RESUMO
The antioxidant properties and the protective role of organic zinc (Zn) and copper (Cu) in white blood cells (WBCs) and spermatozoa were analyzed through quantification of superoxide dismutase 1 (SOD1), catalase (CAT), glutathione peroxidase 4 (GPx4) and nuclear factor erythroid 2-like 2 (NFE2L2) and correlations were determined with sperm functional characteristics in Osmanabadi bucks. Bucks (aged 5 months; n = 40) were divided into ten groups, and the dietary treatments comprised of a control and nine treatment groups as follows: organic Zn as Zn 20, Zn 40 and Zn 60, organic Cu as Cu 12.5, Cu 25, Cu 37.5 and combined organic Zn and Cu as Zn 20+Cu 12.5, Zn 40+Cu 25, Zn 60+Cu 37.5, respectively per kg dry matter for a period of 8 months. The blood (120 and 240 days) and semen (240 days: 40 × 4 = 160) samples were collected from 40 bucks. In WBCs: the relative abundance of mRNA for SOD1, CAT, GPx4, NFE2L2 was greater (P < 0.05) in (120 and 240 days) in majority of the mineral supplemented animals. In spermatozoa: the relative abundance of SOD1, NFE2L2, GPx4 and CAT mRNA was greater (P < 0.05) in selected treatment groups. The abundance of SOD1 mRNA in WBCs was positively correlated (P < 0.05) with sperm mass motility (r = 0.692, P = 0.027). The abundance of GPx4 mRNA was negatively correlated (P < 0.05) with type A sperm (straightness; STR) > 85% and amplitude of lateral head displacement (ALH) > 2.5 µm/ s) (r = -0.711, P = 0.021) and (P < 0.05) positively correlated with sperm viability (r = 0.669, P = 0.035). Organic Zn and Cu supplementation was associated with an increase in the expression of antioxidant defense enzyme genes in bucks.
