The effect of crude protein (CP), amino acid (AA), and dietary electrolyte balance (DEB) were evaluated on blood parameters, carcass traits, and broiler performance under heat stress (29-34°C). A total of 540 male chickens (Ross 308) were allocated to 12 diets with factorial arrangement 2 × 2 × 3, using a completely randomized design with three replicates of 15 chickens in grower (13 to 26 days) and finisher (27 to 42 days) periods. and 120, 220, and 320 mEq kg-1 DEB. The level of 21% CP increased body weight gain (BWG) and decreased feed conversion ratio (FCR) at grower period (p < 0.05). In contrast, 20% CP level decreased BWG and increased FCR at finisher period (p < 0.05). Further, 20% CP level reduced blood sodium and blood electrolyte balance (p < 0.05). The highest blood electrolyte balance was achieved by DEB 320 mEq kg-1 diet (p < 0.05). Broiler response to DEB in heat stress depended on the age of bird, length of exposure to high temperature and CP level of the diet. Under heat stress (29-34°C), the 21% CP level at grower period and 17% CP level at finisher period improved broiler BWG and FCR.
