This trial was undertaken to study the feed intake and the apparent digestibility of the cellular wall constituents and crude protein of canola meal and oat hay, by the total collect of faeces, establishing voluntary intake. The canola meal and canola pelleted in cylinder were used in two levels (15% and 30%/dry matter). The oat hay was triturated in particles of 5 or 10mm. Sixteen male castrated sheeps, native brazilian breed with average weight of 59 kg were used. A completely randomized design was used with 8 treatments and 4 repetitions. The dry matter (DM), crude protein (CP), organic matter (OM), ether extract (EE) and nitrogen free extract (NFE) intake were superior (P < 0.05) in rations containning 30% of canola meal. The crude fiber (CF), neutral detergent fiber (NDF) acid detergent fiber (ADF) cellulose (CEL) and hemicellulose (HEM) intake were similar (P > 0.05) in both levels. The procesing of canola (meal and pellets) and the lenght of oat hay particle (5 ou 10mm) did not influence (P > 0.05) the voluntary intake by sheeps. The DM, OM and HEM apparent digestibilities were similar (P > 0.05) for the rations containning 15 or 30% of canola. The CP, EE and NFE apparent digestibilities were superior (P < 0.05) for the rations with 30% of canola. The CF, NDF, ADF and CEL apparent digestibilities were superior (P < 0.05) for the rations with 15% of canola. The DM, OM, EE, CF NDF, ADF and CEL apparent digestibilities were superior (P < 0.05) for the rations containing pelleted canola. However, the CP, NEE and HEM digestibilities were similar (P > 0.05) between two canola processings forms (meal and pelleted), The DM, CP, OM and EE apparent digestibilities were similar (P > 0.05) between both particle sizes (5 or 10mm). However, the NFE, NDF, ADF and CEL apparent digestibilities were superior (P < 0.05) for the rations with longer hay particles.