156651 20251017144556.0 doi 10.1016/j.anireprosci.2025.107853 sideral 143964 ART-2025-143964 eng Peña-Delgado, Victoria (orcid)0000-0002-4670-3735 Antioxidant components of ram seminal plasma are influenced by age, season, and the RsaI polymorphism of the MTNR1A gene 2025 Access copy available to the general public Unrestricted Melatonin regulates reproductive seasonality in sheep, and its concentration in the blood plasma is influenced by day length and age. It can act directly or by modulating antioxidant defense enzymes. The RsaI polymorphism (g.17355458 C > T) of the melatonin receptor MT1 gene (MTNR1A) has been associated with changes in ram semen and reproductive behavior. But it remains unknown how age and this polymorphism affect melatonin concentration and the activities of antioxidant defense enzymes in ram seminal plasma. The aim of this study was therefore to analyze the effect of the RsaI polymorphism on melatonin levels and the activities of catalase (CAT), glutathione reductase (GRD), and glutathione peroxidase (GPx) in the seminal plasma of young and adult rams carrying different MTNR1A genotypes. For this purpose, seminal plasma was obtained from 15 young (16-month-old) and 9 adult (5-year-old) genotyped rams, and melatonin levels and CAT, GRD, and GPx activities were assessed for a year. Adult rams had higher melatonin concentrations in their seminal plasma than young rams. Adult CC and CT rams had the highest melatonin levels during the reproductive season, whereas young rams showed no differences between seasons. Adult rams also showed higher levels of GRD and GPx activity during the reproductive season; however, young rams showed higher levels of GPx activity during the non-reproductive season than during the reproductive season. These findings highlight the importance of considering the animal age when analyzing ram seminal plasma and its components. info:eu-repo/grantAgreement/ES/DGA/A07-23R info:eu-repo/grantAgreement/ES/MICINN/PID2020-113239RB-I00 info:eu-repo/semantics/openAccess by-nc-nd https://creativecommons.org/licenses/by-nc-nd/4.0/deed.es info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Carvajal-Serna, Melissa (orcid)0000-0003-3929-5064 Noya, Agustí (orcid)0000-0002-9552-4709 Canto, Francisco Erden, Pelin Abecia, José Alfonso Universidad de Zaragoza (orcid)0000-0003-2827-3054 Pérez-Pe, Rosaura Universidad de Zaragoza (orcid)0000-0002-2312-6402 Casao, Adriana Universidad de Zaragoza (orcid)0000-0003-1997-4262 1002 819 Universidad de Zaragoza Dpto. Bioq.Biolog.Mol. Celular Área Zoología 2008 700 Universidad de Zaragoza Dpto. Produc.Animal Cienc.Ali. Área Producción Animal 277 (2025), 107853 [8 pp.] Anim. reprod. sci. Animal Reproduction Science 0378-4320 1839280 http://zaguan.unizar.es/record/156651/files/texto_completo.pdf Versión publicada 1892149 http://zaguan.unizar.es/record/156651/files/texto_completo.jpg?subformat=icon icon Versión publicada oai:zaguan.unizar.es:156651 articulos driver 2025-10-17-14:13:12 ARTICLE