Eight ¾ Indubrazil/Holstein heifers, averaging 160kg, were assigned to 4 x 4 latin squares, during four periods of 21 days, 15days of adaptation and six days of samples collection. The animals were feda diet with 60:40 roughage:concentrate (DM basis), using as roughage sorghumsilage, ensiled with DM content of 30%, and as concentrate, corn and soybeanmeal, with 15.6% crude protein. The treatments were: T1 - control (silage withoutadditive), T2 - silage treated with 2.5% sodium sulfide, T3 - silage treatedwith 2.5% anhydrous ammonia and T4 - silage treated with 2.5% sodium sulfide+ 2.5% anhydrous ammonia, all in dry matter basis, using storage time of sixmonths for all treatments. Dry matter (DM), crude protein (CP), neutral detergentfiber (NDF) and acid detergent fiber (ADF) daily intakes, in percentage of liveweight and metabolic weight, were studied. It was verified effect for all studiedvariables, where the higher intake values were observed for the sorghum silagetreated with ammonia, while sodium sulfide did not show any effect. These valuesshow the anhydrous ammonia efficiency on the action of cell wall constituents,resulting in higher intake.
