| evolution of infectious bronchitis virus in taiwan: positively selected sites in the nucleocapsid protein and their effects on rna-binding activity. | rna recombination has been shown to underlie the sporadic emergence of new variants of coronavirus, including the infectious bronchitis virus (ibv), a highly contagious avian pathogen. we have demonstrated that rna recombination can give rise to a new viral population, supported by the finding that most isolated taiwanese (tw) ibvs, similar to chinese (ch) ibvs, exhibit a genetic rearrangement with the american (us) ibv at the 5' end of the nucleocapsid (n) gene. here, we further show that posit ... | 2013 | 23159091 |
| a type-specific blocking elisa for the detection of infectious bronchitis virus antibody. | infectious bronchitis virus (ibv) infection has been a major threat to the poultry industry worldwide. current commercially available elisa kits detect group-specific antibodies; however, to understand the status of field infection, a monoclonal antibody (mab) blocking elisa (b-elisa) against local ibvs was developed. the selected mab showed specificity to taiwan ibv strains but had no cross-reactivity with the vaccine strain h120. using the hemagglutination inhibition (hi) test as a standard, t ... | 2010 | 21192982 |
| 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 ... | 2009 | 19100792 |
| s1 and n gene analysis of avian infectious bronchitis viruses in taiwan. | the disease caused by infectious bronchitis virus (ibv) produces great economic for the poultry industry. the purpose of this study is to investigate the molecular epidemiology of ibv in taiwan. an old ibv strain isolated in 1964 and another 31 strains isolated from 1991 to 2003 were selected for n-terminal s1 gene analysis. based on their phylogenetic tree, 13 strains were selected for sequencing the entire s1 and partial nucleocapsid (n) genes. the results indicated that taiwanese ibv strains ... | 2004 | 15529980 |
| complete nucleotide sequences of s1 and n genes of infectious bronchitis virus isolated in japan and taiwan. | the complete nucleotide sequences of the s1 and n genes of three japanese and one taiwanese field strains of ibv are reported. these japanese strains were found to have s1 sequences most similar to those of australian strains and n sequences most similar to those of north american strains. this result suggested that these japanese strains might all be recombinant viruses derived from recombination of australia- and north america-related viruses. moreover, the s1 proteins of all these japanese an ... | 2004 | 15187369 |
| detection of infectious bronchitis virus by multiplex polymerase chain reaction and sequence analysis. | a multiplex reverse transcription-polymerase chain reaction (rt-pcr) was developed to amplify the s1 and s2 genes of vaccine and recent taiwanese isolates of infectious bronchitis virus (ibv). dna fragments of 228 and 400 base pairs in length were amplified among ibv isolates in multiplex pcr, suggesting that there were no apparent deletions or insertions in these regions. no pcr products were amplified from unrelated avian viruses and negative controls. the results suggested that multiplex pcr ... | 2003 | 12668265 |
| genetic grouping for the isolates of avian infectious bronchitis virus in taiwan. | in order to differentiate recent isolates of avian infectious bronchitis virus (ibv) in taiwan, polymerase chain reaction (pcr), restriction fragment length polymorphism (rflp), and direct sequencing methods were used to type 25 ibv taiwan isolates. two conserved sequences that flank the hypervariable region i (hvr i) in the n-terminus of s1 protein gene were chosen as primers. sequences of 228-231 base pairs (bp) were amplified by pcr from 25 taiwan isolates and 4 reference strains (h120, conn, ... | 1996 | 8893790 |
| isolation, pathogenicity, and h120 protection efficacy of infectious bronchitis viruses isolated in taiwan. | seven isolates of infectious bronchitis (ib) virus (ibv) were isolated from two breeder farms and five broiler farms in taiwan in 1992. the cardinal signs of disease in breeders were egg production drops and watery albumen, and those in broilers were respiratory distress and renal urate deposition or death. all diseased chickens had been vaccinated with ib vaccines (mostly h120). the viruses were isolated and identified by chicken embryo inoculation and electron microscopy. the genomes of the is ... | 1996 | 8883793 |
| the genotyping of infectious bronchitis virus in taiwan by a multiplex amplification refractory mutation system reverse transcription polymerase chain reaction. | infectious bronchitis virus (ibv; avian coronavirus) causes acute respiratory and reproductive and urogenital diseases in chickens. following sequence alignment of ibv strains, a combination of selective primer sets was designed to individually amplify the ibv wild-type and vaccine strains using a multiplex amplification refractory mutation system reverse transcription polymerase chain reaction (arms rt-pcr) approach. this system was shown to discriminate the ibv wild-type and vaccine strains. m ... | 2014 | 25223342 |
| evolution of infectious bronchitis virus in taiwan: characterisation of rna recombination in the nucleocapsid gene. | avian infectious bronchitis virus (ibv) belongs to the coronaviridae family and causes significant economic loss in taiwan (tw), even in flocks that have been extensively immunised with massachusetts (mass)-serotype vaccines. phylogenetic analysis of all non-structural and most structural genes shows that tw ibv is genetically distinct from the us strain and more similar to chinese (ch) ibv. in contrast, the nucleocapsid (n) gene of tw ibv presents phylogenetic incongruence. rna recombination at ... | 2010 | 20299165 |
| development of attenuated vaccines from taiwanese infectious bronchitis virus strains. | due to variations in serotypes among different strains of avian infectious bronchitis viruses (ibv), vaccination of chicks with imported vaccines fails to protect them from ibv infections in taiwan. therefore, we develop attenuated vaccines from local strains in taiwan. a taiwan group i (tw i) strain was passaged 74 times through specific pathogen-free (spf) chicken embryonated eggs, and then tested in spf chickens. the attenuated vaccine was not pathogenic in 1-week-old chicks, had a neutraliza ... | 2006 | 16239054 |
| emergence of novel nephropathogenic infectious bronchitis viruses currently circulating in chinese chicken flocks. | the emergence of novel infectious bronchitis viruses (ibvs) has been reported worldwide. between 2011 and 2014, eight ibv isolates were identified from disease outbreaks in northeast china. in the current study we analysed the s1 gene of these eight ibv isolates in addition to the complete genome of five of them. we confirmed that these isolates emerged through the recombination of lx4 and taiwan group 1 (tw1) viruses at two switch sites, one was in the nsp 16 region and the other in the spike p ... | 2016 | 26551660 |
| detection of infectious bronchitis virus strains similar to japan in taiwan. | a total of 1,320 tracheal samples from 66 broiler flocks sent to slaughterhouses and 42 tracheal samples from 42 flocks of local chickens in the field were collected for infectious bronchitis virus (ibv) gene detection by reverse transcription polymerase chain reaction using nucleocapsid-specific primers and spike-specific primers. prevalence in broiler flocks was 39.4% (26/66) and in local chicken flocks was 11.9% (5/42). several ibvs similar to japan were detected in taiwan. one-direction neut ... | 2016 | 26822119 |