The correlations between plasma cholesterol, total lipid concentrations and the qualitative indicators of the ejaculate were investigated in 24 active breeding bulls (13 Holstein and 11 Czech Spotted) over a period of 12 months. No significant differences were observed in cholesterol (3.35 and 3.21 mmol·l^-1, respectively) or total lipid (3.70 and 3.69 g·l^-1) concentrations between the two breeds. The average volume of the ejaculate was 1.15 cm³ higher (i.e. 18.4%) in the Holstein bulls (7.39 and 6.24 ml, respectively). In the 12-month period, a highly significant (P<0.01) correlation was found between the plasma cholesterol concentration and the following indicators: sperm motility (r_p = 0.25), ejaculate volume (r_p = 0.24), and sperm concentration (r_p = -0.25). The correlations between total plasma lipids and the above indicators were: sperm motility (r_p = 0.13), ejaculate volume (r_p = 0.13) and sperm concentration (r_p = -0.11). These values were not, however, significant.