Calcium is important for bone formation and strength, nerve and muscle function and milk production in nursing mares. It is stored as an important component of the structure of teeth and bones in the form of calcium phosphate. The daily calcium requirement of a horse is about 20 to 35 grams. For pregnant and milk-giving warmblood mares, the requirement increases to up to 60 grams per day. Growing foals also require high amounts of calcium, which are covered in full or in part by the mother's milk until weaning. The supplementary feed of the suckling foals and weanlings should cover the calcium deficit that gradually develops.