| molecular cloning of complementary dna from a pneumopathic strain of bovine viral diarrhea virus and its diagnostic application. | a pneumopathic strain of bovine viral diarrhea virus was grown in cell culture and purified. genomic ribonucleic acid was extracted, polyadenylated at the 3' end, and copied into complementary dna after oligo-dt priming. complementary dna was male double stranded and cloned into the puc9 plasmid. approximately 200 complementary dna clones varying in length from 0.5 to 2.5 kilobases were obtained. hybridization assays indicated that the sequences isolated were specific for bovine viral diarrhea v ... | 1988 | 2848623 |
| [epizootiology of herpesvirus infections in wild ruminants. ii. infectious bovine mammillitis and malignant catarrhal fever viruses and other viruses isolated from ruminants]. | | 1988 | 2849174 |
| characterization of a nonstructural phosphoprotein of two orbiviruses. | a phosphorylated nonstructural protein, ns2, was detected in bluetongue and african horsesickness virus (btv and ahsv) infected-radiolabeled-cell lysates by electrophoresis on sds-polyacrylamide gels (sds-page). the ns2 proteins of both viruses have similar migration on one-dimensional (1d) 10% sds-page. examination of infected cell lysates on two-dimensional (2d) gels (isoelectric focusing followed by sds-page) separated two phosphorylated isoelectric forms of btv ns2 and four phosphorylated fo ... | 1988 | 2849253 |
| nucleotide and deduced amino acid sequences of the non-structural protein, ns1, of australian and south african bluetongue virus serotype 1. | the sequence of the sense strand of rna segment 5 of both australian and south african bluetongue virus (btv) serotype 1 has been determined and found to be 1771 and 1773 nucleotides in length, respectively. both coding sequences of 1656 nucleotides were flanked by a 5' non-coding sequence of 34 nucleotides and 3' non-coding regions of 78 and 80 nucleotides, respectively. the methionine codons at residues 35-37 were assumed to initiate the synthesis of 64.6 or 64.415 kda proteins which had calcu ... | 1988 | 2849255 |
| evidence for genetic relationship between rna and dna viruses from the sequence homology of a putative polymerase gene of bluetongue virus with that of vaccinia virus: conservation of rna polymerase genes from diverse species. | the nucleotide sequence of segment 1 of the double stranded rna genome of bluetongue virus serotype 10 (btv-10), encoding the largest viral core protein, vp1, has been determined. linear sequence analysis of the predicted amino acid sequence of the 149-k da protein, a putative component of the viral rna-directed rna polymerase, revealed extensive homology with the vaccinia virus 147k da dna-directed rna polymerase subunit. similar homologies were detected between the vp1 polypeptide and the beta ... | 1988 | 2850542 |
| comparison of dot-blot and northern blot hybridizations in the determination of genetic relatedness of united states bluetongue virus serotypes. | dot-blot and northern blot hybridization methods to determine the genetic relatedness of united states bluetongue virus serotypes 2, 10, 11, 13, and 17 were compared. both plasmid and insert dna probes from cloned btv-17 dsrna segments 2, 5, 6, and 8 were hybridized to dsrna from the btv serotypes and epizootic hemorrhagic disease virus (ehdv). stringencies of hybridization were kept identical, and experiments differed only in the method in which dsrna was applied to the membranes (dot-blot or n ... | 1988 | 2851605 |
| comparison of virologic and serologic responses of lambs and calves infected with bluetongue virus serotype 10. | four lambs and 3 calves, seronegative to bluetongue virus (btv), were inoculated intravenously with a highly plaque-purified strain of btv serotype 10. a single calf and lamb served as controls and were inoculated with uninfected cell culture lysate. all btv-inoculated lambs exhibited mild clinical manifestations of bluetongue, whereas infected calves were asymptomatic. viremia persisted in btv-infected lambs for 35-42 days, and for 42-56 days in btv-infected calves. neutralizing antibodies were ... | 1988 | 2852871 |
| susceptibilities of 14 cell lines to bluetongue virus infection. | the effect of bluetongue virus (btv) infection was investigated in 14 cell lines. the cell lines included the following vertebrate cells: baby hamster kidney, african green monkey kidney (vero), rabbit kidney, bovine kidney, canine kidney, bovine turbinate, bovine endothelium (cpae), bighorn sheep tongue, equine dermis, gekko lung, rainbow trout gonad, and mouse fibroblast (l929); they also included the following invertebrate lines: mosquito and biting midge. comparisons between the cell lines w ... | 1988 | 2853175 |
| experimentally induced bluetongue virus infection in white-tailed deer: coagulation, clinical pathologic, and gross pathologic changes. | ten yearling white-tailed deer (odocoileus virginianus) were inoculated with bluetongue virus serotype 17. two yearling white-tailed deer were inoculated with sonicated heparinized noninfected blood and served as controls. clinical signs of bluetongue virus infection included increased rectal temperature, erythema, facial edema, coronitis, and stomatitis. by postinoculation day (pid) 8, excessive bleeding and hematoma formation at venipuncture sites, dehydration, and diarrhea developed. at necro ... | 1988 | 2854709 |
| experimentally induced bluetongue virus infection in white-tailed deer: ultrastructural findings. | white-tailed deer (odocoileus virginianus) were inoculated with bluetongue virus serotype 17 and sequentially euthanatized during infection. ultrastructural changes in the microvasculature of tongue, buccal mucosa, heart, and pulmonary artery, platelets, and bone marrow were evaluated. bluetongue virus was found in endothelial cells of the microvasculature by postinoculation day 4. viral replication was associated with the development of viral matrices, viral-associated macrotubules, and aggrega ... | 1988 | 2854710 |
| group-specific and type-specific gel diffusion precipitin tests for bluetongue virus serotype 20 and related viruses. | using antigens prepared from cell cultures infected by bluetongue (blu) virus type 20 (blu-20), and sera from cattle which had recovered from experimental infection by that virus, two distinct precipitin reactions were demonstrated by immunodiffusion. two distinct gel diffusion precipitin tests were developed based on these reactions. the antigen of one was common to blu-20 and two other australian blu isolates, csiro 154 (blu-21) and csiro 156 (blu-1). it was therefore concluded to be a group-s ... | 1988 | 2856013 |
| the occurrence of antibody to bluetongue virus in new south wales. i. statewide surveys of cattle and sheep. | two state-wide surveys were carried out in 1978 to detect bluetongue (blu) virus antibody in cattle and sheep sera in new south wales (nsw). the first survey showed that blu group antibody in cattle 18-24 months old was confined to the coastal regions (east of the great dividing range) and the hunter valley. however, in the second survey, of cattle more than 5 years old, reactors were much more widely distributed over the north-eastern third of the state and into the western division with preval ... | 1988 | 2856014 |
| the occurrence of antibody to bluetongue virus in new south wales. ii. coastal region and age distribution surveys. | three surveys of cattle for bluetongue (blu) antibody were conducted over the years 1978-1980 in coastal areas of new south wales. in each survey the samples were identified by age. the prevalence of blu-group antibody, demonstrated in a gel diffusion precipitin test, was highest in the north and decreased progressively to the south. antibody prevalence increased with age. however, according to variations in prevalence by age and region, it was concluded that the activity of relevant viruses was ... | 1988 | 2856015 |
| bluetongue and related viruses in new south wales: isolations from, and serological tests on samples from sentinel cattle. | sentinel cattle at a number of localities in northern and central coastal new south wales were sampled over the summer and autumn seasons of the years 1979, 1980 and 1981. a total of 118 orbiviruses were isolated; 99 were of the palyam group, 15 were of the epizootic haemorrhagic disease (ehd) of deer group, and 4 of the bluetongue group. the palyam group viruses were identified by serotype as 68 bunyip creek, 23 csiro village, 7 d'aguilar and one was not typed. the ehd viruses were identified a ... | 1988 | 2856016 |
| current knowledge on the biochemistry and immunology of bluetongue. | | 1985 | 2856167 |
| application of molecular techniques to the diagnosis of bluetongue virus infection. | | 1987 | 2856222 |
| induction of salivation in biting midges and mosquitoes, and demonstration of virus in the saliva of infected insects. | culicoides biting midges and aedes aegypti (linnaeus) mosquitoes were induced to salivate by the topical application of pilocarpine, neostigmine, malathion and dimethoate; of these, malathion was the most effective. drops of saliva produced by virus-infected midges and mosquitoes were shown to contain virus. the method could be used to demonstrate transmission in insects infected with a variety of pathogens. | 1987 | 2856508 |
| possible windborne spread to western turkey of bluetongue virus in 1977 and of akabane virus in 1979. | an outbreak of bluetongue in sheep started in the menderes valley, aydin province, western turkey, in october 1977. the severity of the disease indicated that it had not been there before but had been introduced into the area. analysis showed that, while it was possible for the virus to have been brought into the area by movement of infected animals, there was also a period of south-easterly winds which could have carried infected midges from cyprus, where bluetongue was present. during the nigh ... | 1985 | 2862205 |
| bluetongue and epizootic hemorrhagic disease in white-tailed deer from oklahoma: serologic evaluation and virus isolation. | blood samples were collected from 194 white-tailed deer from 27 locations in oklahoma from 1977 through 1984. sixty-eight (35%) of the deer had antibody against bluetongue virus (btv) and 78 (40%) had antibody against epizootic hemorrhagic disease virus. seropositive deer were detected in each of the 4 geographic quadrants of the state. virus isolation was attempted in 40 deer from the northeast quadrant of oklahoma (1983 through 1984); btv was isolated from 11 deer, but epizootic hemorrhagic di ... | 1987 | 2888426 |
| analysis of the terminal sequences of the genome segments of four orbiviruses. | the dsrna genome segments of bluetongue virus (btv) types 1 and 20 and ibaraki virus (a member of the epizootic haemorrhagic disease (ehd) serogroup) have conserved sequences of six bases at both of their 3' termini. one strand of all the genome segments analysed ends in 3'cauuca ... 5' while the other strand ends in 3'caauuu ... 5'. these conserved sequences are identical to those previously reported for btv types 10 and 11 (a. kiuchi, c. d. rao, and p. roy (1983), "double-stranded rna viruses" ... | 1985 | 2981457 |
| detecting bluetongue virus rna in cell culture by dot hybridization with a cloned genetic probe. | a 70% copy of genome segment 7 of bluetongue virus (btv)-17 has been cloned into the plasmid pbr-322. this cloned btv segment when used as a radioactive probe will hybridize to btv double-stranded rna extracted from cell cultures and dotted onto nitrocellulose paper. this dot hybridization technique is therefore suitable for detecting and identifying btv in cell culture. the specificity of cloned probes is discussed in relation to detecting gene sequences specific for either the bluetongue serog ... | 1985 | 2982893 |
| bluetongue vaccine: cells and/or antibodies. | immunological studies with bluetongue virus have indicated that protection from re-infection involves components of both the humoral and cellular immune response. however, it was found that the humoral response was type-specific, whilst the cellular immune response, particularly through the action of cross-reactive cytotoxic t lymphocytes, gave rise to heterotypic protection. work involving simultaneous and sequential inoculation of live virus and the inoculation of various inactivated preparati ... | 1985 | 2988227 |
| immunologic response of sheep to inactivated and virulent bluetongue virus. | humoral and cellular immune responses of sheep to inactivated and virulent bluetongue virus (btv) were studied. all sheep inoculated with inactivated btv developed btv group-specific nonneutralizing antibodies, as determined by agar-gel immunodiffusion. the development of group-specific, nonneutralizing, complement-fixing antibodies was variable and appeared to be dependent on immunizing btv serotype, sheep breed, and individual variation. virus-neutralizing antibodies were never detected after ... | 1985 | 2988376 |
| ornithodoros coriaceus (pajaroello tick) as a vector of bluetongue virus. | preliminary studies demonstrated that the argasid tick, ornithodoros coriaceus koch, could become infected with bluetongue virus (btv). ticks became infected after feeding through artificial membranes on btv-infected suspensions of cell cultures, chicken embryos, and sheep blood. ticks also became infected after natural feeding on viremic sheep (btv serotype 17) and cattle (btv serotype 11). virus was recovered from the hemolymph and salivary glands of ticks which had ingested btv either through ... | 1985 | 2988383 |
| a preliminary survey of the epidemiology of bluetongue in costa rica and northern colombia. | recent evidence of bluetongue (bt) virus infection of livestock in scattered localities in the neotropics prompted a serologic survey of cattle in colombia and costa rica. in costa rica 48.1% of 1435 bovine animals had bt virus antibody in the agar gel precipitation test (agpt). in colombia 51.8% of 635 cattle were agpt-positive for bt virus. antibody prevalence ranged from over 50% in the lowlands to 0% in costa rica and 19% in colombian cattle above 2000 m altitude. neutralization tests indica ... | 1985 | 2989360 |
| two electropherotypes of bluetongue virus serotype 2 from naturally infected calves. | the first isolation of bluetongue virus (btv) serotype 2 in the u.s.a. was in 1982 from a sentinel herd of cattle at ona, florida. electrophoretic analysis of genome rna revealed that all 16 serotype 2 isolates obtained from this focus of infection had one of two electropherotypes (designated ona a and ona b). all genome segments of ona a and ona b had detectable differences in electrophoretic mobility, with major differences noted for segments 1, 4, 5, 7, 8, 9 and 10. electrophoretic comparison ... | 1985 | 2989416 |
| welcome and objectives. | | 1985 | 2989841 |
| bluetongue and related orbiviruses. proceedings of an international symposium. monterey, california, january 16-20, 1984. | | 1985 | 2989842 |
| subclinical and clinical bluetongue disease in cattle: clinical, pathological and pathogenic considerations. | calves immunized (sensitized) with alcide-inactivated bluetongue virus (btv) developed immunoglobulin (ig) e-specific antibody to btv. development of clinically apparent disease occurred after challenge with virulent btv, and lesions correlated with peak levels of virus-specific ige, an eosinophilic dermatitis, and high concentrations of histamine in the skin. ige may be important in the pathogenesis of clinical bluetongue (bt) disease in cattle. | 1985 | 2989843 |
| reproductive problems associated with bluetongue virus activity in nebraska. | abortions, stillborn calves, neonatal mortalities and excessive numbers of weak, slow-starting newborn have contributed to significant losses within the valuable breeding herds at the roman l. hruska u.s. meat animal research center. conception rates of 70 to 80%, abortion storms and neonatal mortality of 5 to 25% have been observed. vaccination programs control most of the common diseases that contribute to production losses. management and nutrition are considered adequate. excessive dystocia ... | 1985 | 2989844 |
| bluetongue in western nebraska: an area herd study. | | 1985 | 2989845 |
| isolation of bluetongue virus from bull semen. | the efficacy of inoculation of vero cell cultures or intravenous inoculation of chicken embryos in the isolation and titration of seminal bluetongue virus (btv) was studied, as was the toxicity of bull semen for these 2 isolation systems. frozen and thawed btv-contaminated ejaculates collected during periods of viremia from 2 bulls experimentally infected with cell culture-adapted btv serotype 17 were used in isolation, titration and fractionation studies. blood collected from the 2 bulls concur ... | 1985 | 2989846 |
| bluetongue and related orbiviruses: overview of the world situation. | bt is silently spreading in tropical and subtropical countries in the world. serological surveys on bt in developing countries should be intensified and expanded. research is needed to develop simplified virus typing techniques, to develop safe and effective vaccines and to establish procedures for differentiating btv which produces clinical disease from that of low-virulency. it is considered necessary to develop a new disease reporting system which can accommodate both clinical and sub-clinica ... | 1985 | 2989847 |
| salivary gland homogenates from the vector culicoides variipennis may aid in detection of bluetongue virus in chronically infected cattle. | studies were conducted on 2 cows chronically infected with bluetongue virus (btv) acquired in utero from their dam. in previous research, btv had been isolated 4 times from 1 cow and 8 times from the other. btv was undetectable between spontaneous febrile and leukopenic episodes and antibodies to btv were not detectable in the serum. previous work had shown that bites by uninfected females of the vector culicoides variipennis (coquillett) caused virus to recrudesce in the blood to detectable lev ... | 1985 | 2989848 |
| the current taxonomic status of the culicoides vectors of bluetongue viruses. | in the regions where bluetongue (bt) viruses are known to occur the taxomonic literature is generally adequate for confident identification of the commoner species that are the most likely vectors. unfortunately in each region there are difficult taxonomic problems in the accurate determination of some proven or potential vectors. these problems involve the so-called imicola and obsoletus groups of the subgenus avaritia, the variipennis complex in the subgenus monoculicoides and the schultzei gr ... | 1985 | 2989849 |
| vectors of bluetongue virus in australia. | two of the 5 serotypes of bluetongue virus (btv) known from australia have been isolated from field collected insects. serotype 20 was isolated in 1975 from a mixed pool of 214 insects containing several culicoides species. serotype 1 has been isolated from c. (avaritia) fulvus sen & das gupta collected at beatrice hill in the northern territory and from c. (avaritia) brevitarsis kieffer collected at peachester in southeast queensland. all other isolates of bluetongue (bt) group viruses have bee ... | 1985 | 2989850 |
| bluetongue virus isolation from pools of culicoides spp in israel during the years 1981 to 1983. | in 2 permanent suction light trapping stations at bet-dagan and kabri designated to monitor bluetongue virus (btv) activity, 12 isolations were made during 1981 to 1983 from c. imicola. isolation attempts from c. obsoletus, which was dominant in kabri and caught concurrently with c. imicola did not yield btv, while isolations were made from c. imicola. negative isolation atempts were also experienced in c. oxystoma, c. puncticollis and c. circumscriptus, while btv was isolated from c. imicola. s ... | 1985 | 2989852 |
| orbiviruses from culicoides in florida. | between 1980 and 1983, 45,484 culicoides spp. collected in florida near cattle have been examined for orbiviruses by attempted isolation in cell cultures and intravenous (iv) inoculations of embryonated chicken eggs. bluetongue virus (btv) serotype 2 was isolated from a pool of culicoides insignis trapped at ona. this is the 1st recovery of btv from this species representing the 2nd new world species of culicoides from which bt viruses have been isolated. c. insignis is a neotropical form which ... | 1985 | 2989853 |
| observations on larval habitats of suspected culicoides vectors of bluetongue virus in florida. | potential breeding sites for culicoides variipennis (coquillett) and c. insignis lutz, suspected vectors of bluetongue virus (btv) in florida, were examined at 7 livestock facilities located in different geographic regions of the state. the 2 most productive habitats were mud contaminated by effluent from milking parlors (92.3 larvae/sample) and margins of vegetated ponds (18.8 larvae/sample). four species of biting midges, c. crepuscularis malloch, c. haematopotus malloch, c. insignis, and c. v ... | 1985 | 2989856 |
| methodology in preserving field-collected flies for bluetongue virus assay. | preliminary tests were conducted to evaluate the use of phosphate buffered saline (pbs) as a collecting medium for the preservation of flies for virus assay from our bluetongue (bt) study areas in colorado, usa. these tests were made possible by the use of a colony of culicoides variipennis (coquillett) that is highly susceptible to infection with bt virus (btv). | 1985 | 2989857 |
| oral infection of culicoides (diptera, ceratopogonidae) with viral agents, using fine glass needles. | oral infection of haematophagous insects with arboviruses to test their vector competence can be a difficult procedure in the laboratory since "wild caught" insects often prove reluctant to feed, once captured. this paper describes a technique using virus-charged glass needles to infect culicoides spp. orally with bluetongue virus (btv). c. variipennis, a known vector of btv, was found to support virus multiplication with this technique, giving results comparable to those obtained using standard ... | 1985 | 2989858 |
| laboratory infections of culicoides debilipalpis and c. stellifer (diptera: ceratopogonidae) with bluetongue virus. | six species of field-collected culicoides females were used in preliminary laboratory tests: c. biguttatus, c. debilipalpis, c. obsoletus, c. stellifer, c. variipennis and c. venustus. tests were conducted to determine if females would take a blood meal through a membrane, if blood fed females could be maintained in the laboratory for up to 14 days and if they could support replication of bluetongue virus (btv) serotype 11. one pool of c. stellifer (23 specimens) assayed positive for btv 7 days ... | 1985 | 2989859 |
| the virogenesis of bluetongue virus in culicoides variipennis. | a direct immunofluorescence (if) technique was developed to detect bluetongue virus (btv) antigen in culicoides variipennis. after approximately 10 days extrinsic incubation (ei), the if test was as sensitive as virus isolation for detection of infected flies. the if technique was used to determine the virogenesis of btv in the fly. after 6 days ei, virus antigen was detected in most midguts; by 10 days, most head squash preparations contained antigen. other secondary target organs, such as ovar ... | 1985 | 2989860 |
| overview of the orbiviruses. | | 1985 | 2989861 |
| classification of orbiviruses: a need for supergroups of genera. | there has been concern that the present nomenclature system for the members of the reoviridae family, and particularly the orbivirus genus, does not represent the actual relationships exhibited between the members. in order to follow the conventions established by the international committee for the taxonomy of viruses (ictv), it is tentatively proposed that the present reoviridae genera be upgraded in status to the following sub-families: reovirinae, orbivirinae, fijivirinae, cypovirinae, rotav ... | 1985 | 2989862 |
| bluetongue, epizootic haemorrhagic disease of deer and related viruses: current situation in australia. | since 1975 3 serotypes of bluetongue (bt) virus (btv) have been identified in australia: btv1 (csiro156), btv20 (csiro19) and btv21. at present 2 further bt viruses (dpp90 and dpp192) have been isolated from the blood of healthy cattle in the northern territory (nt) and are undergoing identification. there is serological evidence for btv15 infection in western australia (wa) and the nt, and a background level of serological activity to btv serotypes 1 to 17. in addition, over 50 isolations of ep ... | 1985 | 2989863 |
| speciation in orbiviruses. | the definition of orbivirus species should be based on the ability of virus populations to reassort genetic information. application of the definition of biological species to orbiviruses enables consideration to be given the evolutionary tendencies of virus populations and to mechanisms for generating diversity within orbiviruses. | 1985 | 2989864 |
| an electron microscopic study of blood cells from calves experimentally infected with bluetongue virus. | cellular elements from blood samples of calves experimentally inoculated with a quadrivalent mixture of bluetongue virus (btv) types 10, 11, 13 and 17 were examined by transmission electron microscopy (tem). virus-like particles were observed within cytoplasmic vacuoles of infected agranular leukocytes from inoculated calves on postinoculation day (pid) 14. no virus-like particles were seen associated with other cellular blood elements nor were they observed in blood samples obtained prior to vi ... | 1985 | 2989865 |
| morphology of bluetongue virus-infected aedes albopictus (c6/36) cell culture. | morphological changes observed in bluetongue virus (btv)-infected aedes albopictus (c6/36) suspension cell culture at 28 c were compared to those observed in mammalian stationary cell culture at 37 c. the presence of cytoplasmic macrotubules, viroplasms and progeny virions was confirmed and appears to be the same as seen in mammalian cell culture. in addition progeny virions were observed budding from cell membranes where they appeared to acquire a lipoprotein envelope. intranuclear macrotubules ... | 1985 | 2989866 |
| the search for bluetongue viruses in australia. | in the 200 years that cattle and sheep have been present in australia no evidence of bluetongue (bt) disease has ever been reported. the discovery in 1977 that a virus isolated from culicoides species collected in 1975 was bluetongue virus (btv) triggered a search for bt viruses and their vectors throughout the country. between 1975 and 1983, 46 strains of 5 serotypes of btv were isolated by various workers from the blood of subclinically infected sentinel cattle or from culicoides species. the ... | 1985 | 2989867 |
| isolation and propagation of bluetongue virus in embryonating chicken eggs. | the incidence of bluetongue (bt) disease in sheep in israel during 1964-1982 was presented. the intravenous (iv) and the yolk-sac (ys) routes of inoculating embryonating chicken eggs (ece) for primary isolation and propagation of bt virus (btv) were compared and assessed. it was shown that the iv route of inoculation was about 100- to 1,000-fold more sensitive than the ys route; also, by the iv route, virus isolation was more rapid and assays were more clear cut. about 30% of virus isolations fr ... | 1985 | 2989868 |
| isolation and identification of bluetongue virus: a serotype new to the u.s. | there are 5 known serotypes of bluetongue (bt) virus (btv) in the us: 2, 10, 11, 13 and 17. the most recently discovered us serotype, btv 2, was isolated from blood collected from cattle at ona, florida in 1982. isolations were made from the september through november bleedings and from 1 pool of culicoides insignis lutz collected in october. seventeen viral isolates were obtained by injecting the samples into embryonated chicken eggs (ece) followed by serial passage onto bhk-21 cells. a single ... | 1985 | 2989869 |
| biochemical characterisation of australian orbiviruses. | there are over 30 antigenically distinct orbiviruses found in australia, including members in the bluetongue virus (btv) and epizootic hemorrhagic disease of deer virus (ehdv) serogroups. genomic rna profiles were analysed by polyacrylamide gel electrophoresis (page) on both 10% laemmli and tris-borate-edta-(tbe)-urea gels. there was considerably more variation in the rna profiles in laemmli gels than was apparent in the tbe-urea gels. since the latter system separates on molecular size, then pr ... | 1985 | 2989870 |
| immune response against the purified serotype specific antigen of bluetongue virus and initial attempts to clone the gene that codes for the synthesis of this protein. | sheep were injected with different amounts of purified protein p2 of bluetongue (bt) virus (btv). about 3 x 50 mcg was required for the induction of neutralizing antibodies. sheep injected with 3 x 10 mcg were, however, still largely protected when challenged with virulent virus. this has suggested the possibility of using p2 as a subunit vaccine and initiated an investigation of the possibility of synthesizing p2 by dna-recombinant technology. in order to clone the gene that codes for the synth ... | 1985 | 2989871 |
| molecular cloning and hybridization studies on bluetongue virus serotype 17. | the dsrna of bluetongue virus (btv) serotype 17 has been reverse transcribed and dsdna copies of the viral rna have been cloned into the plasmid vector pbr-322. segments ranging from 3 kilobases to less than 500 bases have been cloned and at present 1 of the clones has been identified by hybridization to the genome segment of its origin (genome segment 7). identification of further clones is proceeding. the techniques for northern blotting btv dsrna onto 2-aminophenylthioether (apt) paper and th ... | 1985 | 2989872 |
| cloning and nucleotide sequencing of bluetongue virus genomes. | this is the 1st report of molecular cloning of bluetongue virus (btv) gene using dna recombinant techniques. a number of complete and overlapping clones of btv genes have been cloned into pbr322 by standard procedures with some modification. the full length clones were confirmed by matching the terminal cdna nucleotide sequences with those previously determined for the termini of double-stranded genomic rna (rao et al., 1983). the complete sequence of the cdna clone of rna segment 3 of us seroty ... | 1985 | 2989873 |
| bluetongue in the united states. | the virus of bluetongue (bt) was 1st isolated and identified in the us in 1952 from sheep in california. a disease in sheep in texas (soremuzzle) was observed in 1947, reported in 1952 and similarities to bt were discussed. it is possible bt existed in texas for several years prior to that time. there are 23 immunologic serotypes of bt, and 5 are known to occur in the us. these are types 10, 11, 13, 17 and 2, the latter having been recognized only in 1983 in cattle in florida. in the us, bt was ... | 1985 | 2989874 |
| analysis of the terminal sequences of the genome segments of four orbiviruses. | the rna sequences of the terminal regions of the genome segments of 4 different orbiviruses were analysed. in 3 of these [bluetongue virus (btv) types 1 and 20 and ibaraki virus, a member of the epizootic hemorrhagic disease (ehd) serogroup], 1 strand of all of the genome segments analysed ends in 3'caauuu...5' while the other strand ends in 3'cauuca...5'. these conserved sequences are identical to those reported for btv types 10 and 11. the 3' terminal sequences of segments 3 and 10 of the btv ... | 1985 | 2989875 |
| genome rnas of virulent and attenuated strains of bluetongue virus serotypes 10, 11, 13 and 17. | an improved system was developed for the electrophoretic resolution of bluetongue virus (btv) genome segments. this procedure was used to compare the genome segments of wild type (w) and vaccine (v) strains of btv serotypes 10, 11, 13 and 17. numerous alterations in the migration of individual genome segments could be detected between w and v strains of each serotype, suggesting that many mutations had occurred during attenuation of the v strains. in addition, electrophoretic polymorphisms not p ... | 1985 | 2989876 |
| immunochemical analyses of australian bluetongue virus serotypes using monoclonal antibodies. | in order to characterize the immunochemical role of bluetongue virus (btv)-specified proteins and provide reagents capable of defining the serological relatedness of bluetongue (bt) serotypes and their relationship with other orbiviruses, a panel of 16 igg monoclonal antibodies was raised to the australian btv serotypes, isolate csiro156 (btv 1), csiro19 (btv20) and csiro154 (btv21). analyses of virus-coded polypeptide specificities of these monoclonals using enzyme-linked immunosorbent assay (e ... | 1985 | 2989877 |
| growth characteristics of virulent and attenuated strains of bluetongue virus serotypes 10, 11, 13 and 17. | the growth properties of wild type (wt) and live, attenuated vaccine (v) strains of bluetongue virus (btv) serotypes 10, 11, 13 and 17 were compared. all btv strains produced maximal yields when grown at 34 c and harvested 24-36 hr after infection. the 4 v strains were temperature-sensitive (ts) for growth at 39 c as compared to the corresponding wt strains. the 4 v strains were ts for plaque formation when 37 c was used as the nonpermissive temperature. one-step growth curves showed that only t ... | 1985 | 2989878 |
| gamma ray sensitivity of bluetongue, ehd and african horsesickness viruses and their precipitating and complement fixing antigens. | | 1985 | 2989879 |
| role of the immune system in bluetongue host-viral interactions. | immune responses involving both b and t lymphocyte subpopulations have been demonstrated in sheep and cattle. the immune responses appear to be associated with the modulation of disease expression in sheep and cattle. an immature immune system in fetal lambs and calves permits virus to replicate with little or no host interference. viral teratogenicity may consequently lead to malformed newborns, fetal deaths, abortion or readsorption. adult sheep and cattle appear to respond somewhat differentl ... | 1985 | 2989880 |
| an overview of diagnostics for bluetongue. | | 1985 | 2989881 |
| bluetongue: diagnostic/antigenic interpretation. | | 1985 | 2989883 |
| problems in the interpretation of diagnostic tests due to cross-reactions between orbiviruses and broad serological responses in animals. | tests presently used for the diagnosis of infections by bluetongue virus (btv) or related orbiviruses are based on the use of 2 types of serological reactions. those that are considered group-reactive tests are the agar gel diffusion precipitin (agdp), complement-fixation (cf) and fluorescent antibody tests and those that are considered type-specific are a wide variety of virus neutralization tests (50% and 80% plaque reduction, plaque inhibition and microtiter neutralization) and cross-protecti ... | 1985 | 2989884 |
| bluetongue: a review of the immune response of sheep and cattle to bluetongue virus infection. | | 1985 | 2989885 |
| the use of serology in bluetongue epidemiology. | | 1985 | 2989886 |
| bluetongue and related orbivirus diagnosis in the united states. | the serologic test for bluetongue (bt) that was used in the us from 1968 to 1980 to qualify animals for export was the modified direct complement-fixation (mdcf) test. the mdcf test was replaced by the immunodiffusion (id) test in 1980. in january 1984, there were 70 laboratories approved by the usda to conduct bt id export testing. both tests are used at the national veterinary services laboratories (nvsl) for the serologic diagnosis of suspected cases of bt and/or epizootic hemorrhagic disease ... | 1985 | 2989887 |
| an overview of colorado tick fever. | certain features of colorado tick fever (ctf) virus and the disease it causes may be relevant to studies on bluetongue virus (btv), or other orbiviruses. rapid and easy detection of viral antigen in infected tissues and peripheral blood cells by immunofluorescence staining facilitate diagnosis of the disease. the prolonged (3-4 months) viremia is due to persistent intracellular infection, particularly of erythrocytes, in which the virus is protected from antibody or other host defense mechanisms ... | 1985 | 2989888 |
| importance of ovine cytotoxic t cells in protection against bluetongue virus infection. | in sheep, bluetongue virus (btv) was shown to induce anti-btv cytotoxic t lymphocytes (ctl) and their effect to be maximal around 14 days post inoculation (p.i.) of virus. using cellular adoptive transfer techniques in monozygotic sheep, such cells were shown to partially protect animals from btv challenge. a short-lived cross-protective mechanism was identified involving thoracic duct lymphocytes (tdl) and nonneutralising antibody. these observations suggest that t lymphocytes play an important ... | 1985 | 2989889 |
| humoral and cellular immune response of sheep to bluetongue virus. | plaque cloned strains of the 4 us bluetongue (bt) virus (btv) serotypes (10, 11, 13 and 17) were pathogenic to sheep and induced mild clinical responses. the clinical responses coincided with the highest titer of viremia reached by day 7 following primary infection. the 4 btv strains were immunogenic, inducing group-specific (precipitating) and type-specific (neutralizing) antibodies. primary infection induced an immune response which protected the animals against secondary challenge with the ho ... | 1985 | 2989890 |
| monoclonal antibodies and bluetongue virus diagnosis. | a blocking enzyme linked immunosorbent assay (elisa) is described for the detection of group specific antibodies to bluetongue virus (btv). the test is based upon the interruption of the reaction between btv antigen and a group specific monoclonal antibody raised against btv by the addition of serial dilutions of either bovine or ovine test sera. the presence of group specific antibodies to btv in the test serum, results in inhibition of the monoclonal antibody which is detected as a reduction i ... | 1985 | 2989891 |
| monoclonal antibodies raised against bluetongue virus detect viral antigen in infected tissues using an indirect immunoperoxidase method. | an indirect immunoperoxidase method was developed to determine the presence of viral antigen in bluetongue virus (btv) infected tissues. embryonating chicken eggs were infected with each of the 4 united states btv serotypes (10, 11, 13, 17) and the chorioallantoic membranes were subsequently formalin fixed and embedded in paraffin. the infected membranes were examined for the expression of viral antigen. monoclonal antibodies raised against btv 17 (bt 21a and bt 98a) were used as the primary ant ... | 1985 | 2989893 |
| plaque neutralization cross reactivity of post infection bovine sera amongst bluetongue virus serotypes. | | 1985 | 2989894 |
| epidemiology of bluetongue in australia: the vertebrate hosts. | ruminants became established in australia after european settlement which commenced in the late 18th century. bluetongue (bt) disease has never been suspected in cattle or sheep in this country. the species of ruminants found to have antibodies to bt and epizootic haemorrhagic disease (ehd) viruses are cattle, buffaloes, deer, goats and sheep. no antibodies have been found in pigs, horses, marsupials (kangaroos and wallabies) or humans, even in areas of high prevalence of bt and ehd infection. t ... | 1985 | 2989897 |
| bluetongue epidemiology in the middle east. | | 1985 | 2989898 |
| epidemiology of two orbiviruses in california's native wild ruminants: preliminary report. | between 1978 and 1983 we collected more than 1,500 serum samples from california's native black-tailed deer (odocoileus hemionus columbianus), 4 races of mule deer (o. h. sp.), tule elk (cervus elaphus nannodes), roosevelt elk (c. e. roosevelti), pronghorn antelope (antilocapra americana), california bighorn sheep (ovis canadensis californiana), peninsular bighorn sheep (o. c. cremnobates) and desert bighorn sheep (o. c. nelsoni) and analyzed them for agar gel precipitating (agp) antibodies to b ... | 1985 | 2989899 |
| serotypes of bluetongue virus present in saudi arabia. | the widespread occurrence of infection with bluetongue virus (btv) in saudi arabia has been demonstrated by immunodiffusion testing. subsequently, 31 sheep sera and 1 goat serum with clear precipitating activity were examined by neutralization test using the 22 reference serotypes of btv. only 12 sheep sera neutralized 1 or more of btv serotypes: 6 (1 serum), 14 (2 sera), 17 (4 sera), 19 (1 serum) and 20 (11 sera). the goat serum neutralized only serotype 19 of btv. on the other hand, 19 sheep s ... | 1985 | 2989900 |
| bluetongue: virological and epidemiological observations in israel. | bluetongue (bt) has become endemic in israel. five bt virus (btv) types have been identified, of which btv 4 is dominant. results of the regular monitoring of viral activity in ruminants and culicoides, including country-wide serological surveillance in bovines and virus recovery trials from bovine semen, are represented. the seasonal and geographical distribution, susceptibility of various species and applied preventive measures are discussed. further studies are needed to establish the interse ... | 1985 | 2989902 |
| first report of bluetongue antibody in chile. | a sample of 1,752 bovine sera collected from 99 herds throughout the tenth region, chile, from march 8 to november 20, 1982, was analyzed for bluetongue (bt) antibodies using the immunodiffusion (id) test. the prevalence of bt virus (btv) antibody was 19.6%. sixty-four (64.6%) herds showed at least 1 positive animal, which suggests an important antibody distribution in the area. the examination of 500 sera of sheep in 14 herds indicated the following results: 8/500 animals were positive in 5/14 ... | 1985 | 2989903 |
| bluetongue virus infection in costa rican and colombian cattle. | bluetongue virus (btv) group antibodies are widely distributed in costa rica and northern colombia; prevalence is highest at lowest altitudes. clinical evidence of bluetongue (bt) infection in cattle is not seen. evidence exists of the circulation of btv serotypes 6 and 14 in costa rica and btv serotype 12, 14 and 17 in northern colombia in the period 1981-1983. culicoides insignis is implicated as a probable vector in colombia. | 1985 | 2989904 |
| serological observations on the epidemiology of bluetongue virus infections in the caribbean and florida. | serological surveys of cattle, sheep and goats have confirmed that infection with bluetongue virus (btv) is common in florida, puerto rico and st. croix in the usa, in the caribbean countries of jamaica, st. kitts/nevis, antigua, st. lucia, barbados, grenada, trinidad and tobago, and the bahamas, and in the south american countries of guyana and suriname. in most countries, over 50% of ruminant livestock have antibody to btv as assessed by the bluetongue immunodiffusion (btid) test. a sentinel a ... | 1985 | 2989905 |
| epizootiological study of bluetongue virus infection in california livestock: an overview. | an epidemiologic program was undertaken in california to study bluetongue virus (btv) infection in domestic livestock. the study was designed to determine: a) prevalence of btv infection, b) serotypes of btv actively causing infection, c) seasonality of infection and d) species infected. a total of 8,751 cattle, 14,639 sheep and 4,785 goats were tested over the 3 1/2 year study. serologically, 41% of the cattle, 42% of the sheep and 21% of the goats were positive. virologically, 2.4% of the catt ... | 1985 | 2989906 |
| epidemiologic study of bluetongue virus on the tejon ranch, california: vector, host, virus relationships. | culicoides gnats were monitored from april through november, 1981, on the tejon ranch, kern county. levels of gnat breeding were determined by quantitative sampling of substrate from intermittent and permanent water sources. adult populations were measured by light trap collections taken around pens holding sentinel beef cattle, dairy calves, sheep, goats and deer. adult gnats were collected in the environs of the study area, and blood samples were obtained from sentinel animals for laboratory d ... | 1985 | 2989907 |
| molecular epidemiology of two us orbiviruses: bluetongue virus and epizootic hemorrhagic disease virus. | the degree of relatedness between 4 us serotypes (10, 11, 13 and 17) of bluetongue (bt) virus (btv) were determined by both oligonucleotide fingerprint analyses of double-stranded (ds) rna as well as tryptic peptide analyses of viral coded polypeptides. similar studies were undertaken using different alternate isolates of particular serotypes as well as 2 serotypes (1 and 2) of epizootic hemorrhagic disease (ehd) virus (ehdv), a closely related serogroup of orbiviruses. the results indicate that ... | 1985 | 2989908 |
| epidemiologic implications of the genetic variations of bluetongue virus. | the segmented rna genome of bluetongue (bt) virus (btv) provides for considerable diversity. this diversity has been seen in biochemical and biophysical analyses of the numerous strains of btv as well as in clinical and immunologic responses of ruminant animals to btv infection. this report describes the preliminary characterization of a unique btv serotype 11 population recovered during 4 months in 1982 from 40 naturally infected animals including cattle, sheep and a goat. the strains of btv se ... | 1985 | 2989909 |
| vaccines for bluetongue and other orbiviruses from a regulatory viewpoint. | | 1985 | 2989911 |
| use of a quadrivalent modified-live bluetongue virus vaccine in wildlife species. | three hundred and twenty-seven animals comprised of deer, mouflon sheep and bighorn sheep were vaccinated with an experimental quadrivalent, modified-live, bluetongue virus (btv) vaccine. no untoward effects due to the vaccine were noted nor were abortions observed in vaccinated pregnant mouflon sheep. precipitating antibodies to btv and epizootic hemorrhagic disease (ehd) virus were identified in the serum of several animals prior to vaccination. virus neutralizing antibodies to 3 of the 5 sero ... | 1985 | 2989912 |
| immune response of mice and sheep to bluetongue virus inactivated by gamma irradiation. | gamma irradiation is being tested as a means of inactivating bluetongue virus (btv) for use in vaccines. exposure of btv 17 to various levels of irradiation revealed that a dose of approximately 0.6 megarad was required to reduce the virus titer by one log10, or 90%. to test the immunogenicity of irradiated btv, mouse brain passaged virus and concentrated cell culture passaged virus were inactivated by 6 megarads of gamma irradiation, and vaccines were prepared by emulsifying the virus preparati ... | 1985 | 2989913 |
| potency and efficacy of inactivated bluetongue virus vaccines. | bluetongue virus (btv) was chemically inactivated and was shown to elicit neutralizing antibodies in vaccinated rabbits and sheep. in sheep, the neutralizing antibody was shown to be protective by immunity challenge with virulent virus. these studies have shown the feasibility of safe and effective inactivated vaccines for bluetongue (bt) disease of sheep. | 1985 | 2989914 |
| control of bluetongue virus spread by embryo transfer. | | 1985 | 2989915 |
| who/fao working team report: pathology. | | 1985 | 2989916 |
| who/fao working team report: entomology. | a summary of the more important concerns of the working team with particular reference to bluetongue (bt) virus (btv), is as follows: with the exception of australia, the us, and possibly parts of africa, there are almost no concrete data that could be used to direct control efforts against the responsible vector(s) of btv in a specific geographic area. in australia, a broad plan of attack yielded data that showed that members of the subgenus avaritia are the primary vector species. it has been ... | 1985 | 2989917 |
| who/fao working team report: virology. | | 1985 | 2989918 |
| "white eye calf" syndrome in oregon associated with bluetongue and epizootic hemorrhagic disease viruses. | | 1985 | 2989919 |
| who/fao working team report: molecular virology. | | 1985 | 2989920 |
| who/fao working team report: immunology. | | 1985 | 2989921 |
| who/fao working team report: epizootiology. | | 1985 | 2989922 |
| the history of bluetongue. | | 1985 | 2989923 |