The Avian Infectious Bronchitis Virus (AIBV) from Broiler/Layer Chickens Demonstrates Evidence of Recombination with SomeField and Vaccine Strains of the AIBV
Faculty Mentor
Maged Gomaa Hemida
Area of Research
Virology, Genetics
Major
Veterinary Medicine
Description
The major goal of this study was to monitor genetic changes in the viral genomes of some recent field isolates of the AIBV from broiler chickens. To achieve these goals, we tested several pools of tissue specimens (trachea and kidneys) from some suspected AIBV outbreaks in broiler chickens by quantitative real-time PCR (q-RT-PCR). We selected two samples, one from the trachea (IBV-4) and one from the kidney (AIBV-6), that showed the lowest Ct values in the q-RT-PCR for the next-generation sequencing (NGS). The full-length genomes of these two isolates were deposited in the GenBank (Accession Numbers: PQ468962 and PQ468963). The viral genome size of AIBV-4 and AIBV-6 was 27,475 and 27,469 nucleotides in length. IBV-4 has typical IBV genome organization (5’UTR, ORF1a, ORF1b, S, 3a, 3b, E, M, 4b, 5a, 5b, N, and 3’UTR), while IBV-6 lacks 5b. These two IBV isolates belong to genotype GI-1 based on the phylogenetic using the full-length, the S, and the N protein sequences. The S1/S2 cleavage sites show polybasic amino acid sequences (RR-F-RR) as direct evidence of the virulence of these isolates in chickens. The recombination analysis shows multiple recombination events of these isolates with some natural and vaccine strains. The potential major parent for both IBV-4 and IBV-6 was IBV Beaudette, and the potential minor parent was the AIBV Arkansas DPI. Vigilant monitoring of the AIBV sequences of the currently circulating strains in chickens is highly encouraged to develop novel vaccines and diagnostic assays that match the field-circulating strains. Keywords: AIBV, genome sequences, NGS, recombination, respiratory, nephropathogenic
The Avian Infectious Bronchitis Virus (AIBV) from Broiler/Layer Chickens Demonstrates Evidence of Recombination with SomeField and Vaccine Strains of the AIBV
The major goal of this study was to monitor genetic changes in the viral genomes of some recent field isolates of the AIBV from broiler chickens. To achieve these goals, we tested several pools of tissue specimens (trachea and kidneys) from some suspected AIBV outbreaks in broiler chickens by quantitative real-time PCR (q-RT-PCR). We selected two samples, one from the trachea (IBV-4) and one from the kidney (AIBV-6), that showed the lowest Ct values in the q-RT-PCR for the next-generation sequencing (NGS). The full-length genomes of these two isolates were deposited in the GenBank (Accession Numbers: PQ468962 and PQ468963). The viral genome size of AIBV-4 and AIBV-6 was 27,475 and 27,469 nucleotides in length. IBV-4 has typical IBV genome organization (5’UTR, ORF1a, ORF1b, S, 3a, 3b, E, M, 4b, 5a, 5b, N, and 3’UTR), while IBV-6 lacks 5b. These two IBV isolates belong to genotype GI-1 based on the phylogenetic using the full-length, the S, and the N protein sequences. The S1/S2 cleavage sites show polybasic amino acid sequences (RR-F-RR) as direct evidence of the virulence of these isolates in chickens. The recombination analysis shows multiple recombination events of these isolates with some natural and vaccine strains. The potential major parent for both IBV-4 and IBV-6 was IBV Beaudette, and the potential minor parent was the AIBV Arkansas DPI. Vigilant monitoring of the AIBV sequences of the currently circulating strains in chickens is highly encouraged to develop novel vaccines and diagnostic assays that match the field-circulating strains. Keywords: AIBV, genome sequences, NGS, recombination, respiratory, nephropathogenic