Abstract:
The aim of this study was to determine the gas production kinetics of wheat straw, alfalfa hay and barley grain and estimate t25, t50, t75 and t95 using Y = A(1-exp(-ct)) exponential model. Gas productions were determined at 0, 3, 6, 12, 24, 48, 72 and 96 h incubation times. At all incubation times gas production of barley grain was significantly (P < 0.01) higher than those of wheat straw and alfalfa hay. The in vitro gas production rate (c) and total gas production (A) of barley grain was significantly (P < 0.01) higher than those of wheat straw and alfalfa hay. Time to produce 25, 50, 75 and 95% of total gas production (t25, t50, t75 and t95) of barley grain also were significantly (P < 0.01) lower than those of wheat straw and alfalfa hay. As a result, in addition to the c and A, using Y = A(1-expct) exponential model the estimation of t25, t50, t75 and t95 will provide more useful data to compare feedstuffs in terms of in vitro fermentation studies.