Studies on Antioxidant Capacity in Selenium-Deprived the Choko Yak in the Shouqu Prairie

The fencing device on pasture has seriously restricted the foraging range in grazing animals. As a result, the incidence of selenium (Se) deficiency is rising in grazing Choko yaks in the Shouqu prairie in Northwest China. To study the effect of Se deprivation on antioxidant capacity in the Choko yaks, the mineral contents in soil, forage, blood, and liver have been analyzed. The parameters of physiology and biochemistry in animal were also measured. The tested results showed that Se contents in soil and forage from tested pastures were very greatly lower than those in the control ranges (P < 0.01), and there were no extreme differences in other elements. Se contents in blood and the liver in tested animals were very extremely lower than those in the control yaks (P < 0.01). Levels of hemoglobin (Hb), erythrocyte (RBC), and hematocrit (HCT) were very extremely less than those in the control group (P < 0.01). Activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD), catalase (CAT), and total antioxidant capacity (T-AOC) in blood from the tested yaks were very much lower than those in the control animals (P < 0.01). Contents of malondialdehyde (MDA) in tested yaks were extremely higher than those in the control animals (P < 0.01). Therefore, it is suggested that Se-deficient forage in natural habitat not only influenced mineral contents in the blood and the liver but also causes serious harm to antioxidant function in the Choko yaks.