[Content of beta-carotene, vitamin E and ascorbic acid in blood plasma of female calves, cattle, bulls, castrates and ox throughout the course of the year].

The concentration of beta-carotin, of vitamin E and of ascorbic acid in the plasma of female calves (beginning with an age of 4 weeks), of cows in the 2nd and 5th lactation, of bulls, of short scrotum bulls and of oxes in the course of the year was analysed. The concentration of beta-carotin in the plasma of calves after driving up to pasture increased slower than that of cows. After transition to stable feeding there was a significant decrease in the concentration after 4 weeks. During the period of suckling the concentration of vitamin E in the plasma of calves was low. After transition to pasture the concentration of vitamin E in the plasma of calves increased slower than in that of the cows. The concentration of ascorbic acid in the plasma during the winter was higher than during the summer. There was no influence of experimental cryptorchism or castration on the mentioned values.