Impact of light intensity or choice of intensity on broiler performance and behavior

Abstract

The optimal light intensities for broiler production and well-being have been investigated for some time. The use of a minimum 20 lux (lx) is mandated within the European Union (European Commission, 2000; European Union 2007). Light intensities below 20 lx are commonly used in the United States. There have been inconsistent effects of light intensities below 20 lx on broiler performance. The present study evaluated the performance of broiler chickens reared under 5, 10, and 20 lx or a choice between these intensities. The feed: gain ratio was the lowest for birds reared using 5 lx and the choice of 5, 10, and 20 lx (1.71 and 1.70) compared to 20 lx (1.81), with 10 lx being intermediate (1.74). Furthermore, there were no differences observed in carcass yield, breast yield or abdominal fat. Preference for different light intensities (5, 10, and 20 lx) was examined using a remote video system. On d 20, more birds were observed to be feeding under light intensities of 10 and 20 lx compared to 5 lx. All other (not feeding) birds preferred 20 lx on d 20. On d 31 birds feeding no longer displayed a preference while all others preferred 10 and 20 lx over 5 lx. On the final observation d 41 only those birds not feeding or drinking showed a preference for 10 lx. The results agreed with past studies in demonstrating the change of preference for light intensity. The use of choice lighting environments was able to provide the desired light intensity of broilers at a young age while maintaining production parameters of those reared using low intensity (5 lx).