Dietary sodium and chloride for twenty-nine- to forty-two-day-old broiler chickens at constant electrolyte balance under subtropical summer conditions

The study was conducted to evaluate the response of broiler chicks to different dietary Na+ and Cl-concentrations with similar dietary electrolyte balance of 250 mEq/kg during 29 to 42 d of age in a hot environment with average minimum and maximum temperatures of 32.4 and 36.6 degrees C, respectively, and an average RH of 69.2%. Three levels of dietary Na+ (0.20, 0.25, and 0.30%) and 3 levels of dietary Cl-(0.30, 0.40, and 0.50%) were used in 3 x 3 factorial arrangement in which BW at 28 d were used as covariate in the statistical analysis. A decreasing linear effect of dietary Na+ was observed on breast yield and lowering of abdominal fat, whereas increasing dietary Cl-linearly increased litter moisture and decreased dressing weights. No significant effects of dietary Na+, Cl-, or Na+ x Cl-were observed on feed intake, BW gain, feed: gain, rectal temperature, water: feed, or mortality. An improvement in litter condition, toe ash, blood parameters, and lowered abdominal fat yield was observed for the diet having 0.30% dietary Na+. The results of the present study suggest the dietary requirements of 0.20 to 0.25% Na+ and 0.30% Cl-during the finisher phase (29 to 42 d) of broiler chicks when the ambient temperature ranged from 32 to 40 C.