The invention relates to the use of at least one bacterial amylase in combination with a mixture of at least two essential oil compounds selected from the group consisting of thymol, eugenol, meta-cresol, vaniline and guajacol in feed for ruminant animals of the subfamily Bovinae for improving weight gain, milk yield and/or Feed Conversion Ratio (FCR). Examples of bovine animals are beef cattle and dairy cows.
