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

Abstract

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 and Mnll polymorphism of the gene: CC (n=19), CT (n=5), and TT (n=7), and GG (n=20), GA (n=6), or AA (n=5), respectively. Maintenance (standing still, lying down, drinking, feeding, walking, or stereotyping) and social behavior (agonistic and antagonistic interactions among rams) were recorded by direct observations involving instantaneous scan sampling and continuous behavior sampling. For each animal, his Index of Success (IS) and Displacement (ID) were calculated. One week after the social-behavioral observations, rams were tested in individual serving-capacity tests involving three ewes that were synchronized into estrus in a 15-m 2 pen for 20 min. The genotypes did not differ in the number of aggressions they performed (

Association of melatonin receptor 1 A with litter size in sheep: A review

“…5,22 Despite the fact that the ramifications of the MTNR1A gene on reproductive seasonality have only been investigated to a limited extent up until this point, those studies have shown that these effects are tied to three specific mutations discovered in exon II at locations 606, 612, and 706, 7,21 only sheep of the Sarda and Aragonese breeds have had the remaining portions of this gene examined. 12,13,[23][24][25] Mechanisms Involved in the Production and Secretion Control of Melatonin The pineal gland predominantly secretes melatonin during nocturnal hours, thereby designating this hormone as an inherent informant of the photoperiodic trend. 26 The circadian influence of melatonin is orchestrated through melatonin receptors located in the hypothalamic suprachiasmatic nucleus, the central hub of the circadian clock.…”