Food self selection by commercial laying hens of diets containing different energetic densities

Abstract

With the objective to assess the alimentary behaviour and the zootechnic performance, commercial laying hens were fed with different diets (2,500, 2,800 and 3,100 kcal ME/kg), and in an other group, hens were kept individually and fed with the three diets, simultaneously (Cafeteria system). The birds to the self-selection method of feeding (Cafeteria) showed higher (P < 0,05) intake than the other treatments. Laying percentage was not different between Cafeteria and 2.500 kcal ME/kg groups, but both were different from the other treatments. Feed conversion was not different (P > 0,05) between the energetic levels, but the Cafeteria system showed worse feed conversion. The results for mean egg weight in the Cafeteria system were different (P < 0,05) from that fed ration with 2,500 kcal ME/kg. Shell thickness means were higher for the birds that were fed diets with 2,800 kcal ME/kg, as well as in the Cafeteria system, but these treatments showed lower values for Haugh unit; on the other hand, the results for shell percentage were not different among treatments.