The Behavioral Preferences and Performance of Female Broilers under Unevenly Distributed Yellow LED Lights with Various Intensities

Abstract

<abstract> <bold><sc>Abstract.</sc></bold> Light-emitting diode (LED) light sources show a high potential for replacing traditional incandescent lamps in broiler production facilities. LEDs offer clear advantages in energy efficiency. However, the application of LED technology to broiler production is restricted because of the absence of research about its uneven distribution of light intensity and subsequent impacts on broilers. This study investigated the effect of unevenly distributed yellow LED lights with different light intensities on the behavioral preferences and performance characteristics of female broilers. Four pens were developed to provide two unevenly distributed lighting environments with maximum light intensities (MLIs) of 90 and 60 lx in a study including replicates. Each pen consisted of four subzones characterized by their light intensity, including three subzones of high intensity (HI), medium intensity (MI), and low intensity (LI) in the lighting area (LA) and one non-lighting area (NA). Thirty female broilers were reared in each pen and were free to eat, drink, and stay in any subzone. No significant difference between the 90 and 60 lx experimental groups was found in feed conversion ratio (FCR), body weight (BW), uniformity, or growth ratio. The birds in both groups tended to drink water (p < 0.05) in the LI and MI subzones during the first three weeks. The preference of the birds then shifted to the MI and HI subzones with the growth of the birds despite substantial fluctuations within replicates. In both groups, feed intake was less affected than water intake by the uneven distribution of light intensity. The birds showed a transient feeding preference for LI and HI at young and old ages, respectively. The video data demonstrated that the birds showed a diurnal preference for LI (<2 lx) and a nocturnal preference for MI. The daily overall results showed higher preferences for NA in both groups. The preference-based lighting regimes indicated that the birds need less lighting time during the daytime than the nighttime. This study can provide further knowledge about broilers’ performance and behavior patterns in LED lighting environments, thus providing reference information for the configuration of LED arrays in commercial poultry production.