Effects of Red Osier dogwood (Cornus sericea) inclusion with grass hay on in vitro dry matter disappearance, gas production, and fermentation characteristics

This study evaluated the effects of Red Osier dogwood (ROD; raw or extract) at four inclusion rates (0%, 1%, 3%, and 5% diet dry matter (DM)) on DM disappearance (DMD), gas production (GP) and methane (CH₄) production, ammonia–nitrogen (NH₃–N), and rumen fermentation in timothy grass hay diet in vitro. Supplementation of ROD (irrespective of form) did not affect DMD, GP, or CH₄ production ( P ≥ 0.31) or fermentation parameters ( P ≥ 0.41). No significant form effects or rate responses were observed on the measured gas and fermentation parameters. In conclusion, ROD evaluated in this study did not exhibit potential to mitigate CH₄ emissions in a grass hay diet.