Seven-week-old commercial egg-type chickens were infected with a local isolate of infectious bursal disease virus ( vvVIBDV ) . Sacrificed and dead birds were examined at 1,2,3,4,5,6 and7days post-infection (PI).The results revealed severe clinical signs 2 days P " Course of the disease was short with highine a mortality . Sixty eight percentage bl vi a. birds were died , 67% of them en days PI with distinct pathological ta hades, bursa of Fabricius (BF), thymus Ca Nmphoia ees (GH) . These included fo-Iho liste and depletion in bursal » Cortical lymphoid necrosis iMus and plasma cell depletion in GH.