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
molecular detection of infectious bursal disease virus by polymerase chain reaction.the polymerase chain reaction (pcr) technique was applied to the detection of infectious bursal disease virus (ibdv). reverse transcription followed by the pcr was used to amplify a portion of ibdv genome. a set of primers that specify a 150-base-pair segment of ibdv genome was chosen from an australian strain of ibdv. standard challenge strain and variant strains a, d, e, g, and gls-5 of ibdv serotype 1 and oh strain of serotype 2 from infected bursae were subjected to reverse transcription, fo ...19921320861
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
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
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
serological survey of the incidence of infectious bursal disease serotypes 1 and 2 in chicken and turkey flocks in england. 19853000053
histopathologic changes induced by serotype ii infectious bursal disease virus in specific-pathogen-free chickens.specific-pathogen-free (spf) chickens were infected with infectious bursal disease virus (ibdv) serotype ii (turkey, missouri isolate) at 1 day or 4 weeks of age. chickens infected at 1 day had small bursas 3 weeks postinfection (pi). bursas were necrotic and inflamed through 1 week pi. post-necrotic atrophy of the bursas was marked at 3 weeks pi, and plasma cells in the harderian gland were depleted. chickens infected at 4 weeks had slightly enlarged spleens with small gray foci on the surface ...19863028355
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
herpesvirus of turkey recombinant viruses expressing infectious bursal disease virus (ibdv) vp2 immunogen induce protection against an ibdv virulent challenge in chickens.two recombinant herpesviruses of turkey (hvt) expressing the vp2 protein of infectious bursal disease virus (ibdv or gumboro disease virus) have been constructed: vhvt001 and vhvt002. the vp2 open reading frame was inserted at the locus of the small subunit of ribonucleotide reductase gene (hsv-1 ul40 homolog) without any exogenous promoter in vhvt001 and at the locus of gl gene (hsv-1 us7 homolog) under the control of the human cytomegalovirus immediate-early promoter in vhvt002. the isolation ...19957645252
differential detection of turkey coronavirus, infectious bronchitis virus, and bovine coronavirus by a multiplex polymerase chain reaction.the objective of the present study was to develop a multiplex polymerase chain reaction (pcr) method for differential detection of turkey coronavirus (tcov), infectious bronchitis coronavirus (ibv), and bovine coronavirus (bcov). primers were designed from conserved or variable regions of nucleocapsid (n) or spike (s) protein gene among tcov, ibv, and bcov and used in the same pcr reaction. reverse transcription followed by the pcr reaction was used to amplify a portion of n or s gene of the cor ...200616137773
full genome sequence and some biological properties of reticuloendotheliosis virus strain apc-566 isolated from endangered attwater's prairie chickens.reticuloendotheliosis virus (rev) causes runting, high mortality, immunosuppression, and chronic neoplasia associated with t and/or b cell lymphomas in a variety of domestic and wild birds, including attwater's prairie chickens (apc) (tympanuchus cupido attwateri). the complete proviral sequence of a recent rev isolate from apc (rev apc-566) was determined. this virus was isolated from an apc maintained in captivity in a reproduction program intended to avoid its extinction. rev apc-566 was dete ...200717098316
a recombinant turkey herpesvirus expressing chicken interleukin-2 increases the protection provided by in ovo vaccination with infectious bursal disease and infectious bronchitis ovo vaccination remains an attractive option for the mass application of vaccines to poultry, ensuring a uniform application of vaccine in a cost-effective manner. however, the number of vaccines that can be delivered safely by this method is limited. several infectious bursal disease virus (ibdv) vaccines can be given in ovo though most are delivered post-hatch and there are no currently licensed embryo-safe infectious bronchitis virus (ibv) vaccines. reduction in the dose of vaccines given ...200717996994
comparative susceptibility of chickens, turkeys and ducks to infectious bursal disease virus using immunohistochemistry.twenty chicks, 12 turkey poults and 10 ducklings, all 5 weeks old were infected with 2 x 10(3.5) chick ld(50) ibd virus to determine the course of the virus in the 3 poultry species. uninfected control birds were kept separately. two infected and 2 control birds/species were euthanized at time intervals between 3 and 168 hours post infection (pi). sections of thymus, bursa of fabricius, spleen, liver, kidney, proventriculus and ceacal tonsil were stained for the detection of ibd virus antigen us ...200918663594
isolation and characterization of a very virulent infectious bursal disease virus from turkey.infectious bursal disease (ibd) is a highly contagious disease of chickens caused by infectious bursal disease virus (ibdv). in turkeys, however, infection with classical virulent ibdv strains lead only to subclinical forms of the disease. we attempted to isolate ibdv from the bursa of turkey and characterize it. amplification of a 743-bp fragment of vp2 gene by rt-pcr and restriction analysis of the product showed a pattern compatible with very virulent ibdv (vvibdv). comparison of the sequence ...200919941391
development, standardization and assessment of pcr systems for purity testing of avian viral vaccines.the european pharmacopoeia (ph. eur.) requires avian viral vaccines to be free of adventitious agents. purity testing is an essential quality requirement of immunological veterinary medicinal products (ivmps) and testing for extraneous agents includes monitoring for many different viruses. conventional virus detection methods include serology or virus culture, however, molecular tests have become a valid alternative testing method. nucleic acid testing (nat) is fast, highly sensitive and has a h ...201020338785
survey for antibodies to infectious bursal disease virus serotype 2 in wild turkeys and sandhill cranes of florida, usa.captive-reared whooping cranes (grus americana) released into florida for the resident reintroduction project experienced unusually high mortality and morbidity during the 1997-98 and 2001-02 release seasons. exposure to infectious bursal disease virus (ibdv) serotype 2 as evidenced by seroconversion was suspected to be the factor that precipitated these mortality events. very little is known about the incidence of ibd in wild bird populations. before this study, natural exposure had not been do ...201020688680
field efficacy trial of a novel hvt-ibd vector vaccine for 1-day-old broilers.two vaccination programmes for infectious bursal disease (ibd) were compared in broiler chickens with maternal immunity, placed on two farms. a turkey herpes virus (hvt)-ibd vector vaccine was administered by the subcutaneous route, at the hatchery, into the chicks of farm a at the age of 1 day. on farm b, an attenuated intermediate live ibd vaccine was given orally at the ages of 17 and 24 days. the vaccine uptake was monitored via serology and bursa/body weight ratio evolution, as well as pcr- ...200919041678
development of differential rt-pcr assays and molecular characterization of the complete vp1 gene of five strains of very virulent infectious bursal disease virus.several antigenic and pathogenic subtypes of infectious bursal disease virus (ibdv) have been identified worldwide. simple and quick differential diagnostic assays are vital for implementing control and prevention strategies for infectious bursal disease (ibd). currently reverse transcriptase-polymerase chain reaction/restriction fragment length polymorphism analysis (rt-pcr/rflp) and real-time rt-pcr detection have been used. however, the rt-pcr/rflp analysis is time consuming and not feasible ...200718251405
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
compatibility of turkey herpesvirus-infectious bursal disease vector vaccine with marek's disease rispens vaccine injected into day-old pullets.mixtures of turkey herpesvirus (hvt) and rispens poultry vaccines have been used worldwide for over 20 yr, mainly for vaccination of future layers and breeders. with increasing virulence of marek's disease (md) virus strains, vaccination strategies are evolving toward the use of vaccines combining hvt and rispens. a single vaccination either in ovo or at 1 day of age with the hvt + infectious bursal disease (ibd) vector vaccine is efficient against ibd. however, with vaccination programs that in ...201121500646
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