Molecular characterisation of infectious bursal disease virus (IBDV) isolated from commercial broiler chickens in Nile Delta

Abstract

Infectious bursal disease virus (IBDV) is a highly infectious disease affecting young chickens that alters predominantly the immune system. Emergence of new variants causes severe economic losses not only in Egypt but also all over the world. For this purpose assessment of infectious bursal disease virus (IBDV) genotypes in 20 commercial broiler flocks aged 20–35 days raised in 5 provinces in the Nile Delta, Egypt (Gharbia, Dakahlya, Kafr El sheikh, Zagazig and Domietta) was carried out. All flocks were vaccinated against IBD virus. RT-PCR revealed successful amplification of 620 bp of VP2 in 17 out of 20 samples (85%). VP2 gene nucleotide sequence analysis of six IBDV isolates (F342-1, F342-2, F342-4, F342-5 and F342-7) revealed 99.1 % similarity to the Giza 2000, Giza 2008 vv, SV-G1, SV-G2, SV-G4 and SV-G5 which were very virulent IBDV strains while the isolate F342-3 was close to D78 classical vaccinal strain and Kal 2001 classical IBDV strain variant.

Comparative Evaluation of HVT-IBD Vector, Immune Complex, and Live IBD Vaccines against vvIBDV in Commercial Broiler Chickens with High Maternally Derived Antibodies

“…However, IBDV is evolving quickly in the field [8], resulting in the emergence of antigenic variants of IBDV in the early 1980s [9] and very virulent IBDV (vvIBDV) strains in the late 1980s [10]. Egypt is not far from what occurs, as variant strains of IBDV was recorded [11,12], but the most prevalent IBDV strain in the field is vvIBDV [12,13,14,15] and thus, the situation with IBDV is becoming more complex [16] and the development of the IBD virus’s antigenicity and virulence has made the control of IBDV by vaccination more challenging [17].…”