摘要:The aim of this experiment was to study the use of palm oil by products [oil palm fronds (OPF), palm oil sludge (POS) and palm kernel cake (PKC)], that supplemented with Sapindus rarak and Sacharomyces cerevisiae on digestibility and fermentation in vitro . Oil Palm Fronds was previously treated with 3% urea. The treatments consist of 50% OPF+30% POS+20% PKC as a control diet (A), B = A+4% Sapindus rarak , C = A+0.5% Sacharomyces cerevisiae and D = A+4% Sapindus rarak+0.5% Sacharomyces cerevisiae . Digestibility of DM, OM, ADF, NDF, cellulose and rumen parameters (NH3 and VFA) of all treatments were significantly different (p<0.05). Product of fermentation and digestibility treatment A were significantly lower than treatments B, C and D. The result indicated that supplementation Sapindus rarak and Saccharomyces cerevisiae were able to improve fermentability and digestibility of palm oil by product.