Performance, behaviour and welfare aspects of broilers as affected by different colours of artificial light

Abstract

This experiment examined the effect of four colours of artificial light (ALC) on performance, behaviour, water/feed intake (WFI) and welfare of broilers. Day old broiler chicks (Cobb) were assigned into six brooders for either red (RD:650-750nm), white (WT:325-750nm), green (GR:530- 545nm) or blue (BL:450-470nm) ALCs from 1- 35d (20lux,9hrs/day at growing stage). Complete Randomize Design was adopted with 6 replicates. Water and Feed provided ad libitum. Daily WFI; weekly weight gain (WG) and behaviour recorded. Common behaviours (21) were evaluated by scan sampling method. Welfare indicators; foot pad dermatitis, breast blisters and hock burning damage scores were determined. Lameness was assessed by gait score and latency to lie (LTL) tests. Six birds/ treatment were evaluated for carcass parameters. Significantly (p<0.05) highest WG (365.33±12.07g/bd/ week) was recorded in RD compared to other treatments at 21d. Also Significantly highest WI (102.07±49.01 g/bd/day) at 21d and FI(226.48±27.47) at 28d were recorded by RD treated birds. ALC had no effect on final body weight (BW), feed conversion ratio (FCR), water feed ratio (W:F ratio), welfare indices, mortality rate, carcass parameters, gait score and LTL. Overall, the dominant behaviour was lying that showed 64.15% of the total time budget. Wing flapping (26%) and eating (6.98%) received 2nd,3rd places, respectively. ALC significantly (p<0.05) affected sleeping behaviour (SL) where RD treated birds performed the highest (0.53%±0.29) and GR treated birds showed lowest (0.31%±0.19) SL. Birds were more active under RD, WT and GR compared with BL in the night as lowest eating and walking performed by BL treated birds. Highest dust bathing shown by the birds under GR during morning at the 4th week (0.02%±0.02).Though ALC had no effect on eating, ALC*night time interaction demonstrated increased (p<0.05) eating in RD and WT at night. These data indicate that rearing ALC affected bird behaviour than growth. Providing RD colour light up to 21d had beneficial effects on weight gain.