Research Note: Comparison of Restricted and Increasing Light Programs for Male Broiler Performance and Carcass Yield

Abstract

The purpose of this study was to compare the effectiveness of restricted or increasing light with conventional near continuous light for improving performance of male broilers. Fifty day-old male broiler chicks (Cobb × Arbor Acres) were placed in each of 16 light-controlled chambers. Four chambers were randomly assigned to each of four light treatments: 1) 23 h light (L):l h dark (D) (23L); 2) 16L:8D (16L); 3) 14L:10D (14L); or 4) 23L:1D from Days 1 to 3, 6L:18D from Days 4 to 13, 10L:14D from Days 14 to 20, 14L:10D from Days 21 to 27, 18L:6D from Days 28 to 34, and 23L:1D from 35 to 49 days of age (INC). Ten birds per chamber were randomly selected for processing at 49 days of age. Treatments 16L, 14L, and INC had lower mortality than Treatment 23L (3.0, 3.5, and 3.5 versus 9%, respectively). There was a significant overall treatment effect for BW with Treatment 23L having greatest BW from 7 to 42 days; however, BW was not significantly (P ≥ .05) different at 48 days (2,924, 2,912, 2,850, and 2,884 g for Treatments 23L, 16L, 14L, and INC, respectively). Tender yield (per lean carcass weight) was greater in Treatment 23L than in Treatment 14L (4.64 versus 4.42%, respectively), and a converse relationship existed for drumstick yield (14.44 versus 15.07%, respectively). Fillet yield was greater in Treatment 23L than in Treatments 16L, 14L, and INC (20.06 versus 18.86, 18.94, and 19.04%, respectively). Restricted light programs (14L and 16L) were as efficacious as increasing light (INC) for improving broiler livability but had a similar negative influence on breast meat yield.