The activity of the antioxidant protection enzymatic system of boars with a decrease in their reproductive capacity under oxidative stress

It was found that enzymatic system activity of the antioxidant protection of the breeding boars organism with a decrease in their reproductive ability under oxidative stress was significantly decreased, which was noted by a decrease in the antioxidant capacity. Males of the experimental group had a decrease in superoxide dismutase activity by 30,2% (p ˂ 0,01). At the same time, in the erythrocytes of breeding boars, catalase activity was reduced by 33,9% (p ˂ 0,001) compared with the indicators of the control group animals, due to the high sensitivity to nitric oxide, the content of which was significantly increased during oxidative stress; interacting with nitric oxide, a suppressed form of catalase – ferricatalase-NO was formed. A decrease in the activity of these enzymes is characteristic of the oxidative stress development – which is due to the high level of peroxidation processes in the body of breeding boars. With a decrease in the activity of glutathione system components, an imbalance of the prooxidant-antioxidant system was noted. According to the research results, a decrease in the activity of the glutathione redox cycle enzymes – glutathione peroxidase and glutathione reductase was noted, which in boars with a decrease of reproductive ability were also reduced, and this also confirmed the state of oxidative stress. Thus, boars of the experimental group had a pronounced decrease in glutathione peroxidase activity by 28,4% (p ˂ 0,05), while the activity of glutathione reductase in erythrocytes was significantly reduced by 20,2% (p ˂ 0,05). The lack of physiological activity of antioxidant enzymes will have a negative impact on the fertilizing ability of sperm, because the lack of components of the enzymatic antioxidant defence system affects the activity of enzymes in sperm received from the breeding boars. A balance was observed between the components of the enzymatic antioxidant defense: the ratio of antioxidant enzymes’ activity in the male experimental group was lower than the values in the control group, however, the indices of superoxide dismutase/catalase and glutathione peroxidase/glutathione reductase had the same values, indicating that the balance in the enzymatic system of antioxidant defense was maintained. A decrease in enzyme indices in the experimental group indicated a decrease in the antioxidant potential and confirmed a certain state of oxidative stress in the breeding boars organism.