When they are born, the calves are carefully licked dry by the mother in the box. After a few days they can go outside to the meadow to play and frolic. After a few weeks they also start to eat grass and hay. But they cannot yet digest the green food as well as the adult animals. That is why the calves still drink with their mothers for at least twelve months. After about five years, the calves are mature and can live to be 20 to 25 years old.