Abstract
The relationship between dietary protein, essential amino acids (EM) and energy was examined in two experiments using male broiler chicks fed practical diets to eight weeks of age. All diets contained a balanced proportion of ten EAA which was maintained over various treatments. Growth of birds was closely related to the EAA content of the diet and poorly related to dietary protein content. When the dietary concentration of ten EAA was treated as a combined unit and expressed as proportion of diet, 7.6 per cent EAA in an 18 per cent protein starter diet and 5.8 per cent EAA in a 16 per cent protein finisher diet were adequate to support maximal growth of male birds to eight weeks of age. Feed intakes were reduced as energy concentrations increased in diets regardless of protein content of diets.