Pavlata L., A. Pechova, R. Dvofiak: Microelements in Colostrum and Blood of Cows and their Calves during Colostral Nutrition. Acta Vet. Brno 2004, 73: 421-429. The goal of the study was to use evaluation of blood and colostrum selenium (Se), copper (Cu) and zinc (Zn) concentrations of cows and the same blood concentrations of calves during the period of colostral nutrition to study differences in the metabolism of the different microelements in the mother and its young. Blood was collected from 12 cows and their calves before first intake of colostrum on the calving day and then at the end of the period of colostral nutrition to determine Se, Cu and Zn concentrations. First colostrum was collected from all cows. Se concentration was determined from whole blood and colostrum samples using hydride technique AAS. Cu and Zn concentrations were determined from colostrum and blood serum using flame AAS. The cows under examination were shown to have average concentrations of Se of 0.87 ± 0.30 and 0.47 ± 0.15 µmol·l -1 in whole blood and colostrum respectively, of Cu 8.95 ± 1.95 and 5.37 ± 1.80 µmol·l-1 in blood serum and colostrum respectively, and of Zn 11.62 ± 2.35 and 416.76 ± 120.07 µmol·l -1 in blood serum and colostrum respectively. Blood of calves before the first intake of colostrum was characterized by a significantly higher ( p < 0.001) mean concentration of Zn (25.88 ± 8.79 µmol·l -1 ) and a significantly lower ( p < 0.001) concentration of Cu (3.23 ± 1.08 µmol·l-1) compared with the mothers. Blood Se concentration of the calves (0.91 ± 0.26 µmol·l-1) was not significantly different from blood Se concentration of the cows. A significant increase ( p < 0.001) in blood Cu concentration of the calves to 7.53 ± 1.98 µmol·l-1 and an insignificant increase in the mean Zn and Se concentrations to 26.40 ± 6.58 µmol·l -1 and 0.93 ± 0.32 µmol·l -1 respectively occurred during colostral nutrition. Correlation analysis showed a significant correlation ( p < 0.01) between blood Se concentrations of the mothers and their newborn calves (r = 0.72). No significant correlation was found between Cu and Zn concentrations of cows and their calves. No significant relation between blood and colostrum concentrations of the different microelements of cows was found either. We have shown major differences as to the parameters of the micromineral metabolism under examination at the level of the mother/young relationship. While the calf organism can accumulate Zn throughout the intrauterine development and Zn is cumulated in cow colostrum, too, serum Cu concentrations of newborn calves are significantly lower compared with the mothers and colostrum Cu concentrations reach just about 60% of serum Cu concentrations of the cows. Although blood Cu concentration of calves increases throughout the period of colostral nutrition, it does not reach the level of serum Cu concentration of the mother by the end of the period. The Se status of newborn calves is similar to that of the mother cows and just like with Cu, Se is not cumulated in colostrum to any significant extent. Selenium, zinc, copper, placental transfer, cattle, metabolism, mother-young relation Selenium (Se), copper (Cu), and zinc (Zn) are microelements ranking among substances with biological activity in intermediate metabolism. They get into the organism mainly as components of animal diet and their transplacental transfer is an important factor in the young. The level of absorption and retention of microelements is modulated by their actual levels in the organism and their concentrations in the diet and is generally higher for intake of their organic forms ( Knowles et al. 1999; C a o et al. 2000; Pavlata et al. 2001;