The relatively poor economy in European dairy farming might be improved from efficient feeding systems and dietary management. Increasing herd sizes and transition to loose housing systems in Sweden, increases the possibilities for other feeding systems than separate feeding that is the traditional feeding system in Sweden. Other possible feeding systems are partial mixed ration (PMR) and total mixed ration (TMR), where the TMR system sometimes is associated with overfeeding and thereby increased environmental impact and high feed cost. Diets providing nutrients above or below animal requirements are considered as unbalanced, which in turn are associated with reductions in health, fertility and milk production. On the other hand, a balanced feed ration improves feed efficiency, nitrogen utilization and profitability.