A chemical assessment of the diets was conducted, including the levels of DM (dry matter), MM (mineral matter), EE (ether extract) and CP (crude protein), according to the methodology described by AOAC (1990); and NDF (neutral detergent fiber) and ADF (acid detergent fiber), according to Van Soest et al. (1991). OM (organic matter) was obtained by the difference between the MM and the total content of DM (Table I).