Isolation, molecular characterization and pathogenicity of IBDV associated with mortalities in broiler chickens / Reem Ahmed Said Ahmed Soliman ; Supervised Hussein Aly Hussein Ahmed , Ismaiel Mohamed Reda , Mounir Mohamed Elsafty

Thesis (Ph.D.) - Cairo University - Faculty of Veterinary Medicine - Department of Virology

The present study was performed to detect, isolate and identify the causative agent associated with mortalities in broiler flocks in Beheira Governorate in EGYPT. Field samples were collected from broiler chickens demonstrating mortalities. The samples were inoculated in one-day old SPF chicks via intranasal and intraocular route. Chicks were kept in isolators with daily observation for five weeks post infection. Blood samples were collected and tested for infectious bursal disease virus (IBDV), chicken anemia virus (CAV), infectious bronchitis virus (IBV), Newcastle disease virus (NDV) and Avian influenza H5 and H9 subtypes by ELISA and HI tests. The results indicated that the samples were positive for IBDV. Histopathological examination of the collected bursae and kidneys, four and seven days post inoculation (DPI) revealed characteristic lesions for IBDV including inter-follicular connective tissue proliferation, compressed follicles, depleted lymphocytes in the bursae, congested blood vessels and hemorrhage in the kidneys. Conventional Reverse transcriptase-polymerase chain reaction (RT-PCR) and Real-time RT-PCR (rtRT-PCR) assays for VP2 gene of IBDV confirmed the presence of IBDV. Sequence analysis of amplified PCR product indicated continuous circulation of virulent IBDV strains in Egypt and it was closely related to previously isolated very virulent strain Giza 2008. Respective nucleotide sequence was submitted to NCBI GenBank with the access number KY200662

Issued also as CD