Effect of dietary zinc, selenium and their combination on antioxidant parameters in serum and Semen of Sanjabi mature rams

Background: Selenium and zinc play as antioxidants in biological systems, playing important roles in spermatogenesis and protecting against oxidative damage caused by oxygen radicals. This study aimed to investigate the effects of dietary intake of zinc and selenium, either separately or in combination, on antioxidant parameters in the blood and semen of ram. Methods: Twenty mature fat-tailed Sanjabi rams, weighing 50.01 ± 5.6 kg and 20 months of age, were randomly assigned to four different treatments for a period of 120 days (from July to November). The experimental groups included: 1) the basal diet (control group, with 0.11 mg.kg−1 selenium and 20.52 mg.kg−1 zinc) (C), 2) the basal diet supplemented with 0.3 mg.kg−1 selenium (Se), 3) the basal diet supplemented with 40 mg.kg−1 zinc (Zn), and 4) the basal diet supplemented with both selenium (0.3 mg.kg−1) and zinc (40 mg.kg−1) (ZS). Blood samples were collected at eight-week intervals for analysis. Specifically, the levels of total antioxidant status (TAS), malondialdehyde (MDA), glutathione peroxidase (GSH-Px) and zinc (Zn) in serum, as well as GSH-Px, Zn and MDA concentrations in semen were measured. Results: During the first two months of the experiment, the serum total antioxidant status (TAS) in all of the treated animals was significantly higher than that of the control group (P0.05). The serum glutathione peroxidase (GSH-Px) activity was significantly higher in the selenium (Se) group compared to the other groups (P