Comparison of Serum Oxidative Status in Healthy Arabian and Dareshoor horses

Oxidative stress, which is an imbalance between the production of oxygen free radicals and the body's antioxidant defense, is strongly associated with physical activity during a horse's life. The aim of the present study was to evaluate the serum levels of Malondialdehyde (MDA), total antioxidant capacity (TAC) and the antioxidant enzymes, superoxide dismutase (SOD), glutathione peroxatase (GPX) and catalase (CAT), and compare them between two races, Arab and Dareshor. For this purpose, 26 non-pregnant and non-lactating female horses from Yazd province (13 Arab and 13 Dareshor) were randomly selected. Blood samples were taken from all horses at rest. MDA, TAC and antioxidant enzymes were tested in the serum of the studied horses.The results showed that the rate of MDA in the Arab race was significantly lower than Dareshor horces (0.98±0.55 vs 1.59±0.56 µmol/L, respectively). Serum TAC concentrations in Arabian and Dareshoor horses did not show any statistically significant difference, although the rate of this parameter in Arabian horses was slightly higher than in Dareshoor (113.54±70.75 vs 112.56±53.93 µmol/L, respectively). In Arab race, level of SOD, GPX and CAT were also higher than Dareshoor. These differences between SOD and GPX enzymes were statistically significant (p < 0.05).High levels of antioxidant enzymes and low levels of MDA indicate better health status for Arabian horses, and breed and genetics appear to play a role in enhancing the strength of the antioxidant defense system.