The growth to maturity of lean and fat lines of broiler chickens fed diets of different protein content: Evaluation of a model to describe growth and feeding characteristics

Abstract

ABSTRACTBody weight and food intake were measured at different ages up to 30 weeks in males and 21 weeks in females in lean, fat and commercial lines of broiler chickens given diets of different crude protein content. The lean and fat lines showed no differences in rates of body-weight gain or final body weights but the lean line had consistently lower food intakes. Dietary protein concentration within the ranges studied did not influence final body weights.Equations derived from a theory of feeding and growth were used along with the data up to 21 weeks of age to calculate mature body weights and various feeding characteristics. These values were compared with those obtained by application of the theory to another set of broiler data. The theory was found to be sufficiently robust to give some consistent interpretations of data from experiments involving considerable differences in time, breed and diet.