Temporal variability of illuminance in commercial broiler houses

Abstract

Abstract. Lighting is an essential management tool in poultry production and influences production efficiency through physiological and behavioral responses. Lighting programs for commercial broilers have traditionally prescribed photoperiod and illuminance (intensity). Lighting programs are often tailored by integrators to meet performance goals and minimize adverse behaviors. Ingress of ambient light through ventilation system components can override the prescribed lighting program and has been shown to negatively affect production efficiency. The objective of this study was to characterize temporal variation of illuminance in a commercial broiler house. Illuminance was measured over a six-day period in a tunnel ventilated commercial broiler house in Mississippi using a network of photometric sensors. Three locations were measured along the length of the house: near evaporative pad inlets, mid-house, and near the tunnel fans; sensors were alternately placed near the sidewall (days 1, 3, and 5) and the center-line of the house (days 2, 4, and 6). Results indicate that both illuminance and temporal variability of illuminance were greatest near the tunnel fans as expected. Mean illuminance for the photoperiod was 0.95 and 12.22 lux, for the mid-house and fan locations, respectively and exceeded the target setpoint of 0.5 lux when the lighting system or fans were operating during daylight hours. Temporal variation, as measured by CV, ranged up to 129% at the mid-house location. Given that light ingress increases feed intake and feed conversion, improved control over the light environment in commercial broiler houses can enhance the utility and effectiveness of lighting programs.