structural and growth characteristics of two avian reoviruses.two virus strains which had been suspected to be the etiological agents of infectious bursitis (gumboro disease) and of inclusion body hepatitis of chickens were characterized by their morphology, their peptide composition and the segmented genome of their double-stranded rna to be typical reoviruses. although the 2 avian strains did not clearly differ in their serological behaviour, the size of some of their rna segments were not identical. both strains replicated in tissue cultures prepared fr ...1975170888
an outbreak of infectious bursal disease (ibd) of chickens in nigeria. 1975175539
structural and growth characteristics of infectious bursal disease virus.the infectious bursal disease virus is not enveloped and has a diameter of 60 nm and a density of about 1.32 g/ml. it contains two pieces of single-stranded rna with molecular weights close to 2 x 10(6). the capsid is made up of four major polypeptides with molecular weights of 110,000, 50,000, 35,000, and 25,000. the virus replicates in chicken embryo fibroblasts rather than in epitheloid cells. after an eclipse period of 4 h, virus production reaches a maximum about 12 h later. the virus has n ...1976176463
[the "vaccination reaction" syndrome of broilers after vaccination against newcastle disease and infectious bronchitis (author's transl)].in a part of the broiler flocks vaccinated against newcastle disease (n.c.d) and infectious bronchitis (i.b.), disease symptoms of lingering nature have been observed, generally in the second half of the rearing period. in a practical investigation with weekly examinations of chickens, supplemented by a serological examination of twenty-four animals per flock at the age of six weeks, it was hoped to establish the factors responsible for this "vaccination reaction". in the district under notice t ...1976179162
immunosuppressive effect of a naturally acquired subclinical bursal agent infection on vaccination against newcastle disease.a naturally acquired subclinical infection of infectious bursal agent was shown to be the probable causative factor of marked immunosuppression of newcastle disease vaccine in young chicks. old hens maintained in the same contaminated environment did not exhibit immunosuppression.1976186932
prevention of avian lymphoid leukosis by induction of bursal atrophy with infectious bursal disease viruses.five groups of genetically susceptible chickens were inoculated at hatching with lymphoid leukosis virus; four of these were given infectious bursal viruses of varying virulence at 14 days of age and one group was not inoculated (control). all chickens in the control group developed evidence of lymphoid leukosis by 180 days. two groups given relatively virulent bursal disease viruses, which destroyed bursal lymphoid cells, did not develop lymphoid leukosis. treatment with avirulent vaccines had ...1978210556
the use of an inactivated infectious bursal disease oil emulsion vaccine in commercial broiler parent chickens. 1979222040
immunofluorescent studies of early virus propagation after oral infection with infectious bursal disease virus (ibdv). 1979231357
characterization of immunosuppression in chickens by infectious bursal disease virus.chickens were infected with infectious bursal disease (ibd) virus in ovo or at different times posthatching to 6 weeks of age. the b- and t-cell responses in the lymphoid tissues and blood were examined sequentially to 8 weeks of age by using indirect immunofluorescence. the proportion of b-cells was consistently lower in infected birds than in controls, especially in chicks infected as embryos or at 1 day old. the proportion of t-cells increased following these early infections but was slightly ...1979232660
genetic mechanisms of antigenic variation in infectious bursal disease virus: analysis of a naturally occurring variant virus.the major immunogenic protein vp2 from a pathogenic field isolate (variant a virus) of infectious bursal disease virus (ibdv) was cloned and sequenced to examine antigenic variations. the vp2 open reading frame consists of 1509 nucleotides and codes for a 503 amino acid protein. overall, the vp2 amino acid sequence of the variant a virus shares 98.6% identity with vp2 genes from other published ibdv strains. however, within the central region of vp2 (amino acids 222-334) lies a highly divergent ...19921329340
susceptibility of chicken monocytic cell lines to infectious bursal disease virus. 19921322719
relationship of common avian pathogen antibody titers in so-called chicken anemia agent (caa)-antibody-positive chicks to titers in caa-antibody-negative chicks.antibody titers for infectious bursal disease virus (ibdv), infectious bronchitis virus, newcastle disease virus, and reovirus from chicks with chicken anemia agent (caa) antibodies were compared with antibody titers from their caa-antibody-negative counterparts. these comparisons were made in 396 chickens that were 1 day, 2 weeks, 8-9 weeks, 10 weeks, 17 weeks, or 29-32 weeks old. only one serum sample was collected from any given chick or chicken. there were no significant differences between ...19921320864
recent advances in avian virology.selected, recent research on the following avian diseases, and their causative viruses, has been reviewed: chicken anaemia, infectious bursal disease, turkey rhinotracheitis, avian nephritis, fowlpox, influenza, infectious bronchitis and turkey enteritis.19921319788
serological prevalence of infectious bursal disease in madhya pradesh and maharashtra. 1979231575
studies on interferon induction by infectious bursal disease virus (ibdv). ii. interferon production in white leghorn chickens infected with an attenuated or pathogenic isolant of ibdv.infectious bursal disease virus (ibdv) isolants that differed in virulence for chickens, were compared as to: 1) induction of interferon in serum and tissues; and 2) stimulation of ibdv serum antibody. specific-pathogen-free chickens were infected at one day and four weeks of age by the subcutaneous and intranasal routes of inoculation. the pathogenic isolant induced a more generalized interferon response than the attenuated isolant, independent of age or route of inoculation. pathogenic ibdv st ...1979230805
morphologic changes in the bursa of fabricius of chickens after inoculation with infectious bursal disease virus.sequential morphologic changes in the bursa of fabricius were studied after oral inoculation of 1-day-old chicks with infectious bursal disease virus (ibdv). the epithelial surface morphology was studied by scanning electron microscopy, whereas the ibdv replication was sequentially followed by immunofluorescence and transmission electron microscopy. the earliest detectable changes in the bursal epithelium were evident at postinoculation hour (pih) 48. they were characterized by reduction in numb ...1979230768
effects of early infectious bursal disease virus infection on immunity to newcastle disease in adult chickens.experimental infection with infectious bursal disease virus (ibdv) at hatching or at 3 weeks of age in white leghorn chickens without maternally derived antibodies to ibdv resulted in a depression in the antibody response of chickens to newcastle disease vaccination (ndv) at 4 weeks of age and increased the susceptibility of those birds to challenge with virulent ndv. infection of non-ibdv immune chickens with ibdv at hatching, but not at 3 weeks of age, also depressed the antibody response of c ...1979226946
infectious bursal disease viral infections. ii. the relationship of age, complement levels, virus-neutralizing antibody, clotting, and lesions.experimental infection with infectious bursal disease virus (ibdv) reduced the complement (c) titer in 8-week-old chickens on days 3, 5, and 7 postinfection. since the c titer was much lower in normal 2-week-old chickens than in normal 8-week-old chickens it could not be determined whether there was a reduction in titer during the infection process. virus-neutralizing antibody rose rapidly following infection in both 2- and 8-week-old chickens. hyper-immune serum given during infection in an att ...1979226048
antigenic characterization of ibdv field isolates by their reactivity with a panel of monoclonal antibodies.recently infectious bursal disease virus isolates have been described in usa displaying an antigenic drift. many of the new isolates were very virulent for chickens. in several european countries severe outbreaks of gumboro disease have also been reported from vaccinated and non-vaccinated flocks. since vaccinated spf birds were shown to be protected against challenge infection with the new isolates under laboratory conditions, a more detailed investigation of the european isolates is wanted. th ...19902155771
pathogenicity and immunosuppressive properties of infectious bursal disease "intermediate" strains.this study was conducted to test the pathogenicity and immunosuppressive effects of seven commercially available infectious bursal disease (ibd) vaccines. these vaccine strains are intermediate in their pathogenicity in susceptible specific-pathogen-free (spf) chickens. one-day-old and 3-week-old spf chickens were vaccinated with these vaccines. two weeks after ibd vaccination, they were vaccinated with newcastle disease virus (ndv). the pathogenic and immunosuppressive effects of the ibd vaccin ...19902157393
single and combined infections of specific-pathogen-free chickens with infectious bursal disease virus and an intestinal isolate of reovirus.the susceptibility of 1-day-old and 7-day-old specific-pathogen-free chickens to infection with a virulent strain of infectious bursal disease virus (ibdv) or an intestinal isolate of avian reovirus, or a combination of the two, was investigated. chickens infected with ibdv and reovirus had more severe pathological lesions than chickens infected with either virus alone, and prior infection with ibdv enhanced the pathogenicity of enteric reovirus. virus recovery was attempted from bursa, spleen, ...19902157397
standardization of the quantitative agar gel precipitin test for antibodies to infectious bursal disease. 1979225328
infectious bursal agent vaccination of chicks from infectious bursal agent-vaccinated dams.chicks from infectious bursal agent-vaccinated broiler breeders were vaccinated with a commercial infectious bursal agent vaccine at intervals after hatching. bursas from some of these chicks were examined for infectious bursal agent-specific fluorescence four days after vaccination and bursas from others were examined for histological lesions of infectious bursal disease 21 days after vaccination. serological studies were conducted to determine if active immunity to infectious bursal agent foll ...1979219952
experimental infection in specific-pathogen-free chicks with avian reovirus and avian nephritis virus isolated from broiler chicks showing runting syndrome.avian reovirus (arv) and avian nephritis virus (anv) were individually isolated from runty 10-day-old broiler chicks. the arv isolate, ir-r, the anv isolate, ir-n, and the reference strain of anv, g-4260, were inoculated orally into 1-day-old chicks of two specific-pathogen-free (spf) chicken lines, 151 and pdl-1. growth retardation without the presence of gross lesions was clearly observed at 7 and 14 days postinoculation (pi) in chicks of both lines inoculated with the ir-r strain. on the othe ...19902164386
computer simulation of gumboro disease outbreak. i. construction of models g-1 and g-2. 1978216928
broiler-breeder vaccination against infectious bursal disease and persistence of maternal antibody in progeny. 1978210922
diagnosis of avian viral diseass by electron microscopy.clinical material from avian species was examined directly by electron microscopy for the presence of viruses. mycoplasma-like and coronavirus-like particles were found in chicken feces. these particles did not appear to be associated with disease and were not propagated in the laboratory. infectious bursal disease virus was readily detected in impression smears of bursas from experimentally infected birds. poxviruses were demonstrated in smears made from canarypox lesions. difficulty in disting ...1978205149
influence of infectious bursal disease on the development of immunity to eimeria tenella.specific-pathogen-free (spf) chicks infected with infectious bursal disease (ibdv) virus at one day of age or midway (7 days) through a two-week immunization program for eimeria tenella showed significantly less (p less than or equal to 0.05) protection against coccidal challenge as measured by lesion scores than chicks given ibdv after 14 days of coccidial immunization. the chicks showed complete protection to later coccidial challenge administered on day 21. bursae were markedly smaller from i ...1977204282
effect of infectious bursal disease on the severity of eimeria tenella infections in broiler chicks.a study was initiated to determine whether prior exposure to infectious bursal disease virus (ibdv) influenced the susceptibility of young broiler chicks to eimeria tentella infections. when one-day-old chicks infected with ibdv were subsequently challenged with e. tenella at 7 days of age, they suffered significantly higher mortality and lesion scores than their hatchmates which were not exposed to ibdv. initial exposure to ibdv also had an effect on the development of e. tenella induced hemorr ...1977203907
plaque reduction neutralization test for the serodiagnosis of infectious bursal disease. 1977192932
effect of infectious bursal disease on the response of chickens to mycoplasma synoviae, newcastle disease virus, and infectious bronchitis 35 days of age, chickens which as 1-day-old chicks were inoculated with the infectious bursal disease virus (ibdv) had significantly lower antibody titers against mycoplasma synoviae, newcastle disease virus, and infectious bronchitis virus than did those never inoculated with ibdv. the ibdv also had a marked effect on the development of air-sac lesions. birds infected with ibdv that were later inoculated with m synoviae (day 14), newcastle disease virus (days 14 and 28) experienced an increa ...1977190926
immunization of adult hens against infectious bursal disease virus. 1976183653
electron-microscope studies on the pathogenesis of infectious bursal disease after intrabursal application of the causal virus.intrabursal application of infectious bursal disease virus (ibdv) is of advantage in studying sequential morphological events since the time of infection of the bursa is exactly known. a highly pathogenic strain caused first clinical symptoms 12 hr postinfection (pi) and death 24-30 hr pi. these are respectively 12 and 18 hr earlier than after per-oral infection. numerous virus particles 53-58 nm in size, arrayed in a crystalline pattern and not surrounded by a membrane, are first found 6 hr pi ...1976183649
immunodeficiency in the chicken. iv. an immunological study of infectious bursal disease.chickens inoculated orally with infectious bursal disease virus (ibdv) 1 day after hatching subsequently showed a 50% incidence of immunodeficiency but little mortality. antibody responses against ibdv and to immunization with sheep red blood cells (srbc) or human serum albumin (hsa) were suppressed. serum igg concentration was decreased while igm occurred exclusively in its 7s monomeric form (migm). an allotypic marker of chicken igm (mla) was lacking in migm derived from ibdv-infected birds. t ...1976177236
occurrence of acute infectious bursal disease with high mortality in japan and pathogenicity of field isolates in specific-pathogen-free chickens.highly virulent infectious bursal disease virus (ibdv) was isolated from field cases, and the pathogenicity of the isolates was examined in specific-pathogen-free chickens. chickens inoculated with the isolates developed severe clinical disease with a high mortality rate. histopathologically, infectious bursal disease was characterized by bursal and thymic necrosis, aplastic anemia, acute hepatitis with fatty change, and systemic inflammatory response. in addition to functional abnormalities in ...19921329709
de novo initiation of specific cell-mediated immune responsiveness in chickens by transfer factor (specific immunity inducer) obtained from bovine colostrum and milk.transfer factors (tf) were prepared from colostrum and milk of bovines previously immunized with antigens obtained from coccidioides immitis, infectious bovine rhinotracheitis virus, or from the viral agents responsible for avian newcastle disease, laryngotracheitis disease or infectious bursal disease. the ability of bovine tf to transfer specific cell-mediated immune responsiveness to a markedly xenogenic species was studied using specific pathogen free (spf) and standard commercial (sc) chick ...19882897772
detection of infectious bursal disease virus in digested formalin-fixed paraffin-embedded tissue sections by polymerase chain reaction. 19921333820
immunosuppressive effect of a highly virulent infectious bursal disease virus isolated in japan.the immunosuppressive effect of infectious bursal disease virus (ibdv) on vaccination against newcastle disease (nd) was compared among 2-, 3-, and 4-week-old chickens inoculated with the highly virulent ibdv field isolate 90-11 and the reference serotype 1 strain gbf-1. in all age groups, isolate 90-11 severely suppressed antibody response to nd vaccination and protective vaccinal immunity against nd. in contrast, chickens inoculated with strain gbf-1 and vaccinated with nd vaccine were well pr ...19921336662
infectious bursal disease--b cell dependent immunodeficiency syndrome in chickens.infectious bursal disease of chickens can run an acute lethal course, or death can result from a b cell-dependent immunodefect due to destruction of the bursa of fabricius following infection with infectious bursal disease virus (ibdv). this member of the birnaviridae has been characterized, the nucleotide sequence and coding capacity of the two genomic segments of dsrna has been determined, and the functional significance of the four structural proteins has been largely elucidated. the antigeni ...19911656933
determination of infectious bursal disease virus titration and neutralization endpoints using fluorogenic automated method for determining infectious bursal disease virus (ibdv) titration and neutralization endpoints is described. the method employs the fluorogenic ester carboxyfluorescein-diacetate (cfda) to stain cell monolayers in 96-well plates and a fluorescence-concentration analyzer. titration results are compared with immunofluorescence and plaque assay titers. virus-neutralization endpoint determination is objective, and the endpoints of replicate tests were equivalent or within one dilu ...19911659366
ascites syndrome in spf light sussex ascites syndrome was induced in 17 to 28 per cent of specific pathogen-free (spf) light sussex (lsx) chickens given a low protein (16 per cent crude protein) high calcium (3.5 per cent calcium) layer crumble feed on two separate occasions 6 months apart. affected chickens had increased right ventricular weight as a proportion of either total heart weight or live-weight at 3 weeks of age, compared with non-affected lsx chickens on the same feed, thus indicating right ventricular hypertrophy. t ...19911663140
biophysical and biochemical characterization of five animal viruses with bisegmented double-stranded rna genomes.infectious pancreatic necrosis virus of fish, infectious bursal disease virus of chickens, tellina virus and oyster virus of bivalve molluscs, and drosophila x virus of drosophila melanogaster are naked icosahedral viruses with an electron microscopic diameter of 58 to 60 nm. the genome of each of these viruses consists of two segments of double-stranded rna (molecular weight range between 2.6 x 10(6) and 2.2 x 10(6), and the virion, capsid proteins fall into three size class categories (large, ...1979228080
infectious bursal disease viral infections. i. complement and virus-neutralizing antibody response following infection of susceptible chickens.complement (c) titers were decreased at 3 days postinfection, and virus-neutralizing (vn) antibody was detectable at 3 or 4 days postinfection in chickens with infectious bursal disease virus (ibdv). clotting times were prolonged in all groups tested during the acute phase of the disease. mortality appeared to be associated with the severity of decrease in c titer. the results suggest that the mortality and many of the clinical signs seen with infectious bursal disease are associated with: 1) a ...1979226056
experimental induction of hemorrhagic-aplastic anemia in chickens. ii. serum protein changes.the serologic response of chickens to infectious bursal disease virus (ibdv) and inclusion body hepatitis virus (ibhv) was analyzed. inoculation at one day old with either ibdv or ibhv significantly (p less than 0.05) reduced levels of serum gamma-globulins at 4 weeks postinoculation. this response was not elicited by inoculation of ibdv together with ibhv. birds with experimentally induced or naturally occurring hemorrhagic anemia syndrome (has) had serum proteins quantitatively and qualitative ...1978219832
a recombinant fowlpox virus that expresses the vp2 antigen of infectious bursal disease virus induces protection against mortality caused by the virus.the coding sequences of vp2 from a virulent strain, 52/70, of infectious bursal disease virus (ibdv) were excised from a cdna clone and inserted into a fowlpox plasmid insertion vector. the resulting plasmid, pibd 1, was used to construct a recombinant fowlpox virus, fpibd 1, which expressed vp 2 as a beta-galactosidase fusion protein. chickens vaccinated with fpibd 1 at 1 and 14 days of age, were challenged at 28 days with either ibdv strain 52/70 or the highly virulent strain cs 89. these chic ...19911659797
immunosuppression induced by infectious bursal disease virus.immunosuppression caused by infectious bursal disease virus (ibdv) is of major interest because of the widespread occurrence of the infection in commercial chickens. infection with ibdv at an early age significantly compromises the humoral and local immune responses of chickens. the cellular immune response is also compromised by apparently to a lesser extent and for a short period. the immunosuppression seems to be a result of direct effect (lysis) of b cells or their precursors. other mechanis ...19911664162
a comparison between the effect of an avian reovirus and infectious bursal disease virus on selected aspects of the immune system of the chicken.reovirus 81-176 was inoculated subcutaneously into day-old specific-pathogen-free leghorns and evaluated for its effects on the immune system over a 3-week period. structural criteria included organ weights of the bursa of fabricius (bf) and spleen (sp), scoring of histological lesions in the bf, sp, and thymus, and hematological analyses of the circulating leukocytes. alterations in the functional capacity of the immune system were measured using the graft-versus-host reaction, the response of ...19863015115
isolation and characterization of attenuated plaque variants of infectious bursal disease virus.attenuated plaque variants were obtained from infectious bursal disease virus adapted to chick embryo cell cultures. the large plaque (lp) clone and the small plaque (sp) clone formed homogeneous plaques about 5 and 1 mm in diameter, respectively. neutralization tests indicated that these clones differed little from their parent strain in antigenicity. sp clones showed a retarded growth rate in chick embryo cell cultures as compared with lp clones. the clones were significantly less pathogenic f ...19902162097
use of infectious bursal disease vaccines in chicks with maternally derived chicks with maternally derived infectious bursal disease (ibd) antibodies were inoculated with ibd oil emulsion vaccine. the vaccine protected at least 85 per cent of the chicks when they were challenged at four weeks old with virulent ibd virus and at least 90 per cent of those challenged at seven weeks of age. there was no benefit in using a combination of the oil emulsion vaccine and a live ibd vaccine.19902164276
differentiation between antibodies to serotypes 1 and 2 infectious bursal disease viruses in chicken sera.the usefulness of the virus neutralization (vn) test, the enzyme-linked immunosorbent assay (elisa), and the agar gel precipitin (agp) test in differentiating antibodies to infectious bursal disease virus serotypes 1 and 2 was investigated. sera examined were from chickens that were challenged with live virus or inoculated with inactivated oil-emulsion ibdv vaccines or were both challenged and inoculated. antibodies to serotypes 1 and 2 were differentiated by the vn test but not by the elisa, an ...19902177971
comparative studies on structural and antigenic properties of two serotypes of infectious bursal disease virus.the electrophoretic mobilities of the two genome segments and the structural polypeptides of the chicken strain cu-1 (serotype i) and the turkey isolate 23/82 (serotype ii) of infectious bursal disease virus were compared. there is a close antigenic relationship between the smaller of the two major structural proteins (32k) of both strains. neutralizing monoclonal antibodies are induced by the larger protein (40k in cu-1) which differentiates between the two serotypes. the 40k structural protein ...19882450966
a conformational immunogen on vp-2 of infectious bursal disease virus that induces virus-neutralizing antibodies that passively protect chickens.vp-2b, a major structural protein of infectious bursal disease virus (ibdv), and its precursor protein vp-2a were separated in a soluble form from the supernatant of ultracentrifuged viruses by using a monoclonal antibody specific for vp-3, the other major structural protein, to remove soluble vp-3 and remaining virus particles. the native vp-2a/2b inhibited the majority of virus-neutralizing (vn) activity in chicken anti-ibdv sera and chickens immunized with vp-2a/2b produced vn antibodies that ...19892543787
pathogenicity of recent isolates of infectious bursal disease virus in specific-pathogen-free chickens: protection conferred by an intermediate vaccine strain.the pathogenicity of recent isolates of infectious bursal disease virus and the protection conferred against them by a commercial vaccine strain of intermediate virulence were examined in specific-pathogen-free chickens. based on clinical signs, mortality, and macroscopic lesions in susceptible chickens, the isolates designated as a-delmarva and u-28 were distinct from a previously known serotype i virulent isolate (edgar). histopathological analysis of the bursa of fabricius did not establish d ...19892559705
comparative tests on safety and potency of iba vaccines.during a comparative test on the pathogenicity and immunogenicity of a non-adapted and an embryo-adapted ida virus, following observations were made: 1) the non-adapted virus remained pathogenic as determined by weight loss and bursal lesions. clinical signs and mortality did not occur. a change in the virulence did not occur during back passages; 2) the immunosuppressive effect of the non-adapted virus was diminished by maternal antibodies; 3) the embryo-adapted virus produced little pathogenic ...1976182590
vaccination against marek's disease and infectious bursal disease iii. growth rate of both turkey herpesvirus and infectious bursal disease virus in coinfected cell cultures.titers of the turkey herpesvirus (hvt) and infectious bursal disease virus (ibdv) in coinfected cell cultures, used to produce a live bivalent hvt/ibdv vaccine, were determined daily. based on the daily titers, cells harvested either 2 or 3 days after inoculating the second virus (ibdv) into hvt infected cell cultures yielded the maximum titers for both viruses. harvesting coinfected cell cultures on either day provided the most suitable source of the live hvt/ibdv vaccine against marek's diseas ...19852987896
detection of antibodies against infectious bursal disease virus: a comparison of three serological methods.four different oil emulsion infectious bursal disease virus (ibdv) vaccines were inoculated into four-week-old specific pathogen-free chickens. at weekly intervals for five weeks, sera were obtained from the vaccinated birds and from uninoculated control birds and examined for antibodies against ibdv by enzyme-linked immunosorbent assay (elisa), the quantitative agar gel precipitin (qagp) test and the virus neutralisation (vn) test. there was a highly significant correlation between the mean res ...19852988091
evaluation of the specificity and sensitivity of two commercial enzyme-linked immunosorbent assay kits, the serum plate agglutination test, and the hemagglutination-inhibition test for antibodies formed in response to mycoplasma gallisepticum.two commercial enzyme-linked immunosorbent assay (elisa) kits, seven serum plate agglutination (spa) antigens, and the hemagglutination-inhibition (hi) test for antibodies to mycoplasma gallisepticum (mg) were compared for sensitivity and specificity using known mg-positive and mg-negative sera from leghorn chickens. all spa antigens proved to be highly sensitive when testing mg-positive sera. laboratory-prepared spa antigens yielded fewer positive reactions when testing mg-negative sera than co ...19883041957
the use in practice of inactivated oil emulsion vaccine against infectious bursal disease in broiler breeders and its influence on the progeny: a comparative field trial.field trials were conducted to establish the effect of the use of an inactivated oil emulsion vaccine against infectious bursal disease (ibd oev) in broiler breeder hens, and its effects on their progeny. the performance of 18 broiler flocks, which were the progeny of the ibd oev vaccinated breeder hens, but which were not vaccinated with a live vaccine against ibd, was equal to that of broiler flocks which were vaccinated with a live ibd vaccine and originated from parent stock that had been va ...19852990089
infectious bursal disease virus: growth and characterization in cell cultures. 19744364080
isolation and identification of infectious bursal disease virus in lebanon. 19744368849
immunogenicity and antigenicity of infectious bursal disease virus serotypes i and ii in chickens.chickens were inoculated with infectious bursal disease virus serotype i or serotype ii to determine if their immune system can distinguish between the two serotypes. chickens had neutralizing antibodies to only serotype i viruses following exposure to serotype i viruses, and chickens had antibodies to only serotype ii viruses following exposure to serotype ii viruses. no cross-reactions were observed between antisera prepared to each of these two serotypes using a cross-virus-neutralization ass ...19853008699
performance of 3 successive generations of specified-pathogenfree chickens maintained as a closed antibodies against salmonella pullorum, mycoplasma gallisepticum, mycoplasma synoviae, haemophilus gallinarum, fowl pox virus, marek's disease virus, herpes virus of turkey, infectious laryngotracheitis virus, avian adenovirus, avian reovirus, infectious bursal disease virus, reticuloendotheliosis virus, avian leukosis virus, avian encephalomyelitis virus and newcastle disease virus were detectable in the sera obtained from these chickens in 3 generations at various ages. antibodies against i ...19806253742
haematological values and changes in blood chemistry in chickens with infectious bursal disease.haematological and blood serum chemical changes were studied in two groups of specific pathogen free chickens infected at five weeks old with different field isolates of infectious bursal disease virus. blood and serum components were determined five days after infection. there were significant decreases (p less than 0.05) in the total erythrocyte count, packed cell volume, haemoglobin concentration, albumin, albumin: globulin ratio, uric acid and glucose. serum components which increased signif ...19863010410
pathogenicity of an isolate of infectious bursal disease virus in local nigerian ducks.three to six-week old local nigerian ducks were inoculated orally and intraocularly with an isolate of infectious bursal disease virus (ibdv) serotype 1 which was pathogenic for chickens. neither clinical signs nor gross or microscopic lesions were observed. ibdv antigen was not detected in the bursa by the agar gel diffusion precipitation test. precipitins and neutralising antibodies to ibdv were also not detected in the serum samples and ibdv was not isolated from the bursa, spleen and liver o ...19902171174
adapting the polymerase chain reaction to a double-stranded rna genome.we have adapted the polymerase chain reaction (pcr) to a double-stranded rna (dsrna) target without possessing unambiguous sequence information. infectious bursal disease virus of chickens, a member of the binavirus group, has a dsrna genome which is resistant to denaturation and subsequent enzyme modification. the only published sequence information was for a strain of virus unavailable to us. we have used a quick primer binding assay to select appropriate primers and have combined a simple den ...19902278387
immune profile of infectious bursal disease: i. effect of infectious bursal disease virus on peripheral blood t and b lymphocytes of chickens.a comparison was made of absolute numbers of peripheral blood b and t lymphocytes, as defined by the anti-bursal and anti-thymus sera, in chickens infected with infectious bursal disease virus at one day and 3 weeks of age by age-matched controls. birds were evaluated sequentially at weekly intervals for a period of 8 weeks postinfection. the severity of depressions of b-lymphocyte numbers was found to be age-dependent: the birds infected at one day of age showed a more severe depletion than tho ...19806255926
immune responses of breeding chickens to trivalent oil emulsion vaccines: responses to infectious bronchitis.three similar flocks of broiler breeder parent chickens that had been given live infections bronchitis (ib) vaccines during rearing were injected at 20 weeks of age with three different oil emulsion vaccines: a commercial monovalent newcastle disease (nd) vaccine (flock a); an experimental bivalent vaccine containing nd and infectious bursal disease (ibd) components (flock b); and an experimental trivalent vaccine containing nd, ibd and ib components (flock c). one week after vaccination 40 hens ...19816266125
pathogenicity studies with a strain of fowl adenovirus serotype 8 (vri-33) in chickens.experiments were undertaken to study the pathogenesis of vri-33, a strain of fowl adenovirus serotype 8 isolated from the liver of a broiler chicken with inclusion body hepatitis. a 30% death rate resulted from oral infection of one-day-old specific pathogen free chickens with 10(6) plaque forming units of vri-33. chickens 10, 14, 21 and 28 days of age did not die following infection via natural routes but there were some motalities following infection via parenteral routes. immunodepression by ...19872838009
antibody to the australian 002-73 strain of infectious bursal disease virus neutralizes and protects against european ibd virus strains. 19882840877
simultaneous application of live turkey herpesvirus and infectious bursal disease vaccines against marek's disease and infectious bursal disease.the efficacy of cell-associated (ca) and cell-free (cf) infectious bursal disease (ibd) vaccines in maternal antibody (mab)-bearing broiler chickens was compared. compatibility and potency of a mixed vaccine combining live ca turkey herpesvirus (hvt) and ca ibd vaccine viruses were also tested against gross lesions induced by marek's disease (md) or ibd in specific-pathogen-free chickens. both ca and cf ibd vaccines provided significant protection against gross bursal lesions of ibd in the prese ...19852983300
replication of infectious bursal disease virus in continuous cell lines.three mammalian continuous cell lines--ma-104, vero, and bgm-70--were tested for their ability to support replication of infectious bursal disease virus (ibdv). selected tissue-culture-adapted vaccine strains and tissue-culture-adapted field isolates of ibdv replicated in the ma-104, vero, and bgm-70 cells; cytopathic effects were most pronounced in the bgm-70 cells. the cytopathic effects of the viruses in bgm-70 cells and chicken embryo fibroblast (cef) cultures were similar. virus-neutralizat ...19873039967
absence of influence on immune competence by the sex-linked gene (k) determining slow feathering in white leghorn chickens.males of white leghorn strain crosses heterozygous (kk) for the sex-linked feathering locus genes were mated to rapid-feathering (k-) females to produce rapid- and slow-feathering chicks of both sexes. k did not influence humoral-mediated immunity against challenge with sheep erythrocytes, killed brucella abortus, or killed infectious bursal disease virus. chicks challenged at 3 weeks of age had higher primary responses and higher titers of 2-mercaptoethanol-resistant antibody (igg) than those c ...19863814012
[electron microscopic research on an experimental infection in chicks caused by the infectious bursal virus].a total of 18 birds at the age of 25 days were infected intraocularly with the pathogenic strain 52/70 of the infectious bursitis virus. the bursa of fabricius and the thymus were sampled for electron-microscopic investigations. the ultrastructural changes in the infected cells consisted in pycnosis of the lymphocyte and macrophage nuclei, vacuolization of the cytoplasm, and the production of lipid droplets as well as of inclusion bodies of varying density, myelin figures, multivericular bodies, ...19853002003
infectious bursal disease immunisation failures in chickens in nigeria. 19863016956
genomic structure of the large rna segment of infectious bursal disease virus.the larger rna segment of infectious bursal disease virus (ibdv: australian strain 002-73) has been characterized by cdna cloning and nucleotide sequence analysis. we believe ibdv is the first birnavirus to be sequenced and so have confirmed the coding region by n-terminal amino acid sequence analysis of intact viral proteins and several tryptic peptide fragments. the large rna segment encodes in order the 37-kda, 28-kda and 32-kda proteins within a continuous open reading frame and the primary ...19863014441
vaccination of day-old broiler chicks against newcastle disease and infectious bursal disease using commercial live and/or inactivated broilers were administered live and/or inactivated vaccines to assess vaccine efficacy against challenge with newcastle disease (nd) and infectious bursal disease (ibd). chicks were from commercial breeder pullets vaccinated against nd and ibd using several live vaccine primers followed by an inactivated nd-ibd vaccine at 18 weeks. the most efficacious initial nd-ibd vaccination program was live nd virus by eye drop and live ibd vaccine injected subcutaneously (sq) followed 2 hours later ...19863021102
quantitation of natural antibodies to infectious bursal disease in nigerian indigenous chickens.serum samples collected from 687 indigenous chickens located in small scattered groups in four states of nigeria were examined for antibodies to infectious bursal disease (ibd) virus by the agar-gel precipitation (agpt) and counterimmunoelectrophoresis (cieop) tests. 51 of the positive samples were further titrated by each of the two techniques. cieop detected more positive reactors (74.59%) than agpt (58.95%). cieop also detected higher antibody levels among the reactors [geometric mean titre ( ...19863021387
[enhanced pathenogicity of chicken anemia agent (caa) in dual infections with marek's disease virus (mdv), infectious bursal disease virus (ibdv) or reticuloendotheliosis virus (rev)]. 19863014789
infectivity of infectious bursal disease virus neutralized by maternal antibody in various chicken cells. 19892548026
infectious bursal disease (ibd) and coccidiosis concurrent infections in nigerian indigenous chickens. a case an outbreak of concurrent infectious bursal disease (ibd) and caecal coccidiosis in a flock of 45 nigerian indigenous chickens comprising of 36 unsexed 29 days old chicks and 9 adult hens, 75 per cent mortality was recorded. the adult hens were not affected.19892562039
comparison of the effect of live newcastle disease vaccine clone 30 in broilers administered at day 1 or at day 7 and the effect of h120 vaccination at 17 days of age: a field analyse the results of a vaccination on the first day of age against newcastle disease (nd) and on the 17th day of age against infectious bronchitis (ib) resp. with spray vaccines with clone 30 and h120 vaccine. these vaccinations are compared in field circumstances with other vaccination methods. a serological examination and challenge test were used to be informed about the response and protection. from the present study the following conclusions can be drawn: clear indications are obtained ...19873031867
lysis of chicken lymphocytes by infectious bursal disease viruses.infectious bursal disease virus types 1 and 2 were able to induce direct lysis of chicken bursal cells, thymus cells, and peripheral blood lymphocytes in chromium-release assays. these two viruses were unable to lyse two established lymphoblastoid cell lines, although ibdv-1 was capable of multiplying in msb-1 cells.19882849407
vaccination against marek's disease and infectious bursal disease. ii. titration and in vivo efficacy of the coinfection-derived bivalent live vaccine for turkey herpesvirus and infectious bursal disease virus.the bivalent hvt/ibdv live vaccine, developed by cocultivation of the turkey herpesvirus (hvt) and infectious bursal disease virus (ibdv) vaccine in cell cultures, was quantitated. the titer of each constituent virus could be successfully determined in vitro by pretreatment of the vaccine with anti-ibdv serum or chloroform (chcl3). studies in vivo further demonstrated that the anti-ibdv serum-treated hvt/ibdv vaccine lost its immunogenicity by failing to induce ibdv-neutralizing antibody or to p ...19846091083
comparison of a kinetic-based enzyme-linked immunosorbent assay (kelisa) and virus-neutralization test for infectious bursal disease virus. ii. decay of maternal antibody in progeny from white leghorns receiving various vaccination regimens.a computer-assisted single-serum-dilution indirect kinetic-based enzyme-linked immunosorbent assay (kelisa) was used for quantitating the natural decay rate of infectious bursal disease virus (ibdv) maternal antibody in progeny obtained from white leghorn breeders. the kelisa results were compared with those of a standard virus-neutralization (vn) test. pullets were subjected to two ibdv immunization regimens. group 1 was vaccinated at weeks 0, 2, and 10 with two live vaccines in drinking water ...19863015098
applications of the polymerase chain reaction to detect infectious bursal disease virus in naturally infected chickens.reverse transcriptase-polymerase chain reaction was used for identification of israeli isolates of infectious bursal disease virus (ibdv). the system was applied to tissue culture and to bursa of fabricius from infected chickens; these latter samples had been frozen for as long as 4 years. from base homology analysis of published sequences of serotype 1 ibdv, two pairs of primers, targeted to amplify sequences from the vp2 and vp3 cistrons, were prepared. the two sets of primers could detect vir ...19947702524
response of mibolerone-treated chickens to infectious bursal disease virus.the response of mibolerone-treated chickens to infectious bursal disease virus (ibdv) was studied. chickens fed a ration containing mibolerone at 1.5 parts per million (ppm) developed bursal atrophy by 4 weeks of age. no indication was found that mibolerone prevented ibdv infection even after 7 weeks of feeding. furthermore, only chickens treated with mibolerone died when infected with ibdv at 2 or 3 weeks of age, and treated chickens had more severe clinical signs than did untreated controls wh ...19806254486
monitoring of highly virulent infectious bursal disease in botswana 1989 to 1993. 19947809988
an indirect enzyme-linked immunosorbent assay (elisa) for measuring antibodies in chickens infected with infectious bursal disease immuno-enzyme assay for measuring infectious bursal disease antibodies in chickens is described. the test is performed rapidly after coating plates overnight with partially purified antigen prepared in cell culture. coated plates can be stored for at last 4 months. the chromatographically purified rabbit anti-chicken immunoglobulin-g, conjugated to horseradish peroxidase, was used optimally at a dilution of 1:3,000. it could be stored for at least 10 months without a reduction in titer. the t ...19806254489
a rapid quantitative agar gel precipitin test. 19836306011
diseases and management of backyard chicken flocks in chitungwiza, gather information on backyard chicken flocks in chitungwiza, an urban center in zimbabwe, 85 flock owners were interviewed. the mean flock size was 53 birds (range 1-650), and most birds were kept for meat, for either domestic consumption or local sale. mean age at slaughter was 12.4 weeks (range 8-24). none of the owners vaccinated their birds, and reported mortality rates were high (mean 25%), most commonly being associated with diseases causing eye and respiratory problems. most owners co ...19947832719
isolation of infectious bronchitis, infectious bursal disease and avian adenoviruses from chickens with nephritis-nephrosis syndrome. 19806255706
direct correlation between the titer of infectious bursal disease virus vp2-specific antibody and protection.the titer of antibody specific to infectious bursal disease virus (ibdv) was measured by a new method and correlated with protection. challenge was carried out in chickens with various antibody titers, which were measured using a latex agglutination-inhibition (li) test, a rapid and easy technique for measuring ibdv vp2-specific antibody. when actively immunized chickens had li titers of 1:2 or more, almost all were protected from subsequent challenge with highly virulent ibdv. in contrast, even ...19947980272
subclinical infectious bursal disease in commercial broiler flocks in saskatchewan.five commercial broiler flocks, not vaccinated for infectious bursal disease virus, derived from infectious bursal disease virus-vaccinated breeder flocks were surveyed for evidence of bursal damage and infectious bursal disease virus infection. they were compared with two groups of birds raised in isolation. serum samples from one day old chicks contained maternal anti-infectious bursal disease virus antibodies which declined to undetectable levels by four weeks of age. serum antibody levels re ...19816268263
an outbreak of infectious bursal disease among chickens between 16 and 20 weeks old.infectious bursal disease (ibd) was diagnosed in a flock of 1,031 broilers and cockerels aged between 16 and 20 weeks. affected birds passed whitish, watery feces. on postmortem examination, the bursa of fabricius (bursa) was enlarged and the kidney tubules were well distended. histopathological sections of the bursa were characterized by edema, destruction of lymphocytes, and heterophilic infiltration. spread was rapid, and the average mortality rate was 3.5%. bursal homogenates from dead chick ...19816279063
comparison of precipitin antibodies and virus-neutralizing antibodies to infectious bursal disease virus.three hundred twenty-two serum samples from commercial pullets and multiplier breeders were analyzed for agar-gel precipitin (agp) antibodies and virus-neutralizing (vn) antibodies to infectious bursal disease virus. two hundred thirty-four of these sera were agp-positive, and 88 were agp-negative. the geometric mean of the reciprocal of the vn titers for the agp-positive sera was 208.7, and 232 (99.1%) had a vn titer of 1:16 or greater. in contrast, the geometric mean of the reciprocal of the v ...19816279066
recovery of virus from feces and tissues of chickens infected with cell-culture-adapted infectious bursal disease virus. 19826287071
a rapid quantitative method for detecting infectious bursal disease virus using polystyrene latex microspheres.a monoclonal antibody (mab) to infectious bursal disease virus (ibdv) was bound to polystyrene latex microspheres. the microspheres agglutinated with extracts of bursae and sera from chickens infected with all strains or isolates of ibdv tested. agglutination appeared within a 10-min reaction time. the assay could detect a 10(3.7) to 10(4.5) mean embryo infective dose (eid50) of the virus in 0.01 ml and the titer of the assay was 10- to 40-times higher than that of the agar gel precipitin test.19938395538
field trials with an oil emulsion infectious bursal disease vaccine in broiler breeder pullets.two independent field trials were undertaken with commercial broiler companies in separate sections of alabama in order to test the efficacy of an experimental commercially prepared oil emulsion infectious bursal disease (ibd) vaccine in broiler breeder pullets. the ibd vaccine was tested both for safety and the production of neutralizing antibodies in pullets and their progeny as well as its ability to prevent early field exposure to virulent ibd virus (ibdv) in broiler progeny that may lead to ...19826291020
lesions induced in the respiratory tract of chickens by serologically different adenoviruses.ten strains of adenovirus representing 10 serotypes were administered intratracheally to two groups of 3-week-old specific-pathogen-free chickens. birds in group 1 were given only adenovirus. birds in group 2 were inoculated with a virulent infectious bursal disease virus (ibdv) by eye-drop at one day of age as well as with the adenovirus at 3 weeks. the chicks were examined daily. respiratory rales were observed in some birds with the dual infection. gross pathologic alterations were minimal an ...19826293441
field test studies of the 2512 strain of infectious bursal disease.responses to an infectious bursal disease vaccine made from the 2512 strain were studied in broiler flocks under field conditions and management. pre- and post-vaccination sera were analyzed by agar-gel-precipitin tests and beta virus neutralization. specific measurements of broiler performance (livability, weight, feed conversion, and condemnations) were also analyzed. when possible, contemporary licensed products were compared at the same time in adjacent houses. results of these trials indica ...19826297449
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