Two experiments were carried out to evaluate the additional effects of soybean seeds to the concentrate ration, on apparent digestibility of the nutrients and apparent availability of minerals, and to estimate the apparent digestibility and net energy of corn silage. In the first study eight lactating cows were arranged in two 4x4 square latin design. The addition of raw soybean seeds did not affect the apparent digestibility of the DM and CP, but increased the EE digestibility and reduced the OM and NDF digestibility. However, did not affect the Ca, Mg, K, and Na availability, but the P availability was reduced. In the second experiment, five lactating cows were fed exclusively with corn silage, the DM, OM, CP, EE, and NDF digestibilities were 61.4; 63.8; 42.0; 87.5; and 57.6,%, respectively. It was concluded that corn silage net energy was 1.4 Mcal/kg DM.