Estimation of Partial Gas Production Times of Some Feedstuffs Used in Ruminant Nutrition

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.