Background and Aim: It is known that metabolic disturbances in the animal body negatively affect parturition, uterine involution, and, ultimately, fertility, especially in cows, during the first insemination. Although the method of diet optimization with the use of a software package results in positive outcomes, adjustment is required for certain groups of animals (e.g., cows), in accordance with the period of the year. Every year, in the spring and autumn, blood is taken from animals to detect metabolic disorders, and then either the diet is balanced or, if the cows lack vitamins and minerals, they are administered to cows parenterally or with food. The aim of this study was to assess the efficiency of using carotene-containing preparation in the prevention of postpartum complications in cows.

Materials and Methods: Before the start of the experiment, blood was collected from the animals of the experimental and control groups, with ten animals in each group, and its serum was examined for the presence of carotene. Low carotene content was found in the serum of all animals (from 0.2 to 0.25 mg%) with the norm within the range of 0.40-0.62 mg%. The cows of the experimental group were injected subcutaneously with the carotene-containing preparation 30, 20, and 10 days before the expected calving date at a dose of 10 mL per head. The carotene-containing preparation was a solution of crystalline β-carotene substance in deodorized sunflower oil. Moreover, the share of β-carotene was at least 0.18%. The drug was administered intramuscularly into the rump.

Results: In the postpartum period, the retention of the placenta was observed in two animals of the control group. The uterine involution in the cows of the control group was 16.0 (p<0.05) days longer than that in the cows of the experimental group. The duration of placenta separation in the cows of the control group was on average 3.21 h longer (p<0.01) than that in the cows of the experimental group. The period from calving to the introduction of the embryo was 63.17±1.56 days in the control group and 48.3±0.83 days in the experimental group. The survival rate of embryos in the cows of the experimental group was 60%, and the period from the calving date to the introduction of the embryo averaged 48 days, which were 14.9 (p<0.05) days less than that in the cows of the control group.

Conclusion: When the carotene-containing preparation was administered in a dose of 10 mL subcutaneously to cows 30, 20, and 10 days before the calving date, the blood carotene content increased, and the duration of the last stage and uterine involution decreased. The period from the calving date to the introduction of the embryo was reduced to 48.3±0.83 days, and the survival rate of embryos was 60%.

Keywords: carotene, diet, embryos, feeding, involution, uterine.