Effect of sequential and intermittent white, green and blue monochromatic lights on productive traits, some immune and stress responses of broiler chickens

Abstract

A study was conducted to investigate the effect of sequential and intermittent white, blue and green monochromatic lights on growth performance, some stress and physiological responses of broiler chickens. A total of 630 day-old broiler chicks (Ross 308) were randomly assigned to 9 light treatments replicated five times with 14 chicks in each replicate. The sequential light treatments included white (WL), green (GL) or blue (BL) monochromatic light throughout the 7-wk experimental period. The intermittent lighting patterns consisted of periodic application of each monochromatic light for the starter (1–14 d), grower (15–28 d) and finisher (29–42 d) phases, resulting in the following light treatments WGB, WBG, GWB, GBW, BWG and BGW, for the starter, grower and finisher, respectively. The light intensity was set at 10 lx/m2 for the entire experimental period and all the birds were offered a corn-SBM based starter, grower and finisher diets for ad libitum consumption. Chicks reared under intermittent lighting pattern of WGB exhibited the highest body weight and the lowest feed conversion ratio (P < 0.05) over the entire production period. The lowest carcass yield (P < 0.05) at 42 d was recorded for birds grown under sequential BL. The intermittent lighting pattern of BWG resulted in the longest tonic immobility time and the highest heterophil to lymphocyte ratio (P < 0.05). Serum nitric oxide was measured to be higher (P < 0.05) at 14, 28 and 42 d in birds reared under sequential WL. Serum T3 and T4 concentrations determined at the end of each period was not statistically affected by the light treatments. The sequential lighting pattern of GL reduced (P < 0.05) serum antibody titers against sheep red blood cell at 30 and 42 d