Choice Between Fluorescent and Poultry-Specific LED Lights by Pullets and Laying Hens
Light plays an important role in poultry development, production performance, health, and well-being. Light technology continues to advance, and accordingly new light products are finding applications in poultry operations. However, research concerning responses of young and adult laying hens to light sources is relatively lacking. This study assessed the choice between a Dim-to-Red poultry-specific light-emitting diode (LED) light (PS-LED, correlated color temperature or CCT = 2000K) and a warm-white fluorescent light (FL, CCT = 2700K) by pullets and laying hens (W-36 breed) via preference test. Birds with different prior lighting experiences were evaluated for their light choice, including (1) pullets (14 to 16 weeks of age or WOA) reared under incandescent light (designated as PINC), (2) layers (44 to 50 WOA) under PS-LED (LLED) throughout the pullet and laying phases, and (3) layers under FL (LFL) throughout the pullet and laying phases. Each bird category consisted of 12 replicates, three birds per replicate. Each replicate involved a 6-day preference test, during which the birds could move freely between two interconnected compartments that contained PS-LED and FL, respectively. Time spent and feed intake by the birds under each light were measured and then analyzed with generalized linear mixed models. Results showed that regardless of prior lighting experience, birds in all cases showed stronger choice for FL (p = 0.001 to 0.030), as evidenced by higher proportions of time spent under it. Specifically, the proportion of time spent (mean ±SEM) under FL versus PS-LED was 58.0% ±2.9% vs. 42.0% ±2.9% for PINC, 53.7% ±1.6% vs. 46.3% ±1.6% for LLED, and 54.2% ±1.2% vs. 45.8% ±1.2% for LFL. However, the proportions of daily feed intake occurring under FL and PS-LED were comparable in all cases (p = 0.419 to 0.749). The study thus reveals that prior lighting experience of the pullets or layers did not affect their choice of FL versus PS-LED. While the birds exhibited a somewhat stronger choice for FL, this tendency did not translate into differences in the proportion of feed use under each light type.