Broiler behavioural changes in response to intermittent lighting schedules.

1. Provision of light and dark periods can influence broiler behaviour and impact bird welfare. Determining how offering light in different patterns, such as intermittent (INT) lighting, impacts birds is necessary to determine ideal management practices. The objective of this research was to establish the impact of 9 h of darkness (D) provided in one (1 × 9D), two (2 × 4.5D) and three (3 × 3D) periods on Ross 308 male broiler behaviour.2. Each treatment was replicated three times and behaviour was recorded over 24 h at 32-34 d in one pen per room using infrared cameras. Behaviour was assessed via instantaneous scan sampling at 10 min intervals.3. Birds in the INT treatments spent a lower percentage of time preening. Broilers spent most of their time resting during scotoperiods. The INT lighting schedule birds spent a higher percentage of time feeding and drinking and less time in comfort and exploratory behaviours. Broilers appeared to anticipate all scotoperiods and increased their feeding activity at the beginning of each photoperiod, regardless of period duration.4. Providing 9 h of darkness over 24 h in one, two or three scotoperiods had minor impacts on behaviour. Birds prioritised resting during scotoperiods, while during the shorter photoperiods between scotoperiods birds on INT lighting schedules prioritised nutritive behaviours. Broilers appeared to anticipate the beginning of each scotoperiod and adjusted their feeding behaviour to compensate for time off feed during scotoperiods.