immediately and pH was measured. Eight milliliters of the rumen liquorwas mixed with 2 mL metaphosphoric acid at 25% to determine VFAand ammonia N. The samples were then frozen at −20◦C until analysis.Volatile fatty acids were analyzed by gas chromatography using the Erwinet al. (1961) technique.Ammonia nitrogen was determined using the McCullough (1967)technique, and concentration was measured through absorbance in anultraviolet light spectrophotometer at 630 nm.