LIGHT-EMITTING DIODE SPECTRAL SENSITIVITY RELATIONSHIP WITH GROWTH, FEED INTAKE, MEAT, AND MANURE CHARACTERISTICS IN BROILERS

Light-emitting diode (LED) light sources have high potential for replacing traditional incandescent lamps in broiler production. LEDs with short wavelengths (480 and 560 nm) have been reported to stimulate broiler growth. However, short-wavelength stimuli might also have potential negative effects on husbandry workers, which has restricted the application of LED technology to broiler production. In this study, we investigated the effect of human-friendly yellow LED light (580 nm), which is close to the wavelength of 560 nm and acceptable for humans, on broiler growth response. We further evaluated the effects of various LED lights on the feed intake and manure characteristics of broilers. The following seven light treatments were tested: red LED light (R group), yellow LED light (Y group), green LED light (G group), blue LED light (B group), purple LED light (P group), white LED light (W group), and incandescent bulb light (I group). We used a 12: 12 light: dark cycle, as described in our previous study. The feed and water usage of each group were recorded daily, while body weight and manure weight were determined weekly. Manure from each group was sampled for subsequent analysis. We found that the effects of the LEDs on broiler growth were age-related. Broilers in the Y, G, and B groups had similar body weights. However, the relative body weight gain ratio of broilers in the Y group was always greater than those of broilers in the other groups, particularly those in the I group (p = 0.003). The mass ratio of water usage to feed consumption was highest in the R group, whereas the Y group had the lowest mass ratio. Analysis of manure characteristics showed that manure production was positively correlated with feed intake, and broilers in the Y group produced the lowest amount of manure. The water intake of the broilers and the moisture content of the manure were also positively correlated, suggesting that the lower moisture content of the Y group manure might be caused by decreased water intake. These findings suggest that human-friendly yellow LED light might be a good alternative to green LED, blue LED, and incandescent lamps and can successfully be applied to broiler production.