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otitis and meningoencephalitis associated with infectious coryza ( avibacterium paragallinarum) in commercial broiler chickens.infectious coryza, caused by avibacterium paragallinarum, is an acute respiratory disease of poultry that can result in substantial morbidity, mortality, and economic losses. in march 2017, the turlock branch of the california animal health and food safety laboratory system encountered an unusual clinical and pathologic presentation of infectious coryza in 6 live, 29-d-old, commercial broiler chickens that were submitted for diagnostic investigation. antemortem evaluation revealed severe neurolo ...201830129392
shell-less egg syndrome (ses) widespread in western canadian layer operations is linked to a massachusetts (mass) type infectious bronchitis virus (ibv) isolate.a disease with a sudden drop in egg production and shell-less eggs called, shell-less egg syndrome (ses) has been observed in western canada egg layer flocks since 2010. the etiology of this disease is not known. we hypothesize that ses is caused by an infectious bronchitis virus (ibv) strain since it is known that ibv replicates in the shell gland causing various eggshell abnormalities. in this study, we screened egg layer flocks, in the provinces of alberta (ab) and saskatchewan (sk), with and ...201830126175
a recombinant newcastle disease virus (ndv) expressing s protein of infectious bronchitis virus (ibv) protects chickens against ibv and ndv.infectious bronchitis virus (ibv) causes a highly contagious respiratory, reproductive and urogenital tract disease in chickens worldwide, resulting in substantial economic losses for the poultry industry. currently, live-attenuated ibv vaccines are used to control the disease. however, safety, attenuation and immunization outcomes of current vaccines are not guaranteed. several studies indicate that attenuated ibv vaccine strains contribute to the emergence of variant viruses in the field due t ...201830097608
safety and efficacy of attenuated classic and variant 2 infectious bronchitis virus candidate vaccines.vaccination programs against infectious bronchitis virus (ibv) in egypt depend on both classical and/or imported variant ibv strain vaccines. however, many ibv outbreaks associated with respiratory distress, nephropathy, and high mortalities were attributed to the circulation of both classical and new nephropathogenic ibv variant 2 strains. in the present study, we report the development of attenuated ibv candidate vaccines using the classic ibv strains (ibm41 and ib2) and a nephropathogenic str ...201830085298
deletion of accessory genes 3a, 3b, 5a or 5b from avian coronavirus infectious bronchitis virus induces an attenuated phenotype both in vitro and in vivo.avian coronavirus infectious bronchitis virus (ibv) infects domestic fowl, resulting in respiratory disease and causing serious losses in unprotected birds. its control is mainly achieved by using live attenuated vaccines. here we explored the possibilities for rationally attenuating ibv to improve our knowledge regarding the function of ibv accessory proteins and for the development of next-generation vaccines with the recently established reverse genetic system for ibv h52 based on targeted rn ...201830067172
protection against virulent infectious bronchitis virus challenge conferred by a recombinant baculovirus co-expressing s1 and n proteins.avian infectious bronchitis virus (ibv) is the causative agent of infectious bronchitis, which results in considerable economic losses. it is imperative to develop safe and efficient candidate vaccines to control ibv infection. in the current study, recombinant baculoviruses co-expressing the s1 and n proteins and mono-expressing s1 or n proteins of the gx-yl5 strain of ibv were constructed and prepared into subunit vaccines rhbm-s1-n, rhbm-s1 and rhbm-n. the levels of immune protection of these ...201829954092
effects of dietary yeast nucleotides supplementation on intestinal barrier function, intestinal microbiota, and humoral immunity in specific pathogen-free chickens.yeast nucleotides are a fine functional additive in human and animals. the effects of dietary yeast nucleotides supplementation on intestinal development, expression of intestinal barrier-related genes, intestinal microbiota, and infectious bronchitis virus (ibv) antibody titer of specific pathogen-free (spf) chickens were investigated. a total of 60 1-d-old chickens were divided into 4 groups, each of which included 3 replicates of 5 chickens. group 1 served as a control that was fed a basal di ...201829945221
viral interference between low pathogenic avian influenza h9n2 and avian infectious bronchitis viruses in vitro and in ovo.low pathogenic avian influenza (lpai) h9n2 and infectious bronchitis virus (ibv) are important pathogens of poultry, causing important economic losses for the sector. replication interference between these two viruses was described using cell cultures (cc) and embryonated chicken eggs (ece). chicken embryo lung (cel) and ece were simultaneously or sequentially infected with ibv vaccine strain (h120) and lpaiv-h9n2 (a/ck/tun/145/2012) to evaluate viral interactionsin vitro and in ovo, respectivel ...201829940196
seroprevalence and genotyping of avian infectious bronchitis virus detected from iranian unvaccinated backyard chickens.different epidemiological studies have found that backyard chickens are a reservoir for poultry diseases. most backyard chicken flocks have a poor level of biosecurity, which increases the risk of spread of diseases. in recent years, the number of backyard chickens has been on the rise in iran. however, the health status of backyard flocks is still poorly documented. thus, this study aimed at examining the seroprevalence of antibodies against infectious bronchitis virus (ibv) and molecular surve ...201829922421
in vitro phagocytosis of opsonized latex beads by hd11 cells as a method to assess the general opsonization potential of chicken serum.opsonins, an important arm of the innate immune system, are various soluble proteins, which play a critical role in destruction of invading pathogens directly or via engulfment of pathogens through the intermediate of phagocytosis. the diversity of opsonin profiles is under genetic influence and may be associated with variation in disease resistance. the aim of this study was to set up an assay to determine serum opsonophagocytic potential (opp) for chicken sera by flow cytometry and to evaluate ...201829920114
molecular characteristic and pathogenicity analysis of a virulent recombinant avain infectious bronchitis virus isolated in china.a virulent infectious bronchitis virus (ibv), designated as ck/ch/gd/qy16 (referred as qy16), was isolated from a diseased chicken farm in guangdong province, china, in 2016. the complete genome of the strain was sequenced and analyzed. the results show that the genome of qy16 consists of 27,670 nucleotides, excluding poly (a) tail, and that its genome organization is 5' utr-1a-1b-s-3a-3b-e-m-4b-4c-5a-5b-n-6b-3' utr-poly (a) tail. sequence comparison among qy16 and other ibv strains was conducte ...201829917155
rapid development and evaluation of a live-attenuated qx-like infectious bronchitis virus vaccine.infectious bronchitis (ib) is an acute, highly contagious disease, which causes economic losses to the poultry industry worldwide. to control the disease, biosecurity and vaccination are required. in the current research, we rapidly attenuated a qx-like ibv field strain zyy-2014 using passage in embryos at limiting dilution and tested the safety and efficacy of the attenuated chinese qx-like ibv strain zyyr-2014 in 1-day-old specific-pathogen-free (spf) chickens through spray route. our result r ...201829891352
preparation and protective efficacy of a chicken embryo kidney cell-attenuation gi-19/qx-like avian infectious bronchitis virus vaccine.avian infectious bronchitis (ib) is a highly contagious disease, and hazardous to the poultry industry. immune failure often occurs due to the emergence of new serotypes or field strains antigenically different from the vaccine strains. to prepare a candidate vaccine against the prevalent avian infectious bronchitis virus (ibv) in china, the gi-19/qx-like field isolate sczy3 was selected as the progenitor strain and attenuated via passaging in chicken embryo kidney (cek) cells for 100 times. the ...201829859801
differential innate immune responses induced by classical and variant infectious bronchitis viruses in specific pathogen free chicks.avian infectious bronchitis virus (ibv) continues to cause serious economic losses in global chicken production. concurrent circulation of both classic and variant ibvs have been identified in most parts of the world, raising major challenges to global prevention and control efforts. therefore, immunopathogenesis, particularly early host responses, needs to be better understood for effective control of diseases caused by different strains of ibvs. we investigated differing immunopathogenesis in ...201829751011
field efficacy of an attenuated infectious bronchitis variant 2 virus vaccine in commercial broiler chickens.egyptian poultry suffer from frequent respiratory disease outbreaks associated with infectious bronchitis virus (ibv) variant 2 strains (egy/varii). different vaccination programs using imported vaccines have failed to protect the flocks from field challenge. recent studies confirmed a successful protection using homologous strains as live attenuated vaccines. in this study, a newly developed live attenuated ib-var2 vaccine representing the gi-23 middle east ibv lineage was evaluated in day-old ...201829747397
mir-146a-5p promotes replication of infectious bronchitis virus by targeting irak2 and tnfrsf18.avian infectious bronchitis virus (ibv) is a coronavirus which infects chickens (gallus gallus) of all ages and causes significant economic losses to the poultry industry worldwide. the present study aims to analyze the mirnas related to pathogenicity of nephropathogenic ibvs. it was found that four mirnas (mir-1454, mir-3538, mir-146a-5p and mir-215-5p) were related to the infection of virulent nephropathogenic ibv with transcript per million (tpm) > 500 and more than a 2-fold alteration. in vi ...201829702211
effects of hypervariable regions in spike protein on pathogenicity, tropism, and serotypes of infectious bronchitis virus.to study the roles of hypervariable regions (hvrs) in receptor-binding subunit s1 of the spike protein, we manipulated the genome of the ibv beaudette strain using a reverse genetics system to construct seven recombinant strains by separately or simultaneously replacing the three hvrs of the beaudette strain with the corresponding fragments from a qx-like nephropathogenic isolate ck/ch/ldl/091022 from china. we characterized the growth properties of these recombinant ibvs in vero cells and embry ...201829684409
immunosensor based on antibody-functionalized mos2 for rapid detection of avian coronavirus on cotton thread.infectious bronchitis virus (ibv), an avian coronavirus, significantly affects the performance of both the egg-laying and meat-type birds causing the foremost of economic loss in poultry industry. this paper aims to develop a rapid, low-cost, and sensitive biosensor for ibv detection by using molybdenum disulfide (mos2). mos2 is a 2-d nanosheet which has strong high fluorescence-quenching ability when applied to a dye-labeled antibody (ab). in this paper, we developed an ab-functionalized mos2-b ...201832390783
inactivated infectious bronchitis virus vaccine encapsulated in chitosan nanoparticles induces mucosal immune responses and effective protection against challenge.avian infectious bronchitis virus (ibv) is one of the most important viral diseases of poultry. the mucosa of upper respiratory tract, specially the trachea, is the primary replication site for this virus. however, conventional inactivate ibv vaccines usually elicit reduced mucosal immune responses and local protection. thus, an inactivated ibv vaccine containing br-i genotype strain encapsulated in chitosan nanoparticles (ibv-cs) was produced by ionic gelation method to be administered by oculo ...201829653848
resiquimod enhances mucosal and systemic immunity against avian infectious bronchitis virus vaccine in the chicken.adjuvant enhancing mucosal immune response is preferred in controlling many pathogens at the portal of entry. earlier, we reported that a toll-like-receptor 7 (tlr7) agonist, resiquimod (r-848), stimulated the systemic immunity when adjuvanted with the inactivated newcastle disease virus vaccine in the chicken. here, we report the effect of r-848 when adjuvanted with live or inactivated avian infectious bronchitis virus (ibv) vaccines with special emphasis on mucosal immunity. specific pathogen ...201829635053
emergence of a genotype i variant of avian infectious bronchitis virus from northern part of india.infectious bronchitis virus (ibv) is one of the foremost causes of a persistent economic burden to poultry industries worldwide. ibv belongs to the genus gammacoronavirus within the family coronaviridae. the ibv infection leads to respiratory and nephrogenic symptoms in broiler chickens. in addition, its infection leads to reduced fertility and hatchability in layer birds. we determined the first complete genome sequence of a variant ibv from an outbreak in haryana state of the northern part of ...201829621536
genetic and pathologic characterization of a novel recombinant tc07-2-type avian infectious bronchitis virus.avian infectious bronchitis viruses (ibvs) with the tc07-2 genotype have spread rapidly in east asia since they were first reported in china in 2007. in 2015, an ibv with the tc07-2 genotype (designated krd1515) was isolated from layer chickens with severe respiratory symptoms in korea. in the present study, the full-length open reading frames of the spike (s) and nucleocapsid (n) genes of the virus were sequenced and analyzed. s1 gene phylogenetic analysis revealed that the krd1515 virus cluste ...201829620461
comparative evaluation of the pathogenicity of mycoplasma gallinaceum in chickens.mycoplasma gallinaceum is not among the most pathogenic mycoplasmas affecting poultry, but its continuous re-isolation from flocks in south africa displaying typical signs of mycoplasmosis prompted us to revisit its role in respiratory disease. specific-pathogen-free white leghorn chickens were co-challenged with either m. gallinaceum (mgc) and qx-like infectious bronchitis virus (ibv), or the more virulent mycoplasm gallisepticum (mg) and ibv. no clinical signs were observed apart from sneezing ...201829620458
isolation and characteristics of the arkansas-type infectious bronchitis virus in china.two infectious bronchitis virus (ibv) strains, designated as γcov/ck/china/i0712/11 (i0712/11) and γcov/ck/china/i0108/17 (i0108/17), were isolated from diseased chicken flocks in different provinces in china and genotyped as arkansas (ark)-type viruses with three other chinese ark field strains, the jilin vaccine strain, and the american ark- and ark dpi-like viruses. complete genomic sequence analysis and pairwise comparison of nucleotide sequences encoding the s1 subunit of the spike protein ...201829620453
development and evaluation of novel recombinant adenovirus-based vaccine candidates for infectious bronchitis virus and mycoplasma gallisepticum in chickens.avian infectious bronchitis caused by the infectious bronchitis virus (ibv), and mycoplasmosis caused by mycoplasma gallisepticum (mg) are two major respiratory diseases in chickens that have resulted in severe economic losses in the poultry industry. we constructed a recombinant adenovirus that simultaneously expresses the s1 spike glycoprotein of ibv and the tm-1 protein of mg (pbh-s1-tm-1-egfp). for comparison, we constructed two recombinant adenoviruses (pbh-s1-egfp and pbh-tm-1-egfp) that e ...201829115156
effect of restricted feed intake in broiler breeder hens on their stress levels and the growth and immunology of their offspring.the prenatal environment has been shown to have significant effects on the lifelong health of offspring in humans and other species. such effects have not been studied extensively in avian species but could prove important, especially in the case of severe feed restriction imposed on broiler breeder hens to prevent obesity and reduce rate of lay. feed restriction can potentially affect not only nutrient supply to the embryo but stress hormone levels within the hen. this study investigated the im ...201832704710
infectious bronchitis virus nonstructural protein 4 alone induces membrane pairing.positive-strand rna viruses, such as coronaviruses, induce cellular membrane rearrangements during replication to form replication organelles allowing for efficient viral rna synthesis. infectious bronchitis virus (ibv), a pathogenic avian gammacoronavirus of significant importance to the global poultry industry, has been shown to induce the formation of double membrane vesicles (dmvs), zippered endoplasmic reticulum (zer) and tethered vesicles, known as spherules. these membrane rearrangements ...201830200673
biological and molecular characterization of arkga: a novel arkansas serotype vaccine that is highly attenuated, efficacious, and protective against homologous challenge.almost all commercial poultry are vaccinated against avian coronavirus infectious bronchitis virus (ibv) using live attenuated vaccines mass administered by spray at day of hatch. although many different types of ibv vaccines are used successfully, the arkdpi serotype vaccine, when applied by spray, does not infect and replicate sufficiently to provide protection against homologous challenge. in this study, we examined a different ark vaccine strain (ark99), which is no longer used commercially ...201830197283
chiral zirconium quantum dots: a new class of nanocrystals for optical detection of coronavirus.a synthetic way of chiral zirconium quantum dots (zr qds) was presented for the first time using l(+)-ascorbic acid acts as a surface as well as chiral ligands. different spectroscopic and microscopic analysis was performed for thorough characterization of zr qds. as-synthesized qds exhibited fluorescence and circular dichroism properties, and the peaks were located at 412 nm and 352 nm, respectively. mtt assay was performed to test the cytotoxicity of the synthesized zr qds against rat brain gl ...201830186985
complete genome analysis of iranian is-1494 like avian infectious bronchitis virus.the nephropathogenic infectious bronchitis virus (ibv) strain is-1494 like (variant-2; gi-23) was first isolated in the middle east (1998). despite intensive vaccinations, is-1494 like ibvs are still circulating in iran (the dominant genotype) and spread to other countries. here, the full-length genome of this iranian is-1494 like ibv was (mahed) determined to understand its evolutionary relationships. the genome consists of 27,652 nucleotides, with mutations in most of the structural genes. thi ...201830159377
immune protection conferred by three commonly used commercial live attenuated vaccines against the prevalent local strains of avian infectious bronchitis virus in southern china.live attenuated vaccines are critical in the control of avian infectious bronchitis. it is necessary to know the protection conferred by commonly used commercial live vaccines. in this study, specific pathogen-free chicks were vaccinated with the commercial live vaccines h120, 4/91 and ldt3-a. blood samples were collected at weekly intervals for the detection of ibv-specific antibodies and quantification of cd4+ and cd8+ t lymphocytes. at 21 days post-inoculation the vaccinated birds were challe ...201830022779
the s2 subunit of infectious bronchitis virus beaudette is a determinant of cellular tropism.the spike (s) glycoprotein of the avian gammacoronavirus infectious bronchitis virus (ibv) is comprised of two subunits (s1 and s2), has a role in virulence in vivo, and is responsible for cellular tropism in vitro we have previously demonstrated that replacement of the s glycoprotein ectodomain from the avirulent beaudette strain of ibv with the corresponding region from the virulent m41-ck strain resulted in a recombinant virus, beaur-m41(s), with the in vitro cell tropism of m41-ck. the ibv b ...201830021894
identification of novel linear epitopes located in the infectious bronchitis virus spike s2 region.we identified novel linear epitopes on the infectious bronchitis virus (ibv) spike s2 region. the conformational structure of the ibv spike protein was predicted from a homologous protein, human coronavirus nl63 spike. although the obtained structure was incomplete, most of the ibv spike protein structure was predicted; the n-terminus of the s1 region could not be predicted due to its variability. in the model, the region located in the proximity of the fusion peptide appeared to be well conserv ...201829944406
using multinomial and space-time permutation models to understand the epidemiology of infectious bronchitis in california between 2008 and 2012.although infectious bronchitis virus (ibv) has been described as one of the most economically important viral respiratory diseases in poultry, there are few analyses of outbreaks that use spatial statistics. in order to better understand how the different genotypes of ibv behave spatially and temporally, we used geographic information system-based mapping coupled with spatial and spatial-temporal statistics to identify statistically significant clustering of multiple strains of infectious bronch ...201829944405
infectious bronchitis virus gel vaccination: evaluation of mass-like (b-48) and 793/b-like (1/96) vaccine kinetics after combined administration at 1 day of age.infectious bronchitis (ib) control has a strong impact on poultry farming, because of the necessary epidemiological knowledge for planning the best strategy, the optimal strain association, the priming and boosting interventions. broiler farming is even more problematic given the short and intense productive cycle, which requires an early onset of protection against most of the infectious threats, possibly with limited respiratory post-vaccination reactions that would have a direct impact on the ...201829897603
the adrp domain from a virulent strain of infectious bronchitis virus is not sufficient to confer a pathogenic phenotype to the attenuated beaudette strain.the replicase gene of the coronavirus infectious bronchitis virus (ibv) encodes 15 non-structural proteins (nsps). nsp 3 is a multi-functional protein containing a conserved adp-ribose-1″-phosphatase (adrp) domain. the crystal structures of the domain from two strains of ibv, m41 (virulent) and beaudette (avirulent), identified a key difference; m41 contains a conserved triple-glycine motif, whilst beaudette contains a glycine-to-serine mutation that is predicted to abolish adrp activity. althou ...201829893665
metagenomic of clinically diseased and healthy broiler affected with respiratory disease complex.in recent past, the respiratory infection has emerged as a great challenge to the poultry farmers. various pathogens including avian pneumovirus (apv), avian influenza virus (aiv), infectious bronchitis virus (ibv) and newcastle disease virus (ndv), avibacterium paragallinarum, ornithobacterium rhinotracheale (ort), mycoplasma synoviae (ms), mycoplasma gallisepticum (mg) and avian pathogenic escherichia coli (apec) are involved in the respiratory disease complex in birds [1], [2] (bradbury, 1984 ...201829892620
evaluation of full s1 gene sequencing of classical and variant infectious bronchitis viruses extracted from allantoic fluid and fta cards.sequence variability in the s1 gene determines the genotype of infectious bronchitis virus (ibv) strains. a single rt-pcr assay was developed to amplify and sequence the full s1 gene for six classical and variant ibvs (m41, d274, 793b, is/885/00, is/1494/06 and q1) enriched in allantoic fluid (af) or the same af inoculated onto flinders technology association (fta) cards. representative strains from each genotype were grown in specific-pathogen-free eggs and rna was extracted from af. full s1 ge ...201829712443
coronavirus infectious bronchitis virus non-structural proteins 8 and 12 form stable complex independent of the non-translated regions of viral rna and other viral proteins.the cleavage products from coronavirus polyproteins, known as the non-structural proteins (nsps), are believed to make up the major components of the viral replication/transcription complex. in this study, several nsps encoded by avian gammacoronavirus infectious bronchitis virus (ibv) were screened for rna-binding activity and interaction with its rna-dependent rna polymerase, nsp12. nsp2, nsp5, nsp8, nsp9 and nsp10 were found to bind to untranslated regions (utrs), while nsp8 was confirmed to ...201829035788
identification of n-linked glycosylation sites in the spike protein and their functional impact on the replication and infectivity of coronavirus infectious bronchitis virus in cell culture.spike (s) glycoprotein on the viral envelope is the main determinant of infectivity. the s protein of coronavirus infectious bronchitis virus (ibv) contains 29 putative asparagine(n)-linked glycosylation sites. these post-translational modifications may assist in protein folding and play important roles in the functionality of s protein. in this study, we used bioinformatics tools to predict n-linked glycosylation sites and to analyze their distribution in ibv strains and variants. among these s ...201829035787
detection of different genotypes of infectious bronchitis virus and of infectious bursal disease virus in european broilers during an epidemiological study in 2013 and the consequences for the diagnostic approach.to gather recent data regarding the infectious bronchitis (ib) and infectious bursal disease (ibd) situation in europe, a large-scale field epidemiological survey using diagnostic samples has been implemented in 2013 for about six months in several european countries: france, germany, greece, italy, the netherlands, poland, portugal, the republic of ireland, spain and the uk. in 234 flocks that were sampled, strains from 10 different ibv genotypes were detected: the 793b genotype was detected mo ...201828972403
evaluation of 793/b-like and mass-like vaccine strain kinetics in experimental and field conditions by real-time rt-pcr quantification.infectious bronchitis virus (ibv) is a great economic burden both for productive losses and costs of the control strategies. many different vaccination protocols are applied in the same region and even in consecutive cycles on the same farm in order to find the perfect balance between costs and benefits. in northern italy, the usual second vaccination is more and more often moved up to the chick's first d of life. the second strain administration together with the common mass priming by spray at ...201829077954
characterization of the complete genome, antigenicity, pathogenicity, tissue tropism, and shedding of a recombinant avian infectious bronchitis virus with a ck/ch/ljl/140901-like backbone and an s2 fragment from a 4/91-like virus.in this study, we isolated an infectious bronchitis virus, designated i1101/16, from broiler breeders in china. analysis of the s1 gene showed that isolate i1101/16 was genetically close to strain ck/ch/ljl/140901, which belongs to the tw i genotype (also known as lineage gi-7 based on the recent ibv classification), however the s2 gene showed genetic diversity comparing to that of s1 gene. comparison of the genomic sequences showed that the genome of isolate i1101/16 was similar to that of stra ...201829141204
supplementing dietary rosemary (rosmarinus officinalis l.) powder and vitamin e in broiler chickens: evaluation of humoral immune response, lymphoid organs, and blood proteins.the aim of the present study was to evaluate the effect rosemary (rosmarinus officinalis l.) powder (rp) and vitamin e (ve) at different levels on humoral immunity of broilers during a 42-day production cycle. a total of 270 1-day-old male chicks were assigned to nine groups with three replicates of ten birds each, and diets were supplemented with 0, 0.5, or 1.0% rp and 0, 100, or 200 mg/kg ve, respectively. commercial-inactivated vaccines against avian influenza (ai) and newcastle disease (nd) ...201829330815
induction of innate immune response following introduction of infectious bronchitis virus (ibv) in the trachea and renal tissues of chickens.infectious bronchitis (ib) is a highly contagious respiratory disease of chickens, which is caused by the infectious bronchitis virus (ibv). the innate immune response is crucial for antiviral infections and revealing the pathogenic mechanisms of ibv. in this study, we presents an evaluation of interferon (i, ii and iii ifns) in renal and tracheal samples from chickens experimentally infected previously vaccinated or not. the results suggest differential expression of chicken interferon, among t ...201829330060
differential effects of experimental hyperthyroidism on declined immunity of broiler chicken.thyroid hormones (ths) are involved in the development of lymphoid organs and regulation of immune function in birds. however, their role as an immune-modulator in the hyperthyroid state is still debatable. to explore the interrelationship of thyroxine (t4) and the immune system, chicks were divided into three groups. group i was comprised of control birds, who received the basal diet while group ii and iii were given diets supplemented with 5 μg and 10 μg thyroxine/kg feed, respectively, from 1 ...201829327786
pathogenicity differences between qx-like and mass-type infectious bronchitis viruses.infectious bronchitis is a highly contagious, acute viral respiratory disease of chickens, caused by infectious bronchitis virus (ibv). in recent years, the isolation rate of qx-like ibv has increased in the world. to clarify this phenomenon and better understand the pathogenicity of qx-like ibv, we examined differences in pathogenicity between two ibv strains, sd and m41, which belong to qx-like and mass-type ibv, respectively. sd strain was more virulent in 3-week-old specific-pathogen-free ch ...201829291996
a review of eight high-priority, economically important viral pathogens of poultry within the caribbean region.viral pathogens cause devastating economic losses in poultry industries worldwide. the caribbean region, which boasts some of the highest rates of poultry consumption in the world, is no exception. this review summarizes evidence for the circulation and spread of eight high-priority, economically important poultry viruses across the caribbean region. avian influenza virus (aiv), infectious bronchitis virus (ibv), newcastle disease virus (ndv), infectious laryngotracheitis virus (iltv), avian met ...201829373488
serological evidence for eight globally important poultry viruses in trinidad & tobago.viruses affecting poultry cause significant levels of disease leading to severe economic losses among poultry farmers worldwide. the americas region continues to be vulnerable to the spread of poultry viruses across the continents and caribbean island chains. in trinidad and tobago (t&t) there is limited information on the viruses circulating in poultry. many flock are vulnerable to infection and there are occasional outbreaks of disease resulting in high levels of morbidity and mortality. this ...201829290303
a multiplex real-time rt-pcr for simultaneous detection of four most common avian respiratory viruses.a one-step multiplex real-time reverse transcription-pcr (rrt-pcr) assay was developed for simultaneous detection and quantification of four avian respiratory viruses: avian influenza virus (aiv), infectious bronchitis virus (ibv), newcastle disease virus (ndv) and infectious laryngotracheitis virus (iltv). in comparison with the singleplex rrt-pcr, the specificity, the sensitivity and the reproducibility of the new assay were evaluated and validated using 70 clinical samples. the optimal cutoff ...201829223788
development of an xtag-multiplex pcr array for the detection of four avian respiratory viruses.acute respiratory tract infections are of paramount importance in the poultry industry. we developed an xtag bead assay for the simultaneous detection and discrimination of avian influenza virus (aiv), newcastle disease virus (ndv), infectious bronchitis virus (ibv) and infectious laryngotracheitis virus (iltv). the assay lacked nonspecific reactions with other common avian viruses and the limit of detection was 6.75 × 102- 3.52 × 103copies/μl. we examined 60 clinical specimens and found 18 posi ...201829054443
efficacy of h120 and ma5 avian infectious bronchitis vaccines in early challenge against qx strain.infectious bronchitis (ib) is a highly infectious avian pathogen, which affects the respiratory tract, gut, reproductive system, and kidney of chicks of all ages. many different serotypes of ib virus (ibv) are recognized which cause different clinical manifestations. according to the antigenic differences, different serotypes of the virus do not cross-protect. massachusetts serotype induces the best cross-protection against other serotypes. recently, the ibv qx strain has been detected in iran. ...201829607371
enteric virus diversity examined by molecular methods in brazilian poultry flocks.enteric viruses play an important role in the brazilian poultry industry due to the economic impact of resulting low yields of broilers, layers, and breeders. the most common enteric viruses affecting commercial flocks in brazil include fowl adenovirus of group i (fadv-i), chicken parvovirus (chpv), chicken astrovirus (castv), avian nephritis virus (anv), infectious bronchitis virus (ibv), avian reovirus (areo), and avian rotavirus (artv). the aim of this study was to identify single and multipl ...201829596389
coronavirus infection retards the development of the cortico-medullary capillary network in the bursa of fabricius of chicken.coronavirus infection delays the development of the cortico-medullary (cm) capillary network which results in retarded development of bursal follicles. the smaller size of the medulla in the coronavirus-infected birds may lead to a lower number of b lymphocytes and bursal secretory dendritic cells, which negatively affects the reactivity and efficacy of the immune system. contrary to the wild-type infectious bronchitis virus (ibv) strain, infection induced by h120 vaccine virus exerts only a mod ...201829580080
phylodynamic analysis and molecular diversity of the avian infectious bronchitis virus of chickens in brazil.avian infectious bronchitis virus (ibv) is the etiological agent of a highly contagious disease, which results in severe economic losses to the poultry industry. the spike protein (s1 subunit) is responsible for the molecular diversity of the virus and many sero/genotypes are described around the world. recently a new standardized classification of the ibv molecular diversity was conducted, based on phylogenetic analysis of the s1 gene sequences sampled worldwide. brazil is one of the biggest po ...201829574164
coronavirus s protein-induced fusion is blocked prior to hemifusion by abl kinase inhibitors.enveloped viruses gain entry into host cells by fusing with cellular membranes, a step that is required for virus replication. coronaviruses, including the severe acute respiratory syndrome coronavirus (sars-cov), middle east respiratory syndrome coronavirus (mers-cov) and infectious bronchitis virus (ibv), fuse at the plasma membrane or use receptor-mediated endocytosis and fuse with endosomes, depending on the cell or tissue type. the virus spike (s) protein mediates fusion with the host cell ...201829557770
avian coronavirus isolated from a pigeon sample induced clinical disease, tracheal ciliostasis, and a high humoral response in day-old chicks.the detection of avian coronaviruses (avcov) in wild birds and the emergence of new avcov have increased in the past few years. in the present study, the pathogenicity of three avcov isolates was investigated in day-old chicks. one avcov isolated from a pigeon, which clustered with the massachusetts vaccine serotype, and two avcov isolated from chickens, which grouped with a brazilian genotype lineage, were used. clinical signs, gross lesions, histopathological changes, ciliary activity, viral r ...201829517348
attenuation, safety, and efficacy of a qx-like infectious bronchitis virus serotype vaccine.avian infectious bronchitis (ib) is a highly contagious disease caused by avian infectious bronchitis virus (ibv), which is a considerable economic threat to the poultry industry. qx-like ibv strains have increasingly emerged in china in recent years. hence, development of a specific vaccine to guard against their potential threat is important. in this study, we sought to develop an attenuated vaccine strain. first, attenuated qx-like ibv strain sz130 was created by continuous passage in chicken ...201829496346
rapid detection and differentiation of avian infectious bronchitis virus: an application of mass genotype by melting temperature analysis in rt-qpcr using sybr green i.a method based on melting temperature analysis of hypervariable regions (hvr) of s1 gene within a rt-qpcr was developed to detect different genotypes of avian infectious bronchitis virus (ibv) and identify the mass genotype. the method was able to rapidly identify the mass genotype among ibv field isolates, vaccine attenuated strains and reference m41 strain in allantoic liquid and also directly in tissues. the rt-qpcr developed detected the virus in both tracheal and pulmonary samples from m41- ...201829491226
innate antiviral immune response against infectious bronchitis virus and involvement of prostaglandin e2 in the uterine mucosa of laying hens.infectious bronchitis virus (ibv) is an enveloped rna virus that causes deformities in eggshells. the aim of this study was to investigate the innate immune response to ibv, and to determine whether prostaglandin (pg) e2, which is synthesized during inflammation, is involved in the innate immune response in the uterine mucosa. the effects of intra-oviductal inoculation with attenuated ibv (aibv) on the expression of viral rna recognition receptors and innate antiviral factors were examined by re ...201829407895
disclosing respiratory coinfections: a broad-range panel assay for avian respiratory pathogens on a nanofluidic pcr platform.respiratory syndromes (rs) are among the most significant pathological conditions in food animals and are caused by complex coactions of pathogens and environmental factors. in poultry, low pathogenic avian influenza a viruses, metapneumoviruses, infectious bronchitis virus, infectious laryngotracheitis virus, mycoplasma spp. escherichia coli and/or ornithobacterium rhinotracheale (ort) in turkeys, are considered as key co-infectious agents of respiratory syndromes. aspergillus sp., pasteurella ...201829350071
mitochondrial bioenergy alterations in avian hd11 macrophages infected with infectious bronchitis virus.to establish an association between mitochondrial dysfunction and apoptosis following infectious bronchitis virus (ibv) infection, hd11 avian macrophage cells were infected with the massachusetts 41 (m41) strain. our results show that the m41 strain of ibv induced cytopathic effects followed by the release of new viral particles. elevated numbers of apoptotic cells were observed at 24, 48 and 72 h post-infection (p.i.). viral infection was associated with mitochondrial membrane depolarization an ...201829302792
avian metapneumovirus circulation in italian broiler farms.with increasing frequency, avian metapneumovirus (ampv) is reported to induce respiratory signs in chickens. an adequate knowledge of current ampv prevalence among italian broilers is lacking, with little information available on its economical and health impact on the poultry industry. in order to collect preliminary data on the epidemiological context of ampv in broiler flocks, a survey was performed in areas of northern italy with high poultry density from 2014 to 2016. upper respiratory trac ...201829253264
assessment of mycoplasma gallisepticum vaccine efficacy in a co-infection challenge model with qx-like infectious bronchitis virus.mycoplasma gallisepticum (mg) is the primary cause of chronic respiratory disease in poultry. we investigated the protective efficacy of the live attenuated ts-11 and 6/85 mg vaccines against a local mg strain, and in order to enhance symptoms and mimic a typical field situation, we co-infected birds with a virulent strain of qx-like infectious bronchitis virus (ibv). both vaccines showed similar ability to protect infected chickens from clinical signs, although ts-11 performed slightly better. ...201829451010
induction of innate host responses characterized by production of interleukin (il)-1β and recruitment of macrophages to the respiratory tract of chickens following infection with infectious bronchitis virus (ibv).infectious bronchitis virus (ibv) infection is a major cause of economic losses to the poultry industry. due to limitations in current control measures, alternative approaches, based on thorough understanding of the host responses are required. as one of the key component of the avian immune system, the innate immune system has a crucial role in limiting virus replication at the initial stage of the infection. as parts of the innate host response, macrophages and cytokines, such as interleukin ( ...201829426399
recombinant live attenuated avian coronavirus vaccines with deletions in the accessory genes 3ab and/or 5ab protect against infectious bronchitis in chickens.avian coronavirus infectious bronchitis virus (ibv) is a respiratory pathogen of chickens, causing severe economic losses in poultry industry worldwide. live attenuated viruses are widely used in both the broiler and layer industry because of their efficacy and ability to be mass applied. recently, we established a novel reverse genetics system based on targeted rna recombination to manipulate the genome of ibv strain h52. here we explore the possibilities to attenuate ibv in a rational way in o ...201829366709
detection of antibodies to seven priority pathogens in backyard poultry in trinidad, west indies.backyard poultry farms in trinidad and tobago (t&t) play a vital role in providing food and income for rural communities. there is currently no information on the presence and circulation of pathogens in backyard poultry farms in t&t, and little is known in relation to the potential risks of spread of these pathogens to the commercial poultry sector. in order to address this, serum samples were collected from 41 chickens on five backyard farms taken from selected locations in trinidad. s ...201829361703
molecular characterization of whole genome sequence of infectious bronchitis virus 624i genotype confirms the close relationship with q1 genotype.infectious bronchitis virus (ibv) genotype q1 was detected for the first time in china in 1996, and then spread worldwide. the first report of q1 genotype in italy occurred in 2011 and a deep molecular investigation of a q1 isolated in italy in 2013 has led to speculation regarding the origin of this genotype. phylogenetic analysis of the s1 sequence of a q1 italian strain revealed a close relationship with sequences of the 624i strains circulating in italy in the early 1990s and this led to the ...201930126059
antigenic and pathogenic characteristics of qx-type avian infectious bronchitis virus strains isolated in southwestern china.the qx-type avian infectious bronchitis virus (ibv) is still a prevalent genotype in southwestern china. to analyze the antigenicity and pathogenicity characteristics of the dominant genotype strains (qx-type), s1 gene sequence analysis, virus cross-neutralization tests, and pathogenicity test of eight qx-type ibv isolates were conducted. sequence analysis showed that the nucleotide homology between the eight strains was high, but distantly related to h120 and 4/91 vaccine strains. cross-neutral ...201931847269
infections and pathology of free-roaming backyard chickens on st. kitts, west indies.free-roaming chickens on caribbean islands are important sentinels for local avian diseases and those introduced by birds migrating through the americas. we studied 81 apparently healthy unvaccinated free-roaming chickens from 9 parishes on st. kitts, an eastern caribbean island. using commercial elisas, no chickens had antibodies against avian influenza virus, west nile virus, or salmonella enteritidis, although seropositivity was high to infectious bursal disease virus (86%), infectious bronch ...201930973088
molecular survey and interaction of common respiratory pathogens in chicken flocks (field perspective).the present study was designed for the detection of the most prevalent respiratory infections in chicken flocks and clarifying their interaction and impact on flock health.201932095050
isolation and characterization of avian coronavirus from healthy eclectus parrots (eclectus roratus) from indonesia.avian coronavirus has a wide range of hosts, from chickens and turkeys to wild birds. this virus causes an economically and, possibly, environmentally, important loss in the poultry industry. therefore, research into the avian coronavirus in various species of birds is required. the eclectus parrot (eclectus roratus) is an endemic bird to indonesia and northern australia and often kept as pets. at present, there has been limited information about avian coronavirus infection among birds. this stu ...201932009759
attenuation and amino acid changes in infectious bronchitis virus iranian 793/b serotype during serial passaging in embryonated chicken eggs.the use of live attenuated vaccine (lav) is the main method for controlling infectious bronchitis (ib). it is advisable to develop a lav using a dominant serotype in the region in the case of vaccine failure. since 793/b serotype is one of the most predominant circulating ib viruses in iran, attenuation of three iranian 793/b isolates (ir/773/2001, ir/794/2002 and ir/520/2002) was done by serial passaging in specific pathogen free (spf) embryonated chicken eggs up to 90 passages to assess the de ...201931802683
pathogenicity of a qx-like strain of infectious bronchitis virus and effects of accessory proteins 3a and 3b in chickens.qx-like genotype infectious bronchitis virus (ibv) has become prevalent in recent years. few studies have reported the effects of accessory proteins 3a and 3b on pathogenicity in vivo. we developed a reverse genetics system to manipulate the genome of a qx-like ibv strain ibyz. recombinant viruses ribyz-scaug3a, ribyz-scaug3b and ribyz-scaug3ab were generated. these viruses do not express the accessory proteins 3a, 3b, or 3ab due to a mutation in the aug start codons. in spf embryonated eggs, th ...201931767070
delmarva (dmv/1639) infectious bronchitis virus (ibv) variants isolated in eastern canada show evidence of recombination.infectious bronchitis virus (ibv) infection in chickens can lead to an economically important disease, namely, infectious bronchitis (ib). new ibv variants are continuously emerging, which complicates vaccination-based ib control. in this study, five ibvs were isolated from clinical samples submitted to a diagnostic laboratory in ontario, canada, and subjected to detailed molecular characterization. analysis of the spike (s)1 gene showed that these five ibvs were highly related to the delmarva ( ...201931766215
a multi-omics study of chicken infected by nephropathogenic infectious bronchitis virus.chicken gout resulting from nephropathogenic infectious bronchitis virus (nibv) has become a serious kidney disease problem in chicken worldwide with alterations of the metabolic phenotypes in multiple metabolic pathways. to investigate the mechanisms in chicken responding to nibv infection, we examined the global transcriptomic and metabolomic profiles of the chicken's kidney using rna-seq and gc-tof/ms, respectively. furthermore, we analyzed the alterations in cecal microorganism composition i ...201931744152
antiviral activity against infectious bronchitis virus and bioactive components of hypericum perforatum l.hypericum perforatum l., also known as saint john's wort, has been well studied for its chemical composition and pharmacological activity. in this study, the antiviral activities of h. perforatum on infectious bronchitis virus (ibv) were evaluated in vitro and in vivo for the first time. the results of in vitro experiments confirmed that the antiviral component of h. perforatum was ethyl acetate extraction section (hpe), and results showed that treatment with hpe significantly reduced the relati ...201931736754
characterization of an outbreak of infectious coryza (avibacterium paragallinarum) in commercial chickens in central california.in 2017, the turlock branch of the california animal health & food safety laboratory system received a significant increase in infectious coryza (ic) necropsy cases, with a total of 54 submissions originating from commercial broilers (n = 40), commercial layers (n = 11), and backyard chickens (n = 3). layer flocks positive for ic were distributed within the adjacent counties of merced and stanislaus, while broiler flocks were concentrated within merced county. the backyard flocks were located in ...201931967433
evaluation of bacteriophage efficacy in reducing the impact of single and mixed infections with escherichia coli and infectious bronchitis in chickens.infectious bronchitis virus (ibv) represents a major threat to poultry production worldwide particularly when complicated with bacterial infection. in the present study samples were collected from forty broiler farms with respiratory manifestations to characterize ibv and e. coli. bacteriophages were isolated and enriched from sampled farms to study its efficacy to control single and mixed infections with e. coli and ibv in vivo. twelve out of forty farms were positive for ibv. phylogenetic anal ...201931839902
a recombinant la sota vaccine strain expressing multiple epitopes of infectious bronchitis virus (ibv) protects specific pathogen-free (spf) chickens against ibv and ndv challenges.infectious bronchitis (ib) and newcastle disease (nd) are two major infectious diseases that are a threat to the domestic poultry industry. in this study, we successfully generated a recombinant lasota candidate vaccine strain, rndv-ibv-t/b, which expresses a short, synthetic, previously identified ibv s1 multi-epitope cassette using the reverse genetic system. the recombinant virus was propagated in nine-day-old embryonated chicken eggs for 20 passages and genetic stability was confirmed by who ...201931683905
protective effects of hypericin against infectious bronchitis virus induced apoptosis and reactive oxygen species in chicken embryo kidney cells.avian infectious bronchitis virus (ibv), a coronavirus, causes infectious bronchitis leading to enormous economic loss in the poultry industry worldwide. hypericin (hy) is an excellent compound that has been investigated in antiviral, antineoplastic, and antidepressant. to investigate the inhibition effect of hy on ibv infection in chicken embryo kidney (cek) cells, 3 different experimental designs: pre-treatment of cells prior to ibv infection, direct treatment of ibv-infected cells, and pre-tr ...201931399732
emergence and genetic analysis of variant pathogenic 4/91 (serotype 793/b) infectious bronchitis virus in egypt during 2019.infectious bronchitis virus (ibv) affects both vaccinated and unvaccinated flocks worldwide, with a significant impact on the poultry industry. the aim of the present study is to characterize an emerging variant pathogenic ibv originating from field outbreaks in vaccinated egyptian layer flock. samples were collected from disease-suspected flock with a history of administration of live and inactivated ibv vaccines (ma5 type). virus propagation in embryonated chicken eggs (eces), after three succ ...201931372921
a seminested rt-pcr for molecular genotyping of the brazilian br-i infectious bronchitis virus strain (gi-11).infectious bronchitis (ib) is one of the avian diseases with the greatest impact on poultry farming worldwide. in brazil, strain br-i (gi-11) is the most prevalent in poultry flocks. the present study aimed to develop a seminested rt-pcr assay specific for the diagnosis of br-i ibv in brazilian samples, targeting subunit 1 of the s gene. the detection limit of this assay was 10 copies of the ibv genome. in this study, 62.24% of 572 organ pools from the 5 regions of brazil tested positive in a 3' ...201931365883
microarray analysis of infectious bronchitis virus infection of chicken primary dendritic cells.avian infectious bronchitis virus (ibv) is a major respiratory disease-causing agent in birds that leads to significant losses. dendritic cells (dcs) are specialised cells responsible for sampling antigens and presenting them to t cells, which also play an essential role in recognising and neutralising viruses. recent studies have suggested that non-coding rnas may regulate the functional program of dcs. expression of host non-coding rnas changes markedly during infectious bronchitis virus infec ...201931286855
molecular and biological characteristics of the infectious bronchitis virus tc07-2/gvi-1 lineage isolated in china.in the present study, a thorough comparison of the infectious bronchitis virus (ibv) tc07-2/gvi-1 linage was conducted by comparing the s1 gene sequences of gvi-1 viruses with those of viruses representing the established genotypes and lineages. ibv gvi-1 strains were found to be closely genetically related to each other, irrespective of where the viruses were isolated, and differed from other known ibv genotypes and lineages; thus, it was confirmed that gvi represents a novel genotype. however, ...201931255833
effects of chicken mhc haplotype on resistance to distantly related infectious bronchitis viruses.the major histocompatibility complex (mhc) b locus of chickens has been associated with resistance to different viral diseases. we previously provided evidence that chicken lines expressing mhc haplotypes b2 and b19 exhibit different resistance to a challenge with infectious bronchitis virus (ibv) massachusetts 41 (m41). in the current study, we attempted to determine if those differences were true for genetically diverse ib viruses, i.e., ibv m41 and arkansas-delmarva poultry industry (arkdpi). ...201931251532
infectious bronchitis virus vaccination at day 1 of age further limits cross protection.cross-protection and immune responses elicited by infectious bronchitis virus (ibv) vaccination on day 1 of age or at later time points were examined. specific-pathogen-free chickens were vaccinated with a massachusetts-type vaccine and heterologous challenge was performed with an arkansas (ark) -type virulent strain. in trial 1, chickens vaccinated on day 1 or day 10 of age were challenged 21 days after vaccination. analysis of tracheal histopathology and viral load demonstrated less cross prot ...201931251531
early vaccination of chickens induces suboptimal immunity against infectious bronchitis virus.infectious bronchitis virus (ibv) is highly prevalent in broiler chickens despite extensive vaccination commonly conducted early after hatch. the effects of early vaccination on immune responses were further investigated in chickens primed at increasing ages, followed by booster vaccination with an attenuated arkansas (ark) delmarva poultry industry-type vaccine. results show that vaccination on day 1 of age elicits significantly lower systemic and mucosal antibody responses compared with vaccin ...201931251518
molecular characteristics and pathogenicity analysis of qx-like avian infectious bronchitis virus isolated in china in 2017 and 2018.proportions of qx-like genotype infectious bronchitis virus (ibv) isolates have increased over time. here, to better understand the epidemiology and pathogenicity of ibv in china and control the spread of infectious bronchitis (ib), we conducted sequence analyses and examined the pathogenicity of 5 field isolates from diseased flocks in 2017 and 2018. sequence analyses revealed that all the 5 strains, as well as many recent field isolates from other researchers, belonged to the qx-like ibv genot ...201931222258
combined adjuvant effect of ginseng stem-leaf saponins and selenium on immune responses to a live bivalent vaccine of newcastle disease virus and infectious bronchitis virus in chickens.vaccination with a live bivalent vaccine of newcastle disease virus (ndv) and infectious bronchitis virus (ibv) is a routine practice in poultry industry in china. this study was designed to evaluate ginseng stem-leaf saponins (gsls) in combination with selenium (se) for their adjuvant effect on the immune response to vaccination against ndv and ibv in chickens. a live bivalent vaccine of ndv and ibv was diluted in saline solution containing gsls or se or both and used to immunize chickens via a ...201931220864
cross-species transmission of poultry pathogens in backyard farms: ducks as carriers of chicken viruses.in backyard farms of lao people's democratic republic, mixed-species rearing of poultry is a breeding-ground for cross-species transmission. here, the epidemiology of viruses circulating among backyard poultry in vientiane province was assessed to guide future control strategies. oral/tracheal and cloacal swabs, collected from 605 poultry (308 ducks, 297 chickens) between 2011 and 2015, were screened by pcr for newcastle disease virus (ndv), coronavirus (cov) and chicken anaemia virus (cav). chi ...201931199168
combination of tlr2 and tlr3 agonists derepress infectious bursal disease virus vaccine-induced immunosuppression in the chicken.live intermediate plus infectious bursal disease virus (ibdv) vaccines (hot vaccines) are used for protection against the virulent ibdv strains in young chickens. we evaluated the potential of toll-like receptor (tlr) agonists to alleviate hot vaccine-induced immunosuppression. the combination of pam3csk4 and poly i:c synergistically upregulated ifn-β, ifn-γ, il-12, il-4, and il-13 transcripts and cross-inhibited il-1β, il-10, and inos transcripts in the chicken peripheral blood mononuclear cell ...201931160675
avian influenza h9n2 subtype in ghana: virus characterization and evidence of co-infection.between november 2017 and february 2018, ghanaian poultry producers reported to animal health authorities a dramatic increase in mortality rate and a relevant drop in egg production in several layer hen farms. laboratory investigations revealed that the farms had been infected by the h9n2 influenza subtype. virological and molecular characterization of the viruses identified in ghana is described here for the first time. whole genome analysis showed that the viruses belong to the g1-lineage and ...201931142135
progress on chicken t cell immunity to viruses.avian virus infection remains one of the most important threats to the poultry industry. pathogens such as avian influenza virus (aiv), avian infectious bronchitis virus (ibv), and infectious bursal disease virus (ibdv) are normally controlled by antibodies specific for surface proteins and cellular immune responses. however, standard vaccines aimed at inducing neutralizing antibodies must be administered annually and can be rendered ineffective because immune-selective pressure results in the c ...201931101935
infectious bronchitis virus from chickens in al-hasa, saudi arabia 2015-2016.this study aimed to isolate some of the currently circulating infectious bronchitis virus (ibv) strains from some broiler chicken farms in al-hasa and to do some molecular characteristics of these strains.201931089313
occurrence of infectious bronchitis in layer birds in plateau state, north central nigeria.a flock of 54 wk-old layer birds exhibiting signs of respiratory distress, greenish diarrhea, and drop in egg production was investigated. a marked drop in egg production (55%) was recorded with eggs appearing white and soft-shelled. mortality was in the range of 1%-2% with post-mortem lesions revealing cloudy air sacs, frothy, and congested lungs. viral rna was extracted from pooled tissue samples (trachea, lungs, spleen, and liver) and tested for avian influenza virus (aiv), newcastle disease ...201931086770
spotlight on avian pathology: infectious bronchitis virus.infectious bronchitis is a highly infectious disease of the domestic chicken of all ages and type, affecting the respiratory, renal and reproductive systems. secondary bacterial infections are common and have a serious economic and welfare impact. many genotypic and serotypic variants of infectious bronchitis virus (ibv) exist worldwide, making diagnosis difficult, and challenging control strategies. vaccination, requiring the use of both live-attenuated and inactivated vaccines, is needed to co ...201931084356
pathogenicity of a gi-22 genotype infectious bronchitis virus isolated in china and protection against it afforded by gi-19 vaccine.avian infectious bronchitis (ib) is a globally circulating bird disease caused by infectious bronchitis virus (ibv). in china, the most prevalent ibv genotype is gi-19/qx-like because the protective efficiency of the classical ibv vaccine is low, and new gi-19 vaccines are under development. in 2018, a gi-22 genotype strain ck/ch/lgd/2018 (abbreviated 'lgd') was isolated in northern china, which caused 10%-30% morality in h120-vaccinated chickens. a phylogenetic analysis showed that this new iso ...201931082454
s gene and 5a accessory gene are responsible for the attenuation of virulent infectious bronchitis coronavirus.to explore the critical genes associated with infectious bronchitis virus (ibv) virulence, we compared the genome sequences of virulent yn strain and its attenuated strain ayn. accumulation of mutations in the s gene and the accessory gene 5a were observed, suggesting a potential role in the loss of viral pathogenicity. two recombinant ibvs (ribvs) with replacement of the s gene or 5a with corresponding regions from ayn were rescued to verify this speculation. embryo mortality time/rate showed t ...201931078931
a novel immunochromatographic strip for antigen detection of avian infectious bronchitis virus.avian infectious bronchitis virus (ibv) causes considerable economic losses in the poultry industry worldwide, including taiwan. ibv is among the most important pathogens in chickens, and it spreads rapidly among flocks. in addition to dozens of known serotypes, new viral variants have emerged due to the viral evolution and antigenic variation in ibvs. therefore, the development of a sensitive, specific, and easily performed assay is crucial for the rapid detection and surveillance of ibv infect ...201931064083
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