Effects of physical feed form and feed particle size on performance, egg quality and nitrogen retention in laying hens

In order to evaluate the effects of feed particle size in pellet and mash diets, 480 Hy-line (W-36) hens at 27 wk of age were assigned to treatments in a 3×2 factorial arrangement with the main factors being mash and pellet feed form, and fine, medium and coarse particle size. Productive traits were recorded during 9 weeks of experimental period and egg quality was measured at the last week of the experiment. In hens fed pelleted diets compared with those on mash diets, feed intake (97.9 and 93.5g, respectively), feed conversion ratio (1.94 and 1.88, respectively), egg weight (58.3 and 57.7g, respectively), body weight gain (73.2 and 38.4g, respectively), Haugh unit (81.5 and 77.5, respectively) and yolk percentage (25.9 and 25.2, respectively) were increased and egg albumen percentage (63.9 and 64.6, respectively) was reduced (P0.05). The main effect and the interaction between feed form and feed particle size for nitrogen retention and excretion was not significant. Result of this experiment showed that FCR was inferior for hens fed pellet compared to mash feeds and increasing corn particle size tended to improve performance parameters.