Selecting for efficiency of egg production using food‐consumption records in layer‐type chickens

Abstract 1. The purpose of the experiment was to evaluate the use of food consumption records in selection to improve layer‐type chickens. 2. Twelve subpopulations of Leghorns, including 5878 tested birds, were used in a selection experiment which lasted 5 generations. Four were selected using an index (I1) that combined information on body weight (BW), egg‐mass output (EM), and individual food‐consumption records (FC). Four were selected using an index (I2) that combined information just on BW and EM. The remaining 4 served as controls, with selection differentials set to zero in each generation. 3. Differences between the selected groups, control‐corrected each generation, measured the “food‐record effect”. 4. Including food‐consumption records in the selection criterion resulted in increased body weight (7%), reduction in food consumption (6 to 9%), increase in food efficiency (egg mass/food consumption) (2 to 5%), and increase in income over food costs (10%), relative to selection not involving food r...