Prior parental experience attenuates hormonal stress responses and alters hippocampal glucocorticoid receptors in biparental rock doves

In the face of challenges, animals must balance investments in reproductive effort versus their own survival. Physiologically, this tradeoff may be mediated by glucocorticoid release by the hypothalamic-pituitary-adrenal (HPA) axis and prolactin release from the pituitary to maintain parental care. The degree to which animals react to and recover from stressors likely affects maintenance of parental behavior and ultimately, fitness. However, less is known about how gaining parental experience may alter hormonal stress responses and their underlying neuroendocrine mechanisms. To address this gap, we measured the corticosterone (CORT) and prolactin (PRL) stress response in both sexes of the biparental rock dove (Columba livia) that had never raised chicks versus birds that had fledged at least one chick. We measured both CORT and PRL at baseline and after an acute stressor (30 minutes restraint). We also measured negative feedback ability by administering dexamethasone, a synthetic glucocorticoid that suppresses CORT release, and measured CORT and PRL after 60 minutes. All hormones we measured when birds were not actively nesting to assess whether effects of parental experience extend beyond the breeding bout. Experienced birds had lower stress-induced and negative-feedback CORT, and higher stress-induced PRL than inexperienced birds. In a separate experiment, we measured glucocorticoid receptor subtype expression in the hippocampus, a key site of negative feedback regulation. Experienced birds expressed higher glucocorticoid receptors than inexperienced controls, which may mediate their ability to attenuate CORT release. Together, these results shed light on potential mechanisms by which gaining experience may improve parental performance and fitness.Funding provided by: National Science FoundationCrossref Funder Registry ID: http://dx.doi.org/10.13039/100000001Award Number: 1846381Funding provided by: Society for Integrative and Comparative Biology (SICB)Crossref Funder Registry ID: http://dx.doi.org/10.13039/100014548Award Number: Funding provided by: Animal Behavior SocietyCrossref Funder Registry ID: http://dx.doi.org/10.13039/100009702Award Number: Funding provided by: Society for Integrative and Comparative Biology (SICB)Crossref Funder Registry ID: http://dx.doi.org/10.13039/100014548Award Number:This dataset includes plasma hormone data collected before and after a classic restraint-stressor in captive rock doves (Columba livia), with information on baseline, stress-induced, and negative feedback/recovery levels of corticosterone (CORT) and prolactin. Additionally, there is a dataset on gene expression of glucocorticoid and mineralocorticoid hormone receptors measured in hippocampi microdissected from brain tissue