The effects of thymus plant on digestibility parameters and fermentable methane and CO2 production of some feed by in vitro method

This study was conducted to investigating the effects of adding thymus plant on digestibility and fermentable gas production parameters in some feedstuffs on in vitro status, by 3×4 factorial experiment in complete randomize design. The treatments were wheat straw, alfalfa and barley grain with 0, 1.5, 3, and 6% levels of thymus plant mash. Test gas syringes volume to 100 ml and the incubation time was 24 hours. The result showed that, gas production from the fermentation process rapid part degradation (a) the grain was affected by treatments. Also the gas production rate of slow degradable fraction (b) and potential gas production (a+b) in the wheat straw treatment with increasing of thymus level was decreased. Degradation rate in alfalfa hay treatment with increasing levels of thymus decreased, but in wheat straw were increase. Metabolizable energy and organic matter digestibility of alfalfa hay treated with thymus 6% was significantly lower than other treatments, but the adding most level of thymus increased of metabolizable energy and organic matter digestibility of wheat straw. The addition of different levels of thymus plants to barley grain and wheat straw treatments decreased total gas production compared to the control group. Also addition of thymus plants in rate of 6% significantly decreased the CO2 production compared to the other levels. The amount of methane production from fermentation of alfalfa hay was decreased significantly with increasing of thymus levels compared with control group. The results of this study it can be concluded, the thymus plant additive for ruminant diets can be used as a suitable to optimize rumen fermentation.