decreasing weights of lymphoid organs, total circulating antibodies, and phagocytic ability of macrophages (Quinteiro-Filho et al., 2012). Basically, birds attempt to maintain their thermal homeostasis from heat stress. During this process, the level of reactive oxygen species (ROS) is increased, the body enters a stage of oxidative stress, and heat shock proteins are released in response to stress, providing protection from ROS effects (Droge, 2002).