The aim of this study was to determine the effect of selenium concentration in blood and milk in early lactation on somatic cell count. The average selenium concentration in the blood serum was 0.62 ± 0.11 μmol/l and in the milk serum 0.61 ± 0.07 μmol/l. Optimal blood selenium concentrations were found in 19 cows and suboptimal concentrations in 11 cows. Optimal milk selenium concentration was found in 14 cows and suboptimal in 16 cows. The average milk production per cow was 23.12 ± 3.1 liters / day and the average somatic cell count in the first and sixth months of lactation was 5.34 ± 5 (log transformed) and 5.12 ± 4.9, respectively. Blood selenium concentration correlated negatively with milk somatic cell count in early and mid lactation. The classification of cows based on blood selenium concentration gave results which suggested that selenium-deficient cows had a significantly higher somatic cell count in early lactation (the first month) and mid lactation (the sixth month). Blood selenium is an important predictor of milk somatic cell count. Somatic cell count in milk is not dependent upon selenium concentration in milk or interaction blood×milk selenium. Selenium concentration is not in connection with milk production
