The experiment was conducted with the objective to evaluate the parameters of dry matter intake, weight gain, feed conversion and energy efficiency of young feedlot steers, fed with two diets that included the AG-2006 sorghum silage harvested with different cutting heights: low cut (14 cm) and high cut (45 cm). Twelve Braford calves with an average age of seven months and average live weight of 208 kg, were used. The feedlot period was 126 days, divided in two period of the 63 days. The roughage:concentrate ratio was 60:40 during the first period and 50:50 during the second period. Silage produced with the higher cut showed lower NDF content (42.57 vs 52.24%) and higher IVOMD (63.67 vs 53.59%). No significant interaction was observed between roughage source and feedlot evaluation period for the consumption of dry matter (DMI) and digestible energy (CDE), expressed in their different forms, for average daily gain (ADG) and feed efficiency (FE). Raising the cutting height from 14 to 45 cm during silage processing, did not affect the DMI (7.60 vs 7.70 kg/day), the CDE (21.62 vs 23.83 Mcal/day), the ADG (1.233 vs 1.375 kg) and the FE (17.53 vs 17.31 Mcal/kg of LW). Steers fed with silage obtained from the 45 cm cutting height were more efficient in converting dry matter intake into weight gain (5.60 vs 6.17 kg of DM/kg LW).
confinament; daily weight gain; dry matter intake; feed conversion; sorghum silage
