caa a22 4500 397567685 CHVBK 20180308164832.0 cr unu---uuuuu 161202e199611 xx s 000 0 eng 10.3382/ps.0751345 doi (NATIONALLICENCE)oxford-10.3382/ps.0751345 Lighting Programs for Broilers That Reduce Leg Problems Without Loss of Performance or Yield [Elektronische Daten] [J. A. RENDEN, E. T. MORAN, S. A. KINCAID] This study tested the effects of light schedules on performance and yields of broiler chickens. In Experiment 1, light treatments during Days 1 to 49 of age were: 1) 23 h light (L):1h dark (D); 2) 16L:8D; 3) 16L: 3D:1L:4D; and 4) 16L:2D:1L:2D:1L:2D. In Experiment 2, Light Treatments 1 and 2 were the same as Treatments 1 and 4, respectively, in Experiment 1; 3) 23L:1D Days 1 to 7,16L:8D Days 8 to 14, the light period was increased by 2 h/wk during Days 15 to 35, and 23L:1D Days 36 to 42; and 4) 23L:1D Days 1 to 7, 16L:8D Days 8 to 14, 16L:3D: 2L:3D Days 15 to 21, 16L:2D:4L:2D Days 22 to 28, 16L:1D:6L:1D Days 29 to 35, and 23L:1D thereafter. In Experiment 1, BW was greater in Treatment 4 than Treatment 2 at 22 (708 vs 642 g) and 49 d (2,948 vs 2,797 g), percentage leg problems was lower in Treatments 2 to 4 (9, 10, and 6%, respectively) than in Treatment 1 (20%), and percentage Grade A was greater in Treatment 4 than Treatment 2 (60 vs 46%) at 49 d. In Experiment 2, BW was greater in Treatment 1 (692 g) than Treatments 3 (617 g) and 4 (620 g) at 21 d, and the incidence of tibial dyschondroplasia was lower in Treatment 2 (3.1%) than Treatment 3 (15.3%) at 42 d. There were no differences for mortality among treatments in either experiment. © 1996 Poultry Science Association, Inc. Education and Production nationallicence light nationallicence broiler nationallicence body weight nationallicence leg problems nationallicence carcass yield nationallicence RENDEN J. A. Department of Poultry Science, Alabama Agricultural Experiment Station, and aut MORAN E. T. Department of Poultry Science, Alabama Agricultural Experiment Station, and aut KINCAID S. A. Department of Anatomy and Histology, Auburn University, Alabama 36849 aut Poultry Science Oxford University Press 75/11(1996-11), 1345-1350 0032-5791 75:11<1345 1996 75 ps https://doi.org/10.3382/ps.0751345 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.3382/ps.0751345 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- RENDEN J. A. Department of Poultry Science, Alabama Agricultural Experiment Station, and aut NATIONALLICENCE 700 1- MORAN E. T. Department of Poultry Science, Alabama Agricultural Experiment Station, and aut NATIONALLICENCE 700 1- KINCAID S. A. Department of Anatomy and Histology, Auburn University, Alabama 36849 aut NATIONALLICENCE 773 0- Poultry Science Oxford University Press 75/11(1996-11), 1345-1350 0032-5791 75:11<1345 1996 75 ps Metadata rights reserved CC BY-NC-4.0 http://creativecommons.org/licenses/by-nc/4.0 nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-oxford