EN
The studies were carried out on 20 dairy cows assigned to two groups depending on their blood serum content of ketonic compounds. The cows of group I, which had subclinical ketosis, were administered Col press supplement to feed ration, whereas the cows of group II were the control group. Col press was applied from seven days before expected parturition through four weeks postpartum. In the blood serum of all the animals, the following were determined: level of ketonic compounds, glucose, total protein and its fractions, activity of enzymes (AST, ALT, ALP and GTP) and concentration of macroelements (Ca, P inorganic, Mg, Na, K and Cl). ABB parameters were analysed in whole blood. The blood tests were done four weeks before expected parturition, and one week and four weeks after parturition.