulk milk, a simple, reliable and rapid blocking elisa ("ceditest") has been developed using two monoclonal antibodies ("wb112" and "wb103") directed to different highly conserved epitopes on the non-structural peptide ns3 of pestiviruses. the test can be performed at high reproducibility using undiluted samples. in testing 1000 field serum samples, the elisa showed a specificity and a sensitivity relat ...199910028168
the detection of bovine viral diarrhoea virus in bulk milk samples by the use of a single-tube rt-pcr.a single step, single-tube reverse transcriptase-polymerase chain reaction (rt-pcr) test was developed to detect the presence of bovine viral diarrhoea virus (bvdv) in somatic cells from bulk milk samples. the test was configured using commercial kit-form rna extraction and rt-pcr procedures. the test was validated by examining bulk milk samples from approximately 80 herds with a history of bvdv and comparing results with those obtained from samples from a similar-sized control group. the test p ...199910028169
detection and genotyping of bovine diarrhea virus by reverse transcription-polymerase chain amplification of the 5' untranslated region.a reverse-transcription polymerase chain reaction (rt-pcr) was developed to differentiate the bovine diarrhea virus (bvdv) from other pestiviruses, and to determine the genotype of the bvdv isolates. for this purpose, primer pairs were selected in the 5' untranslated region (5'utr). the primers be and b2 were located in highly conserved regions and were pestivirus-specific. two primer pairs named b3b4 and b5b6 were specific of bvdv genotypes i and ii, respectively. with this technique, an amplif ...199910028170
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