EN
From the second week after calving to the 120th day of lactation a mineral-fat (PMT) supplement was used in feeding high yield cows; group I - 1.1 kg, group II - 0.8 kg daily per animal. In the first four months of lactation, a statistically significant higher daily milk yield was noted from cows from the experiment groups as related to those from the control group (ca. 1.5 kg daily). In the group where the dose of the supplement was lower, the amount of lactose and fat in milk was significantly higher (0.29%). This resulted in a higher FCM milk yield (ca. 2.60 kg daily). No significant influence of PMT on other milk components, its technological parameters, content of fatty acids nor the biochemical parameters of the serum of the cows was noted. The analysis of yield and the parameters of milk and blood indicates that the amount of PMT in the daily feed doses should not exceed 0.8 kg per animal.