UTILIZATION OF DIFFERENT SUPPLEMENTS ON THE PERFORMANCE OF STEERS FED DIETS BASED ON SUGAR CANE

Two experiments, one involving a digestion and nitrogen balance trial and the other, a growing trial, were carried out with the objective to evaluate the effect of different supplements on the performance of steers fed sugar cane as the only roughage. The treatments were: 1 - sugar cane + soybean meal; 2 - sugar cane + urea/ ammonium sulfate + rice bran; 3 - sugar cane + urea/ ammonium sulfate + concentrate A; 4 - sugar cane + urea/ ammonium sulfate + concentrate B. Concentrate A was balanced with ground whole ear corn + soybean meal and concentrate B was balanced with ground whole ear corn + soybean meal + ground rice middling. In the digestion trial, dry matter intake was lower (P< 0.05) for the treatment 2 than 4. Even though differences in the coefficients of digestibility of some components were observed among treatments (crude protein, ether extract, dry matter, energy). The concentration of total digestible nutrients and digestible energy were similar for all treatments. Nitrogen balance date showed that in relation to total nitrogen intake, nitrogen absorbed tended to increase with the addition of urea/ ammonium sulfate, but the proportion of the nitrogen ingested retained tended to decrease. The proportion of the nitrogen absorbed that was retained was higher (P< 0.05) for treatment 1 than for 3. In the growing trial, the animals fed soybean meal presented higher (P< 0.05) dry matter intake, higher (P< 0.05) live weight gain and a better (P< 0.05) feed conversion than animals fed the other three types of supplements in association with urea/ ammonium sulfate.