Effect of vaccination program on immune response, production performance, and carcass composition of Ross 308 broiler chickens.

The aim of this study was to compare the effect of 2 different vaccination programs using vaccines against infection bronchitis virus (IBV) and avian metapneumovirus (aMPV) on the humoral immune response, production performance, carcass weight and composition, and the percentage of selected internal organs. During the rearing of broiler chickens, blood was collected for serum samples from randomly selected birds from each experimental group on d 1, 21, 28, and 38. Geometric mean titer (GMT) values were determined for the aforementioned diseases using serological ELISA tests, performed during routine veterinary inspections.