Previous studies indicated that a diet containing pelleted/crumbled CM increased body weight, live weight gain and feed intake significantly. The improvement in feed intake is probably due to the fact that pelleting and crumbling cause a change in the physical properties of CM, rather than a change in chemical properties. This hypothesis is based on two facts: (1) pelleting/crumbling CM did not increase the dry matter digestibility of the CM based diet (Sundu, et al., 2005) and (2) in this current study, when pelleted / crumbled CM was reground to fine particles and thus bulk density was decreased, all
production parameters were impaired. Since pelleting and crumbling the CM increased the bulk density of the diet by about 30 % in this current study, it is assumed that the bird will spent less time for eating same weight of food (Skinner-Noble et al., 2005) and in the limited space of the digestive organs of young chicks, the bird’s digestive tract can hold 30 % more weight of the crumbled CM diet than it can of the ground pelleted CM diets. An increased feed intake weight consequently would increase the amount of nutrients ingested and would lead to increased growth and body weight.