LED wavelength, lighting intensity, feather coverage, and novelty inclusion in turkey hens

Light-emitting diodes (LED) have been gaining acceptance in agriculture applications as alternatives to incandescent light sources. Daylength intensity and spectral wavelength are important in poultry production and also, in some cases, serve as the only mean of light in some facilities. Therefore, Large White turkey hens of the same strain were reared to market weights using two different housing facilities in combination with different LED light treatments. Each treatment within the environmentally controlled facility (ECF) consisted of four replicate rooms, 16 rooms total in the facility. LED bulbs consisted of 5,000 Kelvin (K) or 2,700K LED in conjunction with a high or low foot-candle (FC) intensity level. Daylength was fixed at 14L:10D. Additionally, birds were reared in a natural curtain-sided facility (6 replicate pens) with exposure to natural light with a 75W incandescent bulb to maintain daylength consistency with the ECF. Performance parameters were measured at 0, 5th, 9th, and 12th week (wk) of age. Serum triiodothyronine (T3) and right eye measurements were taken at the 5th and 9th wk of age. Feather coverage was assessed at the 9th and 12th wk old as indicators of bird wellbeing. Novelty interactions for visual or nutritional items were recorded at 7th wk old. Spectral output within the same Kelvin temperature was significantly altered during dimming to achieve intensity levels. There were mixed performance results; however, cumulatively, birds reared under LED lighting, regardless of LED type or intensity level, had consistently increased body weight. Bird wellbeing was altered under 5,000K LED in combination with 2 FC as measured by a significant elongation of the anterior-posterior distance. However, the same effect was not measured in the 5,000K, 10 FC treatment, or in the 2,700K treatments, regardless of FC measurement. There were no differences among treatments for T3, feather coverage, or latency to approach or interact with novel items. When LED lights are used in environmentally controlled facilities, coupled with novelty interactions, birds maintained and excelled in performance parameters when compared to birds reared with natural light and ventilation conditions.