| detection of bovine viral diarrhea virus, using degenerate oligonucleotide primers and the polymerase chain reaction. | a technique for detection of bovine viral diarrhea virus (bvdv) from circulating blood leukocytes, using the polymerase chain reaction, is described. the published nucleotide sequences of 2 strains of bvdv and that of hog cholera virus were aligned and the information was used to design oligonucleotides coding for 2 regions of amino acid homology. the oligonucleotides were a mixed population including all possible codons for the conserved amino acids. these degenerate oligonucleotides were used ... | 1991 | 1656820 |
| monitoring bovine viral diarrhea virus vaccines for adventitious virus, using t1 ribonuclease viral rna oligonucleotide fingerprinting. | viral rna oligonucleotide fingerprinting was used to discriminate 3 cytopathic vaccine bovine viral diarrhea viruses (bvdv) grown in medium supplemented with serum contaminated with noncytopathic bvdv from the same 3 viruses grown in cell culture free of bvdv. oligonucleotide fingerprinting also effectively discriminated between reference singer bvdv, nadl bvdv, and new york-1 bvdv grown in bvdv-free noncontaminated or bvdv-contaminated cell cultures. oligonucleotide fingerprint mapping of viral ... | 1991 | 1656821 |
| specific sequence amplification of bovine virus diarrhea virus (bvdv) and hog cholera virus and sequencing of bvdv nucleic acid. | the pestiviruses are small enveloped rna viruses and are causative agents of economically important animal diseases in cattle, swine, sheep and goats worldwide. we used the polymerase chain reaction to amplify one common fragment of several different strains of both hog cholera virus and bovine virus diarrhea virus (bvdv). the fragment is located at the 5'-end of the genome immediately upstream of the open reading frame. this is a highly conserved region among the different published pestivirus ... | 1991 | 1659027 |
| bovine viral diarrhoea virus-specific bovine monoclonal antibody. | a bovine monoclonal antibody specific for bovine viral diarrhoea virus (bvdv) recognized all the reference strains of bvdv and over 90% of the field isolates tested. it neutralized the virus and precipitated a 56 k-58 k viral protein. | 1991 | 1662040 |
| protective effect of an iscom bovine virus diarrhoea virus (bvdv) vaccine against an experimental bvdv infection in vaccinated and non-vaccinated pregnant ewes. | fifteen pregnant ewes were vaccinated twice with an experimental immunostimulating complex (iscom) subunit vaccine designed to contain the envelope proteins of a danish cytopathic bovine virus diarrhoea virus (bvdv). the serological responses were measured in elisa and virus neutralization (vn) tests. all iscom-vaccinated ewes developed high vn antibody titres to bvdv in contrast to the 14 non-vaccinated ewes. both groups of ewes were challenged parenterally when 48-65 days pregnant with a swedi ... | 1991 | 1663302 |
| bovine viral diarrhea virus proteins: relatedness of p175 with p80 and p125 and evidence of glycoprotein processing. | three monoclonal antibodies, which recognized two nonoverlapping antigenic domains and were reactive to the bovine viral diarrhea virus (bvdv) p80 protein, were found to cross react with the p125 protein of both cytopathic and noncytopathic bvdvs and a molecular weight 175,000 bvdv protein (p175). results from limited proteolysis and chemical cleavage experiments confirmed the relatedness of these three proteins. in pulse-chase experiments it was apparent that p175 was a transient protein, as it ... | 1991 | 1663821 |
| calf from a persistently infected heifer born after embryo transfer with normal immunity to bvdv. | | 1991 | 1664160 |
| hybridization analysis of genomic variability among isolates of bovine viral diarrhoea virus using cdna probes. | genomic variability among 28 cytopathic and 37 non-cytopathic isolates of bvdv was evaluated using hybridization analysis. total rna, isolated from cell cultures infected with bvdv, was probed with each of three plasmids containing cdna derived from the cytopathic bvdv-nadl isolate. the three cdna plasmid probes represented about 40% of the bvdv-nadl genome. the probes originated from the 5' end of the viral genome, the region of the genome coding for the p80 polypeptide and the 3' end of the ge ... | 1991 | 1665207 |
| viral contamination of fetal bovine serum used for tissue culture: risks and concerns. | four viral contaminants have been routinely detected in unprocessed and commercial lots of fetal bovine serum: bacteriophage, infectious bovine rhinotracheitis, parainfluenza-3 and bovine viral diarrhea virus (bvdv). of those, bvdv is consistently present in a majority of commercial lots of fetal bovine serum. methods for bvdv detection and removal are reviewed. the tentative role of an unclassified pestivirus in microcephaly of infants has been reported. its significance remains uncertain. | 1991 | 1665460 |
| bovine viral diarrhea virus contamination of nutrient serum, cell cultures and viral vaccines. | bovine viral diarrhea virus (bvdv) infection is common in the bovine population. infection in utero leads to virus and antibody contamination of the fetal bovine serum used in cell cultures. these contaminants can interfere with diagnosis of viral infection. the high frequency of virus and antibody detection in individual animal or small pool samples suggests that any large pool of unscreened sera will be contaminated. infection of cell cultures with bvdv can lead to interference with the growth ... | 1991 | 1665461 |
| clinical, post mortem and virological findings after simultaneous inoculation of pigs with hog cholera and bovine viral diarrhoea virus. | the clinical course, post mortem lesions as well as virological and serological results after simultaneous intranasal inoculation of pigs with bovine viral diarrhoea virus (bvdv) and hog cholera virus (hcv) are described. five groups of four weaners received constant doses of bvdv strain osloss/2482 and tenfold decreasing doses of hcv strain alfort/187. doses of 1,000 and 100 tcid50 of hcv in groups a and b of pigs led to fever and severe clinical signs in all animals of two groups, whereas at h ... | 1991 | 1665632 |
| bovine coronavirus as the causative agent of winter dysentery: serological evidence. | sera from 9 dairy herds with epizootic enteritis (winter dysentery) were examined for antibodies to bovine coronavirus (bcv) and bovine virus diarrhoea virus (bvdv). cows in 8 of the 9 herds seroconverted to bcv alone, while the animals in the ninth herd, which showed severe symptoms of the disease, seroconverted both to bcv and bvdv. the bcv antibodies, which were present in high titres 1 year postinfection, were transferred to the offspring via the colostrum and were then detectable in sera of ... | 1991 | 1666489 |
| a monoclonal elisa for bovine viral diarrhoea pestivirus antigen detection in persistently infected cattle. | detection of cattle persistently infected with bovine viral diarrhoea virus (bvdv) is crucial to controlling mucosal disease. a sandwich enzyme-linked immunosorbent assay (elisa) using monoclonal antibodies raised against the 48-kda glycoprotein and the 120/80-kda protein was developed for detecting antigens in leucocytes of 3 persistently bvdv-infected calves. the test is simple, sensitive and rapid. moreover the same elisa was able to recognise belgian field isolates of bvdv. these results sho ... | 1991 | 1667787 |
| cytopathic and non-cytopathic biotypes of border disease virus induce polypeptides of different molecular weight with common antigenic determinants. | ten monoclonal antibodies have been raised against lysates of cells infected with cytopathic border disease virus (bdv). these antibodies all recognize non-cytopathic bdv and react with a number of different strains of bovine viral diarrhoea virus (bvdv). studies with radiolabelled cell lysates show that all the antibodies precipitate two polypeptides of apparent mr 80,000 and 130,000 from cells infected with cytopathic virus and a single polypeptide of apparent mr 120,000 from cells infected wi ... | 1990 | 1693167 |
| identification of conserved epitopes on a hog cholera virus protein. | eight monoclonal antibodies directed against the hog cholera virus (hcv) strain alfort/187 and displaying broad cross-reactivity with other hcv strains were characterized. an enzyme immunoassay on fixed monolayers of porcine or bovine cells infected with 14 different strains and isolates of hcv and 12 bovine viral diarrhea viruses (bvdv), respectively, showed that all antibodies reacted with hcv only. seven antibodies recognized all hcv tested, thus indicating that they were directed against con ... | 1990 | 1693844 |
| monoclonal antibodies to the p80/125 gp53 proteins of bovine viral diarrhea virus: their potential use as diagnostic reagents. | monoclonal antibodies reactive to the bovine viral diarrhea virus (bvdv) protein gp53 were produced and characterized. these antibodies and our panel of anti-p80/125 monoclonal antibodies were tested for their cross-reactivity with 11 different north american and european (danish) bvdv strains and isolates including viruses of both cytopathic and noncytopathic biotypes. the four anti-gp53 monoclonal antibodies were neutralizing for the homologous danish cytopathic isolate and cross-reacted with ... | 1990 | 1696159 |
| rapid detection of bovine viral diarrhea virus by polymerase chain reaction. | the polymerase chain reaction was used to detect genomic sequences of the positive-stranded rna of bovine viral diarrhea virus (bvdv), a member of the family togaviridae. using a set of 20-bp primers located within the conserved 3' region of the bvdv genome, we were able to consistently amplify a 205-bp target sequence from bvdv cdna. bvdv rnas from cell culture-propagated bvdv reference strains, diverse unrelated cytopathic and noncytopathic field isolates, and clinical serum samples were trans ... | 1991 | 1709950 |
| immunofluorescence studies of biotype-specific expression of bovine viral diarrhoea virus epitopes in infected cells. | the expression of biotype-specific epitopes in cells infected with cytopathic (cp) and non-cytopathic (ncp) bovine viral diarrhoea virus (bvdv) was analysed by immunofluorescence. four monoclonal antibodies (mabs) directed against different epitopes on the viral glycoprotein gp48 were used. with cells infected with cpbvdv strain nadl, the four mabs yielded a strong and granular cytoplasmic fluorescence. the same pattern was observed when cells were infected with ncpbvdv 7443 with two of the mabs ... | 1991 | 1714946 |
| primary bovine viral diarrhoea virus infection in calves following direct contact with a persistently viraemic calf. | six calves, aged 24 to 58 days and not previously exposed to bovine viral diarrhoea virus (bvdv), were infected with this agent by nose-to-nose contact with a persistently bvdv viraemic calf. the study was conducted in two trials, using 3 calves in each. all 6 calves showed a peak interferon level in serum at 4 days post infection (dpi), and they seroconverted to bvdv at 16-21 dpi. the calves in trial 1 had diarrhoea for 2 or 3 days between 2 and 6 dpi and one calf again from 9 to 11 dpi. during ... | 1991 | 1719713 |
| anti-idiotypic antibodies mimic bovine viral diarrhea virus antigen. | polyclonal rabbit anti-idiotypic antibodies (anti-ids) against two neutralizing murine monoclonal antibodies (mabs) specific to a bovine viral diarrhea virus (bvdv) glycoprotein, 53 kda, were produced, purified, and characterized. each anti-id inhibited the binding of its respective mab to bvdv antigen in a competitive elisa and blocked the immunoprecipitation of the 53 kda protein by the mab. the anti-ids also inhibited the virus-neutralizing activity of their homologous mabs. these results sug ... | 1991 | 1722928 |
| mass screening of cattle sera against 14 infectious disease agents, using an elisa system for monitoring health in livestock. | mass screening elisa methods were developed for testing cattle serum for antibodies against 14 common livestock diseases simultaneously. the absorbance values were transformed to a %elisa (spectrophotometric antibody end point) by a computer interfaced with a microplate reader. a histogram indicating a cutoff point and a report for the veterinarian also was generated. the computer program produced a print-out of the antibody profile for each animal tested, the antibody concentration against each ... | 1991 | 1767993 |
| production and characterization of monoclonal antibodies against excretory-secretory products of fasciola hepatica. | four monoclonal antibodies (mabs) (9.49, 24.27, 46.71 and 179.57) were produced against fasciola hepatica excretory-secretory products. isotype analysis revealed the antibodies to be igm, igg3, igg1, and igm. in immunoblot assays, the mabs recognized different antigenic polypeptides migrating between 29 and 180 kda. specificity of the mabs was evaluated by elisa against antigens of fascioloides magna, anoplocephala magna, stichorchis subtriquetrus, haemonchus contortus, sheep liver extract (sle) ... | 1991 | 1788930 |
| viral cytopathogenicity correlated with integration of ubiquitin-coding sequences. | the rna genomes of cytopathogenic bovine viral diarrhea virus (bvdv) isolates contain insertions highly homologous to cellular sequences. for two of them the insert was identified as ubiquitin coding sequence. the genome of bvdv osloss contains exactly one ubiquitin gene monomer. in the case of bvdv cp1 the cellular insertion comprises one complete ubiquitin gene and part of a second monomer. the host cell-derived element in the cp1 genome is embedded in a large duplication of about 2.4 kb of vi ... | 1991 | 1846490 |
| transmission of bovine virus diarrhoea virus by blood feeding flies. | three species of blood-feeding flies (stomoxys calcitrans, haematopota pluvialis and hydrotaea irritans) were fed for five minutes on a bullock persistently infected with bovine virus diarrhoea virus (bvdv) containing 10(4.5)tcid50 non-cytopathic bvdv/ml serum, then subsequently fed on bvdv-free seronegative animals maintained in isolation. virus was isolated from recipient animals between days 5 and 10 using h pluvialis, and up to 72 hours after transmission with s calcitrans; virus isolation w ... | 1991 | 1850184 |
| detection of bvd viruses using synthetic oligonucleotides. | this study examined synthetic oligonucleotide probes as potential diagnostic tools for bovine viral diarrhea virus (bvdv). six 20-base sequences from across the genome were selected by homology analysis of the published genomic sequences of the nadl and osloss isolates of bvdv. rna was extracted from 22 bvdv isolates propagated in bovine turbinate (bt) cells, blotted, and probed with 32p end-labeled oligonucleotides. the stringency conditions used were such that more than a single base mismatch ... | 1991 | 1850232 |
| detection of bovine viral diarrhea (bvd) virus using the polymerase chain reaction. | the approach of reverse transcription (rt) followed by the polymerase chain reaction (pcr) was used to amplify three different fragments of the bovine viral diarrhea virus (bvdv) genome. two sets of primers framed two different regions within the gene coding for protein p80, the third set of primers was selected to amplify cdna within the envelope glycoprotein (gp53) region. all three sequences could be detected in the homologous strain (nadl), whereas only some of the fragments could be amplifi ... | 1991 | 1850892 |
| border disease in sheep caused by transmission of virus from cattle persistently infected with bovine virus diarrhoea virus. | two outbreaks of border disease occurred on farms with sheep flocks and breeding cattle. the infection of the pregnant sheep was probably caused by transmission of virus from calves persistently infected with non-cytopathic bovine virus diarrhoea virus (bvdv) which were kept in close confinement with the ewes during mid-pregnancy. border disease was also induced experimentally in eight lambs by exposing their dams at 38 to 78 days of gestation to a heifer persistently infected with bvdv. both th ... | 1991 | 1851350 |
| defective function of leukocytes from cattle persistently infected with bovine viral diarrhea virus, and the influence of recombinant cytokines. | cattle persistently infected with bovine viral diarrhea (bvd) virus have decreased neutrophil and lymphocyte functions. we reevaluated these functions and further characterized the inhibition of persistent bvd virus infection in neutrophils, using sensitive kinetic assays. in addition, the influence of in vitro incubation of neutrophils with recombinant bovine interferon gamma (rboifn gamma) and in vitro incubation of lymphocytes with recombinant bovine interleukin-2 was evaluated. significant ( ... | 1991 | 1852143 |
| hog cholera virus: molecular composition of virions from a pestivirus. | virions from hog cholera virus (hcv), a member of the genus pestivirus, were analyzed by using specific antibodies. the nucleocapsid protein was found to be a 14-kda molecule (hcv p14). an equivalent protein could also be demonstrated for virions from another pestivirus, bovine viral diarrhea virus. the hcv envelope is composed of three glycoproteins, hcv gp44/48, gp33, and gp55. all three exist in the form of disulfide-linked dimers in virus-infected cells and in virions; hcv gp44/48 and gp55 e ... | 1991 | 1870198 |
| cryptosporidiosis in neonatal calves: 277 cases (1986-1987). | from january 1986 through december 1987, 277 cases of cryptosporidiosis in calves were diagnosed by the south dakota state university diagnostic laboratory. cryptosporidium sp was the only pathogen identified in 142 (51.3%) of the calves. concurrent infections with rotavirus, coronavirus, escherichia coli, salmonella sp, bovine viral diarrhea virus, or other pathogens were identified in the remaining 135 calves. after elimination of cases involving autolyzed specimens or calves with chronic diar ... | 1991 | 1874678 |
| [veterinary medicine and molecular biology: possibilities and limits of virus detection]. | in the last years molecular biology has gained more and more influence in veterinary medicine, e.g. in animal breeding. in addition, methods of molecular biology may open new areas in the diagnosis of viral diseases, because they are fast and very sensitive. the following article displays an overview of molecular biological techniques that are currently in use for virus detection. in addition, the limits of these methods are discussed. in particular, the polymerase chain reaction (pcr) is descri ... | 1991 | 1902003 |
| effect of infection by bovine viral diarrhea virus (bvdv) in vitro on interleukin-1 activity of bovine monocytes. | the effect of bovine viral diarrhea virus (bvdv) infection in vitro on the interleukin-1 (il-1) activity of bovine monocytes was studied. supernatants from bvdv-infected monocytes suppressed il-1-stimulated proliferation of mouse thymocytes and masked lipopolysaccharide-stimulated il-1 activity of bovine monocytes in the mouse comitogen thymocyte assay. suppression of mouse thymocyte proliferation was restored by the addition of il-1. il-1 inhibitory activity was induced both by the prototype va ... | 1991 | 1949588 |
| genetic comparison of ovine and bovine pestiviruses. | viral rna oligonucleotide fingerprinting was used to compare genetic relationship among pestiviruses originating from ovine or bovine host species. ovine pestiviruses, including reference border disease virus and 2 border disease isolates originating from natural pestivirus infections of sheep, appeared to have a more distant genetic relationship among themselves than with certain bovine pestiviruses. a closer genetic relatedness was evident between border disease virus and 3 noncytopathic bovin ... | 1990 | 1964772 |
| some immune responses in cattle exposed to mycobacterium paratuberculosis after injection with modified-live bovine viral diarrhea virus vaccine. | delayed-type hypersensitivity responses to mycobacterium paratuberculosis purified protein derivative (ppd) were decreased in cows experimentally exposed to m. paratuberculosis 7 days after exposure to a modified-live bovine viral diarrhea virus (ml-bvdv) vaccine. in vitro lymphocyte blastogenic responses to phytohemagglutinin were decreased in each of 3 cows 7 days after exposure to ml-bvdv vaccine. also, decreased lymphocyte blastogenic responses to m. paratuberculosis ppd were observed in cul ... | 1990 | 1965582 |
| prospective serology and analysis in diagnosis of dairy cow abortion. | a prospective serologic investigation was undertaken on 3 california dairies (herds 1, 3, and 4, as previously designated in a report on abortion surveillance) to determine if fetal loss was associated with infectious disease agents in cows. the diagnostic problem in these herds was typical of many dairies in that abortions were not discovered for several months and aborted fetuses were seldom recovered. blood from approximately 100 pregnant cows in each herd was sampled at monthly intervals, be ... | 1990 | 1965632 |
| diagnosis of bovine viral diarrhea virus infection using monoclonal antibodies. | the monoclonal antibody (mab) d89 against bovine viral diarrhea virus (bvdv) was used in conjunction with fluorescein-conjugated anti-mouse immunoglobulin in an indirect fluorescent antibody (ifa) procedure on frozen tissue sections and cell culture. during the 2-year study, bvdv was isolated from specimens submitted in 460 cases. the d89 mab detected all but 2 bvdv isolates, both cytopathic. in 316 of the cases in which bvd virus was detected by ifa, specimens were inoculated on bovine turbinat ... | 1990 | 1965635 |
| molecular biology of bovine virus diarrhoea virus. | our understanding of the molecular biology of bovine virus diarrhoea virus (bvdv) has greatly increased over the past several years. the development of monoclonal antibodies (mab's) has identified a key antigen of bvdv while at the same time providing evidence for considerable variation in this protein. mab's, particularly those directed against the p80 protein, can be developed for use in diagnostic tests while others may be useful in molecular epidemiological studies of bvdv. the successful cl ... | 1990 | 1966716 |
| ruminant pestivirus infection in pigs. | ruminant pestivirus infections of pigs have a worldwide distribution. the prevalence is varied and depends mainly on (i) contact with cattle, (ii) age of pigs and (iii) degree of homology of virus strains used for serology, with field strains of bovine virus diarrhoea virus (bvdv) infecting pigs. emphasis should be laid on sources of bvdv other than cattle, e.g. contaminated vaccines and fetal calf serum. the need for differentiation of pestiviruses (hog cholera, bovine virus diarrhoea and borde ... | 1990 | 1966720 |
| bovine virus diarrhoea virus: speculation and observations on current concepts. | this final chapter highlights the advances and some of the unanswered questions concerning bovine virus diarrhoea virus (bvdv) presented in this review by specialists from around the world. persistently viraemic cattle play an essential role in the dissemination of bvdv but it is suggested that acute infections with the virus are also important. the role of latency is considered but, as yet, there is no evidence that it plays a part in pathogenesis. it is well established that bvdv, border disea ... | 1990 | 1966724 |
| electron microscopy of bovine virus diarrhoea virus. | bovine virus diarrhoea virus (bvdv) has been (tentatively) identified by electron microscopy in purified virus preparations, in infected cell cultures and in tissues and cells from infected animals. these studies have revealed a spherical membrane-bound particle with a diameter of 40-60 nm. the membrane is smooth, bilaminar and surrounds a dense or semi-dense core of 20-25 nm. the core particle may be isometric or hexagonal. in studies of the morphogenesis of bvdv in infected cell cultures, it w ... | 1990 | 1966727 |
| immunological responses to bovine virus diarrhoea virus infections. | infection of normal calves with bovine virus diarrhoea virus (bvdv) is a transient self-limiting infection that can result in a period of immunosuppression. the virus appears to be able to replicate in all of the major lymphocyte sub-populations as well as in accessory cells. this may result in the leukopenia that is often a sequel of infection and affects b-cells as well as the t-cell sub-populations expressing either bocd4 or bocd8 antigens. b and t-cell responses are affected as a consequence ... | 1990 | 1966728 |
| development of pneumonia in desert bighorn sheep after exposure to a flock of exotic wild and domestic sheep. | from 1986 to 1989, 5 desert bighorn sheep (3 ovis canadensis mexicana and 2 o c nelsoni), ranging in age from 2 to 3 years, were exposed to a flock of exotic wild and domestic sheep to potentially achieve naturally acquired pneumonia. pasteurella multocida was isolated from nasal samples from 4 of 6 sheep randomly sampled from the flock. bighorn sheep were exposed individually and each exposure period was a trial. treatment before and after exposure varied and included combinations of alpha inte ... | 1991 | 2032914 |
| comparison of persistence of seven bovine viruses on bovine embryos following in vitro exposure. | the ability of seven cytopathic strains of bovine viruses to adhere to the zona pellucida of six-to-eight day-old bovine embryos were compared. embryos were exposed to virus by placing them either in virus suspensions or by culturing them on infected bovine turbinate cultures for 18-24 h. after exposure to bovine virus diarrhea virus (bvdv), infectious bovine rhinotracheitis virus (ibv), bluetongue virus (btv), pseudorabies virus (prv), vesicular stomatitis virus (vsv), parainfluenza 3 virus (pi ... | 1990 | 2107070 |
| clinical aspects of bovine virus diarrhoea virus infection. | bovine virus diarrhoea virus (bvdv) infection of cattle results in a wide range of clinical manifestations. this article reviews the clinical responses associated with bvdv and discusses these diseases in terms of acute infection in immunocompetent cattle, fetal infection, infection in cattle immunotolerant to and persistently infected with bvdv and finally mucosal disease. | 1990 | 2132152 |
| the pathogenesis of bovine virus diarrhoea virus infections. | bovine virus diarrhoea virus (bvdv) disease in cattle ranges from the transient acute infections, which may be inapparent or mild, to mucosal disease which is inevitably fatal. on occasions the acute infections can lead to clinical episodes of diarrhoea and agalactia but as these syndromes cannot be reproduced experimentally, the pathogenesis remains unclear. the immunosuppressive effect of acute bvdv infections can enhance the clinical disease of other pathogens and this may be an important par ... | 1990 | 2132154 |
| epidemiology of bovine virus diarrhoea virus. | a better understanding of the epidemiology and pathogenesis of bovine virus diarrhoea virus (bvdv) has emerged in recent years. fetal infections and in particular those resulting in birth of persistently infected calves are of central importance for the epidemiology of bvdv. a prevalence of persistently infected, viraemic animals of about 1% is found in denmark and elsewhere by examination of randomly collected blood samples. a recent field study shows that 53% of randomly selected herds in an a ... | 1990 | 2132155 |
| thrombocytopenia and hemorrhages in veal calves infected with bovine viral diarrhea virus. | the relationship between bovine viral diarrhea virus (bvdv) infection and thrombocytopenia was studied in 18 veal calves experimentally infected with bvdv. all calves were free of bvdv, and 13 calves were free of serum neutralizing antibodies to bvdv before virus inoculation. calves were inoculated at approximately 10 days of age, and platelet counts were monitored over a period of several weeks. ten additional calves housed in close proximity were kept as uninoculated controls. a profound decre ... | 1990 | 2154423 |
| attempts to characterize bovine viral diarrhea virus isolated from cattle after immunization with a contaminated vaccine. | bovine viral diarrhea virus (bvdv) was isolated from 28 animals with a history of immunization against respiratory disease with a vaccine contaminated with bvdv. the vaccine-derived parental virus strain and the 28 isolates were analyzed using 10 monoclonal antibodies (mabs) directed against different epitopes and antigenic domains on the major envelope glycoprotein of bvdv. none of the isolates displayed a reaction pattern identical with the parental virus. instead, seven different reaction pat ... | 1990 | 2155768 |
| experimental transmission of bovine viral diseases by insemination with contaminated semen or during embryo transfer. | three experimental approaches were used to study transmission of blue tongue (bt), infectious bovine rhinotracheitis (ibr) and bovine virus diarrhoea (bvd) viruses. these were insemination with contaminated semen, experimental infection of embryo donor cows, or transfer of embryos experimentally exposed to virus in vitro to normal recipients. parameters assessed included number and quality of embryos produced, virus detection (isolation and electron microscopy), serology and histopathology. all ... | 1990 | 2155769 |
| hepatitis c virus shares amino acid sequence similarity with pestiviruses and flaviviruses as well as members of two plant virus supergroups. | hepatitis c virus (hcv) is an important human pathogen that is associated with transfusion-related non-a, non-b hepatitis. recently, hcv cdna was cloned and the nucleotide sequence of approximately three-quarters of the virus genome was determined. a region of the predicted polyprotein sequence was found to share similarity with a nonstructural protein encoded by dengue virus, a member of the flavivirus family. we report here that hcv shares an even greater degree of protein sequence similarity ... | 1990 | 2156259 |
| effect of host cell on the in vitro characteristics expressed by two bovine viral diarrhea virus strains. | growth curves, immunofluorescence assays and radioimmunoprecipitation analysis of bovine viral diarrhea virus (bvdv)-specified polypeptides were used to determine the susceptibility of bovine endothelial cells (becs) to infection with strains of bvdv. one strain of the virus, ny1, normally non-cytopathic when grown in bovine turbinate cells (btus), did not parallel this type behavior in becs. virus replication kinetics, morphological changes in infected cells and resolution of viral polypeptides ... | 1990 | 2156373 |
| a study of some pathogenetic aspects of bovine viral diarrhea virus infection. | the cytopathic (cp) tvm-2 strain of bovine viral diarrhea virus (bvdv) induced in calves a severe disease, characterized by the clinical picture which is usually reported for the acute primary infection observed under natural conditions. in contrast, the calves inoculated with a different biotype of bvdv, the non-cytopathic (ncp) new york-1 strain, remained clinically normal with the only evidence of virus replication in these calves being the recovery of the virus from their pharyngeal swabbing ... | 1990 | 2157576 |
| antibodies to bovine parvovirus acquired by neonatal pigs through ingestion of virus and antibody in the diet. | the ability of pigs to respond immunologically to ingestion of bovine parvovirus (bpv) was tested by feeding 4 cesarean-derived, colostrum-deprived (cdcd) pigs a live virus-contaminated, liquid diet for the first 4 weeks of life. virus-neutralizing (vn) antibodies were detected in the serum of 2 of the 4 pigs when they were 4 weeks old. antibody titer remained at about the same level for several weeks, then decreased during the remainder of the 29-week interval of testing. the relative reactivit ... | 1990 | 2158254 |
| insemination of susceptible and preimmunized cattle with bovine viral diarrhoea virus infected semen. | six susceptible and six preimmunized heifers were inseminated with semen from a bull persistently infected with bovine viral diarrhoea virus (bvdv). they had poor rates of conception, but ultimately, all but one conceived. eleven, apparently normal, calves were born, none of which showed evidence of bvdv infection. | 1990 | 2158848 |
| an enzyme-linked immunosorbent assay (elisa) for antibodies to bovine viral diarrhea virus. | a single dilution enzyme-linked immunosorbent assay (elisa) was developed to detect antibodies to bovine viral diarrhea (bvd) virus in cattle sera. viral antigen (nadl strain) was grown in a pig kidney cell line (pk15), and after removal of nuclear debris, was purified by ultracentrifugation through a potassium tartrate cushion. antigen grown in embryonic bovine tracheal epithelial cells was also satisfactory. the test used a high salt buffer to minimize nonspecific reactivity, polyethylene glyc ... | 1990 | 2159672 |
| range of viral neutralizing activity and molecular specificity of antibodies induced in cattle by inactivated bovine viral diarrhea virus vaccines. | the range of neutralizing activity to bovine viral diarrhea (bvd) virus and viral protein specificity of antibodies induced by 3 inactivated vaccines were evaluated by use of samples of sera obtained from 13 cattle 14 days after vaccination. viral neutralizing antibodies wee detected in all cattle to each of 10 noncytopathic and 10 cytopathic isolates of bvd virus. a viral-induced polypeptide (53,000 to 56,000 daltons) was detected by radioimmunoprecipitation with serum from all vaccinates. othe ... | 1990 | 2159737 |
| in vitro interactions of cytokines and bovine viral diarrhea virus in phytohemagglutinin-stimulated bovine mononuclear cells. | bovine viral diarrhea (bvd) virus inhibited phytohemagglutinin (pha)-stimulated bovine peripheral blood mononuclear cell (pbmc) proliferation and bovine interleukin-2 (il-2) production. in the controls, the heat-inactivated bvd virus was not capable of suppressing the pha-stimulated pbmc proliferation. presence of exogenous cytokines, such as purified human il-2, recombinant bovine interleukin-1 (rbovil-1), recombinant bovine il-2, and recombinant human il-6 failed to reverse the bvd virus-induc ... | 1990 | 2161582 |
| intracellular virus-induced polypeptides of pestivirus border disease virus. | intracellular virus specific polypeptides of pestivirus, border disease virus (bdv) in bovine turbinate cells were analysed by radio-immunoprecipitation with specific antisera. eleven viral polypeptides with molecular weights of 220, 165, 118, 84, 66, 58, 55, 53, 45, 37 and 31 kda, respectively, were detected in infected cells. of these, the 165, 118, 84, 66, 58, 55, 53, 45 and 31 kda proteins were found to be glycosylated. comparative studies indicated that the polypeptides induced by bdv share ... | 1990 | 2161595 |
| in vitro production of antibodies to bovine virus diarrhoea virus by peripheral blood mononuclear cells from cattle immunized by infection. | a method for in vitro production of antibodies to bovine virus diarrhoea virus (bvdv) by peripheral blood mononuclear cells (pbmc) was developed. the pbmc were cultured in microtitre plates coated with detergent-solubilized bvdv and the supernatants were tested in an enzyme-linked immunosorbent assay which detects igg antibodies to bvdv. following incubation of pbmc with an optimal concentration of pokeweed mitogen for 5 days, antibodies to bvdv were detected in culture supernatants of pbmc from ... | 1990 | 2162096 |
| molecular cloning and nucleotide sequence of hog cholera virus strain brescia and mapping of the genomic region encoding envelope protein e1. | genomic rna of hog cholera virus (hcv) strain brescia was cloned and sequenced. the nucleotide sequence was deduced from overlapping cdna clones and comprises 12,283 nucleotides. we cloned the complete 3' end of the hcv genome, but could not unequivocally prove that the cdna sequence also completely covers hcv rna at the 5' end. the hcv genome contained one large open reading frame, which spans the viral plus strand rna and encodes an amino acid sequence of 3898 residues with a calculated molecu ... | 1990 | 2162104 |
| specific sequence amplification of bovine viral diarrhoea virus nucleic acid. | bovine viral diarrhoea virus (bvdv) causes infection of cattle worldwide and is a common contaminant of cell cultures in the laboratory. methods of diagnosis for bvdv are time-consuming and inconsistent. we describe the development of an in vitro test based on enzymatic dna amplification with thermus aquaticus dna polymerase of sequences of bvdv cdna reverse transcribed from viral rna. specific sequences were amplified from infected cell cultures and clinical material using laboratory and field ... | 1990 | 2162162 |
| viral protein production in homogeneous and mixed infections of cytopathic and noncytopathic bvd virus. | experiments were conducted to examine dual infection of cultured cells with cytopathic and noncytopathic bovine viral diarrhea virus (bvdv). cell monolayers infected with a noncytopathic bvdv isolate and subsequently superinfected with a cytopathic bvdv isolate were refractive to the cytopathic effects of the cytopathic bvdv isolate, as reported in the literature. immunofluorescence staining of superinfected cultures with monoclonal antibodies specific for the cytopathic or the noncytopathic vir ... | 1990 | 2162163 |
| detection of bovine viral diarrhea virus genome in leukocytes from persistently infected cattle by rna-cdna hybridization. | a bovine viral diarrhea virus (bvdv) cdna library was constructed. one cloned complementary dna sequence was used as a probe to detect bvdv rna by hybridization in infected cell cultures and in mononuclear leukocytes from persistently infected cattle by dot blot and in situ hybridization. the cdna probe hybridized with all cytopathic and noncytopathic bvdv isolates tested. the hybridization results were consistent with results obtained using conventional subculturing and immunofluorescent staini ... | 1990 | 2162729 |
| surveillance for persistent bovine viral diarrhea virus infection in four artificial insemination centers. | four large bovine artificial insemination centers implemented a program of surveillance of resident and newly acquired bulls for persistent bovine viral diarrhea virus infection. infection was identified in 12 of 1,538 bulls. several clinical abnormalities, including acute and chronic mucosal disease, were evident among the persistently infected bulls. semen produced by such bulls consistently contained bovine viral diarrhea virus, and such contamination was not always accompanied by diminished ... | 1990 | 2163996 |
| the coding region for the 54-kda protein of several pestiviruses lacks host insertions but reveals a "zinc finger-like" domain. | we sequenced cdnas, amplified by the polymerase chain reaction (pcr), which correspond to the carboxy-terminal portion of the 54-kda protein of various cytopathic (cp) or noncytopathic (ncp) pestiviral strains. except for the previously described insertions in two cp strains of the bovine viral diarrhea virus (bvdv), we did not find comparable insertions in this gene in eight pestiviral strains. the predicted amino acid sequences of this 54-kda protein portion contain a conserved cysteine-rich s ... | 1990 | 2164736 |
| a group level analysis of the associations between antibodies to seven putative pathogens and respiratory disease and weight gain in ontario feedlot calves. | the associations, at the group level, between serological titer to pasteurella haemolytica surface antigens (ph), pasteurella haemolytica cytotoxin (ph-cytox), infectious bovine rhinotracheitis virus (ibrv), bovine virus diarrhea virus (bvdv), parainfluenza-3 virus (piv3), respiratory syncytial virus (rsv), mycoplasma dispar (md), m. bovis (mb), and respiratory disease treatment rates, relapse rates, and 28 day weight gains were investigated in 14 groups of calves entering two feedlots during ye ... | 1990 | 2165846 |
| antigenic variations in bovine viral diarrhea viruses detected by monoclonal antibodies. | five murine monoclonal antibodies (mabs) against the nadl strain of bovine viral diarrhea (bvd) virus were developed, identified, and characterized. four of the mabs were directed against a 53-kilodalton (kda) viral protein, and one was specific to a 47-kda polypeptide. competitive radioimmunoassay showed that two mabs were specific to related epitopes of the 53-kda protein, and the other three mabs were each specific to a different epitope. the mabs were used to study heterogeneity among bvd vi ... | 1990 | 2168436 |
| characterization of a panel of monoclonal antibodies and their use in the study of the antigenic diversity of bovine viral diarrhea virus. | a panel of 40 monoclonal antibodies (mab) specific for bovine viral diarrhea virus (bvdv) was produced, and each mab was characterized and grouped according to its viral protein specificity, immunoglobulin subclass, virus-neutralizing activity, and immunoreactivity with a large collection of bvdv isolates. the mab were found to be specific for 1 of 3 sets of related viral-induced proteins found in cells infected with the singer strain of bvdv. group-1 mab were specific for the 80- and 118-kiloda ... | 1990 | 2168687 |
| experimental primary postnatal bovine viral diarrhea viral infections in six-month-old calves. | eight clinically healthy calves were inoculated intranasally, four with either noncytopathic or four with cytopathic bovine viral diarrhea virus, and were necropsied 5 or 12 days post-inoculation. the most frequent gross lesion associated with noncytopathic or cytopathic viral infection was proximal colonic mural edema. consistent microscopic findings were acute to subacute tracheitis, mild enterocolitis with edema, petechial hemorrhages of mesenteric lymph nodes with mild follicular lymphocytic ... | 1990 | 2169664 |
| elisa detection of bovine viral diarrhoea virus specific antibodies using recombinant antigen and monoclonal antibodies. | a panel of monoclonal antibodies was prepared by immunization of balb/c mice with moredun (bd) virus strains. these antibodies were characterized by immunofluorescence and seroneutralization against bd, bvd and hog cholera (hc) virus strains, and radioimmunoprecipitation of bvd-infected cells extracts. the mabs reacting with the majority of the pestivirus strains recognize the 80 kda antigen of the bvd cytophathic strains. the 80 kda antigen of the bvd/osloss virus strain has been cloned and exp ... | 1990 | 2169672 |
| immunohistological detection of bovine viral diarrhoea virus antigen in the central nervous system of persistently infected cattle using monoclonal antibodies. | in a total of 25 cattle persistently infected with bovine viral diarrhoea virus (bvdv) the distribution of viral antigens in the central nervous system was studied. using a panel of monoclonal antibodies (anti pestivirus c16; anti cytophathic bvdv c38; anti cytopathic and non-cytopathic bvdv c42; anti gp53 bvdv ca-1 and ca-3) and the indirect immunoperoxidase technique, bvdv antigen was located exclusively in neurons. predilection sites for viral persistence were cerebral cortex and hippocampus. ... | 1990 | 2169673 |
| pathogenesis of mucosal disease and molecular aspects of bovine virus diarrhoea virus. | studies carried out over three decades, on the pathogenesis and epidemiology of bovine virus diarrhoea virus (bvdv), have provided the basis for our understanding of the aetiology of mucosal disease. experimental reproduction of the disease has demonstrated the mechanism of sequential infection and the role of the two virus biotypes. the need for "homogeneity" between the biotypes, causing mucosal disease, has demonstrated the precision of immunotolerance. the origin of the cytopathogenic biotyp ... | 1990 | 2169681 |
| investigation of bovine viral diarrhea virus infections in a range beef cattle herd. | bovine viral diarrhea virus (bvdv) infections resulting in clinical disease developed in calves, despite vaccination of dams and high maternal bvdv antibody titers in calves. eight persistently infected (pi) calves born to immunocompetent dams were identified in the herd. neutralizing bvdv antibody titers of pi calves had decreased greatly by the time the calves were 1 to 2 months old. antibody titers of pi calves decreased more rapidly than antibody titers of calves that were not pi. reduced an ... | 1990 | 2170313 |
| comparative pathogenicity of selected bovine viral diarrhea virus isolates in gnotobiotic lambs. | the infectivity and pathogenicity of selected bovine viral diarrhea virus (bvdv) isolates were determined in gnotobiotic, colostrum-deprived neonatal lambs. five-day-old cesarean-derived gnotobiotic lambs were exposed to 1 of 10 bvdv isolates via aerosol suspension. these isolates were from tissues or secretions of calves or lambs affected with respiratory tract disease, weak neonatal calves, aborted bovine fetuses, or reference singer or draper bvdv. the pathogenicity of each isolate, relative ... | 1990 | 2173447 |
| frequency of association of noncytopathic bovine viral diarrhea virus with bovine neutrophils and mononuclear leukocytes before and after treatment with trypsin. | enriched populations of neutrophils and mononuclear leukocytes from 9 cattle persistently infected with noncytopathic bovine viral diarrhea virus were analyzed for frequency of association with virus, using flow cytometric procedures. trypsinization of neutrophils decreased the frequency of viral association from 0.82% to 0.49%. similar treatment of mononuclear leukocytes decreased the frequency of viral association from 5.53% to 4.81%. results of immunocytochemical procedures to locate viral an ... | 1990 | 2173452 |
| flow cytometric detection of bovine viral diarrhea virus in peripheral blood leukocytes of persistently infected cattle. | flow cytometry was investigated for detection of bovine viral diarrhea virus (bvdv) in peripheral blood mononuclear leukocytes of persistently infected cattle. the mononuclear leukocytes were purified by sedimentation in a gradient of ficoll-paque, fixed, permeabilized, and then labelled by indirect immunofluorescence using biotinylated immunoglobulins from a porcine antiserum to bvdv. flow cytometric analysis of blood samples obtained from persistently infected cattle revealed virus in 3.0-21.0 ... | 1990 | 2174298 |
| experimental pestivirus infections in newborn goat kids. | two experiments were carried out in which 37 healthy newborn goat kids were inoculated with a non-cytopathic ovine (bdv) or a cytopathic bovine pestivirus (bvdv) by intramuscular or intracerebral injection. no kids showed signs of disease or gross lesions which could be attributed to these viruses, but inoculated kids had lower mean growth rates than the controls. significant histological changes in the cns of 14 kids were restricted largely to the white matter and consisted mainly of hypercellu ... | 1990 | 2175318 |
| detection of bovine viral diarrhea virus in serum from cattle by dot blot hybridization assay. | a dot blot hybridization assay was developed for use as a rapid screening test to detect bovine viral diarrhea virus (bvdv) in serum from infected cattle. a 1.1. kilobase cdna, prepared from the bvdv genome, was molecularly cloned and used in this study. insert cdna was removed from the puc9 plasmid vector by pst-i restriction endonuclease digestion and purified from plasmid dna by agarose electrophoresis and electroelution. the hybridization probe was prepared by nick translation in the presenc ... | 1990 | 2175527 |
| antigenic comparisons of hog cholera virus isolates from europe, america and asia using monoclonal antibodies. | nineteen monoclonal antibodies (mabs) with specificity for hog cholera virus (hcv) were prepared. they were used in an immune binding (peroxidase linked) assay to determine the reaction patterns of hcv isolates from europe, brazil, usa, japan and malaysia, as well as laboratory reference strains of the virus. a further panel of 17 mabs raised against bovine virus diarrhoea virus (bvdv) was included in the study, together with 5 mabs raised against a non-hcv pestivirus of porcine origin. all the ... | 1990 | 2178905 |
| a new approach for the diagnosis of hog cholera. | pestiviruses were isolated from seven cases of suspect hog cholera. using peroxidase conjugates of monoclonal antibodies (mabs) six isolates were identified as hog cholera viruses (hcv), while one isolate was of ruminant origin, possibly bovine viral diarrhea virus. in parallel attempts were made to develop an elisa for the detection of hcv-specific antibodies in pig sera. the mab hctc26 coated to polystyrol plates efficiently captured the major viral glycoprotein gp53 from crude antigen suspens ... | 1990 | 2178908 |
| attaching and effacing escherichia coli infection as a cause of diarrhea in young calves. | a form of enteric escherichia coli infection was identified in 60 calves from 59 farming operations. the e coli responsible for these infections principally colonized the colon, inducing a distinctive lesion described as attaching and effacing. hemorrhagic enterocolitis or blood in the feces was observed on 40% of the farms. of affected calves, 86.6% were dairy calves (average age, 11.8 days). forty-four calves were infected concurrently with other enteropathogens (cryptosporidia, rotavirus, cor ... | 1990 | 2179181 |
| [epidemiologic studies of the detection of viral infection agents in calf losses in the weser-ems region]. | in 961 calves up to an age of 6 months which were sent to the animal health center in oldenburg between march 1987 and march 1990 for necropsy the results of determination of different viruses were calculated: bvd-, rota-, corona-, parainfluenza-3- (pi-3)-, bovine herpes-1 (bhv-1)- and bovine respiratory syncytial virus (brsv). in 122 and 104 randomly collected health calves of 22 farms antibodies against brsv and bovine adeno virus-types 5, 7 and 8 were determined. 50.1% of the necropsied calve ... | 1990 | 2245783 |
| bovine viral diarrhea virus-induced cerebellar disease in a calf. | bovine viral diarrhea virus (bvdv) was isolated from buffy coat cells of a 10-day-old calf with signs of cerebellar disease--ataxia, hypermetria, and intention head tremor. the tentative diagnosis was bvdv-induced cerebellar hypoplasia. at necropsy, gross lesions were not identified. histologic findings suggested bvdv-induced diffuse hypomyelination throughout the cns, as reported in the united kingdom and the netherlands. | 1990 | 2276963 |
| pestivirus glycoprotein which induces neutralizing antibodies forms part of a disulfide-linked heterodimer. | neutralizing monoclonal antibodies directed against hog cholera virus (hcv) precipitated two hcv-encoded glycoproteins, hcv gp55 and hcv gp33. immunoassay with bacterial fusion proteins and western immunoblotting with extracts from infected cells revealed that the antibodies recognized only hcv gp55. coprecipitation of hcv gp33 was shown to be due to intermolecular disulfide bridges. one of the antibodies also reacted with the major glycoprotein of another pestivirus, bovine viral diarrhea virus ... | 1990 | 2370675 |
| molecular cloning of bovine viral diarrhea viral sequences. | bovine viral diarrhea virus (bvdv) genomic rna was identified as a 12.5-kb single-stranded rna molecule in both infected bovine embryonic kidney cells (bek-1) and partially purified virions. bvd virion rna was partially purified and used as a template for cdna synthesis. bvdv-specific cdna sequences were molecularly cloned and shown to hybridize to infected cell rna but not to uninfected cell rna or dna. a single rna species of 12.5 kb, representing the viral rna genome, was detected in infected ... | 1985 | 2419063 |
| production of monoclonal antibodies against swine fever virus and their use in laboratory diagnosis. | thirteen hybridoma cell lines which secrete monoclonal antibodies (mcas) against swine fever virus (sfv) strain brescia were produced. the hybrid cells resulted from fusion of p3x63-ag8.653 myeloma cells with splenocytes of balb/c mice which had been immunized with purified sfv. screening of supernatant fluids was performed by an indirect enzyme-linked immunosorbent assay (elisa) and an immunoperoxidase monolayer assay (ipma). the ipma, and an immunoperoxidase test (ipt) performed on cryostat se ... | 1986 | 2428160 |
| typing of cytopathic and noncytopathic bovine viral diarrhea virus reference and canadian field strains using a neutralizing monoclonal antibody. | cytopathic and noncytopathic reference strains as well as canadian field isolates of bovine viral diarrhea virus were analyzed by neutralization and immunofluorescence tests using a bovine viral diarrhea virus-specific neutralizing monoclonal antibody. results on reference strains indicated three major antigenic groups: i) nadl-like, ii) new york 1-like and iii) oregon c24v-like. field isolates could be segregated into groups i and ii and none could be typed into the group iii. it appears that m ... | 1988 | 2450629 |
| bovine viral diarrhea virus proteins: heterogeneity of cytopathogenic and non-cytopathogenic strains and evidence of a 53k glycoprotein neutralization epitope. | intracellular virus-induced polypeptides from 3 cytopathogenic and 2 non-cytopathogenic bovine viral diarrhea (bvd) virus reference strains were analyzed by radioimmunoprecipitation and polyacrylamide gel electrophoresis, using a specific bovine multivalent antiserum and a neutralizing bvd-virus monoclonal antibody. electrophoretic patterns of major proteins demonstrate extensive variation between strains. most notably, a major 80,000 (80k) polypeptide was present in all cytopathogenic strains b ... | 1988 | 2454527 |
| monoclonal antibody analyses of cytopathic and noncytopathic viruses from fatal bovine viral diarrhea virus infections. | a panel of monoclonal antibodies that recognize the two major glycoproteins of bovine viral diarrhea virus (bdv) was used to evaluate the antigenic relationship between cytopathic (cp) and noncytopathic (ncp) viruses isolated from cattle dead or dying from fatal bdv infections. various unrelated bdv isolates were initially screened by indirect immunofluorescence with monoclonal antibodies directed against the 56- to 58- and 48-kilodalton glycoproteins of the virus. a wide spectrum of reactivity ... | 1988 | 2455820 |
| a rapid, quantitative assay for titration of bovine virus diarrhoea-mucosal disease virus. | an end point dilution microtitration assay is described that can be used for the titration of both cytopathic and non-cytopathic isolates of bovine virus diarrhoea-mucosal disease virus. indirect immunofluorescence is used to detect infected mdbk cells in the wells of terasaki plates. the virus titre is derived from the number of uninfected wells, using the poisson distribution. the assay is simple, fast and economical. titres of cytopathic virus determined by the microtitration assay and standa ... | 1988 | 2466364 |
| detection and elimination of carrier animals in a dairy herd persistently infected with bovine viral diarrhea virus. | | 1989 | 2488357 |
| viral antigen distribution in the central nervous system of cattle persistently infected with bovine viral diarrhea virus. | distribution of viral antigens in the central nervous system of 25 cattle with a persistent bovine viral diarrhea virus (bvdv) infection was studied. using a polyclonal antiserum produced in pigs and the direct immunofluorescence and immunoperoxidase technique, bvdv antigen was located exclusively in neurons. predilection sites for viral persistence were cerebral cortex and hippocampus; in other areas of brain and spinal cord, viral antigens were in single neurons or small groups of neurons. the ... | 1989 | 2536511 |
| evaluation of the quality and virological status of semen from bulls acutely infected with bvdv. | | 1989 | 2537554 |
| serological comparison of cytopathogenic and non-cytopathogenic bovine viral diarrhea-mucosal disease viruses isolated from cattle with mucosal disease. | ten cattle that died with mucosal disease were examined for bovine viral diarrhea-mucosal disease (bvd-md) viruses. both cytopathogenic (cp) and non-cytopathogenic (ncp) bvd-md viruses were isolated concomitantly from 9 of them, and only a cp virus was recovered from the other. then each pair of cp and ncp viruses was compared serologically by a serum neutralization test. each pair of cp and ncp viruses from the same cattle was found to be serologically indistinguishable, although a minor antige ... | 1989 | 2538669 |
| a neutrophil-derived antiviral protein: induction requirements and biological properties. | polymorphonuclear neutrophilic granulocytes (pmn) have been implicated as playing a role in antiviral defense. in addition to having phagocytic and cytotoxic activities, pmn may produce an antiviral substance with interferon (ifn)-like activity. the product, for which the name polyferon (pf) has been coined, is produced upon direct encounter of pmn with bovine herpesvirus 1 (bhv-1)-infected bovine cells or membranes thereof. exposure to purified virus only does not induce pf. the intimate intera ... | 1989 | 2539494 |
| application of peroxidase labelled antibody assays for detection of porcine igg antibodies to hog cholera and bovine viral diarrhea viruses. | rapid, sensitive peroxidase labelled antibody (pla) assays using microtiter systems, were developed for detection of hog cholera virus (hcv) and cross-reacting bovine viral diarrhea virus (bvdv) antibodies in pig sera. hcv-infected pig kidney cell line (pk 15) prepared in microtiter plates were fixed and used in pla assays. after inoculation with test serum, bound antibodies (hcv/bvdv) were reacted with either horseradish peroxidase (hrp) conjugated anti-porcine immunoglobulin (h & l) or biotiny ... | 1989 | 2541152 |
| protection against respiratory infection with bovine virus diarrhoea virus by passively acquired antibody. | susceptibility to infection with bovine virus diarrhoea virus (bvdv) was compared for calves with varying amounts of specific antibody in their sera passively acquired from the ingestion of colostrum. challenge consisted of intranasal exposure to a strain of bvdv isolated from an outbreak of respiratory disease. resistance to infection, as judged by nasopharyngeal shedding of virus, was directly related to the titre of neutralizing antibodies in sera. besides protecting against infection of the ... | 1989 | 2541531 |
| efficacy of viral components of a nonabortigenic combination vaccine for prevention of respiratory and reproductive system diseases in cattle. | efficacy and safety of components of an im-administered vaccine for prevention of infectious bovine rhinotracheitis virus (ibrv), parainfluenza type-3 (pi-3) virus, bovine viral diarrhea virus (bvdv), and respiratory syncytial virus (rsv) infections and campylobacteriosis and leptospirosis were evaluated in cattle, including calves and pregnant cows. challenge of immunity tests were conducted in calves for ibrv, pi-3 virus, or bvdv vaccinal components. all inoculated calves developed serum-neutr ... | 1989 | 2542202 |
| experimental infection of cattle in early pregnancy with a cytopathic strain of bovine virus diarrhoea virus. | nine pregnant heifers, in early gestation (63 to 107 days), were infected intranasally or in utero with cytopathic bovine virus diarrhoea virus (bvdv) and each dam seroconverted. all nine calves developed to full term; four were stillborn, of which one had seroconverted but virus was not recovered from their tissues. one of the five liveborn calves appeared to have seroconverted in utero to an adventitious bvdv infection in late pregnancy but the remaining four were not viraemic and showed a nor ... | 1989 | 2544969 |
| demonstration of bovine virus diarrhoea virus antigen in formalin fixed, paraffin embedded tissue using a streptavidin/biotin technique. | the detection of bovine virus diarrhoea virus (bvdv) antigen in sections from formalin fixed, paraffin embedded tissue is described. pre-digestion of the sections with 0.02 per cent protease xiv for 18 hours at 4 degrees c is necessary to unmask formalin fixed antigen. a hyperimmune antiserum prepared in a pig, using a combination of bvdv and hog cholera virus inoculations, linked to a biotinylated anti-pig/streptavidin peroxidase detection system demonstrated antigen in a wide range of tissues ... | 1989 | 2544973 |