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formation of stable homodimer via the c-terminal alpha-helical domain of coronavirus nonstructural protein 9 is critical for its function in viral replication.coronaviruses devote more than three quarters of their coding capacity to encode two large polyproteins (1a and 1ab polyproteins), which are proteolytically processed into 15-16 mature, nonstructural replicase proteins (nsp1 to 16). these cleavage products are believed to play essential roles in replication of the giant rna genome of approximately 30 kb and transcription of a nested set of 5 to 9 subgenomic rna species by a unique discontinuous transcription mechanism. in this report, one of the ...200919022466
infectious bronchitis virus induces acute interferon-gamma production through polyclonal stimulation of chicken leukocytes.infectious bronchitis virus, a member of the coronaviridae, is a respiratory pathogen in poultry. we found that in vitro stimulation with ibv resulted in chifn-gamma production in splenocytes of both infected birds and uninfected birds. the non-specific stimulation did not occur when other avian viruses or other coronaviruses were used or when mammalian cells were stimulated with ibv. inactivation of ibv reduced chifn-gamma production, but chifn-gamma remained elevated compared to unstimulated c ...200919070879
identification of taiwan and china-like recombinant avian infectious bronchitis viruses in taiwan.infectious bronchitis virus (ibv) infections in poultry cause great economic losses to the poultry industry worldwide. the emergence of viral variants complicates disease control. the ibv strains in taiwan were clustered into two groups, taiwan group i and taiwan group ii, based on the s1 gene. a variant was previously identified and showed a distinct s1 gene homology with other local strains. this study investigated the 3' 7.3 kb genome of eight taiwan strains isolated from 1992 to 2007. the ge ...200919100792
comparative analysis of the sialic acid binding activity and the tropism for the respiratory epithelium of four different strains of avian infectious bronchitis virus.avian infectious bronchitis virus (ibv) is a major pathogen in commercial poultry flocks. we recently demonstrated that sialic acid serves as a receptor determinant for ibv on the tracheal epithelium. here we compared the ibv strains beaudette, 4/91, italy02, and qx for their sialic acid-binding properties. we demonstrate that sialic acid binding is important for the infection of primary chicken kidney cells and the tracheal epithelium by all four strains. there were only slight differences betw ...200919156578
induction of eggshell apex abnormalities by mycoplasma synoviae: field and experimental studies.a novel eggshell pathology, characterized by an altered shell surface, thinning, increased translucency, and cracks and breaks in the eggshell apex, has become increasingly common in layer flocks of various breeds in the netherlands. two field studies found an association between the eggshell apex abnormalities (eaa) and infection with mycoplasma synoviae. m. synoviae was isolated from the oviduct of birds that produced abnormal eggs, but not from birds in control flocks, although both affected ...200919156584
backyard chicken flocks pose a disease risk for neotropic birds in costa rica.pathogens of free-ranging chickens create a risk of disease for wild birds, some of which migrate to the united states, as well as potential economic losses for resource-poor farmers. free-roaming backyard chickens are commonly kept in shade-grown coffee plantations, habitats that attract large numbers of wild birds. the husbandry and pathogen prevalence of backyard chicken flocks in san luis, costa rica, were investigated. based on serologic evidence, newcastle disease virus, infectious laryngo ...200819166045
infectious bronchitis virus in the chicken harderian gland and lachrymal fluid: viral load, infectivity, immune cell responses, and effects of viral immunodeficiency.we compared detection of infectious bronchitis virus (ibv) by quantitative rt-pcr (qrt-pcr) in tears and trachea of ibv-infected chickens and found that quantitative detection of ibv rna in tears is more sensitive than in tracheal homogenates. furthermore, we demonstrated that ibv contained in chicken lachrymal fluid is infectious and that tears of ibv-infected chickens can be used to infect naive chickens. we compared the immune responses to ibv in the harderian gland and cecal tonsils of immun ...200819166051
isolation of 4/91 type of infectious bronchitis virus as a new variant in japan and efficacy of vaccination against 4/91 type field isolate.among field isolates of infectious bronchitis virus (ibv) from recent outbreaks, some isolates that were classified into the 4/91 genotype, by analysis of the s1 gene, have been confirmed to be a new variant in japan. to elucidate the characteristics of these isolates, pathogenicity in chicks and the efficacy of vaccines against this new variant were examined. severe respiratory symptoms were observed in 4-day-old specific pathogen free chicks inoculated with a 4/91 genotype isolate, either jp/w ...200819166052
complete genomic sequence analysis of infectious bronchitis virus ark dpi strain and its evolution by recombination.an infectious bronchitis virus arkansas dpi (ark dpi) virulent strain was sequenced, analyzed and compared with many different ibv strains and coronaviruses. the genome of ark dpi consists of 27,620 nucleotides, excluding poly (a) tail, and comprises ten open reading frames. comparative sequence analysis of ark dpi with other ibv strains shows striking similarity to the conn, gray, jmk, and ark 99, which were circulating during that time period. furthermore, comparison of the ark genome with oth ...200819102764
existence of avian infectious bronchitis virus with a european-prevalent 4/91 genotype in japan.eight isolates of infectious bronchitis virus (ibv) were obtained from various prefectures in japan during 2003-2007 and were genetically analyzed by reverse transcriptase-polymerase chain reaction (rt-pcr) coupled with direct sequencing. these ibv isolates were classified into three genetic groups, including two that have already been reported (jp-i and jp-iii). the remaining group is related to the 4/91 (also known as 793/b) type, prevalent mainly in european countries, and has not been identi ...200819122402
pathogenicity of infectious bronchitis virus isolates from ontario chickens.infectious bronchitis (ib) is one of the important viral diseases of chickens, and in spite of regular vaccination, ib is a continuous problem in canadian poultry operations. in an earlier study using sentinel chickens we determined the incidence of infectious bronchitis virus (ibv) in ontario commercial layer flocks. the objective of this study was to determine the pathogenicity of 5 nonvaccine-related ibv isolates recovered from the sentinel birds. the clinical signs, gross, and histological l ...200819086372
the preparation of chicken tracheal organ cultures for virus isolation, propagation, and titration.chicken tracheal organ cultures (tocs), comprising transverse sections of chick embryo trachea with beating cilia, have proved useful in the isolation of several respiratory viruses and as a viral assay system, using ciliostasis as the criterion for infection. a simple technique for the preparation of chicken tracheal organ cultures in glass test tubes, in which virus growth and ciliostasis can be readily observed, is described.200819057860
rt-pcr detection of avian coronaviruses of galliform birds (chicken, turkey, pheasant) and in a parrot.of the many primer combinations that we have investigated for the detection of avian coronaviruses, two have worked better than any of the others: they worked with the largest number of strains/samples of a given coronavirus and the most species of avian coronavirus, and they also produced the most sensitive detection tests. the primer combinations were: oligonucleotide pair 2bp/4bm, which is in a region of gene 1 that is moderately conserved among all species of coronavirus (1); and utr11-/utr4 ...200819057865
transient dominant selection for the modification and generation of recombinant infectious bronchitis coronaviruses.we have developed a reverse genetics system for the avian coronavirus infectious bronchitis virus (ibv) in which a full-length cdna corresponding to the ibv genome is inserted into the vaccinia virus genome under the control of a t7 promoter sequence. vaccinia virus as a vector for the full-length ibv cdna has the advantage that modifications can be introduced into the ibv cdna using homologous recombination, a method frequently used to insert and delete sequences from the vaccinia virus genome. ...200819057872
generation of recombinant coronaviruses using vaccinia virus as the cloning vector and stable cell lines containing coronaviral replicon rnas.coronavirus reverse genetic systems have become valuable tools for studying the molecular biology of coronavirus infections. they have been applied to the generation of recombinant coronaviruses, selectable replicon rnas, and coronavirus-based vectors for heterologous gene expression. here we provide a collection of protocols for the generation, cloning, and modification of full-length coronavirus cdna using vaccinia virus as a cloning vector. based on cloned coronaviral cdna, we describe the ge ...200819057873
generating antibodies to the gene 3 proteins of infectious bronchitis virus.infectious bronchitis virus (ibv), a group 3 coronavirus, produces three proteins (ibv e, ibv 3a, and ibv 3b) from subgenomic mrna 3 during infection. ibv e, a viral envelope protein, plays a role in virus budding, possibly by altering membrane morphology at the virus assembly site. in addition to this role, ibv e may also function as a viroporin, although no data from infected cells have confirmed this possibility definitively. conversely, the ibv 3a and ibv 3b proteins are nonstructural protei ...200819057877
isolation and propagation of coronaviruses in embryonated eggs.the embryonated egg is a complex structure comprising an embryo and its supporting membranes (chorioallantoic, amniotic, yolk). the developing embryo and its membranes provide the diversity of cell types that are needed for successful replication of a wide variety of different viruses. within the family coronaviridae, the embryonated egg has been used as a host system primarily for two group 3 coronaviruses, infectious bronchitis virus (ibv) and turkey coronavirus (tcov), but it also has been sh ...200819057881
qx genotypes of infectious bronchitis virus circulating in europe. 200819011250
pathogenicity of a qx strain of infectious bronchitis virus in specific pathogen free and commercial broiler chickens, and evaluation of protection induced by a vaccination programme based on the ma5 and 4/91 serotypes.the aims of this study were firstly to evaluate the pathogenicity of an italian isolate of the qx strain of infectious bronchitis (ib) virus using 1-day-old female specific pathogen free chicks (layer type) and 1-day-old female commercial broiler type chickens, and secondly to assess the level of protection induced in these birds by a vaccination programme including the ib massachusetts and 4/91 serotype live attenuated vaccines. unvaccinated birds showed clinical signs of varying severity, pred ...200818798022
the immunoreactivity of a chimeric multi-epitope dna vaccine against ibv in chickens.epitope-based vaccines designed to induce cellular immune response and antibody responses specific for infectious bronchitis virus (ibv) are being developed as a means for increasing vaccine potency. in this study, we selected seven epitopes from the spike (s1), spike (s2), and nucleocapsid (n) protein and constructed a multi-epitope dna vaccine. the 7-day-old chickens were immunized intramuscularly with multi-epitope dna vaccine encapsulated by liposome and boosted two weeks later, and were cha ...200818840402
transmissibility of infectious bronchitis virus h120 vaccine strain among broilers under experimental conditions.the aim of this study was to quantify transmission of infectious bronchitis virus (ibv) h120 vaccine strain among broilers, and to assess whether birds that have been exposed to vaccine strain-shedding birds were protected against clinical signs after infection with a virulent strain of the same serotype. a transmission experiment and a replicate were carried out, each with six groups of commercial broilers. at day of hatch (n = 30) or at 15 days of age (n = 20), half of each group was inoculate ...200818939636
baculovirus up-regulates antiviral systems and induces protection against infectious bronchitis virus challenge in neonatal chicken.in this study, the antheraea pernyi nuclear polyhedrosis virus (apnpv), a member of the baculovirus family, is evaluated for its stimulation of chicken peripheral blood mononuclear cells (pbmc) and macrophage cell line hd 11 in vitro, and protection against infectious bronchitis virus (ibv) in neonatal chickens in vivo. this study showed that apnpv significantly enhanced inflammatory cytokine mrna expression in chicken pbmc and hd 11 cells through the clathrin-dependent endocytic and endosomal m ...200818707025
sequence analysis of the gene coding for the s1 glycoprotein of infectious bronchitis virus (ibv) strains from new zealand.four new infectious bronchitis virus (ibv) strains (t6, k32, k43, and k87) were isolated from clinically infected chickens in new zealand. these strains were compared with four strains (a, b, c, and d), which had circulated 25 years previously, by sequencing the gene coding for the s1 subunit of the spike glycoprotein. analysis of the nucleotide and deduced amino acid sequences revealed that the eight strains from new zealand are genetically related and share greater than 82.8% nucleotide and 79 ...200818712588
viral nucleolar localisation signals determine dynamic trafficking within the nucleolus.localisation of both viral and cellular proteins to the nucleolus is determined by a variety of factors including nucleolar localisation signals (nolss), but how these signals operate is not clearly understood. the nucleolar trafficking of wild type viral proteins and chimeric proteins, which contain altered nolss, were compared to investigate the role of nolss in dynamic nucleolar trafficking. three viral proteins from diverse viruses were selected which localised to the nucleolus; the coronavi ...200818775548
a chromatographic strip test for rapid detection of one lineage of the h5 subtype of highly pathogenic avian influenza.a rapid immune colloidal gold test strip for detecting 1 lineage of the h5 subtype of highly pathogenic avian influenza was developed based on membrane chromatography with monoclonal antibodies (mabs) against hemagglutinin (ha) of the h5 subtype of avian influenza virus (aiv). bagg albino c mice that were immunized with aiv a/goose/guangdong/3/96(h5n1) yielded 4 hybridomas secreting mabs (1a6, 1b8, 3c4, and 8f6) specific for ha. monoclonal antibody 3c4 was conjugated with colloidal gold as the d ...200818776087
purification, crystallization and preliminary crystallographic analysis of avian infectious bronchitis virus nsp3 adrp domain.avian infectious bronchitis virus (ibv) encodes 15 nonstructural proteins (nsps) which play crucial roles in rna transcription and genome replication. one of them, nsp3, contains an adrp (adenosine diphosphate-ribose-1'-phosphatase) domain which was revealed in recent studies to have adp-ribose-1'-monophosphatase (appr-1'-pase) activity. appr-1'-pase catalyzes the conversion of adp-ribose-1'-monophosphate (appr-1'-p) to adp-ribose in the trna-splicing pathway. the gene segment encoding the ibv n ...200818765908
proteolytic processing of polyproteins 1a and 1ab between non-structural proteins 10 and 11/12 of coronavirus infectious bronchitis virus is dispensable for viral replication in cultured cells.coronavirus 3c-like proteinase (3clpro) plays important roles in viral life cycle through extensive processing of the polyproteins 1a and 1ab into 12 mature, non-structural proteins (nsp5-nsp16). structural and biochemical studies have revealed that all confirmed 3clpro cleavage sites have a conserved gln residue at the p1 position, which is thought to be absolutely required for efficient cleavage. recent studies on murine hepatitis virus (mhv) showed that processing of the 1a polyprotein at the ...200818678384
identification of a newly isolated avian infectious bronchitis coronavirus variant in china exhibiting affinity for the respiratory tract.twelve infectious bronchitis virus (ibv) isolates obtained from commercial chickens in china between 2005 and 2006 were characterized by reverse transcriptase-polymerase chain reaction (rt-pcr) and the sequencing of the entire s1 gene. ck/ch/lsd/05i--an ibv variant, which was unlike the nephropathogenic ibv isolates found in china--exhibited an affinity for the respiratory tract. the variant was identified by phylogenic analysis and basic local alignment search tool (blast) searches of the entir ...200818646462
genetic diversity of avian infectious bronchitis virus isolates in korea between 2003 and 2006.thirty-three field isolates of avian infectious bronchitis virus (ibv) were recovered from commercial chicken flocks in korea between 2003 and 2006 and were characterized phylogenetically by nucleotide sequence analysis of the ibv s1 gene hyper-variable region. our phylogenetic analysis revealed that recent field isolates of ibv formed at least three distinct phylogenetic types, including k-i, k-ii, and k-iii. k-i type ibv consisted of indigenous, 13 ibv isolates which evolved from the kr-ej/95 ...200818646466
field evaluation of maternal antibody transfer to a group of pathogens in meat-type chickens.this study was conducted to evaluate the rate of antibody transfer on a flock basis from hens to their day-old chicks in meat-type chickens raised in a commercial setting. fifteen randomly selected hens from a commercial broiler-breeder flock were bled at 37, 40, and 45 wk of age. at day of bleeding, the collected eggs were identified and tracked through hatching where 30 hatchlings were randomly sampled and bled from the jugular vein. antibodies against 10 different pathogens were quantified fr ...200818648048
role of phosphorylation clusters in the biology of the coronavirus infectious bronchitis virus nucleocapsid protein.the coronavirus infectious bronchitis virus (ibv) nucleocapsid (n) protein is an rna binding protein which is phosphorylated at two conserved clusters. kinetic analysis of rna binding indicated that the c-terminal phosphorylation cluster was involved in the recognition of viral rna from non-viral rna. the ibv n protein has been found to be essential for the successful recovery of ibv using reverse genetics systems. rescue experiments indicated that phosphorylated n protein recovered infectious i ...200817931676
molecular survey of avian respiratory pathogens in commercial broiler chicken flocks with respiratory diseases in jordan.acute respiratory tract infections are of paramount importance in the poultry industry. avian influenza virus (aiv), infectious bronchitis virus (ibv), newcastle disease virus (ndv), avian pneumovirus (apv), and mycoplasma gallisepticum (mg) have been recognized as the most important pathogens in poultry. in this study, trachea swabs from 115 commercial broiler chicken flocks that suffered from respiratory disease were tested for aiv subtype h9n2, ibv, ndv, and apv by using reverse transcription ...200818281569
identification of the avian infectious bronchitis coronaviruses with mutations in gene 3.the sequence of a 6.0-kb fragment was compared in the 3'-encoding region of the genome in 27 infectious bronchitis virus (ibv) strains. all these strains have the same s-3-m-5-n gene order, as is the case for other ibvs. however, the sizes of the corresponding open reading frames (orfs) of some genes varied among the virus strains. phylogenetic analysis and sequence alignments demonstrated that recombination events had occurred in the origin and evolution of the strains ck/ch/lsd/03i and ck/ch/l ...200818295413
enhancement of the immunogenicity of an infectious bronchitis virus dna vaccine by a bicistronic plasmid encoding nucleocapsid protein and interleukin-2.a dna vaccine against infectious bronchitis virus (ibv) can induce specific humoral and cell-mediated immunity. however, compared to conventional vaccines, dna vaccines usually induce poor antibody responses. to develop a more potent ibv dna vaccine formulations, a monocistronic vector encoding the nucleocapsid protein of ibv and a bicistronic vector separately encoding the nucleocapsid protein and immune-stimulatory interleukin-2 were constructed. when the dna vaccines were administered to the ...200818329109
molecular subtype of infectious bronchitis virus in broiler flocks in jordan.infectious bronchitis virus (ibv) causes respiratory disease in chickens all over the world. infectious bronchitis virus has many serotypes that do not confer cross protection against each other. the current study was designed to know which ibv types were circulating in jordanian broiler chickens. tracheal swabs from 175 broiler flocks at the acute phase of respiratory disease were collected. the swabs were subjected to rna extraction and tested by reverse transcription pcr (rt-pcr). specific-ne ...200818339986
the role of phagocytic cells in enhanced susceptibility of broilers to colibacillosis after infectious bronchitis virus infection.colibacillosis results from infection with avian pathogenic escherichia coli bacteria. healthy broilers are resistant to inhaled e. coli, but previous infection with vaccine or virulent strains of infectious bronchitis virus (ibv) predisposes birds for severe colibacillosis. we investigated whether ibv affects recruitment and function of phagocytic cells and examined no production, phagocytic and bactericidal activity, and kinetics of peripheral blood mononuclear cells (pbmc) and splenocytes. mo ...200818359518
predicting ribosomal frameshifting efficiency.many retroviruses use -1 ribosomal frameshifting as part of the mechanism in translational control of viral protein synthesis. quantitative prediction of the efficiency of -1 frameshifting is crucial for understanding the viral gene expression. here we investigate the free energy landscape for a minimal -1 programmed ribosomal frameshifting machinery, including the codon-anticodon base pairs at the slippery site, the downstream messenger rna structure and the spacer between the slippery site and ...200818367782
infection of the tracheal epithelium by infectious bronchitis virus is sialic acid dependent.avian infectious bronchitis virus (ibv) is a coronavirus that infects chickens via the respiratory epithelium as primary target cells. the binding of coronaviruses to the cell surface is mediated by the viral surface protein s. recently we demonstrated that alpha2,3-linked sialic acid serves as a receptor determinant for ibv on vero cells and primary chicken embryo kidney cells. here we analyze the importance of the sialic acid binding activity for the infection of tracheal organ cultures (tocs) ...200818396435
isolation and characterization of chlamydophila psittaci isolated from laying hens with cystic oviducts.the objective of this study was to isolate and identify a hypothetical chlamydiaceae pathogen from laying hens with an oviduct cyst, and to characterize its potential causal relation with decreased egg production. our clinical survey showed that cystic oviducts were prevalent at rates of 10% and 15.1% in breeder and commercial hen flocks, respectively. chlamydial antigens were detected in 20 of 50 pharyngeal swabs (40%) and in 17 of 20 oviduct tissues (85%) using enzyme-linked immunosorbent assa ...200818459300
health evaluation of free-ranging humboldt penguins (spheniscus humboldti) in peru.as part of ongoing ecological studies of humboldt penguins (spheniscus humboldti) at punta san juan, ica department, peru, health surveys were conducted in november 1992, 1993, and 1994. in the three surveys, 98 birds in total were handled for examination, and blood was collected for laboratory analysis from 90 of these birds. all birds seemed to be in good condition. body weights of females were significantly lower in 1994 than in the other years. fleas (parapsyllus humboldti) and ticks (ornith ...200818459309
complete genomic sequence of turkey coronavirus.turkey coronavirus (tcov), one of the least characterized of all known coronaviruses, was isolated from an outbreak of acute enteritis in young turkeys in ontario, canada, and the full-length genomic sequence was determined. the full-length genome was 27,632 nucleotides plus the 3' poly(a) tail. two open reading frames, orfs 1a and 1b, resided in the first two thirds of the genome, and nine additional downstream orfs were identified. a gene for hemagglutinin-esterase was absent in tcov. the regi ...200818468711
avian coronavirus infectious bronchitis attenuated live vaccines undergo selection of subpopulations and mutations following vaccination.in this study, we were interested in determining if high titered egg adapted modified live infectious bronchitis virus (ibv) vaccines contain spike gene related quasispecies that undergo selection in chickens, following vaccination. we sequenced the spike glycoprotein of 12 ibv vaccines (5 different serotypes from 3 different manufacturers) directly from the vaccine vial, then compared that sequence with reisolated viruses from vaccinated and contact-exposed birds over time. we found differences ...200818262691
targeted protein accumulation promoted by autoassembly and its recovery from plant cells.the expression of a fusion protein formed between the avian infectious bronchitis virus m protein and the bacterial enzyme beta-glucuronidase (gus) in plants promotes the formation of new organization of the endoplasmic reticulum in tobacco plants. this unusual organization of the membranes, never present in nontransformed plants, has been explained by the oligomerization of the gus domains of the ibvm-gus fusion proteins. these specific organized membranes could have broad implications for biot ...200818264977
complete nucleotide sequence of polyprotein gene 1 and genome organization of turkey coronavirus.the complete nucleotide sequence of polyprotein gene 1 and the assembled full-length genome sequence are presented for turkey coronavirus (tcov) isolates 540 and atcc. the tcov polyprotein gene encoded two open reading frames (orfs), which are translated into two products, pp1a and pp1ab, the latter being produced via -1 frameshift translation. tcov polyprotein pp1a and pp1ab were predicted to be processed to 15 non-structure proteins (nsp2-nsp16), with nsp1 missing. clustalw analysis revealed 8 ...200818514348
[genetic variation of s1 gene hypervariable region i of infectious bronchitis viruses isolated in different periods in guangxi].the s1 gene hypervariable region i (hvr i) of 22 infectious bronchitis virus (ibv) strains isolated in guangxi during the period of 1985-2007 were sequenced and compared to that of the other ibv reference strains and the pigeon coronavirus isolates. a phylogenetic tree based on nucleotide sequences of hvr i of all the ibv showed that they were classified into 5 distinct clusters. 16 out of 22 ibv isolates were grouped into cluster i, and had higher homology with pigeon coronavirus isolates but l ...200818533344
[evaluation of the protection conferred by several avian infectious bronchitis attenuated vaccines against the field strain ck/ch/ldl/97 i in china].the entire s1 protein gene of five infectious bronchitis (ib) vaccine strains (jaas, ibn, jilin, j9, h120) used in china were compared with that of the ib field isolate ck/ch/ldl/97 i present in china. the nucleotide and deduced amino acid similarities between the five ib vaccine strains and the field strain, ck/ch/ldl/97 i, were not more than 76.4% and 78.7%, respectively. phylogenetic analysis based on the s1 gene showed that the vaccine strains and the field strain belonged to different clust ...200818536105
protection abilities of influenza b virus dna vaccines expressing hemagglutinin, neuraminidase, or both in mice.every year, a vaccination against influenza b virus (ibv) is essential due to an antigenic variation. development of an efficient and convenient vaccine is important for the prevention of viral infection. this study reports examination of the protective immunity in mice evoked by a single inoculation of plasmid dna expressing hemagglutinin (ha dna) or neuraminidase (na dna) of ibv. the ha dna or na dna was injected intramuscularly into balb/c mice separately or as a mixture. the injection of pla ...200818564897
a reverse transcriptase-polymerase chain reaction survey of infectious bronchitis virus genotypes in western europe from 2002 to 2006.a survey of infectious bronchitis virus (ibv) genotypes in poultry flocks in selected countries in western europe was carried out between march 2002 and december 2006. identification of ibv was by reverse transcriptase-polymerase chain reaction of rna extracted from oropharyngeal swabs taken from poultry flocks exhibiting signs of clinical disease thought to be attributable to ibv. part of the hypervariable s1 gene of ibv was sequenced to differentiate between the various genotypes. during the s ...200818568650
rapid selection in chickens of subpopulations within arkdpi-derived infectious bronchitis virus vaccines.we examined spike (s) gene sequences of the virus populations of four different commercial arkdpi-derived infectious bronchitis coronavirus vaccines before and during a single passage in specific pathogen free chickens. we found different degrees of genetic heterogeneity among the four vaccines before passage in chickens, ranging from no apparent heterogeneity to heterogeneity in 20 positions in the s gene. in all except one position, nucleotide differences were non-synonymous. the majority of a ...200818568656
molecular mechanisms of primary and secondary mucosal immunity using avian infectious bronchitis virus as a model system.although mucosal immune responses are critical for protection of hosts from clinical illness and even mortality caused by mucosal pathogens, the molecular mechanism of mucosal immunity, which is independent of systemic immunity, remains elusive. to explore the mechanistic basis of mucosal protective immunity, gene transcriptional profiling in mucosal tissues was evaluated after the primary and secondary immunization of animals with an attenuated avian infectious bronchitis virus (ibv), a prototy ...200817983666
characterization of the mechanical unfolding of rna pseudoknots.the pseudoknot is an important rna structural element that provides an excellent model system for studying the contributions of tertiary interactions to rna stability and to folding kinetics. rna pseudoknots are also of interest because of their key role in the control of ribosomal frameshifting by viral rnas. their mechanical properties are directly relevant to their unfolding by ribosomes during translation. we have used optical tweezers to study the kinetics and thermodynamics of mechanical u ...200818021801
biological response of chickens (gallus gallus domesticus) induced by corticosterone and a bacterial endotoxin.experiments were conducted with chickens exposed to corticosterone and lipopolysaccharide (lps) from escherichia coli, with the aim of evaluating and differentiating their effects on endocrine, metabolic and immune response. both, corticosterone and lps significantly elevated plasma corticosterone concentrations and increased heterophil to lymphocyte (h/l) ratios 1 h, 3 h and 24 h post-treatments. repeated exposure to corticosterone caused a prolonged elevation of plasma corticosterone concentra ...200818024213
infectious bronchitis viruses with a novel genomic organization.a number of novel infectious bronchitis viruses (ibvs) were previously identified in commercial poultry in australia, where they caused significant economic losses. since there has been only limited characterization of these viruses, we investigated the genomic and phenotypic differences between these novel ibvs and other, classical ibvs. the 3' 7.5 kb of the genomes of 17 australian ibv strains were sequenced, and growth properties of 6 of the strains were compared. comparison of sequences of t ...200818045937
construction and functional test of a chicken mhc-i (bf2*15)/peptide tetramer.the major histocompatibility complex class i (mhc class i) peptide tetramer is a sensitive and valuable tool to evaluate antigen-specific cytotoxic t lymphocytes (ctls) of many animal species. to date, no chicken mhc class i peptide tetramer has been reported. in this report, we describe construction and functional evaluation of a chicken mhc-i (bf2*15)/peptide tetramer. to construct the chicken mhc class i peptide tetramer, genes of the chicken mhc-i alpha chain (bf2*15) and beta2 microglobulin ...200818077001
structures of two coronavirus main proteases: implications for substrate binding and antiviral drug design.coronaviruses (covs) can infect humans and multiple species of animals, causing a wide spectrum of diseases. the coronavirus main protease (m(pro)), which plays a pivotal role in viral gene expression and replication through the proteolytic processing of replicase polyproteins, is an attractive target for anti-cov drug design. in this study, the crystal structures of infectious bronchitis virus (ibv) m(pro) and a severe acute respiratory syndrome cov (sars-cov) m(pro) mutant (h41a), in complex w ...200818094151
the spike protein of infectious bronchitis virus is retained intracellularly by a tyrosine motif.we have analyzed the intracellular transport of the spike (s) protein of infectious bronchitis virus (ibv), an avian coronavirus. surface expression was analyzed by immunofluorescence microscopy, by surface biotinylation, and by syncytium formation by s-expressing cells. by applying these methods, the s protein was found to be retained intracellularly. tyr1143 in the cytoplasmic tail was shown to be a crucial component of the retention signal. deletion of a dilysine motif that has previously bee ...200818094153
genotyping of canadian isolates of fowl adenoviruses.five hundred and seventy-three clinical submissions with fowl adenovirus (fadv) involvement were examined to investigate the association of different types of fadv with clinical problems related to fadv infection. samples were received from 2000 to 2006 and originated from seven canadian provinces. four hundred and eighty-seven submissions were inclusion body hepatitis (ibh) related, while 86 were not ibh related. viruses isolated from 287 samples were further analysed by hexon gene loop 1 seque ...200818202956
chinese qx strain of infectious bronchitis virus isolated in the uk. 200818204039
molecular epidemiology and evolution of avian infectious bronchitis virus in spain over a fourteen-year period.an in-depth molecular study of infectious bronchitis viruses (ibv) with particular interest in evolutionary aspects of ibv in spain was carried out in the present study based on the s1 gene molecular characterization of twenty-six spanish strains isolated over a fourteen-year period. four genotypes were identified based on s1 gene sequence analyses and phylogenetic studies. a drastic virus population shift was demonstrated along time and the novel italy 02 serotype was shown to have displaced th ...200818215734
coronavirus spike protein inhibits host cell translation by interaction with eif3f.in response to viral infection, the expression of numerous host genes, including predominantly a number of proinflammatory cytokines and chemokines, is usually up-regulated at both transcriptional and translational levels. it was noted that in cells infected with coronavirus, transcription and translation of some of these genes were differentially induced. drastic induction of their expression at the transcriptional level was observed in cells infected with coronavirus. however, induction of the ...200818231581
coinfection of avian influenza virus (h9n2 subtype) with infectious bronchitis live vaccine.avian influenza virus of h9n2 subtype is pathotyped as a non-highly pathogenic virus. however, frequent incidences of avian influenza of high mortality that are caused by h9n2 viruses have been observed in broiler chicken farms in iran and some other asian countries. coinfections or environmental factors may be involved in such cases. infectious microorganisms have been implicating in taking part in the cases of coinfection. we studied the effect of experimental coinfection of h9n2 avian influen ...200818247102
comparison of sybr green i, elisa and conventional agarose gel-based pcr in the detection of infectious bursal disease virus.the current available molecular method to detect infectious bursal disease virus (ibdv) is by reverse transcriptase-polymerase chain reaction (rt-pcr). however, the conventional pcr is time consuming, prone to error and less sensitive. in this study, the performances of sybr green i real-time pcr, enzyme-linked immunosorbent assay (elisa) and conventional agarose detection methods in detecting specific ibdv pcr products were compared. we found the real-time pcr was at least 10 times more sensiti ...200816971101
an arginine-to-proline mutation in a domain with undefined functions within the helicase protein (nsp13) is lethal to the coronavirus infectious bronchitis virus in cultured cells.genetic manipulation of the rna genomes by reverse genetics is a powerful tool to study the molecular biology and pathogenesis of rna viruses. during construction of an infectious clone from a vero cell-adapted coronavirus infectious bronchitis virus (ibv), we found that a g-c point mutation at nucleotide position 15526, causing arg-to-pro mutation at amino acid position 132 of the helicase protein, is lethal to the infectivity of ibv on vero cells. when the in vitro-synthesized full-length tran ...200716979681
phylogenetic analysis of partial s1 and n gene sequences of infectious bronchitis virus isolates from italy revealed genetic diversity and recombination.a total of ten infectious bronchitis virus (ibv) isolates collected from commercial chickens in italy in 1999 were characterized by rt-pcr and sequencing of the s1 and n genes. phylogenetic analysis based on partial s1 gene sequences showed that five field viruses clustered together with 793/b-type strains, having 91.3-98.5% nucleotide identity within the group, and one isolate had very close sequence relationship (94.6% identity) with 624/i strain. these two ibv types have been identified in it ...200717043759
capillary zone electrophoresis method for fingerprint of allantoic fluid in normal and infected spf embryonated chicken eggs.a capillary zone electrophoresis method was developed for fingerprint determination of allantoic fluid in specific pathogen free (spf) embryonated chicken eggs. the effects of some crucial parameters, such as buffer type, ph, wavelength and running voltage on the separation were studied systematically. the components of the allantoic fluid were well separated using a fused-silica uncoated capillary with an effective length of 50 cm and an internal diameter of 50 microm. one hundred millimolars s ...200717055591
infectious bronchitis virus serotypes in poultry flocks in jordan.infectious bronchitis virus (ibv) causes respiratory disease in chickens all over the world. ibv has many serotypes that do not confer cross protection against each other. hemagglutination inhibition (hi) test has been used to determine the serotypes of ibv as a substitute to the more laborious virus neutralization test and the more sophisticated restriction endonuclease digestion or sequencing of the s1 gene. in jordan, no previous studies have been carried out to determine the involvement of i ...200717161477
comparative histopathology of two serotypes of infectious bronchitis virus (t and n1/88) in laying hens and cockerels.the comparative and sequential histopathology of different tissues of unvaccinated laying hens and cockerels were studied in chickens exposed to t and n1/88 strain of infectious bronchitis virus (ibv). the harderian gland and trachea of hens and cockerels in both t- and n1/88-infected groups were damaged to a similar extent. the cecum was unaffected for both strains of ibv in both hens and cockerels. the sequential histopathological changes in hens revealed that ibv multiplies initially in the h ...200717179415
histopathology of two serotypes of infectious bronchitis virus in laying hens vaccinated in the rearing phase.the comparative histopathology of 2 different strains of infectious bronchitis virus (t and n1/ 88) in vaccinated hens was studied at 110 wk of age. the harderian gland showed similar histopathology in t- and n1/88-infected hens. the trachea and kidney of challenged vaccinated hens were protected to a moderate extent, but the oviduct was protected to only a small extent. the severity and persistence of lesions were greater in tubular shell gland, shell gland pouch, and kidney of the t-infected h ...200717179416
preliminary crystallographic analysis of avian infectious bronchitis virus main protease.infectious bronchitis virus (ibv) is the prototype of the genus coronavirus. it causes a highly contagious disease which affects the respiratory, reproductive, neurological and renal systems of chickens, resulting great economic losses in the poultry industry worldwide. the coronavirus (cov) main protease (m(pro)), which plays a pivotal role in viral gene expression and replication through a highly complex cascade involving the proteolytic processing of replicase polyproteins, is an attractive t ...200717183167
characterization of the nuclear export signal in the coronavirus infectious bronchitis virus nucleocapsid protein.the nucleocapsid (n) protein of infectious bronchitis virus (ibv) localizes to the cytoplasm and nucleolus and contains an eight-amino-acid nucleolar retention motif. in this study, a leucine-rich nuclear export signal (nes) (291-lqldglhl-298) present in the c-terminal region of the ibv n protein was analyzed by using alanine substitution and deletion mutagenesis to investigate the relative contributions that leucine residues make to nuclear export and where these residues are located on the str ...200717202223
ribonucleocapsid formation of severe acute respiratory syndrome coronavirus through molecular action of the n-terminal domain of n protein.conserved among all coronaviruses are four structural proteins: the matrix (m), small envelope (e), and spike (s) proteins that are embedded in the viral membrane and the nucleocapsid phosphoprotein (n), which exists in a ribonucleoprotein complex in the lumen. the n-terminal domain of coronaviral n proteins (n-ntd) provides a scaffold for rna binding, while the c-terminal domain (n-ctd) mainly acts as oligomerization modules during assembly. the c terminus of the n protein anchors it to the vir ...200717229691
ultrastructural study of infectious bronchitis virus infection in infundibulum and magnum of commercial laying hens.the infundibulum and magnum of the oviduct were examined in hens in full lay which were infected with two australian strains of infectious bronchitis virus (ibv). the ultramicroscopic changes in the infundibulum and magnum were compared with control hens which had eggs at different positions in the oviduct. the ciliated and granular cells of the surface epithelia and secretory epithelial cells of the tubular glands were the target cells of ibv. no pathological changes were recorded during 2-8 da ...200717321700
feline aminopeptidase n is not a functional receptor for avian infectious bronchitis virus.coronaviruses are an important cause of infectious diseases in humans, including severe acute respiratory syndrome (sars), and have the continued potential for emergence from animal species. a major factor in the host range of a coronavirus is its receptor utilization on host cells. in many cases, coronavirus-receptor interactions are well understood. however, a notable exception is the receptor utilization by group 3 coronaviruses, including avian infectious bronchitis virus (ibv). feline amino ...200717324273
strong antiviral activity of heated and hydrated dolomite--preliminary investigation.heated and hydrated naturally occurring dolomite showed very strong antiviral activity. infectivity of avian and human influenza, avian infectious bronchitis (coronavirus), newcastle disease (paramyxovirus) and avian laryngotracheitis (herpesvirus) viruses dropped at least 1,000 fold following contact with the dolomite for five minutes at 4 degrees c. dolomite is expected to be useful to inhibit the incidence of emerging and re-emerging infectious diseases.200717339770
production and characterization of monoclonal antibodies to (poly100)s1 protein of avian infectious bronchitis virus.fragments within s1 genes ((poly100)s1) of infectious bronchitis virus (ibv) strains zj971, m41 and sc021202 (sc) were subcloned into a prokaryotic expression vector and expressed in escherichia coli. monoclonal antibodies (mabs) against the recombinant (poly100)s1 proteins were produced, characterized and used to analyse epitopes on the s1 subunit of ibv. nine mabs raising from the three (poly100)s1 proteins recognized five different epitopes of the s1 subunit, designated as s1-a, b, c, d and e ...200717348910
characterisation of cyclin d1 down-regulation in coronavirus infected cells.the positive strand rna coronavirus, infectious bronchitis virus (ibv), induces a g2/m phase arrest and reduction in the g1 and g1/s phase transition regulator cyclin d1. quantitative real-time rt-pcr and western blot analysis demonstrated that cyclin d1 was reduced post-transcriptionally within infected cells independently of the cell-cycle stage at the time of infection. confocal microscopy revealed that cyclin d1 decreased in ibv-infected cells as infection progressed and inhibition studies i ...200717359980
sequence changes of infectious bronchitis virus isolates in the 3' 7.3 kb of the genome after attenuating passage in embryonated eggs.attenuated infectious bronchitis virus (ibv) vaccines are available but the relationship between sequence and virulence is not clear. in this study, the sequences of the 3' 7.3 kb of the genome, amplified using reverse transcription-polymerase chain reaction before and after attenuation, were compared to study the relationship between virulence and the sequences of three ibv strains. after attenuation, two to six amino acid substitutions were found in the spike 1 subunit, and two or three amino ...200717364511
structure of the sars coronavirus nucleocapsid protein rna-binding dimerization domain suggests a mechanism for helical packaging of viral rna.coronavirus nucleocapsid proteins are basic proteins that encapsulate viral genomic rna to form part of the virus structure. the nucleocapsid protein of sars-cov is highly antigenic and associated with several host-cell interactions. our previous studies using nuclear magnetic resonance revealed the domain organization of the sars-cov nucleocapsid protein. rna has been shown to bind to the n-terminal domain (ntd), although recently the c-terminal half of the protein has also been implicated in r ...200717379242
correlation between mechanical strength of messenger rna pseudoknots and ribosomal frameshifting.programmed ribosomal frameshifting is often used by viral pathogens including hiv. slippery sequences present in some mrnas cause the ribosome to shift reading frame. the resulting protein is thus encoded by one reading frame upstream from the slippery sequence and by another reading frame downstream from the slippery sequence. although the mechanism is not well understood, frameshifting is known to be stimulated by an mrna structure such as a pseudoknot. here, we show that the efficiency of fra ...200717389398
manipulation of the infectious bronchitis coronavirus genome for vaccine development and analysis of the accessory proteins.infectious bronchitis coronavirus (ibv) is the cause of the single most economically costly infectious disease of domestic fowl in the uk--and probably so in many countries that have a developed poultry industry. a major reason for its continued dominance is its existence as many serotypes, determined by the surface spike protein (s), cross-protection being poor. although controlled to some degree by live and inactivated vaccines, a new generation of ib vaccines is called for. reverse genetic or ...200717416443
different genotypes of nephropathogenic infectious bronchitis viruses co-circulating in chicken population in china.chicken nephropathogenic infectious bronchitis (ib) was prevalent in the most chicken farms during recent years, although the ib vaccination program has been widely performed in china. to characterize the s1 protein of infectious bronchitis virus (ibv) from china, five representative nephropathogenic ib viruses isolated from chickens in different provinces were genetically and phylogenetically analyzed. the results showed that the length of the s1 genes of the isolates were quite different (1,61 ...200717431755
heparan sulfate is a selective attachment factor for the avian coronavirus infectious bronchitis virus beaudette.the avian coronavirus infectious bronchitis virus (ibv) strain beaudette is an embryo-adapted virus that has extended species tropism in cell culture. in order to understand the acquired tropism of the beaudette strain, we compared the s protein sequences of several ibv strains. the beaudette strain was found to contain a putative heparan sulfate (hs)-binding site, indicating that the beaudette virus may use hs as a selective receptor. to ascertain the requirements of cell-surface hs for beaudet ...200717461266
lithium chloride inhibits the coronavirus infectious bronchitis virus in cell culture.the avian coronavirus infectious bronchitis virus (ibv) is a major economic pathogen of domestic poultry that, despite vaccination, causes mortality and significant losses in production. during replication of the rna genome there is a high frequency of mutation and recombination, which has given rise to many strains of ibv and results in the potential for new and emerging strains. currently the live-attenuated vaccine gives poor cross-strain immunity. effective antiviral agents may therefore be ...200717479370
cell cycle arrest and apoptosis induced by the coronavirus infectious bronchitis virus in the absence of p53.manipulation of the cell cycle and induction of apoptosis are two common strategies used by many viruses to regulate their infection cycles. in cells infected with coronaviruses, cell cycle perturbation and apoptosis were observed in several reports. however, little is known about how these effects are brought out, and how manipulation of the functions of host cells would influence the replication cycle of coronavirus. in this study, we demonstrate that infection with coronavirus infectious bron ...200717493653
s1 gene sequence heterogeneity of a pathogenic infectious bronchitis virus strain and its embryo-passaged, attenuated derivatives.infectious bronchitis virus ck/ch/ldl/97i was attenuated by serial passage in chicken embryos. virus of passage 115 was attenuated as determined by clinical response to inoculation to 15-day-old specific pathogen free chickens. the vaccination-challenge test showed that the attenuated passage 115 virus could afford protection against the homologous pathogenic virus, passage 5, by the clinical response. based on the sequence analysis and comparison of the s1 gene, both the pathogenic and attenuat ...200717497337
coronavirus associated with an enteric syndrome on a quail farm.an enteric syndrome was observed in quail (coturnix coturnix) semi-intensively reared for restocking in apulia (southern italy). the birds showed depression, severe diarrhoea, dehydration and reduced growth. mortality occurred particularly in young birds. at necropsy the prominent lesion was enteritis. a coronavirus was detected by electron microscopy and reverse transcriptase-polymerase chain reaction in the faeces and in the intestinal content of the dead quails. the virus could not be cultiva ...200717497340
[construction of recombinant bcg bearing s1 glycoprotein of nephropathogenic ibv and study on its immunogenicity on chickens].glycoprotein si was the major protein to determine infection and immunogenicity of infectious bronchitis virus (ibv). the s1 glycoprotein gene of ibv isolates were amplified by reverse transcriptase-polymerase chain reaction (rt-pcr) and proved to be s1 gene by sequencing. the e. coli-mycobacterium expression shuttle plasmid pr-alpha-s1 was constructed by inserting the s1 gene to the prr3 with human mycobacterium tuberculosis hsp70 promoter and a signal peptide. then the plasmid pr-alpha-s1 was ...200717552243
antiviral activity of carbohydrate-binding agents against nidovirales in cell culture.coronaviruses are important human and animal pathogens, the relevance of which increased due to the emergence of new human coronaviruses like sars-cov, hku1 and nl63. together with toroviruses, arteriviruses, and roniviruses the coronaviruses belong to the order nidovirales. so far antivirals are hardly available to combat infections with viruses of this order. therefore, various antiviral strategies to counter nidoviral infections are under evaluation. lectins, which bind to n-linked oligosacch ...200717560666
detection and seroprevalence of infectious bronchitis virus strains in commercial poultry in pakistan.this study was conducted to investigate the incidence of infectious bronchitis virus (ibv) in commercial broiler and layer flocks in pakistan. serum samples from 16 layers and 9 broiler flocks were screened against m-41, d-274, d-1466, and 4-91 strain antigens using hemagglutination inhibition assay. overall, 88% of the flocks were seropositive for m-41 antibodies, whereas 40, 52, and 8% of the flocks were positive for d-274, d-1466, and 4-91 ibv strains, respectively. the m-41 antigen was also ...200717575179
orchitis in roosters with reduced fertility associated with avian infectious bronchitis virus and avian metapneumovirus infections.the pathogenesis of infection involving both infectious bronchitis virus (ibv) and avian metapneumovirus (ampv) causes reproductive damage in hens after viral replication in the epithelium of the oviduct, resulting in loss of cilia and degeneration and necrosis of the epithelial and glandular cells. although ibv has been indicated as a possible cause of the formation of calcium stones in the epididymus of roosters, a definitive association has not been confirmed. this report describes the detect ...200718251400
evaluating viral interference between infectious bronchitis virus and newcastle disease virus vaccine strains using quantitative reverse transcription-polymerase chain reaction.the potential for infectious bronchitis virus (ibv) and newcastle disease virus (ndv) replication interference was evaluated using quantitative reverse transcription-polymerase chain reaction (qrt-pcr). fourteen-day-old broiler chickens were inoculated via eyedrop with live commercial vaccine strains of ibv and ndv alone or in combination to directly evaluate ibv and ndv replication in the trachea at 1, 3, and 5 days after vaccination. commercial ndv vaccine strains used were b1, vg/ga, and c2. ...200718251404
molecular characterization of infectious bronchitis virus strains isolated from the enteric contents of brazilian laying hens and broilers.infectious bronchitis virus (ibv) is the causative agent of avian infectious bronchitis, which is characterized by respiratory, reproductive, and renal signs. however, the role of ibv as an enteric pathogen in still controversial. in brazil, antigenic groups of ibv divergent from the massachusetts serotype used for vaccination schedules in that country have already been demonstrated. the present study aimed to assess the different genotypes of ibv in brazilian commercial poultry flocks by partia ...200718251411
immunopotentiating effects of four chinese herbal polysaccharides administered at vaccination in chickens.this study was conducted to evaluate the effects of 4 chinese herbal polysaccharides on the production of serum antibodies and the proliferation of peripheral t lymphocytes, including subpopulations in vaccinated chickens. a total of 450 chickens were randomly assigned to 9 groups at 14 d of age and vaccinated first with live newcastle disease (nd)-infectious bronchitis virus vaccine, and second with nd-infectious bronchitis oil adjuvant vaccine at 28 d of age. at the same time as the first vacc ...200718029798
effects of several virucidal agents on inactivation of influenza, newcastle disease, and avian infectious bronchitis viruses in the allantoic fluid of chicken eggs.general theories on the inactivation of viruses in the presence of a concentrated protein, such as the allantoic fluid of chicken eggs, are not useful. that is, although sodium hypochlorite and sodium hydroxide are generally known as strong virucidal agents, they do not sufficiently inactivate viruses in allantoic fluid. we found that benzalkonium chloride (bc) is an effective virucidal agent against influenza, newcastle disease, and avian infectious bronchitis viruses even in the presence of a ...200718032831
pathogenesis of infectious bronchitis virus in vaccinated chickens of two different major histocompatibility b complex genotypes.infectious bronchitis (ib) disease progression in vaccinated chickens after challenge was evaluated in a single commercial line of layer chickens presenting two different major histocompatibility complex (mhc) b complex genotypes. mhc b genotypes were determined by dna sequence-based typing of bf2 alleles. in total, 33 b2/b15 and 47 b2/b21 chickens were vaccinated with an ark-type ib virus (ibv) attenuated vaccine and challenged with ark-type ibv field isolate al/4614/98 14 days later. additiona ...200717992938
sequence analysis of the s1 glycoprotein gene of infectious bronchitis viruses: identification of a novel phylogenetic group in korea.twelve korean infectious bronchitis viruses (ibvs) were isolated in the field from chickens suspected of being carriers of infectious bronchitis between 2001 and 2003. the s1 glycoprotein genes of these ibv isolates were amplified by reverse transcriptase-polymerase chain reaction (rtpcr) and analyzed by restriction fragment length polymorphism (rflp) analysis. these korean ibv isolates were classified into three groups according to their rflp patterns obtained using the restriction enzyme haeii ...200717993755
a recombinant turkey herpesvirus expressing chicken interleukin-2 increases the protection provided by in ovo vaccination with infectious bursal disease and infectious bronchitis virus.in 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
vaccination against the avian infectious bronchitis virus affects sperm concentration, sperm quality and blood testosterone concentrations in cockerels.1. it was previously found that cockerels vaccinated with live attenuated avian infectious bronchitis virus (aibv) have decreased serum testosterone concentrations, epididymal stones and reduced fertility. the objectives of this study were twofold: to determine if reduced fertility following vaccination with live attenuated virus was the result of reduced sperm concentration or reduced sperm quality and to determine if vaccination with a killed strain of virus caused a similar reduction in sperm ...200717952734
isolation and identification of four infectious bronchitis virus strains in china and analyses of their s1 glycoprotein gene.between 2003 and 2005, four strains of infectious bronchitis virus (ibv) were isolated from the vaccinated chicken flocks in china. the results from chicken embryo cross-neutralization assays showed that all the four isolates were relative to strain a2 of ibv, which was isolated in 1996 in beijing and related to strain 4/91. the s1 gene of the spike protein was amplified and sequenced. the nucleotide and amino acid sequence of the s1 gene had a similar degree of identity (88.98-99.28%) among the ...200717289305
coronavirus avian infectious bronchitis virus.infectious bronchitis virus (ibv), the coronavirus of the chicken (gallus gallus), is one of the foremost causes of economic loss within the poultry industry, affecting the performance of both meat-type and egg-laying birds. the virus replicates not only in the epithelium of upper and lower respiratory tract tissues, but also in many tissues along the alimentary tract and elsewhere e.g. kidney, oviduct and testes. it can be detected in both respiratory and faecal material. there is increasing ev ...200717296157
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