The Effect of Beak Length and Condition on Food Intake and Feeding Behaviour of Hens

Abstract: Hens (70 weeks-of-age) with short (10-11 mm), long (13-15 mm) and divided upper beaks (1-3 mm difference in beak length between the left and right sides of the upper beak) were selected from a flock of hens beak trimmed at hatching and re-trimmed at 14 weeks. Hens were switched from a mash diet to various whole grain diets at weekly intervals in order to determine the effect of beak length and condition on food intake, feeding behaviour and particle mix consumed from diets. Birds switched from a mash diet to a mixture of whole grain diets suffered a 22.6 g/day drop (P<0.05) in food intake while, conversely, birds changed from a maize and wheat diet to a sorghum and wheat diet had a 28.4 g/day increase (P<0.05) in food intake. For all diets, birds with short upper beaks consumed 7.8 g/day less (P<0.05) than birds with long upper beaks with divided beak birds intermediate in food intake. Feeding rate of divided beak birds (4.0 mg food/sec) was significantly (P<0.05) less than short beak birds (5.3 mg food/sec) with long beak birds intermediate (5.0 mg food/sec). Birds with a short upper beak made significantly (P<0.05) more pecks at the water nipple than divided beak birds. These studies demonstrated that beak condition of layers has important implications for egg farmers. The performance of birds with short upper beaks might be adversely affected when fed free choice or whole grain diets. Key words: Laying hens, beak trimming, beak length, particle size, feeding behaviou