After birth, the calves are lovingly licked dry by their mothers in their stall. After just a few days, they can join the other cows out on the pasture to frolic around and play. A few weeks later, they start eating grass and hay. However, they still can´t digest the fresh green fodder as well as adult cows. That´s why calves keep drinking their mother´s milk for six to twelve months. They are fully grown by the age of around five, and can live to an age of between 20 and 25.