Administering a bolus to a ruminant animal, comprises administering a first bolus to the ruminant via oral route, where the first bolus is in the form of an anhydrous solid tablet comprising calcium formate, an organic acid different from formic acid, and a basic source of calcium, falls and dissolves in ruminal juice of rumen of the ruminant animal so that calcium formate is absorbed by the ruminal wall, and the organic acid reacts with the basic source of calcium to form an organic salt of calcium that is absorbed by the ruminal wall. An independent claim is also included for a bolus in the form of an anhydrous solid tablet for administration to the ruminant animal, comprising calcium formate, organic acid and the basic source of calcium that reacts in the presence of water with the organic acid to produce the calcium salt. ACTIVITY : Metabolic Antipyretic. MECHANISM OF ACTION : None given.
