Inna Ventsova1*, Vladimir Safonov2

Abstract | The work aimed to evaluate the changes in LPO parameters and the AOP system during adaptation to new living conditions in highly productive dairy cows in the dynamics of dry and postpartum periods. The research was carried out in 2019 in LLC “Ermolovskoe”, Voronezh region, the Russian Federation. A total of 32 heifers and first-calf red-motley Holstein cows of the German selection were included in the experiment. When being transferred to dry cows, catalase activity decreased from 35.8 ± 0.99 μM N2O2 / l-min-103 to 33.2 ± 2.45 μM N2O2 / l-min-103 or by 7.8% after a month and a half, and to 32.4 ± 0.58 μM N2O2 / l-min-103, or by 10.5% (p<0.05), after another week. There was also an increase in triglycerides and cholesterol by 6.7 and 19.1% (p<0.001), respectively. Biochemical studies of various blood parameters have the greatest relevance in controlling the state of animal homeostasis. It has been established that the processes of lipids peroxidation intensify with the increasing pregnancy period in imported heifers and the first days after calving. At that, the AOP indices are quite low. After delivery, the activity of enzymatic and non-enzymatic parts of AOP in the blood of first-calf cows significantly increases, leading to the stabilization and reduction of LPO products. As this work shows, the stress load on the antioxidant system is fairly high in highly productive cows after giving birth and is restored only after 3-4 weeks.

Keywords | Adaptation; Antioxidant protection; Dairy cows; Lipid peroxidation; Screening