Amino Acid Requirements for Maintenance in the Adult Rooster

Abstract

The maintenance requirements for L-glutamic acid, L-histidine, L-lysine and L-arginine have been determined for the adult rooster not previously depleted of his protein reserves using a free amino acid diet. Using a 5-day feeding period nitrogen balance was employed as a criterion of adequacy. Since the same amount of diet, differing only in quantity of test amino acid (with compensatory nitrogen), was fed, the requirement for an amino acid was taken as that level of an amino acid which would maintain the same level of nitrogen excretion as observed on the complete starting amino acid diet. The minimal maintenance level was taken as the lowest level of an amino acid which would maintain the animal in nitrogen balance. L-Glutamic acid and L-histidine were found to be non-essential as judged by either criterion. The requirement for L-lysine was found not to exceed 29 mg/kg/day and no minimal maintenance level could be demonstrated. The requirement for L-arginine was observed to be 120 mg/kg/day with a minimal maintenance level of 54 mg/kg/day. The relationship of the amino acid requirements for feather synthesis to the maintenance requirement of the rooster have been discussed.