Feeding Behaviors of Broilers at Chicken-perceived vs. Human-perceived Light Intensities under Two Light Spectrums

摘要

Broilers perceive light intensity differently from human due to differences in spectral sensitivity. Better understanding of broiler behavioral responses to their perceived lighting may inform farm management practices which helps to improve animal welfare and productivity. The objective of this study was to investigate broiler feeding behaviors at chicken- vs. human-perceived light intensities and under broiler specific LED (BLED) vs. conventional LED light spectrums. The treatment combinations of light intensities and light spectrums were randomly assigned to four identical experimental rooms (3.8 xi.5 m, L*W), each with 60 tagged broilers. Light intensities at bird level were maintained at either 5 clux (chicken-perceived light intensity) or 5 lux (human-perceived light intensity). Ultra-high frequency radio frequency identification (UHF-RFID) systems were used to register broilers at the feeders. Feeding behaviors of individual broilers at each treatment combination were summarized in terms ofdaily time spent (DTS) at a feeder, daily percentage of time spent (DPTS), daily times of visit (DTV) to a feeder, duration per visit (DV), hourly time spent (HTS) at a feeder, and hourly times of visit (HTV) to a feeder. The results showed that the DTS(mean ± standard deviation SD', h-bird~(-1)-day~(-1)1) were 2.7±0.1 for 5-cluxBLED, 2.6+0.1 for 5-luxBLED, 2.3+0.1 for 5-cluxLED, and 2.1+0.0for 5-luxLED, respectively, corresponding to 8.8-11.2% time spent at the feeders within a day. The DTV (mean +SD, times-bird~(-1)-day~(-1)) and DV (mean +SD, min-visit ') were 80+2 and 2.0+0.1 for 5-clux BLED, 88+2 andl. 8+0.1 for 5-lux BLED, 91+3 and 1.5+0.1 for 5-clux LED, and 95+4 and 1.3+0.1 for 5-lux LED, respectively. Numerically, the broilers tended to visit less to feeders but stay longer at feeders under the chicken-perceived light intensity and broiler specific light spectrum. Feeding behaviors (hourly time spent and times of visit) peaked 2-3 h after initiation of the photoperiod and 2-3 h before theend of the photoperiod. These preliminary observations suggest potential effects of light intensity and spectrum on feeding behaviors of individual broilers, thus providing insights in feeding managements under different light properties. More replicatesare needed to validate the findings.