Preference of hens for
high-pressure sodium lighting or low intensity incandescent lighting
C.M. Vandenberg and T.M.
Widowski
University of Guelph,
Guelph, Canada
Domestic fowl are highly sensitive to their visual environment, particularly to light wavelength and intensity. New high-pressure sodium (HPS) light sources emit a much narrower range of wavelengths than traditional incandescent lighting, resulting in light with a yellowish appearance. These HPS lamps may be beneficial to poultry operations due to their energy efficiency and long life spans, however, few studies have investigated its effect on poultry behaviour and performance. The objective of this study was to determine if laying hens were either attracted to or avoided HPS light when given the choice between HPS and incandescent lighting. Twenty Leghorn laying hens were housed in a large floor pen that was illuminated by fluorescent light. The hens were tested in pairs in two experimental chambers. Each chamber contained two rooms divided by an unlit central compartment through which birds could pass freely. Rooms of the chambers were illuminated by either HPS at 426 lux or incandescent lighting at 27 lux. These lighting levels approximated those being tested on commercial farms in another study. Each chamber room had an identical feeder, drinker and nest box on wood shavings. Pairs of birds were tested during six-hour periods on two consecutive days. Lighting sources were switched on the second day to control for any room preferences birds might have had. The birds were video recorded continuously during the tests. At four-minute intervals the location and activity of each bird was recorded. The hens spent similar amounts of time in the two light sources (P>0.10) indicating that the hens were neither attracted to nor did they avoid the brighter HPS source. However, the hens spent more time sitting and feeding than expected in the dimmer incandescent light (P<0.05) and more time pecking, nesting and preening than would be expected in HPS (P<0.05). These differences in behaviour may have been due to differences in intensity or colour between the two light sources. Additional studies should be conducted to determine how illumination of poultry houses with HPS affects overall behaviour.