The effects of the monensin supplementation on the ruminal parameters and digestibility were evaluated after 120 days of trial, using 20 Holstein bull calves with average weight and age of 90.8 kg and 80 days, respectively. The treatments were 0, .4, .8 and 1.2 mg of monensin/kg LW. As the monensin levels increased the pH values increased (5.97, 6.14, 6.36, and 6.48), but N-NH3 (45.54, 38.08, 28.39, and 24.17 mg%), acetate (36.55, 33.72, 35.62, and 26.35 mM), butyrate (1.22, 7.27, […]