comparison of serum antibody titer of 8 types of commercial live infectious bronchitis vaccine in broiler chickens

The aim of this study was to compare the serum antibody titer of 8 types of commercial live infectious bronchitis vaccines in broiler chickens. Three hundred and twenty one-day-old male broiler chickens (308 Ross strain) were divided into 8 groups (each group comprised of 3 replicates) randomly. At 8 days of age, each treatment group received different types of live infectious bronchitis vaccine by eye-drop method. Twelve birds from each group were randomly chosen and blood sample was taken on the 22nd and 29th days of experimental period and ELISA test was performed on sera for detection of sample antibody titer. The mean of serum antibody titer against infectious bronchitis vaccines among treatment groups on the 22nd day of experimental period showed statistical significance between the group that had received HIPRAVIAR Colon/ H120 and the groups that had received Nobilis Ma5+ Clone30, H120 and Cevac Vitabron L (p