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.