The interrelationship between the concentration of ketone bodies, glucose, minerals (Na, K, Ca, Mg, P, Cl) in serum and in TCA soluble whole blood under different physiological conditions in 110 cows was investigated. There was a certain relationship (partly high significant) between the mineral content, ketone bodies and glucose levels in blood. However, there is no clear explanation for the qualification of blood minerals as an indicator of the content of ketone bodies and glucose in serum and whole blood. The age of animals and the seasons had no influence on the concentration of ketone bodies in serum and whole blood. Significant positive relationship was found between the time of lactation, pregnancy and serum glucose and negative relation with ketone bodies. There was no correlation between milk production and ketone bodies. The hours after feeding were positively correlated with ketone bodies.