Polymorphisms of the melatonin receptor 1A (MTNR1A) gene affect the sexual performance of Rasa Aragonesa rams without changing their social dominance

This study aimed to investigate whether a specific genotype of the MTNR1A gene influences social dominance and reproductive performance in rams. Thirty-one rams were genotyped for Rsal Mnll polymorphism gene: CC (n=19), CT (n=5), TT (n=7), GG (n=20), GA (n=6), or AA respectively. Maintenance (standing still, lying down, drinking, feeding, walking, stereotyping) behavior (agonistic antagonistic interactions among rams) recorded by direct observations involving instantaneous scan sampling continuous sampling. For each animal, his Index Success (IS) Displacement (ID) calculated. One week after social-behavioral observations, tested individual serving-capacity tests three ewes that synchronized into estrus 15-m2 pen 20 min. The genotypes did not differ number aggressions they performed (CC: 88.95±12.85; CT: 106.20±21.00; TT: 70.43±8.50; GG: 76.05±8.72; GA: 119.00±16.16; AA: 95.80±36.39) received (CC:75.79±5.82; CT:92.40±8.68; 86.14±15.05; 79.25±6.58; 86.83±11.51; 79.80±12.74), their active passive behaviors similar. significantly IS ID, proportion success category was similar groups. polymorphism, responsible 54% 56% sexual events (P < 0.05), Results this confirm best those carried certain gene. Still, it correlated with differences dominance.