In commercial broiler flocks, the rates of maternal antibodies were detected between 98 -100 % , 5 -60 %, and 0 -15 % in flocks with a day and a week old, with two weeks old, and with three weeks old, respectively. The anti-CAV antibody existence were detected at the rate of 62.5 and 93.8 % in 8 commercial broiler flocks with four weeks old and 16 commercial broiler flocks with five weeks old of vaccinated broiler breeder flocks, respectively. CAV VP1 and VP2 genes were detected in 25 % of three weeks old, 37.5 % four weeks old flocks of 8 commercial broilers and in 37.5 % of five weeks old flocks of 16 commercial broilers of vaccinated broiler breeder flocks. However, no CAV antibody, CAV VP1 and VP2 genes were detected in 8 commercial broiler flocks of non-vaccinated broiler breeder flocks.