Twenty apparently healthy, non-pregnant, indigenous adult female horses having same age group (8-10 years) were selected from a stud farm located in Jaipur district of Rajasthan and divided into two groups of ten animals in each . treatment and control group. All the animals were examined for biomarkers of oxidative stress. To study the effect of exercise, all animals of both groups were given trot exercise for 2 hours (for approximately 30 km) for one time. The results of present study revealed a significant (P≤) effect of exercise on malondialdehyde levels only whereas the level of catalase, reduced glutathione and vitamin C revealed a non-significant effect. | Effect of exercise on oxidative stress biomarkers in horses