Molecular Characterization and Demographic Study on Infectious Bursal Disease Virus in Faisalabad District

Abstract

The re-emergence of virulent strains of the Infectious Bursal Disease Virus (IBDV) leads to significant economic losses of poultry industry in Pakistan during last few years. This disease causes the infection of bursa, which leads to major immune losses. A total number of 30 samples from five IBD outbreaks during the period of 2019–20 were collected from different areas of Faisalabad district, Pakistan and assayed by targeting the IBD virus VP2 region through RT-PCR. Among all the outbreaks, almost 80% of poultry birds were found positive for the IBDV. The bursa tissues were collected from the infected birds and histopathological examination of samples revealed severe lymphocytic depletion, infiltration of inflammatory cells, and necrosis of the bursa of Fabricius (BF). Positive samples were subjected to re-isolation and molecular characterization of IBDV. The Pakistan IBDV genes were subjected to DNA sequencing to determine the virus nucleotide sequences. The sequences of 100 Serotype-I IBDVs showing nearest homology were compared and identified with the study sequence. The construction of the phylogenetic tree for nucleotide sequences was accomplished by the neighbor-joining method in MEGA-6 with reference strains. The VP2 segment reassortment of IBDVs carrying segment A were identified as one important type of circulating strains in Pakistan. The findings indicated the molecular features of the Pakistan IBDV strains playing a role in the evolution of new strains of the virus, which will contribute to the vaccine selection and effective prevention of the disease.

IgY: A Key Isotype and Promising Antibody for the Immunoprophylaxis Therapy of Infectious Bursal Disease Virus Infections

“…The sonicated antigen was centrifuged at 5000 rpm for 15 min and the supernatant was collected. The IBD virus was characterized in the previous study by [5].…”

Detection and Phylogenetic Analysis of Infectious Bursal Disease Virus Based on both Genome Segments A and B Isolated from Backyard Poultry Punjab, Pakistan

“…In 1980 a vvIBDV outbreak was first recorded with high mortality in Punjab Pakistan (Khan et al, 1988) and since then continues to pose a threat by various strains all over the country (Lone et al, 2009;Zahoor et al, 2011). Despite extensive vaccination programs, IBD still prevails at the poultry farms posing significant economic losses in Pakistan, which emphasizes the characterization of field circulating IBDV strains to understand the causes of vaccination failure, hence incorporating local viruses in vaccine development (Shafqat et al, 2017;Sajid et al, 2021). Traditionally, nucleotide sequencing of the segment A coded VP2 hypervariable region is used for genotypic characterization of IBDV strains.…”