Laying hen's behavioural responses and activity indexes to different light colours.

Abstract Information on the subtle changes in behaviour of poultry birds to varying lighting conditions and other environmental factors offers ways to enhance the welfare and egg production. This study examined the effect of light colours on the cumulative activity index and behaviours of 52 Super Nick chickens with the age of days one to 9 weeks old, divided into three pens. Twelve chickens were randomly assigned to the control pen (2 x 2 meters width) with exposure to white light (WL). Twenty hens were randomly distributed to each of the two cages (4 x 4 meters width), where treatment was either exposed to blue (BL) or red light (RL) depending on the lighting schedule. The behaviours were recorded in the morning, midday, and afternoon. The perching sticks were installed in week 5. BORIS software was employed for analysing the videos to label the duration and frequency of the behaviours while Swarmsight program was used to calculate the cumulative activity index. The results showed that cumulative activity index, active behaviours (walking, running, eating, drinking, standing and food pecking), comfort behaviours (perching, wing flapping, body shaking, and head-scratching) were higher (P < 0.05) under WL than under BL and RL. The preening, sitting, and sleeping of the BL group were higher (P < 0.05) than WL and RL. Aggressive and gentle feather pecking frequencies were higher (P < 0.05) in the RL group than in the WL and BL group. The chickens preferred to dustbathe in the afternoon. After the perches were installed, foraging, leg stretching, and standing frequency and the sitting and sleeping duration declined; however, the perching, eating duration and running, food pecking frequency increased. With each passing week, aggressive pecking frequency, walking, perching, and drinking duration increased, but leg stretching and sitting duration declined. The results provide a comprehensive understanding of the influence of light colours on the behaviours of laying hens and thereby offers solutions for designing light-based platforms to enhance welfare.