Effects of dietary supplementation with hemp cake and hempseed (Cannabis sativa L.) on the quality parameters and oxidative-antioxidative status of epididymal sperm in rams

Hemp-derived products are increasingly considered as alternative protein sources to soybean meal (SBM) due to their favorable amino acid composition, high digestibility, and potential antioxidant properties. This study evaluated the effect of dietary supplementation with hemp seeds and hemp cake on the quality parameters and oxidative-antioxidative status of epididymal sperm in rams. Twenty-four clinically healthy Polish Lowland ram lambs were assigned to four iso-nitrogenous dietary groups with different inclusion levels of hemp-derived products. The study demonstrated that hemp supplementation had no significant effect on the total motility (TMOT) or velocity parameters of spermatozoa. The sperm collected in the group fed SBM and hemp seeds at a 50:50 ratio exhibited higher straightness ( P < 0.05), while their progressive motility (PMOT) only tended to increase. Hemp-based diets significantly (P < 0.01) improved mitochondrial membrane potential (MMP) and plasma membrane integrity (PMI). Superoxide dismutase (SOD) activity decreased, whereas glutathione peroxidase (GPx) activity and total antioxidant status (TAS) increased in the experimental groups. Moreover, total oxidant status (TOS) and the oxidative stress index (OSI) were reduced, particularly in the group fed hemp cake and hemp seeds at a 50:50 ratio (P < 0.01). The group receiving hemp cake and hemp seeds at a 50:50 ratio also showed a significant increase in MDA concentration (P < 0.05). Hemp-derived products supported sperm membrane functionality and the oxidant-antioxidant balance. These findings suggest that hemp feed ingredients, when included in appropriate proportions, can be effectively incorporated into ram diets and improve epididymal sperm quality parameters. This underscores the need for further research on their long-term effects.