The invention relates to a ruminant feed supplement for the treatment of milk fever. According to the invention rice bran that has been subjected to a ruminal bypass treatment is used in the feed of dairy cows. The ruminal bypass t reatment may for instance be selected from the chemical cross-lin king, physical cross-linking, coating, or combinations thereof. The invention further relates to the use of rice bran for the manufacture of a composition for the prophylactic treatment of parturient paresis in ruminants, wherein the rice bran has been subjected to a ruminal bypass treatment.
