The study aimed to evaluate the immune response of broilers vaccinated with the Vaxxitek® HVT+IBD+ND vaccine following treatment with Ceftiofur. A total of 250 broiler chickens were divided into control group without treatment or vaccination, ceftiofur treated group, vaccinated group that received Vaxxitek® vaccination without Ceftiofur treatment then challenged with IBDV at 24 days, Vaccinated and Treated Group that vaccinated with Vaxxitek® and treated with Ceftiofur, then challenged with IBDV at 24 days and conventional vaccine group that received conventional live IBD vaccines at 10 and 18 days, along with Ceftiofur treatment. The group receiving both Vaxxitek® and Ceftiofur showed no adverse effects on RBCs and hemoglobin levels, while demonstrating significant improvements in lymphocyte and monocyte counts compared to other groups also, minimal lymphoid atrophy and well-preserved bursal structure in this group. In contrast, the control group exhibited a significant decrease in lymphocyte counts when treated with Ceftiofur. Overall, the findings concluded that Vaxxitek® vaccination combined with Ceftiofur treatment leads to a better immune response in broilers, providing effective protection against IBDV and Newcastle disease while preserving bursal structure and function.