Accretion Rates and Efficiency of Amino Acid Utilization during the Twenty-nine Days Post-Hatch Period in Male Ducks

The amino acid contents of whole body were determined in male ducks at 5 age intervals from d 1 to 29 post hatch. Whole body homogenates were analyzed of dry matter, nitrogen, and amino acids and used to determine amino acid accretion rates and efficiency of utilization of digestible amino acids for amino acid accretion. During periods d 1 to 8, d 8 to 15, d 15 to 22, and d 22 to 29 post hatch, growth rates of the duck averaged 29, 61, 79, and 92 g/d, respectively. There were rapid increases in rates of amino acid accretion during the periods of d 1 to 8, d 8 to 15, and d 15 to 22 and a leveling off during d 22 to 29 period of growth as shown by the linear (P