Behavior of broilers subjected to different light spectra and illuminances

Abstract

ABSTRACT The ideal illuminance in poultry houses for broiler chickens may lead to improvement in housing efficiency and broiler welfare. In this context, the objective of this research was to evaluate the behavior and welfare of broiler chickens under effect of illuminance by light-emitting diode (LED) in white band (400-760 nm) and blue/green band (470-525 nm). The experiment was conducted from October to December 2017, in the municipality of Carpina, PE, Brazil, and had 384-oneday-old chicks (mixed batch), Cobb 500 strain. The adopted design was completely randomized, in a 4 x 2 factorial scheme, corresponding to four illuminances, 5 lx (I1), 20 lx (I2), 150 lx (I3) and 5-20 lx (5 lx in the 1st, 2nd and 6th weeks and 20 lx in the 3rd, 4th and 5th weeks - I4), and two light spectra using LED bars, RGB type, in white (400-760 nm) color (C1) and blue/green (470-525 nm) dichromatic color (C2), with three repetitions. A continuous lighting program was used, 18 h of light and 6 h of dark per day. Ingestive, posture, comfort and natural behaviors, aggressiveness and discomfort of the broiler were evaluated. Broiler behavioral variables were determined by the frequency of the events and their probability of occurrence by the Chi-square test. Broilers subjected to wavelengths in the blue/green range and illuminance of 20 lx and 5-20 lx showed more significant ingestive and comfort behaviors, which demonstrates better welfare under these housing conditions.