Is press cake a sustainable Swedish-made roughage and protein supplement for horses? At Axevalla Hästcenter in Skara, feed trials are being conducted to develop an environmentally friendly protein feed for horses. Researchers at SLU are using a press cake consisting of silage grass that has been pressed in the green biorefinery at the Naturbruksskolan Sötåsen i Töreboda. The feed trials are part of our EU-funded project in which several actors are participating to develop green biorefining.