Impact of exercise frequency, race distance, age, and pregnancy stage on oxidative stress and lipid metabolism in purebred Arabian mares.

Abstract: Pregnancy causes increased oxidative stress in mares, possibly harming both the mare and the foal, whereas the effects of different exercise levels on oxidative stress and lipid metabolism during pregnancy remain unclear. Objective: For this reason, the aim of this research was to explore the impacts of different training intensities on oxidative stress and lipid metabolism during pregnancy. Methods: The study comprised 22 clinically normal Purebred Arabian mares from Algeria, which were divided into three groups according to age and exercise frequency. Blood samples were collected during both early and mid-pregnancy stages to assess oxidative stress (ferric reducing antioxidant power, FRAP; thiobarbituric acid reactive substances, TBARS) and lipid metabolism (total cholesterol, CHOL; triglycerides, TG). Results: The results showed a significant increase (P < 0.05) in both FRAP and TBRAS levels during the first trimester of pregnancy in the oldest mares that did not participate in racing. In addition, a positive correlation was observed between FRAP levels and age, as well as between TBRAS levels and the stage of pregnancy. Conversely, FRAP levels were negatively correlated with racing frequency in the studied mares. Conclusions: Oxidative stress levels in pregnant Purebred Arabian mares differed based on age and the level of exercise. Unexercised older mares exhibited increased oxidative stress markers, indicating they are more susceptible to oxidative imbalance during pregnancy.