The aim of the study was to investigate the efficacy of Catozal and Kovertal combined with succinic acid for the prevention of pigs with hepatosis. Scientific-production test was performed on the basis of the pig-breeding complex of LLC “Zarechny” of the Republic of Tatarstan. 3 groups of Landrace breed sows were formed on the principle of analogues, 5 animals live weight of 160–180 kg in each group. The first group of sows injected intramuscularly 10 % solution of Katozal in a dose of 5 ml/head for 5 consecutive days 30 days prior to farrowing. The second group was injected intramuscularly Kovertal at a dose of 3ml/head three times a week for three consecutive weeks. Besides, the sows of the first and second groups received daily with wet mash succinic acid at a dose of 20 mg/kg of live mass of 10 consecutive days. The third group served as a control and was kept on a usual diet. The experiment lasted 60 days. The experiment studied the effect of drugs on the clinical condition, the safety and productivity of sows received from these pigs, the natural resistance of sows and their posterity. Studies have shown that the mass of piglets at birth was higher in the first and second experimental groups compared with the control, respectively, 0,14 and 0,17 kg. Phagocytic and lysozyme activity of blood serum, the immunoglobulin content, phagocytic index and phagocytic number were also significantly higher in piglets obtained from sows experienced compared to the control group. Application of Katozal, Kovertal and succinic acid in the diets of sows from the experimental groups allowed for high safety of pigs by 6,0 and 5,9 %. This results from the fact that preparations improve a physiological condition of sows and their posterity.