| immunoperoxidase procedures for rapid detection of bovine viral diarrhea-mucosal disease virus antigen. | bovine viral diarrhea-mucosal disease (bvd-md) virus antigen was detected in bovine fetal muscular cells from sera of 42 cattle persistently infected with noncytopathic bvd-md virus by the indirect immunoperoxidase procedure (iip) but not from sera of 100 apparently healthy cattle. these findings agreed with the results obtained by the interference method. furthermore, bvd-md virus antigens were detectable in the smears of buffy coats by the iip procedure and in the formalin-fixed tissue section ... | 1994 | 7999919 |
| evaluation of pcr for diagnosis of bovine viral diarrhea virus in tissue homogenates. | tissue homogenates from 60 specimens submitted to the veterinary diagnostic center were evaluated by polymerase chain reaction (pcr) for detection of bovine viral diarrhea virus (bvdv). conventional virus isolation procedures showed the specimens contained bvdv. the bvdv rna was extracted from the homogenates and subjected to a reverse transcription reaction followed by pcr amplification. the pcr product was blotted onto a nylon membrane and hybridized with a 30-base pair oligonucleotide probe l ... | 1994 | 8011781 |
| porencephaly, hydranencephaly and leukoencephalopathy in ovine fetuses following transplacental infection with bovine virus diarrhoea virus: distribution of viral antigen and characterization of cellular response. | the distribution of viral antigen, histological lesions and inflammatory responses were examined in brains from ovine fetuses following experimental transplacental infection with a cytopathogenic strain of bovine virus diarrhoea virus (bvdv). at 10 and 14 days post inoculation (p.i.) viral antigen-containing cells were found throughout the different zones of the developing telencephalon and cerebellum. corresponding to the distribution of viral antigen, necrotic lesions both of already different ... | 1994 | 8017174 |
| natural recombination in bovine viral diarrhea viruses. | bvdv isolates exist as two biotypes differentiated at the molecular level by production of a p80 polypeptide. insertions consisting of host cell sequences and/or duplicated and rearranged viral sequences have been observed in the portion of the genome coding for the p80 polypeptide in some, but not all, cytopathic bvdv. the significance of these insertions to biotypic expression has yet to be demonstrated. it has been hypothesized that recombination results in the production of the p80 polypepti ... | 1994 | 8032255 |
| [bovine virus diarrhea/mucosal disease: a review]. | infections with the bovine viral diarrhea/mucosal disease virus (bvdv) are widespread and cause a variety of diseases including reproductive disorders, abortion and malformation, pneumoenteritis, thrombocytopenia and mucosal disease. together with the closely related border disease virus of sheep (bdv) and european swine fever virus (csfv), also referred to as hog cholera virus, bvdv is now classified in the genus pestivirus of the flaviviridae family. the bvdv exists in two biotypes, noncytopat ... | 1994 | 8036482 |
| identification of a new group of bovine viral diarrhea virus strains associated with severe outbreaks and high mortalities. | new bvdv strains associated with very high mortalities, which killed about 25% of the veal calves in quebec in 1993, have been isolated. in this study, characterization of the last two-thirds of the 5' untranslated region (5'utr) of their genome and virus neutralization experiments with polyvalent antisera raised in different animals both demonstrated that these strains formed a distinct group. despite a difference of about 25% in the 5'utr sequence with that of the classical strains, these 5'ut ... | 1994 | 8053150 |
| severe disease in adult dairy cattle in three uk dairy herds associated with bvd virus infection. | during 1993 outbreaks of diarrhoea in adult dairy cows in three geographically unrelated herds were found to be caused by bovine viral diarrhoea virus (bvdv). the affected animals showed signs of acute watery diarrhoea, agalactia and pyrexia (39.4 to 42 degrees c). ulceration of the buccal mucosa, a mucoid nasal discharge and stiffness were inconsistent signs. the disease spread rapidly in each case. the diagnosis was confirmed by the isolation of non-cytopathic bvdv from blood and tissues and b ... | 1994 | 8059512 |
| inactivation of hepatitis c virus in low ph intravenous immunoglobulin. | the safety from hepatitis c virus of intravenous immunoglobulin prepared by the cold ethanol method of cohn-oncley is demonstrated by clearance through the manufacturing process of 9 x 10(6) plaque-forming units of bovine viral diarrhea virus used as a surrogate for hepatitis c virus. incubation of the intravenous immunoglobulin in its final formulation at ph 4.25 for 21 days at 21 degrees c caused a 10,000-fold decrease in bovine viral diarrhea virus intentionally added and complete inactivatio ... | 1994 | 8068309 |
| enzyme-linked immunosorbent assay assessment of bovine viral diarrhea virus antigen in inactivated vaccines using polyclonal or monoclonal antibodies. | an enzyme-linked immunosorbent assay (elisa) procedure was developed to assay the cytopathic and noncytopathic bovine viral diarrhea (bvd) virus strains used in inactivated vaccines licensed by the united states department of agriculture. the assay uses a biotin-labeled, staphylococcal protein a purified polyclonal bvd antibody (bab) from a calf hyperimmuned against nadl, singer, c24v, new york-1 (ny-1) strains and a field isolate. the bab recognized the following reference strains of bvd virus: ... | 1994 | 8068310 |
| investigation of an outbreak of mucosal disease in a beef cattle herd in southwestern saskatchewan. | this study describes the epidemiological investigation of an outbreak of mucosal disease that occurred on a ranch in southwestern saskatchewan. over a six month period during the fall and winter of 1991-1992,in a herd of 515 beef cattle and 96 bison, 20 yearling cattle from a group of 105 housed in one feedlot pen died from mucosal disease. a further eight yearlings were slaughtered for salvage because they were at risk of dying from mucosal disease. mucosal disease mortalities were the first ob ... | 1994 | 8076288 |
| morbidity and mortality in a large irish feedlot; microbiological and serological findings in cattle with acute respiratory disease. | a survey of morbidity and mortality was undertaken in a slatted unit containing 6399 beef cattle over a 6 month period. the mortality rate was 0.78% and the morbidity rate was 12.7%. the interval from arrival to morbidity was 25.5 days +/- 0.9. significantly more sick cattle were identified on either mondays or tuesdays than were seen on saturdays or sundays (p < 0.005). the mean interval to mortality (all diseases) was 48.5 days +/- 7.4. respiratory disease was the most frequently recorded dise ... | 1993 | 8111615 |
| validation of virus inactivation and removal for the manufacturing procedure of two immunoglobulins and a 5% serum protein solution treated with beta-propiolactone. | intravenous immunoglobulins and serum protein solutions are manufactured from human plasma pools of healthy, screened donors. a step-by-step validation of virus removal and/or inactivation was performed for the manufacturing process, which includes cold ethanol fractionation, beta-propiolactone (beta-pl) treatment, uv irradiation, thermal inactivation and other chemical and physical purification steps. the total viral clearance factors achieved for the entire manufacturing process were by severa ... | 1993 | 8117439 |
| [prevalence of antibodies against the viruses of european swine fever, aujeszky's disease and "porcine reproductive and respiratory syndrome" in wild boars in the federal states sachsen-anhalt and brandenburg]. | during the hunting season from 1991/1992 blood samples were collected from wild boar shot in the federal states of sachsen-anhalt (482 samples) and brandenburg (177 samples) which corresponds to 2.1 and 0.4% of the total hunting bag. all sera were screened in a complex trapping blocking (ctb) elisa for antibodies against hog cholera virus (hcv) and in an indirect elisa for antibodies against aujeszky's disease virus (adv). additionally the sera were tested for neutralizing antibodies against hcv ... | 1994 | 8131731 |
| monoclonal antibodies to bovine viral diarrhea virus: cross-reactivities to field isolates and hog cholera virus strains. | monoclonal antibodies to bovine viral diarrhea virus (bvdv) were examined for binding with a large number of north american bvdv isolates and eight strains of the serologically related pestivirus, hog cholera virus (hcv). no single bvdv monoclonal antibody reacted with all bvdv isolates. the most cross-reactive monoclonal antibody was an anti-p80/p125 antibody which showed a positive reaction with 173 of 180 (96%) north american isolates. from a fewer number of isolates tested, one anti-gp53 mon ... | 1994 | 8143258 |
| pathogenesis of mucosal disease: a cytopathogenic pestivirus generated by an internal deletion. | cytopathogenic bovine viral diarrhea virus (bvdv) arises by rna recombination in animals persistently infected with noncytopathogenic bvdv. such animals develop fatal mucosal disease. in this report, the genome of a cytopathogenic bvdv isolate, termed cp9, is characterized. cp9-infected cells contained not only viral genomic rna of 12.3 kb but also a bvdv-specific rna of 8 kb. cdna cloning and sequencing revealed that the 8-kb rna is a bvdv genome with an internal deletion of 4.3 kb. the 8-kb rn ... | 1994 | 8151789 |
| detection of bovine viral diarrhoea virus p80 protein in subpopulations of bovine leukocytes. | flow cytometry and two-colour immunofluorescence were used to detect cytoplasmic bovine viral diarrhoea virus (bvdv) antigen in leukocytes from viraemic cattle. monoclonal antibody to the p80 protein of bvdv, a non-structural viral antigen, was used to identify the subpopulations of leukocytes in which viral protein synthesis had occurred. viral antigen was detected in 23% of peripheral blood mononuclear cells. monocytes were found to have the highest frequency of infection (35%). a higher propo ... | 1994 | 8176381 |
| cloning, sequencing, and in vitro expression of glycoprotein gp48 of a noncytopathogenic strain of bovine viral diarrhea virus. | total cellular and viral rna isolated from cells infected with noncytopathic bovine viral diarrhea virus (bvdv) strain 2724 was used for reverse transcription of viral specific sequences encoding the putative signal sequence and protein-encoding region of gp48. the cdna template was amplified twice by the polymerase chain reaction with a nested set of primers designed from nucleotide sequences of cytopathic bvdv strains nadl and 72, and ligated into a plasmid vector. nucleotide sequence analysis ... | 1994 | 8203115 |
| border disease virus transmitted to sheep and cattle by a persistently infected ewe: epidemiology and control. | in a swedish sheep flock comprising 202 ewes and 13 rams, a pair of twin lambs born in the spring of 1990 demonstrated signs of border disease (bd) and were persistently infected (pi) with border disease virus (bdv). investigation showed that bdv had been introduced in the preceding tupping period 5-6 months earlier by a bought-in ewe which, on the basis of immunoperoxidase- and polymerase chain reaction techniques, was shown to be pi with bdv. only 7 of the ewes, all of which had been in close ... | 1994 | 8209823 |
| associations between viral infections and respiratory disease in artificially reared calves. | market-purchased, week-old, dairy bred calves entering a commercial calf-rearing unit were blood sampled at six-week intervals until three months old. viral infections were monitored by elisa for antibodies to bovine herpesvirus 1, bovine respiratory syncytial virus, parainfluenzavirus-3, bovine adenovirus subgroup 1 and bovine viral diarrhoea virus (bvdv). the immunoperoxidase test was used to detect bvdv in serum. the total immunoglobulin concentration in the initial blood sample was measured ... | 1993 | 8212494 |
| processing of poly-ubiquitin in the polyprotein of an rna virus. | the rna genome of several cytopathogenic (cp) strains of the pestivirus bovine viral diarrhea virus (bvdv) contains ubiquitin coding sequences (ucs). in noncytopathogenic bvdv strains, such insertions are missing. gene expression of bvdv occurs via synthesis of a polyprotein which is subsequently processed by virus-encoded and cellular proteases. the insertion of ucs in the genomes of cpbvdv strains cp14 and osloss leads to additional cleavages in the viral polyprotein. the respective processing ... | 1993 | 8212597 |
| application of a blocking enzyme-linked immunosorbent assay for serological monitoring of hog cholera (classical swine fever) in poland. | between 1990 and 1992, serum samples from 55,478 domestic swine were tested by enzyme-linked immunosorbent assay (elisa) for the presence of hog cholera virus (hcv) antibodies. the amount of antibody in the sera was expressed as the mean percentage inhibition (pi). for diagnosis, the tested sera were diluted 1:2 and considered positive if the pi was less than 25%. sera giving pi values in the range of 25-50% were retested against hcv and bovine virus diarrhoea virus (bvdv), by neutralising perox ... | 1993 | 8219338 |
| molecular characterization of positive-strand rna viruses: pestiviruses and the porcine reproductive and respiratory syndrome virus (prrsv). | molecular characterization has become an important tool for the analysis of viruses including their classification. the manuscript focuses on the molecular analysis of two members of the genus pestivirus (hog cholera virus, hcv and bovine viral diarrhea virus, bvdv) and of the recently discovered porcine reproductive and respiratory syndrome virus (prrsv). the first protein encoded within the single large pestivirus orf is a nonstructural protein with autoproteolytic activity. the cleavage site ... | 1993 | 8219812 |
| serological and antigenical findings indicating pestivirus in man. | an epidemiological survey for pestivirus was undertaken in zambia and europe, in view of the recent serological findings obtained by previous studies in europe with humans. collected sera were tested for anti-bovine viral diarrhea virus (bvdv) specific antibodies by iif and western blotting. of those individuals tested (n = 1272), 15.3% showed a seropositive reaction to the bvdv. anti-bvdv antibody prevalence in immuno-depressed patients (e.g. hiv positive) was investigated. a higher prevalence ... | 1993 | 8219813 |
| relationship between the levels of antibodies to bovine viral diarrhoea virus in bulk tank milk and the prevalence of cows exposed to the virus. | a positive relationship was found between the prevalence of cows in a herd which were antibody-positive for bovine viral diarrhoea virus (bvdv) and the level of antibodies to the virus in bulk tank milk as determined by an indirect enzyme-linked immunosorbent assay (elisa). in herds with an elisa absorbance value of up to 0.20 there were very few or no antibody-positive cows, whereas in herds with an elisa absorbance value of at least 0.81, 87 to 100 per cent of the lactating cows were antibody- ... | 1993 | 8236677 |
| comparative hybridization and nucleotide sequence information from two noncytopathic isolates of bovine viral diarrhea virus. | comparative hybridizations of 8 cytopathic (cp) and 11 noncytopathic (ncp) isolates of bovine viral diarrhea virus (bvdv) were done using 4 different cdna hybridization probes. the hybridization probes were prepared from cdna synthesized from 1 cp bvdv (nadl) and 2 ncp bvdv isolates (sd-1 and ny-1) within the p80 region and from cdna spanning the 5' untranslated region of ncp sd-1. hybridization with the 5'/sd-1 probe detected 19 out of 19 isolates, whereas the p80/nadl, p80/ny-1 and p80/sd-1 hy ... | 1993 | 8236781 |
| prolonged persistence of cytopathogenic bovine viral diarrhea virus (bvdv) in a persistently viremic cattle. | a bull persistently viremic with noncytopathogenic (ncp) bvdv was inoculated with the cytopathic (cp) bvdv strain tgac, which had been found to be antigenically different from the endogenous ncpbvdv (ncpw8). neutralizing antibodies against strains nadl and tgac were detectable 12 days and four weeks post infection, respectively. the animal developed fever and diarrhea 15 weeks post infection. on days 3 and 8 after onset of diarrhea a cpbvdv (cpx) was isolated from feces. antigenic analysis using ... | 1993 | 8237210 |
| the nucleotide sequence of the 5'-untranslated region of bovine viral diarrhoea virus: its use as a probe in rapid detection of bovine viral diarrhoea viruses and border disease viruses. | a 289 bp cdna fragment from the 5'-untranslated region (utr) of 16 bovine viral diarrhoea virus (bvdv) isolates was amplified by reverse transcription and polymerase chain reaction, and sequenced by dideoxy dna sequencing. the sequence showed greater than 90% homology between the isolates and bvdv nadl in this region, and greater than 97% homology within a 72 base sub-region (nt 314-386). the 289 bp fragment was then used as a probe for rapid detection of bvdv and border disease virus (bdv) from ... | 1993 | 8264668 |
| estimation of herd incidence of infection with bovine virus diarrhoea virus (bvdv) in herds previously without animals persistently infected with bvdv. | on a previous occasion, all animals in 9 herds had been bled for bovine virus diarrhoea virus (bvdv) and antibodies. no animals persistently infected (pi) with bvdv were detected. three years later 10 animals in each herd were tested again. by this time 60 out of 90 previously seronegative animals had seroconverted. seroconversions had occurred in 8 of the 9 herds corresponding to a incidence risk of herd infection of 0.52 per year. the incidence risk of seroconversions in individual animals was ... | 1993 | 8266890 |
| attempts at preventing further spread of bovine virus diarrhoea virus (bvdv) infection in 5 danish dairy herds in which bvdv had been isolated. | in 5 herds in which bovine virus diarrhoea virus (bvdv) had been isolated, all animals were bled for virological and serological examination. after the herd blood test, follow up blood tests were made on calves born up to 6 months later in 1 herd, 9 months later in 1 herd and up to 12 months later in 3 herds. persistently infected animals (pi animals) were removed and after a time period a small herd sample of 10 animals that were born after removal of the pi animals were examined for bvdv antib ... | 1993 | 8266891 |
| prevaccination bovine viral diarrhea virus titers and subsequent reproductive performance in dairy heifers. | the study was conducted to determine if there was a relationship between prevaccination bovine viral diarrhea virus (bvdv) titers in 14 month-old dairy heifers and time open during first lactation, length of the conception interval, fetal survival during the second pregnancy, and age at culling. possible associations were analyzed using nonparametric survival methods and survival distributions were described using the product-limit (kaplan meier) methods. regression analysis was used to estimate ... | 1993 | 8269361 |
| epidemiological study of enzootic pneumonia in dairy calves in saskatchewan. | a field study involving 325 calves from 17 dairy herds in saskatchewan was conducted to determine the risk of enzootic pneumonia and to assess its association with a number of factors. two different case definitions of pneumonia were used in the analyses: the first was based on producers' treatment risk (case1) and the second was based on semimonthly clinical examinations of calves by the research veterinarian (case2). the risk of pneumonia based on case1 was 39% and on case2 was 29%. the measur ... | 1993 | 8269363 |
| viral antibodies in bovine fetuses in argentina. | in order to establish the prevalence of viral infections of the bovine fetus in argentina, a serological survey for antibodies against viral agents currently affecting cattle in this country was conducted. antibodies against foot-and-mouth disease virus (fmdv), bovine herpesvirus-1 (bhv-1), bovine leukaemia virus (blv), bovine rotavirus (brv), bovine coronavirus (bcv), bovine viral diarrhoea virus (bvdv) and parainfluenza-3 (pi-3) were investigated in a total of 315 fetal serum samples. conventi ... | 1993 | 8284507 |
| molecular characterization of border disease virus, a pestivirus from sheep. | three serologically different pestivirus strains isolated from sheep were selected for molecular analysis. cdna and deduced amino acid sequences of the genomic regions encoding glycoproteins e1 and e2 were obtained from the three strains. a comparison with amino acid sequences of bovine viral diarrhea virus (bvdv) and classical swine fever virus (csfv) revealed that one of the three ovine pestivirus strains can be grouped together with bvdv. the other two strains, however, were clearly different ... | 1994 | 8291236 |
| immune response to other agents of calves persistently infected with bovine virus diarrhoea virus (bvdv). | the ability of calves persistently infected (pi) with bovine virus diarrhoea virus bvdv to respond immunologically to defined antigens other than bvdv was studied. five clinically healthy pi calves were studied together with 5 non-pi calves serving as controls. the humoral immune response was tested by measuring the serum antitoxin titre following immunization against tetanus. the cellular immune response was tested by the ability to develop a positive reaction in a cutaneous tuberculin test per ... | 1993 | 8310903 |
| identification of the cell surface receptor for bovine viral diarrhoea virus by using anti-idiotypic antibodies. | we have produced and characterized polyclonal anti-idiotypic antibodies (anti-ids) that mimic the antigenic structures of gp53 from bovine viral diarrhoea virus (bvdv). in this study, the anti-ids were used to identify cell receptors for bvdv. the anti-ids bound specifically to bovine cells, as determined by flow cytometric analysis, and inhibitory binding assays showed that they bound to the cell surface receptors for bvdv. a cell surface protein with an m(r) of approximately 50k was immunoprec ... | 1993 | 8380838 |
| rna-stimulated ntpase activity associated with the p80 protein of the pestivirus bovine viral diarrhea virus. | the genomic rna of pestiviruses contains a single large open frame coding for virion structural proteins and viral nonstructural polypeptides. based on the presence of specific amino acid sequence motifs, pestivirus nonstructural protein p80 was predicted to be both a serine-type proteinase and a nucleoside triphosphatase (ntpase)/rna helicase. we previously demonstrated p80 possesses the former activity (wisherchen and collett, virology 184, 341-350, 1991). here, we provide experimental evidenc ... | 1993 | 8382392 |
| clinical, virological and serological findings after intranasal inoculation of pigs with bovine viral diarrhoea virus and subsequent intranasal challenge with hog cholera virus. | five groups of weaner pigs were intranasally inoculated with constant doses of bovine viral diarrhoea virus (bvdv) strain osloss/2482. four weeks post primary inoculation (p.p.i.) the animals were intranasally challenged with decreasing doses of hog cholera virus (hcv) strain alfort/187. clinical signs were not observed apart from a short febrile period (2 days, > 40 degrees c) in one animal. another animal died intercurrently without showing any pathological signs. virus isolation from leucocyt ... | 1993 | 8384395 |
| presumptive diagnostic differentiation of hog cholera virus from bovine viral diarrhea and border disease viruses by using a cdna nested-amplification approach. | hog cholera virus (hcv), bovine viral diarrhea virus (bvdv), and border disease virus (bdv) are closely related pestiviruses. bvdv and bdv are found worldwide but seldom cause disease in swine. in contrast, hcv has been successfully eradicated from swine in several nations but poses a potentially devastating threat to them because of its great virulence. rapid differential diagnosis of hcv from bvdv and bdv infections in swine is vital for detection of the possible reintroduction of hcv into nat ... | 1993 | 8384625 |
| rna insertions and gene duplications in the nonstructural protein p125 region of pestivirus strains and isolates in vitro and in vivo. | sixteen cytopathogenic (cp) bovine viral diarrhea virus (bvdv) strains/isolates were screened for the existence of rna insertions in the p125 gene region and/or for p80 gene duplications using the polymerase chain reaction after reverse transcription. three strains/isolates were shown to contain insertions, and in three others gene duplications were demonstrated. one strain was shown to contain a gene duplication in addition to an insertion. insertions or duplications were absent in the genomes ... | 1993 | 8384762 |
| induction of mucosal disease in cattle persistently infected with noncytopathic bovine viral diarrhea-mucosal disease virus by superinfection with cytopathic bovine viral diarrhea-mucosal disease virus. | three head of cattle persistently infected with noncytopathic bovine viral diarrhea-mucosal disease virus (ncbvd-mdv) were superinfected naturally or experimentally with cytopathic bovine viral diarrhea-mucosal disease virus (cbvd-mdv). in the naturally superinfected case, one animal manifested pyrexia and severe diarrhea, and died without developing antibodies to cbvd-mdv. however, another animal survived with only continual slight anorexia and pyrexia, and developed strong resistance to the su ... | 1993 | 8384896 |
| comparison of nucleic acid hybridization and nucleic acid amplification using conserved sequences from the 5' noncoding region for detection of bovine viral diarrhea virus. | primers and probes derived from conserved sequences located in the 5' noncoding region of pestiviruses were evaluated for detection of bovine viral diarrhea virus. with these reagents, hybridization and polymerase chain reaction tests detected 62 of 90 and 90 of 90 bovine viral diarrhea virus isolates, respectively. a quick lysis method for preparing rna for use in polymerase chain reaction amplification also was evaluated. | 1993 | 8385157 |
| presence of bovine viral diarrhoea virus in lymphoid cell populations of persistently infected cattle. | cattle infected in utero with bovine viral diarrhoea virus (bvdv) often develop a lifelong persistent infection (pi). during this pi, bvdv infects many cell types including peripheral blood mononuclear cells (pbmnc). to define the lymphoid cell populations in which bvdv persists pbmnc subpopulations were separated using monoclonal antibodies to cell surface markers. separated cells were analysed by a sensitive pcr assay for bvdv, in conjunction with flow cytometry to identify antigen-containing ... | 1993 | 8388020 |
| detection of hog cholera virus and differentiation from other pestiviruses by polymerase chain reaction. | reverse transcription coupled with the polymerase chain reaction (rt-pcr) was used for the detection and differentiation of pestiviruses. for this purpose, one primer pair was selected from a highly conserved region of the genome of pestiviruses. using these primers (pest 1-pest 2), dna fragments of between 72 and 74 bp could be amplified from all pestivirus isolates tested. in order to differentiate hog cholera virus (hcv) from bovine viral diarrhea virus (bvdv) and border disease virus (bdv), ... | 1993 | 8388887 |
| investigation of an epizootic of bovine viral diarrhea virus infection in calves. | eight of 19 calves born to bovine viral diarrhea virus (bvdv)-negative and -immunocompetent dams were determined to be infected with a noncytopathic strain of bvdv. six of the 8 calves had diarrhea and 2 had no clinical signs of disease. in 3 euthanatized calves, lesions consistent with mucosal disease were found throughout the gastrointestinal tract, and the virus was isolated from the spleen, lymph nodes, and small intestine. in 5 calves, bvdv was isolated from mononuclear cells in blood sampl ... | 1993 | 8391523 |
| expression of the bovine viral diarrhoea virus osloss p80 protein: its use as elisa antigen for cattle serum antibody detection. | the putative gene encoding the cytopathic bovine viral diarrhoea virus (bvdv) osloss strain p80 protein was amplified by pcr and inserted into a t7 promoter-based vector for expression in escherichia coli. bacterial expression led to cytoplasmic insoluble inclusion bodies which were denatured by urea treatment and renatured by dialysis. rabbit antisera were raised against this p80 recombinant antigen and assayed for the immunoprecipitation of either p120 or p80 protein from cytopathic or non-cyt ... | 1993 | 8393083 |
| nucleotide sequence of the bovine viral diarrhoea virus osloss strain: comparison with related viruses and identification of specific dna probes in the 5' untranslated region. | the nucleotide sequence of the cytopathic osloss isolate of bovine viral diarrhoea virus (bvdv) was deduced from overlapping cdna clones and from pcr products. the osloss genome is an rna molecule of positive polarity containing 12,480 nucleotides and having the capacity to code for a polyprotein of 3975 amino acids. the presence of the previously described internal stop codon in this viral sequence was disproved after direct sequencing of the appropriate pcr-amplified fragment. except for the p ... | 1993 | 8393084 |
| studies on the decline of bovine virus diarrhoea virus (bvdv) maternal antibodies and detectability of bvdv in persistently infected calves. | | 1993 | 8393612 |
| [in vitro amplification of genome fragments of the mucosal disease virus (bvd-md) using the pcr method]. | dna in-vitro amplification when a pcr (polymerase chain reaction) method is used (saiki et al., 1985) provides for a simple technique of marked amplification of a selected dna fragment. the length of a dna amplified fragment is determined by two synthetic primers which spontaneously (at an appropriate temperature) hybridize with the opposite ends of antiparallelly oriented strains of denatured dna. the enzyme taq polymerase completes the synthetisation of new dna strains from the primers. repeti ... | 1993 | 8394038 |
| a long term epidemiological study of bovine viral diarrhoea infections in a large herd of dairy cattle. | epidemiological aspects of bovine viral diarrhoea virus (bvdv) infections were studied longitudinally in a large dairy herd for three years. at the start of the study, practically all the cows more than four years old had bvdv antibody titres, whereas the younger stock were almost all seronegative. the spread of the virus was monitored in a part of the population that contained only transiently viraemic cattle and in another part that contained persistently viraemic calves. among the lactating c ... | 1993 | 8394609 |
| diagnosis of bovine virus diarrhoea by two enzyme-linked immunosorbent assays. | two enzyme-linked immunosorbent assays (elisas) for the diagnosis of bovine virus diarrhoea (bvd) are described: chekit-bvd-virus and chekit-bvd-sero. the first test detects virus antigen in leucocytes, resulting in identification of persistently-infected animals, while the second detects antibodies to bvd virus (bvdv). it is well known that even persistently-infected animals may have antibodies to heterologous bvdv strains. these animals are still negative to the chekit-bvd-sero test because of ... | 1993 | 8400386 |
| five hours to identify immunotolerant cattle, persistently infected with bovine virus diarrhoea virus. | detection of animals which are persistently-infected with bovine virus diarrhoea virus (bvdv) is of prime importance in the control of pestivirus infections in cattle, as these animals constitute the main reservoir of the virus. identification of such animals can be readily performed using crude whole blood samples with a sandwich enzyme-linked immunosorbent assay (elisa) requiring only approximately five hours. this elisa uses a combination of monoclonal antibodies as the capture agent and an i ... | 1993 | 8400388 |
| antibody prevalence of hog cholera, bovine viral diarrhoea and aujeszky's disease virus in wild boars in northern germany. | during the hunting season 1990/1991 a total of 841 blood samples was collected from shot wild boar corresponding to about 2.11% of the total hunting bag in lower saxony. all the sera were screened for neutralizing antibodies (nab) to hog cholera virus (hcv) and bovine viral diarrhoea virus (bvdv) by direct neutralizing peroxidase linked antibody (npla) assay. for the detection of antibodies (ab) against hcv a complex trapping blocking (ctb) elisa was used. cytotoxic sera were retested using an i ... | 1993 | 8404524 |
| experimental and spontaneous mucosal disease of cattle: a validation of koch's postulates in the definition of pathogenesis. | the complex etiology of mucosal disease of cattle has been unravelled by experimental reproduction of the fatal syndrome, thereby validating koch's postulates. the causal virus, bovine virus diarrhea virus (bvdv), has two biotypes, noncytopathogenic and cytopathogenic; the former can infect the early bovine fetus, induce immunotolerance and a lifelong persistent viremia (pv), whereas the latter biotype can superinfect the pv cattle and induce mucosal disease. the cytopathogenic biotype appears a ... | 1993 | 8407250 |
| detection of bovine viral diarrhea virus rna in formalin-fixed, paraffin-embedded brain tissue by nested polymerase chain reaction. | isolation and amplification of rna from formalin-fixed, paraffin-embedded tissues is delicate due to its fragility and ubiquitous ribonucleases. for retrospective studies, however, a convenient procedure for the detection of rna in archived material is of great value. bovine viral diarrhea (bvd) virus is a member of the pestivirus genus in the family flaviviridae. different protocols for the isolation of bvd virus rna from fresh and autolytic as well as from routinely formalin-fixed and paraffin ... | 1993 | 8408445 |
| recent advances in bovine vaccine technology. | a description of new commercial and experimental vaccines for viral and bacterial diseases of cattle can be broadly divided into those used for both beef and dairy cows and those used predominantly in dairy cattle. for both types of cattle, newer and experimental vaccines are directed against several of the important viral (e.g., bovine herpesvirus 1, bovine viral diarrhea virus, bovine respiratory syncytial virus, parainfluenza type 3, and foot-and-mouth disease virus) and bacterial pathogens ( ... | 1993 | 8408872 |
| fatal bvdv infection in adult cattle. | | 1993 | 8465509 |
| enhanced replication of orbiviruses in bovine testicle cells infected with bovine viral diarrhoea virus. | bovine testicle (bt) cells infected with non-cytopathogenic (ncp) bovine viral diarrhoea virus (bvdv) developed cytopathogenic effect (cpe) after superinfection with 7 orbiviruses, whereas no cpe was induced by them in the absence of ncp bvdv infection. the cpe was accompanied by the enhanced replication of orbiviruses. seven of 10 strains of ncp bvdv induced the enhanced replication of ibaraki virus, a member of orbivirus. these 7 strains of ncp bvdv were end phenomenon positive. in contrast, t ... | 1995 | 8519897 |
| protection of the bovine fetus from bovine viral diarrhoea virus by means of a new inactivated vaccine. | a model is described for the validation of vaccines designed to protect the bovine fetus from bovine viral diarrhoea virus (bvdv). the fetopathic nature of the challenge strain of virus was confirmed and the method used to test a commercial vaccine (bovidec) developed from a compton prototype. heifers were vaccinated two or three times about the time of impregnation and challenged when they were between 25 and 80 days of gestation. there was no evidence of a viraemia in the heifers after the cha ... | 1995 | 8533232 |
| rapid and sensitive detection of the bovine viral diarrhea virus genome in semen. | a reverse transcription-polymerase chain reaction (rt-pcr) procedure was developed for the detection of bovine viral diarrhea virus (bvdv) in cell culture supernatant and in bovine semen. several sets of primers, pcr conditions and extraction methods were examined to optimize the procedure. a set of primers designed to amplify a highly conserved portion of the p80 gene from bvdv (corresponding to nadl strain sequence from bp 6668 to 7107), was demonstrated to be the most effective. these oligonu ... | 1995 | 8537459 |
| experimentally induced "late-onset" mucosal disease--characterization of the cytopathogenic viruses isolated. | antigenic and genetic analyses were performed in order to establish relationships between the noncytopathogenic (ncp) and the cytopathogenic (cp) bovine viral diarrhoea viruses (bvdv) involved in the induction of a case of experimentally induced "late-onset" mucosal disease (md) symptoms. the persistent ncpbvdv, the cpbvdv used for superinfection (strain tgac) and the virus isolates from faeces (cpx) were examined using an immunoplaque test (ipt) to distinguish between cp and ncp virus populatio ... | 1995 | 8545967 |
| characterization of the hog cholera virus 5' terminus. | hog cholera virus (hocv) 5' terminus of the ald and gpe(-) strains were analyzed by using rapid amplification of cdna end method (5'race). an additional nine nucleotides were found at the 5' termini of genomic rna in the ald and gpe(-) strains of hocv. these nine nucleotides were also conserved in bvdv and were suggested to form a hairpin structure at the 5' terminus by computer-assisted analysis. it seems possible that the secondary structure and/or the 5' terminus sequence has a significant ro ... | 1995 | 8560779 |
| experimental mucosal disease in cattle: changes of lymphocyte subpopulations in peyer's patches and in lymphoid nodules of large intestine. | changes in the number and distribution of lymphocyte subtypes were investigated in peyer's patches in the jejunum and ileum, and mucosa-associated lymphoid nodules in the proximal colon and rectum of cattle with end-stage mucosal disease. mucosal disease had been induced experimentally in seven of 13 animals by inoculation with cytopathogenic bovine viral diarrhea virus (cp bvd-virus). for comparison, six clinically healthy, persistently viremic cattle were used. igm+, iga+, bocd4+, bocd8+ and g ... | 1995 | 8578683 |
| a nested polymerase chain reaction assay to differentiate pestiviruses. | viruses that comprise the pestivirus genus cause significant losses to the livestock industry. based on sequence analysis, currently 4 distinct genotypes are identified of which 3 infect cattle and sheep. distinguishing between bovine and ovine isolates by serological tests has often been difficult because of a high degree of cross reactivity. in this study, a nested polymerase chain reaction (pcr) assay was developed to identify and distinguish between bovine viral diarrhea virus (bvdv) type i, ... | 1995 | 8578861 |
| comparison of detection methods for bovine viral diarrhea virus in bovine abortions and neonatal death. | the objective of this study was to examine a monoclonal antibody-based immunohistochemical staining method for its efficacy in diagnosis of bovine virus diarrhea virus (bvdv)-induced abortion and neonatal calf death. this method was compared to viral isolation and immunofluorescence staining of frozen tissue sections. tissues from 105 cases, 53 fetuses and 52 neonates, were tested by the 3 methods. there were significant numbers of both false negatives and false positives with the immunofluoresc ... | 1995 | 8580161 |
| molecular biology of bovine viral diarrhea virus and its interactions with the host. | the contributions of pestivirus molecular biology research to our understanding of bovine viral diarrhea virus (bvdv) biology and disease have been remarkable. completion of nucleotide sequence information for genomes of ncp and cp-bvdv isolates was an important milestone. subsequent work on the protein map of bvdv and polyprotein processing pathways paved the way for the interpretation of many other virologic and immunologic studies. discovery of a correlation between genotype ii and virulence ... | 1995 | 8581855 |
| the clinical manifestations of bovine viral diarrhea infection. | bvdv infections may result in a wide range of clinical manifestations ranging from subclinical infections to a severe, highly fatal form referred to as md. in recent years, a better understanding of pathogenesis has been achieved that has allowed for a better understanding of the different clinical forms of bvdv infection. knowledge in this area continues to evolve. the clinical forms of bvdv infections are best understood by breaking them into categories that include infections in immunocompete ... | 1995 | 8581856 |
| the pathologies of bovine viral diarrhea virus infection. a window on the pathogenesis. | pathologic lesions caused by bovine viral diarrhea virus (bvdv) infections comprise a wide spectrum of type, degree, and, by implication, pathogenesis, including congenital defects, necroticerosive lesions in mucosal epithelia and skin, and reactive as well as degenerative changes in lymphoid tissues. at least some of the pathology may not be solely due to bvdv replication per se, but rather caused by a host response to the virus, particularly the production of pro-inflammatory cytokines. | 1995 | 8581857 |
| pathogenesis of intrauterine infections with bovine viral diarrhea virus. | bvdv shares with other pestiviruses the ability to cross the placenta of pregnant host animals. the effects of fetal infections are complex and depend on a number of factors, e.g., age of the zygote/embryo stage, no infection seems to occur. during the last one third of gestation the infection is terminated by the ontogeny of the fetal immune system. this leaves a window of susceptibility during early stages of fetal development allowing establishment of viral persistence and/or the development ... | 1995 | 8581858 |
| the pathogenesis of mucosal disease. | the pathogenesis of md is complex and remains somewhat obscure. clearly, the disease occurs in cattle persistently infected with noncytopathic bvdv. it also is clear that cytopathic bvdv is associated with md, and is the likely trigger of the cellular destruction that leads to clinical disease. whether the cellular destruction is attributable directly to the cytopathic virus, or occurs as the result of other mechanisms remains unclear. although immunotolerance is involved in md, it can be broken ... | 1995 | 8581859 |
| immunology of bovine viral diarrhea virus. | often persistent and primary postnatal infections with bvdv result in immunosuppression in cattle, thereby enhancing the vulnerability of the latter to secondary infections. the evidence for and nature of impaired immunity in these animals is reviewed. our knowledge of the extent and nature of protective immunity induced by natural bvdv infections and vaccines is still in its infancy. significant new information on the bovine immune response to bvdv antigens, however, has been identified in rece ... | 1995 | 8581860 |
| epidemiology of bovine viral diarrhea virus. | prevalence studies around the world show that bvdv is widespread in most cattle raising countries. there are significant differences, however, in prevalence between areas, probably the result of differences in cattle population structure and management practice. direct contact with pi animals is probably the most important method of transmission of infection; however, field studies have shown that some limited spread of infection also occurs in the absence of pi animals. this may be due to conta ... | 1995 | 8581861 |
| diagnosis of bovine viral diarrhea virus infections. | because of complex pathogenesis and insidious nature of bvdv infections, the laboratory diagnosis is an essential component of developing measures for the control and prevention of bvdv infections. the positive isolation of bvdv from animal submissions or from aborted fetuses should provide a strong indication for further epidemiologic investigations within the identified infected herds. in these situations, the ultimate goal should be the establishment of sound control and prevention methods by ... | 1995 | 8581862 |
| control of bovine viral diarrhea infection by use of vaccination. | vaccination with either inactivated or modified live virus vaccines is beneficial for control of bvd in cattle. the advantages and/or disadvantages of each type of vaccine often influence vaccine selection. the frequency of vaccination depends on the herd management system, regional prevalence of bvdv, and required duration of protection. vaccines for bvd likely will change in content as knowledge of bvdv increases and as new technologies are adapted for vaccine production. | 1995 | 8581866 |
| control of bovine viral diarrhea virus infection without vaccines. | successful control and eradication of bvdv infection presuppose sufficient knowledge of its epidemiology, particularly sources of infection and ways of transmission. furthermore, it is crucial to have tests that can be trusted to give the true infection of individual animals and indicate the infection status of herds. pi animals are considered to be the main source of infection. in preliminary experiments in denmark, it was found that eradication in herds could be based on the identification and ... | 1995 | 8581867 |
| isolation of bovine viral diarrhea virus-like pestiviruses from roe deer (capreolus capreolus). | cytopathogenic pestiviruses were isolated from two seronegative free-ranging roe deer (capreolus capreolus) from northern germany (schleswig-holstein): an adult female and a young buck collected on 6 december 1990 and 26 july 1991, respectively. the two isolates were identified by polymerase chain reaction as pestiviruses. however, they were negative when primers specific for bovine virus diarrhea virus or classical swine fever virus were used, indicating that the two isolates might belong to a ... | 1995 | 8583645 |
| bovine virus diarrhea and mucosal disease in free-ranging and captive deer (cervidae) in germany. | from 1990 until 1992, 355 blood samples of roe deer (capreolus capreolus) (n = 123), red deer (cervus elaphus) (n = 60), fallow deer (dama dama) (n = 87) and other cervid species (n = 85) from three different habitats (n = 180) and 11 wildlife parks or zoos (n = 175) in germany were tested for prevalence of pestivirus antibodies. seventeen samples were seropositive for bovine viral diarrhea virus (bvdv); only one animal had antibodies for border disease virus. microneutralization test titers ran ... | 1995 | 8583646 |
| diagnosis of naturally occurring bovine viral diarrhea virus infections in ruminants using monoclonal antibody-based immunohistochemistry. | formalin-fixed paraffin-embedded tissues from 50 spontaneous cases (39 bovine, nine ovine, two caprine) of bovine viral diarrhea virus (bvdv) infection diagnosed by virus isolation were retrospectively examined for bvdv antigen by immunohistochemistry using anti-bvdv gp-43 monoclonal antibody (mab 15c5). the cases were separated into enteric disease syndrome, respiratory disease syndrome, and abortion/weak calf syndrome based upon clinical disease. the purposes of the study were to 1) compare ro ... | 1995 | 8592795 |
| attempt to discriminate between bovine viral-diarrhoea virus strains using polymerase chain reaction. | the polymerase chain reaction (pcr) was applied to detect bovine viral-diarrhoea mucosal-disease virus (bvdv). by the use of properly prepared primers, cytopathogenic nadl, oregon c24v, nose, t-20 and ks86-1(+) strains, and non-cytopathogenic new york-1, no. 12, and ks86-1(-) strains could be detected. the pcr system was applied to field isolates of the viruses. all the viruses were detected by the pcr. four patterns of the pcr amplification were recognized, and it was possible to discriminate b ... | 1995 | 8592900 |
| variation in neuropathogenicity in sheep fetuses transplacentally infected with non-cytopathogenic and cytopathogenic biotypes of bovine-virus diarrhoea virus. | pregnant merino ewes were inoculated intravenously between days 63 and 65 of gestation with a non-cytopathogenic (ncp) bovine-virus diarrhoea-virus (bvdv) isolate (experiment a). the histomorphological findings and the distribution of viral antigen, as revealed by immunohistochemistry in brains of fetuses from experiment a, were compared with those seen in fetal brains from a previous study (experiment b), in which pregnant ewes had been intravenously infected between days 65 and 68 of gestation ... | 1995 | 8592912 |
| reverse transcription combined with polymerase chain reaction as a detection method for pestiviral infections. | an assay based on reverse transcription coupled with the polymerase chain reaction (rt-pcr) was used for the detection of hog cholera virus (hcv) and bovine virus diarrhoea virus (bvdv) in cell culture. in this study, a precipitate of the supernatants derived from cell cultures infected with hcv and bvdv was used in rt reactions, in place of extracted viral rna. both rt and pcr were performed using recombinant thermus thermophilus (rtth) dna polymerase. the specificity of the rt-pcr products was ... | 1995 | 8593411 |
| brain malformations in ovine fetuses associated with the cytopathogenic biotype of bovine viral-diarrhoea virus. | a total of six ewes were intravenously inoculated at between 65 and 68 days of gestation with the indiana strain of bovine viral diarrhoea virus (bvdv), containing both non-cytopathogenic (ncp) and cytopathogenic (cp) biotypes. eight transplacentally infected fetuses were sequentially removed from the infected ewes and were found to have inflammatory lesions and malformations of the brain. bvdv rna was isolated from formalin-fixed, paraffin-embedded brain tissue sections and detected by nested p ... | 1995 | 8594858 |
| immunodominant e2 (gp53) sequences of highly virulent bovine viral diarrhea group ii viruses indicate a close resemblance to a subgroup of border disease viruses. | the genes for the e2 envelope protein, which elicits virus-neutralizing antibodies, from members of the newly described group ii of bovine viral diarrhea viruses (bvdvs) were cloned and sequenced. these bvdvs included a thrombocytopenic strain from the united states, a fetal bovine serum contaminant, a strain from western canada, and two highly virulent strains, causing high mortality rates, from quebec. the nucleotide and amino acid sequences of these e2s had only a 60-65% homology with group i ... | 1996 | 8599222 |
| differentiation of classical swine fever virus (csfv) strains using monoclonal antibodies against structural glycoproteins. | two panels of monoclonal antibodies (mabs) against the classical swine fever virus (csfv) envelope glycoproteins e2 (12 mabs) and e0 (11 mabs) were established and tested by immunoperoxidase binding assay against 135 pestivirus strains and isolates. variability of the binding pattern was demonstrated for csfv and also for bovine viral diarrhea virus (bvdv) strains and isolates. the panels of mabs against e2 and e0 led to very different reactivity patterns. particular mabs against e2 reacted with ... | 1995 | 8604543 |
| ruminant pestiviruses. | the ruminant pestiviruses, bovine virus diarrhoea virus (bvdv) and border disease virus (bdv) are highly successful and important pathogens which infect ruminant species worldwide. although the serological relationships among ruminant pestiviruses require further clarification, there is growing evidence for two antigenic groups, one of which predominates in cattle and one in sheep. the success of pestiviruses stems from the ability of the non-cytopathic (ncp) biotype of the virus to cross the pl ... | 1995 | 8605577 |
| rapid and sensitive polymerase chain reaction based detection and typing of foot-and-mouth disease virus in clinical samples and cell culture isolates, combined with a simultaneous differentiation with other genomically and/or symptomatically related viruses. | reverse transcription followed by the polymerase chain reaction method (pcr) allowed the detection of foot-and-mouth disease virus (fmdv), regardless of the serotype. a primer set corresponding to highly conserved regions of the 2b sequence was selected. by combining in a single reaction tube specific primer pairs for fmdv, swine vesicular disease virus, (svdv), encephalomyocarditis virus (emcv) and bovine viral diarrhea virus (bvdv), all four viruses could be identified and differentiated in on ... | 1996 | 8634024 |
| cytokine regulation by virus infection: bovine viral diarrhea virus, a flavivirus, downregulates production of tumor necrosis factor alpha in macrophages in vitro. | bovine bone marrow-derived macrophages were infected in vitro with noncytopathic or cytopathic strains of bovine viral diarrhea virus. infection with both biotypes resulted in a decreased production of tumor necrosis factor alpha upon stimulation with heat-inactivated salmonella dublin or lipopolysaccharide. other macrophage functions were not downregulated, indicating that the observed effect was not due to a loss in macrophage viability. the downregulated production of tumor necrosis factor al ... | 1996 | 8642701 |
| processing in the pestivirus e2-ns2 region: identification of proteins p7 and e2p7. | the pestivirus genome encodes a single polyprotein which is subject to co- and posttranslational processing by cellular and viral proteases. the map positions of all virus-encoded proteins are known with the exception of a hypothetical peptide (p?) which interlinks the glycoprotein e2 and the nonstructural protein ns2-3 approximately between amino acid positions 1060 and 1130. expression studies with recombinant vaccinia viruses bearing a set of c-terminally truncated e2-p?-ns2-encoding sequence ... | 1996 | 8648755 |
| bovine virus diarrhoea virus in semen from acutely infected bulls. | the risk of spreading bovine virus diarrhoea virus (bvdv) from acutely infected animals to susceptible animals was investigated. ten bulls from a herd with no previous history of bvdv were used. the bulls were demonstrated free from bvdv and such antibodies. six of the bulls were inoculated intravenously with cytopathogenic virus, and 4 bulls were used as controls. semen samples were collected during a period of 66 days after inoculation. the samples were examined for bvdv, and spermatological p ... | 1996 | 8659345 |
| detection of bovine-virus-diarrhoea-virus antibodies in cattle with an enzyme-linked immunosorbent assay. | the serum-neutralization (sn) and the indirect-immunofluorescence (iif) assays have invariably been used for detecting antibodies against bovine virus diarrhoea virus (bvdv) in cattle sera. an enzyme-linked immunosorbent assay (elisa) was applied which has a sensitivity comparable with the sn and iif in detecting antibody to bvdv. a total of 472 bovine sera were assayed and a high prevalence of 79.2% was recorded. positive correlations between the elisa and the sn were found when certain sera we ... | 1995 | 8668322 |
| comparison of the prevalence and incidence of infection with bovine virus diarrhoea virus (bvdv) in denmark and michigan and association with possible risk factors. | based on 2 previous surveys on the occurrence of infection with bovine virus diarrhoea virus (bvdv) in danish and michigan dairy herds, the prevalence and incidence of the infection were compared. the presence of certain possible risk factors for the occurrence of infection in the 2 areas were summarized and it was investigated if any of these risk factors had significant effect on the presence of animals persistently infected (pi) with bvdv in the dairy herds. information on the cattle populati ... | 1995 | 8669379 |
| foetal infections with bovine viral diarrhoea virus in argentina. | the frequency of isolation of bovine viral diarrhoea virus (bvdv) from primary tissue cultures and organs from bovine foetuses was studied between 1992 and 1994. around 25% of primary tissue cultures were bvdv positive. primary testis cultures were inoculated with homogenates of spleen, kidney, lung and liver from 52 foetuses. cells were passaged twice and bvdv antigen investigated by indirect immunofluorescence. non-cytopathic bvdv was detected in at least one organ in 11/52 foetuses (21.2%): 6 ... | 1996 | 8680840 |
| [pcr: a look behind the scenes at bovine viral diarrhea virus]. | as indicated by their nucleotide sequences bovine viral diarrhea viruses (bvd-virus) are genetically quite heterogenous. despite differences in the nucleotide sequence in the ns3 region, we found that the derived amino acid sequence of all viral strains analyzed was identical and differed from that of classical swine fever viruses, thus allowing differentiation between bovine and porcine pestiviruses. remarkably, the bvd viral strains were isolated over a time period of some 40 years in europe, ... | 1996 | 8720729 |
| morphologic changes and immunohistochemical detection of viral antigen in ovaries from cattle persistently infected with bovine viral diarrhea virus. | to identify morphologic differences in ovaries from cows persistently infected with bovine viral diarrhea virus (bvdv) and determine ovarian cell types infected in these cows. | 1996 | 8725808 |
| concurrent bovine viral diarrhoea virus and salmonella typhimurium dt104 infection in a group of pregnant dairy heifers. | two days after being imported into the united kingdom one of a group of 30 pregnant dairy heifers showed clinical signs of bovine viral diarrhoea virus (bvdv) infection and subsequently died. before it died the heifer was bvdv antigen-positive and antibody-negative. the gross post mortem findings were suggestive of mucosal disease but in addition to noncytopathic bvd virus, salmonella typhimurium dt104 was cultured from tissues and gut contents. the other heifers were screened for s typhimurium ... | 1996 | 8736500 |
| distribution of virus and viral antigen in specific pathogen-free calves following inoculation with noncytopathic bovine viral diarrhea virus. | gross and microscopic lesions and distribution of virus were studied in specific pathogen-free calves (spf) 10 days post-inoculation (pi) with bovine viral diarrhea virus (bvdv). to investigate possible differences in tissue tropism between bcdv isolates, two clinically and antigenically different noncytopathic (ncp) isolates of bvdv were compared in the study. four calves were exposed to noncytopathic (ncp) bvdv 7937, and four to ncp-bvdv 126. two additional calves that were not exposed to viru ... | 1996 | 8740705 |
| six antigenic groups within the genus pestivirus as identified by cross neutralization assays. | antigenic differences between pestivirus isolates of ruminant and porcine origin were characterized by neutralization assays. first, six different clusters of pestiviruses were identified by clustering cross-neutralization results of 13 pestivirus strains tested against 23 sera. cluster i consisted of four strains of bovine viral diarrhoea virus (bvdv) of bovine origin and two bvdv isolates of porcine origin. cluster ii consisted of one sheep isolate and two porcine bdv isolates. cluster iii con ... | 1995 | 8748547 |
| cell death induced by cytopathic bovine viral diarrhoea virus is mediated by apoptosis. | cells infected with two closely related isolates of bovine viral diarrhoea virus (bvdv), one cytopathic (cp) and one non-cytopathic (ncp), were examined for signs of apoptosis. the results from labelling dna using terminal transferase and biotinylated dutp and by observing oligonucleosomal-sized dna fragmentation indicated that the cp strain of bvdv induced apoptosis in cell culture but the ncp strain did not. induction of apoptosis correlated with infected cells undergoing apoptosis rather than ... | 1996 | 8760414 |
| serological responses in calves to vaccines against bovine respiratory syncytial, infectious bovine rhinotracheitis, bovine viral diarrhoea and parainfluenza-3 viruses. | the istituto superiore di sanità (iss), the national veterinary services laboratory in italy, is in charge of assessing the quality, safety and efficacy of veterinary vaccines before and after licensing. to evaluate the relative potency of several vaccines against bovine respiratory syncytial virus (brsv), infectious bovine rhinotracheitis virus (ibrv), bovine viral diarrhoea virus (bvdv) and parainfluenza-3 virus (pi3v), the serological responses in vaccinated calves were studied. vaccination w ... | 1996 | 8785944 |
| demonstration and genotyping of pestivirus rna from mammalian cell lines. | we examined 20 cell lines of various animal origins for the presence of pestivirus contamination by the reverse transcription-polymerase chain reaction (rt-pcr), and found 15 (75%) cell lines were positive. the rt-pcr products of the 5' untranslated region (utr) of pestivirus genome were sequenced and subjected to genotyping. stem-loop structures at three variable regions in the 5' utr render genotyping of the contaminated pestiviruses. bovine cell lines tested were all contaminated with genotyp ... | 1995 | 8789057 |
| genetic identification of pestivirus strain frijters as a border disease virus from pigs. | a pig pestivirus isolate, the frijters strain, was characterized by using reverse transcription-pcr (rt-pcr), followed by rflp and direct sequencing of the amplicons. restriction endonuclease enzyme avai and bg/i digestion of 5' nc genomic region pcr products suggested that frijters strain belongs to the border disease viruses (bdv). this finding was confirmed by nucleotide sequencing of the amplified part of the 5-nc genomic region, which revealed 94% and 95% nucleotide similarity between the f ... | 1996 | 8795011 |