Five experimental diets were made (Table 1) with different crude protein (CP) levels, formulated according to the table of ingredient chemical composition, as determined by Furuya (2010). All ingredients were ground to a diameter equal or less than to 0.04 mm. The ingredients were weighed, homogenized and water was added, at a proportion of 20% of the total ration weight. The diets were pelletized in an electrical pelletizing machine and dried in a forced air flow oven (50◦C) for 24 h.