The aim of this work was to evaluate, the replacement of ground or extruded corn by sorghum ground or extruded in the concentrate used in diets for equines. Four mares with an average weight of 450 kg and 24 months of age, non-defined breed were distributed to a 4 × 4 Latin square experimental design in a 2 × 2 factorial arrangement (ingredient - corn and sorghum × processing form - ground and extruded). Apparent digestibility of total diet and nutrients were evaluated, and also the metabolic profile of the animals, considering the values of plasma glucose and insulin after ingestion of diets. Diets with extruded corn and sorghum provided higher total apparent digestibility of dry matter, organic matter, crude protein, neutral detergent fiber and acid detergent fiber higher than those obtained with diets containing these ground ingredients. Total apparent digestibility of starch was similar among diets. Glycemic and insulinemic response was higher when fed extruded diets hence grain processing forms caused changes in the metabolism of horses. Total replacement of corn by sorghum in diets for horses is possible, since the apparent digestibility of nutrients and plasma levels of glucose and insulin did not differ between processing forms of sorghum. Regarding to processing forms, extruded corn and sorghum showed highest starch apparent digestibility and improved the energy potential of the diet.
apparent digestibility; blood glucose; insulin; grain processing
