Influence of mineral supplementation on oxidative stress, ovarian follicles growth and reproductive hormone concentration in cyclic Arab mares

Abstract

Objective: To study the effect of minerals supplementation in improving brood mare antioxidant status, ovarian activity and some reproductive hormone profiles. Methods: Five Arab broodmares were supplemented with multi-minerals in their drinking water for three months (Treated) and five control mares received the same ration with no mineral (control) belonging to Police Academy horse stud. All mares were subjected to ovarian ultrasonography and blood sampling at weekly intervals during mineral supplementation. Leptin, estradiol, progesterone and insulin like growth factor-1 were assayed with radioimmunoassay. Mineral concentrations in blood serum were determined using atomic absorption spectrometer. Nitric oxide, lysozymes, total antioxidant capacity and lipid peroxide were also measured. Results: Diameter of the first large follicle (Dominant) and the second large follicle (Subordinate) was higher in treated mares during both estrous and early luteal phases. Moreover diameter of corpus luteum was higher in treated mares compared to control. Mineral supplementation decreased significantly (. P=0.004) levels of leptin but insignificantly improved insulin like growth factor-1 in treated mares. Levels of progesterone, estradiol were insignificantly lower in treated mares. There was a significant increase in levels of lysozymes (. P=0.0001) and total antioxidants (. P<0.006) but a significant decrease in lipid peroxide (. P<0.0001) in treated mares. Nitric oxide did not change greatly by mineral supplementation. Zinc (. P=0.004), copper (. P=0.009), Iron (. P=0.001), cobalt (. P=0.004) and magnesium (. P=0.03) levels were significantly higher in treated mares. Conclusions: Mineral supplementation improved the animals' oxidant antioxidant balance, reproductive hormones and ovarian cyclicity and their supplementation is recommended before any breeding programs.