Seasonal Variation in Antioxidant Defence Biomarkers and <scp>ROMO1</scp> Gene Expression in Relation to Semen Quality of Goat Bucks

The oxidative status of seminal fluid is a critical factor in producing high-quality sperm doses for artificial insemination. This study aimed to investigate the impact of seasonal variations on oxidative stress biomarkers and ROMO1 (Reactive Oxygen Modulator 1) gene expression in Barbari and Sirohi bucks. Four ejaculates of adult breeding Barbari and Sirohi bucks, six from each breed, were collected fortnightly using an artificial vagina during the summer and winter seasons for the study. The redox status of fresh semen samples during the summer and winter seasons was assessed to ascertain oxidative stress in different seasons by evaluating the levels of SOD, CAT, GSH, MDA, and TAC. Spermatozoa were separated from the semen by centrifugation, and ROMO1 gene expression was analysed in both seasons, with GAPDH serving as the housekeeping gene. The results revealed significantly (p < 0.05) higher levels of SOD and MDA in summer compared to the winter season, whereas the catalase activity, reduced glutathione, and mean total antioxidant capacity (TAC) concentration were significantly (p < 0.05) higher in winter than summer in both breeds. While no significant difference was observed for SOD, CAT, GSH, MDA, and TAC between the two breeds. ROMO1, a key protein regulating reactive oxygen species (ROS) generation in mitochondria, especially in metabolically active cells like sperm, showed significantly (p < 0.05) lower expression in winter compared to the summer season. This suggests that the elevated ROMO1 gene expression during summer might influence the antioxidant defence mechanisms in seminal plasma. This study shows that the elevation of ROMO1 gene expression during the summer season influences the antioxidant defence mechanism in the seminal plasma. In conclusion, the findings highlight the importance of considering seasonal factors in managing reproductive health and optimising sperm quality for artificial insemination in goats.