Abstract
1. The leucine, isoleucine and valine requirements of the 3‐week‐old turkey were determined in a factorial experiment and were found to be 1.42, 0.84 and 1.21% respectively in semi‐purified diets containing 12.5 MJ ME/kg. 2. It is suggested that the efficiency with which turkeys and chicks utilise isoleucine and valine is similar, and that a daily intake of about 325 mg of valine would sustain a rate of growth of about 23 g/d in both species.