UTILIZATION OF U-C-14-LYSINE BY YOUNG TURKEYS

1. U-C-14-lysine was administered by tube into the crop to turkey poul ts fed on assay diets (maize + sesame + maize gluten meal) containing varying concentrations of lysine, and partition of the label into body components, carbon dioxide, and excreta was measured. 2. Deposition o f C-14 label into breast and heart muscles responded positively to die tary lysine concentration. There was no apparent relationship between dietary lysine intake and deposition of label into carbon dioxide or e xcreta. 3. Efficiency of lysine retention? above maintenance, was esti mated to be 0.523 +/- 0.034. 4. Turkeys exhibited variable metabolic e fficiency in the use of lysine as indicated by loss of U-C-14-lysine l abel to expired carbon dioxide and to excreta by individual turkeys.