Body mass and clutch size may modulate prolactin and corticosterone levels in eiders.

摘要: Altered body condition, increased incubation costs, and egg loss are important proximate factors modulating bird parental behavior, since they inform the adult about its remaining chances of survival or expected current reproductive success. Hormonal changes should reflect internal external stimuli, corticosterone levels (inducing nest abandonment) known to increase while condition deteriorates, prolactin (stimulating incubation) decrease following predation. However, in a capital incubator that based investment on available reserves naturally lost half mass during incubation, be maintained at low threshold avoid protein mobilization for energy supply. This study focused regulation release such birds when facing manipulation (control, reduced, increased) stressful event. Blood samples were taken before after clutch hatching. Corticosterone determined 30 min captivity. Female eiders exhibited high hypothalamic-pituitary-adrenal sensitivity, plasma concentration being by four- fivefold The adrenocortical response was not modified but higher which size increased. In same way, females did show different among experimental groups. started, correlated mass, suggesting attendance is programmed relation female initial condition. Moreover, due an artifactual impact manipulation, baseline associated with control group. These data suggest that, eiders, modification can modulate levels, cross-regulate each other order finely behavior.