Water and minerals in milk

• The mammary secretary cell cannot synthesize minerals. Therefore, all the minerals in milk are supplied from the blood. The principal mineral contents of milk are calcium, phosphorus, potassium, chloride, sodium, and magnesium.
• The healthy cows without any udder damage there is a constant percentage of sodium, potassium, chloride, and lactose in the milk. They are responsible for keeping the osmotic balance in milk. Water moves into milk to maintain osmotic equilibrium with blood.
• Thus, the secretion of lactose and transfer of sodium, potassium and chlorine into milk determines the volume of milk produced.
• There is as inverse relationship between lactose on one side and sodium & potassium on the other.