<b>The effects of protein, amino acid, and dietary electrolyte balance on broiler chicken performance and blood parameters under heat stress

Abstract

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.