Energy needs of the cow . The energy demand of the cow increases with increases in milk production. The crude protein needed in the concentrate mix depends on the type of forage in the ration. Forage with high crude protein content such as legumes, can be combined with a concentrate mix of low protein content. However, it is best to adjust the kind and amount of minerals in the ration to the animal's need.
Legumes are rich in calcium and require less calcium supplementation than grasses.
The amount of concentrate in the diet . Usually, concentrates are low in minerals. Thus, the higher the amount of concentrates in a diet, the higher the need for mineral supplementation. The mineral need of the cow . For maintenance, a cow needs 30 to 50 g of calcium and 10 to 30 g of phosphorus per day.