Avaliação da substituição da silagem de milho por volumoso extrusado na dieta de ovinos

The aim to evaluate the effects of the use of extruded roughage (Urochloa brizantha cv Marandu) to replace corn silage, on dry matter intake and digestibility, ingestive behavior, glycemic curve and blood metabolites in sheep. Twenty Santa Ines ewes, with more three years old and average body weight of 54.5 kg were used, assign in a completely randomized design, with four treatments and five repetitions. The treatments were use the extruded commercial roughage, Foragge® 70% (F) (Nuttrata®) to replace corn silage (S) in the proportions: 20% F and 80% S (20% F: 80% S); 40% F and 60% S (40% F: 60% S); 60% F and 40% S (60% F and 40% S) and 80% F and 20% S (80% F: 20% S). Regression analysis was performed at 5% significance level. As the inclusion of extruded roughage increased, there was an increase in the dry matter intake (DMI), DMI relation to body weight, DMI relation to metabolic weight, weight of feces in natural and dry matter, efficiency of eating, rumination and chewing, urea and blood glucose (P 0.05). The rumination time showed a quadratic response regarding the replacement of corn silage by extruded roughage (P <0.05). It is concluded that the replacement of silage in up to 80% by the extruded volume is recommended, as it improves intake without deleterious effects on digestibility and blood metabolites.