Effects of a two-phase mixed color lighting program using light-emitting diode lights on layer chickens during brooding and rearing periods

The behavior, growth and development, and production performance of poultry are affected by the light environment. The influence of light results from a combination of light sources, light intensity, light color, and the photoperiod regimen. With light-emitting diode (LED) lamps applied in poultry housing systems, specific light colors are desired for each time period for layer chickens. The objective of this study was to investigate the effects of a 2-phase mixed color lighting program (phase 1: blue-green, 1 D–13 wk; phase 2: yellow-orange, 14–20 wk) using LED lights on the blood parameters, skeletal development parameters, and sexual development parameters of caged layer chickens during their brooding and rearing periods. Fifty-two chickens were raised from 1 D to 20 wk of age in each of the 4 treatment groups with 3 replicates, with white (400–700 nm) light at phase 1 and phase 2 (WL treatment as the control); blue–green (435–565 nm) light at phase 1 followed by yellow–orange (565–630 nm) light at phase 2 (BG-YOL treatment); yellow–orange LED (565–630 nm) light at phase 1 and phase 2 (YOL treatment); and blue–green (435–565 nm) light at phase 1 and phase 2 (BGL treatment). The results showed that the serum Ig concentrations of the layer chickens in the BG-YOL treatment and BGL treatment were higher than those in the WL treatment at 13 wk of age (P