Intensive farming technologies are developed primarily to maximise economic benefits. At the same time, productive animals are often exposed to many stress factors and excessive physiological stress, which subsequently leads to a deterioration in animal welfare, health and, ultimately, a decrease in productive performance. Oxidative stress is one of the most common negative processes that occur in the animal body in the result of various factors, namely, a violation of the pro- and antioxidant balance. This does not occur on its own, but is mainly an accompanying process under the influence of various nature stress factors, such as toxins, temperatures, critical physiological periods, infectious pathologies, excessive, unbalanced or insufficient feeding, etc. This article elucidates the results of the feed additive “Activo” effect studies, that contains secondary plant components of oregano and chilli pepper essential oils on the quantitative content of lipid peroxidation products and the activity of antioxidant defence systems in sows and piglets obtained from them. The study was carried out in the conditions of the industrial complex Barkom LLC, Lviv region. Based on the principle of analogues, two groups of Large White breed gestating sows were formed, 10 animals per group — control and experimental. For the experimental group, the feed additive “Activo” was additionally introduced into the diet in the amount of 0.1 kg/t of finished feed. The content of lipid hydroperoxides and TBA-active products, glutathione peroxidase and superoxide dismutase activity were determined in the blood of sows and their progeny. The results of our studies showed that the use of the feed additive “Activo” for sows and piglets obtained from them is helpful to reduce the negative effects of oxidative stress, which has a negative effect on both sows and their offspring