Broiler Genetics May Influence Performance Response When Fed Low Crude Protein Diets

Abstract

Background and Objective: Genetic selection for rapid growth and increased meat yield in a short period of time has greatly improved feed efficiency. However, the increased pressure for growth has prompted unforeseen consequences of other stressors on the broiler bird. These stressors utilize energy and nutrients that otherwise would be utilized for growth. This study was designed to evaluate how two genetic lines would perform while consuming less protein as a potential model to evaluate feed additives that may improve digestibility or immune and oxidative status. Materials and Methods: A field study was conducted and a reduced protein model was used in these two experiments. In experiment 1, Cobb 500 male broiler chicks were randomly allocated to one of two dietary treatments: Nutrient adequate basal diet and the basal diet with reduced crude protein. In experiment 2, Cobb 700 male broiler chicks were randomly assigned to the experimental diets used in experiment 1. Results: Body weight was decreased in Cobb 500 broilers compared with Cobb 700 broilers when dietary crude protein was reduced. Furthermore, Cobb 500 broilers consumed less feed compared with Cobb 700 broilers when dietary crude protein was reduced. Conclusion: As a producer, it is essential to find the point of maximum economic efficiency for the strain of broilers being reared. These data indicated differences among broiler genetic lines and dietary crude protein need to be considered when formulating diets.