The influence of sodium bicarbonate and sulfur amino acids on the performance of broilers at moderate and high temperaures

Abstract

Supplements of sodium bicarbonate (NaHCO3) added to the diet or drinking water of finishing broilers (3-6 weeks of age) improved food intake, live weight gain and food efficiency at high (30¦C), but not at moderate (2l¦C), temperatures. The improved performance was not related to increases in amino acid digestibilities which were reduced in birds kept at 30¦C. Increased consumption of drinking water appears to be a major prerequisite for the improved performance at high temperatures. The methionine : total sulfur amino acid (TSAA) ratio of the diets also influenced broiler performance at 30¦C with ratios of 0.43 and 0.55 giving superior growth and food conversion to a ratio of 0.62. The intake of drinking water and the water : food intake ratio were significantly reduced at the dietary methionine : TSAA ratio of 0.62, the effect being significant when the drinking water contained NaHCO3.