Investigation of the interconnection of the metabolism of Carotine, vitamins A and E in cows at the beginning of the lactation period with the level of beta-hydroxybutyrate

Abstract

This article presents the results of a screening study of the blood serum of cows for the content of carotene in the period of 28-62 days after calving. Out of 31 samples, the results of six samples corresponded to the normative intervals, which amounted to 19.35%. In the remaining animals, carotene was determined in the range from 0.06 to 0.34 mg/dL. In accordance with the obtained data on the concentration of carotene, samples were taken from the sample and 3 groups of animals were formed in such a way that, in an intergroup comparison, Student's t-test was less than 0.001. In the blood serum, a study was made of the concentration of vitamin A, vitamin E and beta-hydroxybutyric acid. Studies have shown that the lowest values of carotene correspond to the minimum concentrations of vitamins A and E. An increase in the level of carotene by 2.36 times to 0.26 ± 0.01 mg / dl is accompanied by an unreliable increase in the concentration of vitamins A and E by 33.3 and 12.8 %, respectively. The highest concentration of carotene in animals of the third group (0.45±0.02 mg/dl) contributes to an increase in the content of fat-soluble vitamins in the blood - A (two times) and E (1.65 times), compared with the indices of cows of the group 1 (both P<0.001).
When considering the content of beta-hydroxybutyric acid in cows, it can be noted that with carotene values below the physiological range in groups 1 and 2, an increase in its concentration above the reference values is observed, while the highest level of carotene corresponds to the concentration of beta-hydroxybutyrate within the normative limits and below, than in groups 1 and 2 by 51.6% and 59.1% (P<0.05). The conducted studies made it possible to determine the high frequency of occurrence of a reduced level of carotene in cows during the milking period, which amounted to 80.65%. The concentration of carotene below physiological limits leads to a decrease in the concentration of important fat-soluble vitamins in the blood, and also contributes to the development of ketonemia.