Reproductive Performance and Catecholamine Responses in Yankasa Rams Supplemented with Synthetic Selenium and Vitamin E in a Semi-arid Environment of Nigeria

ABSTRACT This study investigated the effects of selenium (Se) and vitamin E (Vit. E) supplementation on testicular traits, sperm morphology, and catecholamine responses in Yankasa rams. Sixteen yearling rams (22.5 ± 2.1 kg) were randomly assigned to four treatments and monitored for 9 weeks in a completely randomized design: Control (no supplementation), Se (0.6 mg), Se + Vit. E (0.6 mg Se + 2 g Vit. E), and Vit. E (2 g). Results showed that testicular characteristics were significantly (p < 0.05) higher in the selenium-supplemented group as compared to others. However, the Se + Vit. E group showed significantly lower testicular weights. The various spermatozoa characteristics measured differ significantly (p < 0.05) across the treatment groups except for normal, bent tail, and detached head. The percentage of spermatozoa with proximal droplets was significantly (p<0.05) lower in the Se + Vit. E group compared to others. Microcephalic sperm was absent in treated animals but present in the control (1.5 ± 0.1%) (P=0.019). Catecholamine analysis showed that dopamine was higher (P < 0.05) in the Se + vit. E group as compared with rams in the control and Vit. E groups. Adrenaline (0.45 ± 0.05) and noradrenaline (0.163 ± 0.11) were significantly lower in vitamin E as compared to other treatments. These results indicate that Se alone enhances testicular development, while Se + Vit. E improves sperm quality. However, animals receiving supplements had reduced catecholamine secretion (adrenaline and noradrenaline). KEYWORDS: Catecholamine, reproductive performance, selenium, vitamin E, Yankasa rams