الفهرس | Only 14 pages are availabe for public view |
Abstract Infectious bursal disease virus remerged frequently in Egypt, causing serious economic losses. The disease is acute contagious disease in young chickens from 3-6 weeks of age. In present study forty field bursa samples were collected from different Egyptian governorates, detection of IBDV in the collected samples were done using RT-PCR. Eight samples showed positive results by percent of (20%). Sequence analysis and characterization of the hyper variable region of VP2 gene from four strains purified from the PCR product showed many amino acid substitutions that may affect IBDV antigenicity and virulence. Comparative phylogenetic analysis based on the sequence of the hypervariable region of VP2 gene show that the strains were closer to Giza 2008 strains. This study reports the continuous circulation of vvIBDV strains in vaccinated flocks 4 governorates 2Giza, Sharkia, Behira and Dakahlia3, in Egypt during year 2015. There are need to review the control and vaccination strategy of IBDV in broiler flocks specially the extensive abuse of using classical vaccines |