Antioxidant status of piglets under nitrate-nitrite load and the action of corrective factors

Abstract

The article presents the results of research on the state of the antioxidant defense system of piglets under nitrate-nitrite toxicosis and the action of corrective factors (methionine, phenarone and methyphene). Nitrate-nitrite load in piglets caused inhibition of the activity of enzymes of the antioxidant defense system, that indicates a decrease in the activity of superoxide dismutase, catalase and glutathione peroxidase in the serum of testing animals. The lowest activity of antioxidant enzymes under chronic nitrate-nitrite toxicosis was on the 60th day of the experiment in the serum of piglets of the control group, where accordingly the activity of superoxide dismutase decreased by 14 %, catalase activity – by 18 %, glutathione peroxidase activity – by 12 %. Lipid peroxidation processes are activated in the blood of animals, namely the level of lipid hydroperoxides and diene conjugates increases under the conditions of experimental nitrate-nitrite load. It should be noted that the highest level of lipid peroxidation products in the serum of piglets with chronic nitrate-nitrite toxicosis was on the 60 th day of the testing, and accordingly the content of lipid hydroperoxides increased by 67 % and diene conjugates – by 33 %. Administration of methionine, phenarone and methyphene under nitrate load contributed to the activation of the antioxidant defense system compared to animals in the control group. The use of antioxidant drugs in sick piglets also contributed to the inhibition of lipid peroxidation, as indicated by a decrease in the content of lipid hydroperoxides and diene conjugates in the serum of experimental group. More pronounced antioxidant effect was shown by administrating methyphene. The mechanism of action of phenarone and methyphene is associated with the direct effect of its components on the inhibition of the absorption of metabolites that have a toxic effect on cell membranes of animals. As a result of the adsorbing action of zeolite, which is part of the drugs, in the digestive tract there is a decrease in the concentration of substances that can be substrates for lipid peroxidation, as well as removal of toxic metabolites in the blood, which are prooxidants. This process occurs by osmosis and diffusion of these substances through the capillaries of the microvilli of the small intestine and their subsequent fixation on the sorbent granules.

Keywords

• toxicology, antioxidant defense system, nitrates, nitrites, piglets