Experimental study was carried out t0 compre protection induced by two infections bursal disease (IBD) vaccination programs is Commercial broilers. chicken inoculated with live vaccine at 7 and s21v days old were protected against mortality but clinical signs of IBD were noted after challenge at 28 and 35 days old. 
Chickens inoculated with both live vaccine (at 7 & 21 days old) and inactivated vaccine (at 8 days old) were better protected against challenge at 28 and 35 days of age. This vaccination program protected  challenged chickens against both mortality and clinical IBD signs. However, the bursa: body Weight ratios were lower than those of the control 
birds (P<0.05).