Impact of Antioxidant–Oxidant Status at Mating on Reproductive Performance of Gray Shirazi Ewes

This study aimed to evaluate changes in oxidant–antioxidant status at mating, mid-pregnancy, and early lactation in Gray Shirazi ewes and to investigate their associations with pregnancy outcome categories, lamb birth weight, parity, and body condition score (BCS). Sixty healthy primiparous and multiparous Gray Shirazi ewes were randomly selected and monitored from mating to early lactation (September ۲۰۲۱–April ۲۰۲۲). Blood samples were collected at mating, mid-pregnancy, and early lactation. Serum concentrations of superoxide dismutase (SOD), glutathione peroxidase (GPX), nitric oxide (NO), total antioxidant capacity (TAC), and malondialdehyde (MDA) were measured using commercial kits. Data were analyzed using repeated-measures and one-way ANOVA followed by LSD post-hoc tests, as well as Pearson correlation analysis (P < ۰.۰۵). SOD activity was significantly higher during early lactation than at the other stages (P < ۰.۰۵), whereas GPX activity was lowest during pregnancy. TAC levels were significantly lower in early lactation than at the other sampling stages. MDA concentrations were highest at mating (P < ۰.۰۵), while NO levels did not differ among stages. At mating, non-pregnant ewes showed significantly higher MDA and NO levels than ewes that later produced single or twin lambs. No significant correlations were observed between oxidative markers and lamb birth weight. However, MDA levels were negatively correlated with BCS during pregnancy (r = −۰.۳۰۱, P < ۰.۰۵). Oxidant–antioxidant status in Gray Shirazi ewes varies across reproductive stages, reflecting physiological and metabolic adaptations. Certain oxidative markers, particularly MDA, TAC, and NO, showed associations with pregnancy outcomes. Monitoring oxidative status at different reproductive stages may contribute to improved management of oxidative stress and reproductive performance in ewes.

کلیدواژه ها:

Gray Shirazi Ewe ، oxidative stress ، Antioxidants ، reproductive performance ، Mating Stage ، Total Antioxidant Capacity