INFLUENCE OF PARENTERAL APPLICATION OF VITAMINS E, A AND BETA-CAROTENE TO PREGNANT COWS ON SELECTED PARAMETERS IN THE COWS' SERUM AND ON THE QUALITY OF COLOSTRUM.

The aim of the study was to determine the effect of parenteral application of two vitamin preparations to pregnant cows (vitamins E and A to the1^st experimental group, and ß-carotene to the 2^nd experimental group) in the period of 10-14 days before parturition on the following selected parameters in their serum: the levels of vitamins E, A, ß-carotene, total antioxidation status (TAS), haematological parametres, and in their colostrum: vitamins E, ß-carotene, evaluation according to the Brix scale with a refractometer. The cows' blood samples were collected three times: 10-14 days before expected calving, on the day of calving and 7 days after calving. Colostrum samples were collected once, immediately after calving. A statistically significant difference in the ß-carotene levels after parenteral application was observed in the 2^nd experimental group (6.05 µmol l^-1; P<0.01) at the day of calving when compared to the control group (3.61 µmol l^-1), and 7 days postpartum (5.35 µmol l^-1; P<0.001) when compared to the control group (3.41 µmol l^-1). The level of TAS was significant (P<0.001) for this group in the second (0.51 mmol l^-1) and third sampling (0.88 mmol l^-1; P<0.01) when compared with the control group (0.50 mmol l^-1; respectively 0.75 mmol l^-1) and the 1^st experimental group (0.44 mmol l^-1; respectively 0.70 mmol l^-1). There were no significant changes in the level of vitamin E and vitamin A in cow serum, in haematological parametres and in the quality and concetrations of vitamins in colostrum between the groups. The parenteral application of synthetic ß-carotene had an effect on the level of ß-carotene in the 2^nd experimental group and was likely to affect also the level of TAS in this group. On the other hand, the level of vitamin E, A in serum and the quality of colostrum were not influenced by parenteral vitamin application. [ABSTRACT FROM AUTHOR]