The effects of restricting feed quantity and feeder space on the behaviour and production of commercial broiler chickens
Two experiments were conducted to determine the effects of restricting feeder space and feed quantity on the behaviour, production and welfare of three to six week-old commercial broiler chickens. 24 groups of 30 broilers and 24 groups of 10 broilers were used, with each group being exposed to one of nine feeder space/feed quantity treatment combinations. Feeder space treatments ranged from approximately 2.6cm to 7.5cm per bird, while feed quantity ranged from 'ad libitum' to 60% of 'ad libitum'. Results indicate reductions in feeder space and/or feed quantity contribute to increased agonistic behaviour around the feeder. Feeder space restriction is associated with increased group weight variability, decreased feed efficiency, and a reduction in the proportion of birds within a group that attempt to gain access to the feeder. Evidence suggests body weight is a factor in acquiring feed under conditions of severe feeder space and feed quantity restriction.