Diets based on sugarcane tops silage enriched with soybean silage + concentrate provide greater nutrient intake in relation to diet composed only of sugarcane tops silage + concentrate. Sugarcane tops silage supplemented with protein concentrate or enriched with soybean silage with lower inclusion of concentrate resulted in similar weight gains and feed conversion effi ciency. The use of soybean silage to enrich the protein content of diets consisting of sugarcane tops silage should be based on the cost of protein production in the property through ensiling soybean plant.