Publications
| Title | Abstract | Year(sorted ascending) Filter | PMID Filter |
|---|
| binding of the pathogen receptor hsp90aa1 to avibirnavirus vp2 induces autophagy by inactivating the akt-mtor pathway. | autophagy is an essential component of host innate and adaptive immunity. viruses have developed diverse strategies for evading or utilizing autophagy for survival. the response of the autophagy pathways to virus invasion is poorly documented. here, we report on the induction of autophagy initiated by the pathogen receptor hsp90aa1 (heat shock protein 90 kda α [cytosolic], class a member 1) via the akt-mtor (mechanistic target of rapamycin)-dependent pathway. transmission electron microscopy and ... | 0 | 25714412 |
| infectivity of infectious bursal disease virus for embryonating eggs. | 1970 | 4989111 | |
| identification of the infectious bursal disease virus in mexico. | 1972 | 4622733 | |
| infectivity and distribution of infectious bursal disease virus in the chicken. persistence of the virus and lesions. | 1972 | 4624935 | |
| infectious bursal disease viral particles revealed in avian cell culture by electron microscope. | 1973 | 4376189 | |
| isolation of infectious bursal disease virus and distribution of precipitating antibodies in chicken sera. | 1973 | 4200133 | |
| biological and physico-chemical properties of the infectious bursal disease virus (ibdv). | some biological properties of an egg-adapted strain of ibdv, pv1, have been studied. by immunofluorescent staining the strain is serologically identical to another egg-adapted strain, mu2, and to three pathogenic strains of ibdv. all five strains do not react with antisera prepared against known avian viruses of various groups, including reoviruses. the egg-adapted strain pv1 replicates in chick embryo fibro-blasts and in rk13 cells, with the formation of plaques. the pv1 strain, highly neuropat ... | 1973 | 18777392 |
| attenuation of infectious bursal disease virus and vaccination trials under laboratory and field conditions. | adaptation to the chicken embryo of a virus strain of infectious bursal disease resulted in a reduction in virulence. after 60 passages the strain was attenuated enough to be used as a vaccine. the attenuation proved adequately stable. if given orally in the drinking water, the strain induced the development of neutralising and precipiting antibodies and a strong resistance against the disease. promising results have also been obtained in the field. | 1974 | 18777257 |
| some properties of precipitating antigens associated with infectious bursal disease virus. | infection of the bursa of fabricius and chicken embryo fibroblast cell cultures with avian infectious bursal disease virus resulted in production of a number of virus-induced antigens. the antigens were specific, forming three precipitin lines by immunodiffusion with antiserum (designated pa-1, -2, and -3). to separate immunoprecipitin from the remaining viral particles, two (pa-1 and pa-3) were partially purified by subjection to two cycles of diethylaminoethyl-cellulose chromatography and filt ... | 1974 | 4215758 |
| the immunodepressive effect of infectious bursal disease virus in chickens. | 1974 | 4360708 | |
| infectious bursal disease virus: growth and characterization in cell cultures. | 1974 | 4364080 | |
| isolation and identification of infectious bursal disease virus in lebanon. | 1974 | 4368849 | |
| the occurrence of cytopathic effect of an isolate of infectious bursal disease virus. | 1974 | 4449163 | |
| electron-microscope characterization of infectious bursal disease virus. | 1974 | 4851821 | |
| structure of infectious bursal disease virus. | infectious bursal disease virus of chickens was purified, and its structure was examined by the negative-staining technique in the electron microscope. the buoyant density of infectious bursal disease virus in cscl was found to be 1.34 g/cm(3). the morphological details suggest that the capsid of the virion consists of a single layer of 32 capsomeres arranged in 5:3:2 symmetry. the virion measured about 55 nm in diameter and had no envelope. | 1974 | 4138194 |
| infectious bursal disease agent: morphology by negative stain electron microscopy. | the virus of infectious bursal disease of chickens was studied by immune electron microscopy. negatively-stained preparations revealed morphological similarities with both the bluetongue virus group, and the virus of infectious pancreatic necrosis of trout. results indicated that the small particle found in such preparations is a degradation product of the large particle. | 1975 | 50057 |
| infectious bursal disease virus: antigen production and immunity. | 1975 | 164798 | |
| a comparison of gel diffusion, fluorescent antibody and virus isolation methods in experimental and natural cases of infectious bursal disease. | in studies with chicks inoculated with the sk-1 strain of infectious bursal agent the bursa of fabricius was found to be the tissue of choice for virus isolation as well as for use in the fluorescent antibody test and the agar gel diffusion test. in separate experiments positive results were obtained until postinoculation days 3 or 4 by the agar gel diffusion test, 5 or 6 by the fluorescent antibody test and 14 by the virus isolation method, respectively. bursas from chickens involved in seven n ... | 1975 | 164991 |
| immunodeficiency in the chicken. ii. production of monomeric igm following testosterone treatment or infection with gumboro disease. | chickens were treated at an early embryonal age with testosterone propionate or infected neonatally with the virus producing gumboro disease. their sera were subsequently fractionated by sephadex g-200 chromatography, and showed a complete deficiency of igg and the presence of igm which was eluted with the 7s protein fraction. purified and 125-i-labelled monomeric igm was examined by sds-acrylamide gel electrophoresis and found to contain both mu and light chains, together with a chain of interm ... | 1975 | 166037 |
| the effect of diet on the severity of losses from infectious bursal disease (gumboro) in a commercial broiler genetype. | a natural outbreak of infectious bursal disease occurred in an experimental broiler flock being reared on 3 starter diets having 18.8, 21.6 and 24.0 per cent protein. groups fed the highest protein starter exhibited significantly higher mortality and had larger numbers of stunted birds. | 1975 | 166366 |
| 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 ... | 1975 | 170888 |
| comparison of vaccines against infectious bursal disease. | 1975 | 171288 | |
| letter: quantitation of antibodies to infectious bursal disease. | 1975 | 171823 | |
| the roles of the infectious bursal agent and several avian adenoviruses in the hemorrhagic-aplastic-anemia syndrome and gangrenous dermatitis. | the effect that breeder-flock immune status regarding the infectious bursal agent (iba) and two avian adenoviruses (dpi-1 and dpi-2) has on the susceptibility of their commercially reared delmarva broiler progeny to the hemorrhagic-aplastic-anemia syndrome and concurrent gangrenous dermatitis was determined. lack of immunity to the iba in breeder flocks was related to an increased susceptibility of progeny to anemia and dermatitis. breeder-flock immunity to the two adenoviruses tested could not ... | 1975 | 173278 |
| an outbreak of infectious bursal disease (ibd) of chickens in nigeria. | 1975 | 175539 | |
| purification and preliminary characterisation of a pathogenic strain of infectious bursal disease virus. | a pathogenic strain of infectious bursal disease virus has been purified by density gradient centrifugation, principally on sucrose and tartrate gradients. examination of gradient peak fractions by electron microscopy has revealed two populations of particles of average size 62 nm and 20 nm, which band together on sucrose and tartrate gradients. purified virus has been shown to reproduce the typical symptoms and lesions of infectious bursal disease. the possible classification of the larger viru ... | 1975 | 18777306 |
| specific b lymphocyte suppression by infectious bursal agent (gumboro disease virus) in chickens. | chickens infected experimentally with infectious bursal agent (iba) during embryonation or early after hatching show a severe depression of bursa-dependent lymphoid components, and associated immune functions. data presented here and elsewhere show that the degree of b cell suppression correlates with the time of infection. this would be compatible with a virus-induced block in b lymphocyte differentiation. accordingly, the virus may be cytopathic for early (bursal) but not late (circulating) b ... | 1975 | 11993333 |
| infectious bursal disease in ghana. | 1976 | 16300347 | |
| [infectious bursal disease: distribution and persistence of the virus in inoculated chickens. study on the transmission of the disease]. | the distribution, concentration and persistence of infectious bursal disease virus (ibdv) in the lymphoid organs of inoculated chickens, and its persistence in contaminated premises was examined. the virus only multiplied in the bursa of fabricius where it induced degeneration and necrosis of the lymphoid cells. it persisted for 10 days in this organ and the highest viral concentrations were observed between the 4th and 8th day following inoculation. the virus was found at a low concentration in ... | 1976 | 18777327 |
| 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 ... | 1976 | 176463 |
| 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 ... | 1976 | 177236 |
| [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 ... | 1976 | 179162 |
| 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 ... | 1976 | 182590 |
| infectious bursal disease vaccine: some remarks on production and control. | a vaccine against infectious bursal disease (ibd) is prepared with a strain of ibd virus attenuated in chicken embryos. safety and potency tests are carried out on embryos and chickens susceptible to ibd virus. | 1976 | 182591 |
| standard requirements for vaccines against infectious bursal disease. | a variety of criteria must be considered when examining the suitability of preparations of live infectious bursal disease (ibd) virus for use as vaccines: identity and purity of the vaccine strain, lack of spread, or of tendency to revert to virulence, lack of immunosuppressive effect, safety and potency. arguments as to th identity of ibd virus are well documented, and after ensuring that the virus strain is in fact ibd virus, it must be ascertained that it is free from contaminating agents. ... | 1976 | 182592 |
| the epizootiology of infectious bursal disease and prevention of it by immunization. | transport of leftover feed from infectious disease (ibd) farms to susceptible flocks on clean premises is believed to have played an important role in the transmission of this disease to new farms and to new areas. servicemen, caretakers, contaminated equipment and air were suspected in the spread of the disease, but these modes were not demonstrated. litter, drinking water and samples of feed from feeders of ibd flocks were found to be infectious when added to rations of susceptible chickens b ... | 1976 | 182593 |
| role of the bursa of fabricius in the pathogenicity of inclusion body hepatitis and infectious bursal disease viruses. | chickens were chemically bursectomized with cyclophosphamide at 3 days old, and studies made of the effects of infection by inclusion body hepatitis virus (ibhv) and infectious bursal disease virus. in another experiment, 3-week-old chickens were infected with infectious bursal disease virus before inoculation with ibhv. interference with the bursa of fabricius by cyclophosphamide or by infectious bursal disease virus enhanced the pathogenicity of ibhv. in contrast, cyclophosphamide effects on t ... | 1976 | 183647 |
| 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 ... | 1976 | 183649 |
| effect of infectious bursal agent on the response of chickens to newcastle disease and marek's disease vaccination. | white leghorn chickens raised from one day old in an environment contaminated by the infectious bursal agent (iba) had lower geometric mean titers (gmt) as measured by the hemagglutination-inhibition (hi) test to the newcastle disease virus (ndv), than control leghorns reared in an uncontaminated environment. immunosuppression, defined as a reduction in gmt, was most pronounced at 35-56 days old for leghorns vaccinated with ndv at 1 and 28 days or at 28 days. in a separate trial with broilers, i ... | 1976 | 183651 |
| immunization of adult hens against infectious bursal disease virus. | 1976 | 183653 | |
| infectious bursal disease of chickens and vaccination. | 1976 | 185779 | |
| demonstration of eimeria tenella in bursa of fabricius of chickens. | coccidial life-cytle stages were detected in the bursa of fabricius of broiler chickens inoculated with eimeria tenella, whether or not the chickens had previously been infected with infectious bursal disease virus (ibdv). chickens infected only with e. tenella had developing parasites in the lining epithelium, whereas chickens with both infections had gametocytes also in the epithelial cells surrounding numerous degenerating bursal cysts. | 1976 | 186013 |
| 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. | 1976 | 186932 |
| response of growing chickens to an inactivated ibd antigen in oil emulsion. | 1976 | 188221 | |
| immunosuppressive effects of the infectious bursal agent and relationships to other poultry diseases. | 1976 | 220631 | |
| gumboro disease and infectious bronchitis. | 1977 | 190759 | |
| effect of infectious bursal disease on the response of chickens to mycoplasma synoviae, newcastle disease virus, and infectious bronchitis virus. | at 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 ... | 1977 | 190926 |
| [aplastic anemia, liver necrosis and hemorrhage in chickens after neonatal infection with infectious bursal agent]. | 1977 | 192533 | |
| plaque reduction neutralization test for the serodiagnosis of infectious bursal disease. | 1977 | 192932 | |
| the immunodepressive effect of infectious bursal agent on vaccination against newcastle disease. | immunodepression due to an infectious bursal agent (iba) infection depends on the age of the birds, the time of newcastle disease (nd) vaccination and the iba strain used. the immunodepressive effect of iba on nd vaccination can be avoided by vaccinating the chicks against nd at day old or by using attenuated strains of iba in all commercial vaccines. | 1977 | 193172 |
| specific suppression of the bursa-dependent immune system of chicks with infectious bursal disease virus. | chicks which had been inoculated with infectious bursal disease virus (ibdv) at 1 day of age had a severe depression of bursa-dependent humoral immune functions by day 42. antibody responses against rabbit red blood cells or to immunization with bovine serum albumin were significantly suppressed. in contrast, chicks inoculated with ibdv at 21 days of age produced near normal antibody responses as compared with the responses in noninfected control chicks. the ibdv had no significant effect on the ... | 1977 | 195492 |
| [pathomorphology of infectious bursitis in chicks]. | morphologic studies were carried out on birds aged 17 to 90 days, affected with gumboro disease and occasionally died from the same disease (infectious bursitis). established were hemorrhages in the leg and breast musculature, substantial enlargement of the bursa of fabricius, and lesions in the kidneys. in some cases hemorrhages were also found on the serous membrane of the parenchymal organs. the histologic investigation of the involved parenchymal organs revealed necrobiotic changes (karyopyc ... | 1977 | 201083 |
| [infectious bursitis in switzerland: seroepizootologic studies using counterimmunoelectrophoresis]. | 1977 | 202021 | |
| 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 ... | 1977 | 203907 |
| effect of infectious bursal disease virus on the immunological responsiveness of the chicken. | the immunological response of chickens infected at 28 days of age with infectious bursal disease virus (ibdv) was examined. cellular immunity was studied by the graft-versus-host reaction and delayed type hypersensitivity skin reactions to tuberculin. antibody responses to sheep red blood cells (s-rbc's) were tested by a direct hemagglutination test. circulating levels of immunoglobulins (ig's) igm, igg and iga were monitored by the radial immunodiffusion test. the results of the graft-versus-ho ... | 1977 | 203923 |
| 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 ... | 1977 | 204282 |
| lack of effect of vaccination with an attenuated infectious bursal disease virus on the immune response to newcastle disease vaccination. | vaccination at either 1, 7 or 15 days of age with an attenuated strain (vaccinal strain 1-65 pv) of infectious bursal disease (ibd) virus did not suppress the immune response to newcastle disease vaccination. these results suggest that vaccination of chickens against ibd with vaccinal strain 1-65 pv does not damage the bird's lymphoid tissues and consequently its immunological capabilities against other infectious diseases. | 1977 | 18770306 |
| serological studies on flocks showing depressed egg production. | a serological investigation was undertaken of flocks with depressed egg production. no obvious correlation was found between antibody to adenovirus, infectious bronchitis virus or infectious bursal disease virus and this syndrome. no antibody was detected to newcastle disease virus, mycoplasma gallisepticum or in most cases to mycoplasma synoviae. a relationship was found between the development of antibody to a haemagglutinating virus, 127, and depressed egg production. a retrospective survey o ... | 1977 | 18770349 |
| 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 ... | 1978 | 205149 |
| response to several avian respiratory viruses as affected by infectious bursal disease virus. | after being inoculated with the infectious bursal disease virus (ibdv) at one day of age, specific-pathogen-free chickens were inoculated with either newcastle disease virus (ndv), infectious bronchitis virus (ibv), or infectious laryngotracheitis virus (iltv). their immunity was challenged 2-3 weeks later with homologous virus, and antibody titers were determined for iltv and ibv. several studies were made to determine the effects of ibdv on the development of persistent or chronic virus infect ... | 1978 | 206256 |
| transmission of immunity from inactivated infectious bursal disease oil-emulsion vaccinated parent chickens to their chicks. | 1978 | 207009 | |
| serological evidence of infection with the virus of infectious bursal disease in wild and domestic birds in nigeria. | 1978 | 207012 | |
| vaccination against infectious bronchitis and the immunosuppressive effects of infectious bursal disease. | an immunosuppressive effect was demonstrated in chickens which were infected with infectious bursal disease virus (ibdv) early in life and prior to or shortly after vaccination with infectious bronchitis virus (ibv). this effect was evident by an increased susceptibility to respiratory tract infection with ibv and reduced virus-serum neutralizing antibody levels. chickens which were hatched from dams susceptible to infectious bursal disease (ibd) were less responsive to ibv immunization attempts ... | 1978 | 209433 |
| 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 ... | 1978 | 210556 |
| broiler-breeder vaccination against infectious bursal disease and persistence of maternal antibody in progeny. | 1978 | 210922 | |
| [attenuation of infectious bursal disease virus by serial passage through chicken embryonated eggs and chicken and duck embryonic fibroblasts (author's transl)]. | 1978 | 211726 | |
| interaction of aflatoxin with infectious bursal disease virus infection in young chickens. | young white leghorn chickens fed 2.5 microgram of aflatoxin (afl) per g of diet from hatching until 4 weeks old and infected with infectious bursal disease virus (ibdv) at 3 weeks old had significantly higher mortality and more severely depressed body weights than chicks with aflatoxicosis or ibd alone. afl-ibdv chicks also had more extensive gross and microscopic changes characteristic of ibd than did ibdv-chicks. none of the treatments significantly reduced antibody responses to newcastle dise ... | 1978 | 212001 |
| experimental infection of turkeys with infectious bursal disease virus. | commercial turkey poults 3 to 6 weeks old were infected experimentally by eyedrop with an infectious bursal disease virus (ibdv) inoculum obtained from chickens experiencing clinical ibd. the ibdv was passed 6 successive times in poults in an attempt to increase its pathogenicity for turkeys. regardless of passage level, the ibdv infection in poults was subclinical, with no morbidity, mortality, or gross lesions observed. the bursae of fabricius from infected poults, however, displayed various d ... | 1978 | 212003 |
| rhinotracheitis in turkey poults. | a severe upper respiratory disease of young turkeys is described that resulted in high morbidity and mortality. death was due to asphyxiation produced by occlusion of the trachea or nostrils. the postmortem lesions were tracheitis, pulmonary edema, swollen livers and spleens, and a drastic reduction in bursa size. bursal necrosis and loss of tracheal epithelium were found in tissue sections from clinically affected birds. antibody to infectious bursal disease was found by agar-gel precipitin and ... | 1978 | 212006 |
| interaction between infectious bursal disease virus and newcastle disease virus in chickens. | the australian strain of infectious bursal disease virus (ibdv), 002/73, affected the response of chickens to newcastle disease virus (ndv). the titre of serum antibodies to ndv in chickens infected with ibdv was significantly lower than that of birds infected with ndv alone. it also appeared that ibdv affected ndv excretion from chickens as ndv was more frequently isolated from chickens infected with ibdv, ibdv infection did not alter the pathogenicity of ndv in chickens. this australian strain ... | 1978 | 213047 |
| woodrige memorial lecture. the veterinary profession and an intensive poultry industry. | 1978 | 213871 | |
| susceptibility of chicks to infectious bursal disease (ibd) following vaccination of their parents with live ibd vaccine. | vaccination of parent chickens with a commercial live infectious bursal disease (ibd) vaccine under field conditions at varying ages and by different routes resulted in variable susceptibility to the disease in their chicks. there was little correlation between the methods of vaccination and the levels of immunity in the chicks. there was some evidence that levels of transferred immunity decreased with the age of the parents. of five flocks examined, the onset of susceptibility to ibd occurred a ... | 1978 | 213872 |
| [clinico-epizootologic studies in gumboro disease]. | the disease was established on a poultry dressing combine, affecting birds at the age of three to eleven weeks. it ran its course with clinical symptoms and epizootiology that were characteristic of it. a total of 8778 birds or 10% succumbed to the disease. its notification on a newly built poultry dressing combine made it reasonable to believe that possibility existed of its transmission through the hatcheries. the outbreak occurred almost simultaneously with the inadequate feeding that was adm ... | 1978 | 214935 |
| computer simulation of gumboro disease outbreak. i. construction of models g-1 and g-2. | 1978 | 216928 | |
| prevalence of precipitating antibodies against mycoplasmas and viruses in egg-laying flocks in northern jutland. | antibodies against infectious laryngotracheitis virus, influenavirus and newcastle disease virus were not demonstrated. the prevalence of infections caused by adeno- and reovirus in egg-laying flocks was 85 and 74% respectively. approximately 25% of the flocks had antibodies against infectious bronchitis virus and infectious bursal disease virus. a raised prevalence of antibodies against mycoplasmas was found with increasing age. | 1978 | 643540 |
| virus-neutralization versus agar-gel precipitin tests for detecting serological response to infectious bursal disease virus. | the virus-neutralization (vn) test was found much more sensitive than the agar-gel precipitin (agp) test for detecting prior exposure to infectious bursal disease (ibd). many sera that were negative in the agp test were found to have vn antibodies, and virtually all sera in a commercial flock were free of precipitin but had vn titers. vn titers varied widely on a flock basis, and revaccination of an 8-month-old flock through the drinking water did not alter the antibody titers. inoculation of ma ... | 1978 | 219827 |
| infectious bursal disease virus infection attempts in turkeys and coturnix quail. | attempts failed to infect coturnix quail with infectious bursal disease (ibd) virus by exposure at 7, 14, 21, and 31 days old. there were no clinical signs or gross and microscopic changes in the bursa of fabricius, and serologic tests and virus isolation attempts from cloacal swabs were negative. turkeys of two breeds exposed to ibd virus at 6 or 8 weeks old showed no clinical signs or lesions in the bursa of fabricius, and the virus could not be isolated from cloacal swabs. they did respond se ... | 1978 | 219828 |
| experimental induction of hemorrhagic-aplastic anemia in chickens. i. etiology. | exposure to infectious bursal disease virus (ibdv) at 1 day old followed by inclusion body hepatitis virus (ibhv) inoculation at 36 days produced typical lesions of hemorrhagic-aplastic anemia syndrome (has). the lesions included severe anemia, widespread hemorrhages, and dermatitis. has could not be induced in the first 4 weeks of life in chickens inoculated at one day old with ibhv alone or in combination with ibdv. it was concluded that the immunosuppressive effects of ibdv failed to alter th ... | 1978 | 219831 |
| 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 ... | 1978 | 219832 |
| immune response and pathogenicity of different strains of infectious bursal disease virus applied as vaccines. | eight strains of infectious bursal disease virus (ibdv) were characterized by the criteria of immunity and pathogenicity engendered in young chickens. some strains have been used commercially, and the others are potential candidates for vaccines. they were administered by drinking water, eyedrop, vent drop, and subcutaneous and aerosol routes. the viruses varied widely in pathogenicity in terms of bursal damage, morbidity, and mortality. immunity induced with different routes of administration a ... | 1978 | 219835 |
| 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 ... | 1979 | 219952 |
| loss of virulence in a small plaque mutant of the infectious bursal disease virus. | a variant strain cu-1 m was established from the infectious bursal disease virus strain cu-1. this variant strain forms smaller plaques than the wild type; it has a retarded growth rate, does not lead to an overt disease in chickens and causes only minor lesions in the bursa of fabricius. infection with this strain induces solid protective immunity against infection with the virulent virus. | 1979 | 218535 |
| the use of an inactivated infectious bursal disease oil emulsion vaccine in commercial broiler parent chickens. | 1979 | 222040 | |
| comparison of two infectious bursal disease vaccine strains: efficacy and potential hazards in susceptible and maternally immune birds. | two infectious bursal disease vaccines were administered to separate groups of maternally immune and susceptible chickens at various ages. vaccine b caused no damage to the bursae of chickens examined histologically at nine and 20 days after vaccination. the bursae of chickens given vaccine a were shown to be severely damaged when similarly examined. both vaccines protected all the susceptible groups against challenge, but only vaccine a protected the groups of maternally immune chickens. suscep ... | 1979 | 224563 |
| standardization of the quantitative agar gel precipitin test for antibodies to infectious bursal disease. | 1979 | 225328 | |
| 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 ... | 1979 | 226048 |
| growth of infectious bursal disease virus with plaque formation in chick embryo fibroblast cell culture. | the wa69 isolant of infectious bursal disease virus (ibdv) induced cytopathic effects and plaque formation in chick embryo fibroblast (cef) cultures after serial passages in embryonated eggs and then in cef cultures. the plaque-forming agent was cloned (designated wa69 clone) and identified as ibdv on the basis of serologic response in inoculated birds and its antigenic relationship to other known ibdv isolants. the wa69 clone replicated rapidly in cef cultures, reaching peak titers at 48 hours ... | 1979 | 226052 |
| immune-complex involvement in the pathogenesis of infectious bursal disease virus in chickens. | frozen kidney sections from chickens inoculated with infectious bursal disease virus (ibdv) were stained with fluorescein-conjugated rabbit anti-chicken gamma-globulin. fluorescence was observed in the renal glomeruli of infected chickens, indicating that gamma-globulins, probably in the form of immune complexes, had lodged in the glomeruli of ibdv-infected chickens. this suggests that immune complexes may play an important role in the pathogenesis of ibdv infections in chickens. | 1979 | 226053 |
| an infectious bursal disease virus outbreak in 14- and 15-week-old chickens. | infectious bursal disease virus (ibdv) observed in a flock of 14- and 15-week-old chickens was typical of the acute symptomatic ibdv infections more common in younger birds. high flock morbidity was indicated by a marked decrease in feed consumption, although deaths were not excessive. at necropsy, affected birds had small hemorrhages in thigh muscles, creamy-yellow-colored bursae of fabricius with prominent longitudinal striations, and swollen mottled kidneys. histopathologic examination reveal ... | 1979 | 226055 |
| 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 ... | 1979 | 226056 |
| 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 ... | 1979 | 226946 |
| in vitro replication of infectious bursal disease virus in established lymphoid cell lines and chicken b lymphocytes. | the in vitro susceptibility of chicken lymphocytes to a wild strains of infectious bursal disease virus was investigated by using immunofluorescence and virus assays as infection criteria. a variety of marek's disease lymphoblastoid cell lines, all of thymus (t-cell) origin, were refractory to virus exposure. however, a bursa (b-cell)-derived lymphoblastoid cell line from an avian leukosis virus-induced tumor was highly susceptible. viral antigen appeared in the cytoplasm of 20 to 30% of the cel ... | 1979 | 227789 |
| 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, ... | 1979 | 228080 |
| biochemical studies with infectious bursal disease virus: comparison of some of its properties with infectious pancreatic necrosis virus. | infectious bursal disease (ibd) virus was purified from the bursae of infected chickens. two morphologically indistinguishable populations of virus particles were separated in sucrose gradients and possessed sedimentation coefficients of 295s and 460s. both populations contained rna and had identical polypeptide compositions. ibd virus banded at a density of 1.31 g/ml in cscl and at 1.24 g/ml in sodium potassium tartrate. ibd virus contained two rna segments with mol. wts. of 2.4x10(6) and 2.2x1 ... | 1979 | 228637 |
| the genome of infectious bursal disease virus consists of two segments of double-stranded rna. | the rna of infectious bursal disease virus was reexamined in a detailed analysis. it could be established that its genome consists of two segments of double-stranded rna. the rna is rnase resistant and has a sedimentation coefficient of 14s and a buoyant density of 1.62 g/ml. the purine/pyrimidine ratio is nearly 1; the guanine plus cytosine content is 55.3%; the tm is 95.5 degrees c. the molecular weights of the two double-stranded segments were determined to be 2.2 x 10(6) and 2.5 x 10(6). | 1979 | 229240 |
| peptide map comparison of the proteins of infectious bursal disease virus. | the genome of infectious bursal disease virus consists of two segments of double-stranded rna of 2.5 x 10(6) and 2.2 x 10(6) molecular weight. polyacrylamide gel electrophoresis of purified virus resolved four structural polypeptides: vp-1 (90,000), vp-2 (41,000), vp-3 (35,000), and vp-4 (28,000). peptide map comparisons of radioiodinated virion proteins indicated no precursor-product relationship between them. the possible relationship between the size of the virus genome and the number and siz ... | 1979 | 229260 |
| measurement of immunosuppression in chickens caused by infectious bursal disease vaccines using brucella abortus strain 19. | the serological response of chicks to brucella abortus strain 19 was monitored over a period of seven weeks to assess the degree of immunosuppression caused by vaccination at one day of age with two infectious bursal disease vaccines. one of the vacy. this vaccine caused severe immunosuppression judged by the minimal serological response following b abortus inoculation. the test also detected a significant delay caused by the other vaccine in the development of the serological response but the m ... | 1979 | 230558 |
| 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 ... | 1979 | 230768 |
| 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 ... | 1979 | 230805 |
| immunofluorescent studies of early virus propagation after oral infection with infectious bursal disease virus (ibdv). | 1979 | 231357 |