Smiley Kristina O, Adkins-Regan Elizabeth
Department of Psychology, Cornell University, Ithaca, NY 14853, USA.
Department of Psychology, Cornell University, Ithaca, NY 14853, USA; Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
Gen Comp Endocrinol. 2016 Aug 1;234:88-94. doi: 10.1016/j.ygcen.2016.03.006. Epub 2016 Mar 7.
Variation in parental care can lead to important fitness consequences. The endocrine system is known to regulate physiological and behavioral reproductive traits that are important contributors to lifetime reproductive success. However, the hormonal basis of variation in avian parental care is still not well understood. Plasma prolactin (PRL) concentrations are generally high during post-hatch parental care in birds, and may be a candidate mechanism that regulates variation in parental care and other reproductive success outcomes. Here we analyze the relationship between PRL, parental behavior (chick brooding and feeding) and reproductive success outcomes (clutch size, number of chicks hatched, and chick survival) for the first time in the zebra finch (Taeniopygia guttata). Birds were given cabergoline, a dopamine agonist traditionally used to lower prolactin in mammals, or vehicle in their food. Cabergoline had no effect on prolactin concentrations, but across both groups we found that PRL is positively correlated with parental behavior, number of chicks hatched, and chick survival, but not clutch size. Results from this study will inform hypotheses and predictions for future manipulation studies which test for a causal role for PRL in parental traits.
亲代抚育的差异会导致重要的适合度后果。已知内分泌系统可调节生理和行为方面的繁殖性状，这些性状是终生繁殖成功的重要因素。然而，鸟类亲代抚育差异的激素基础仍未得到很好的理解。在鸟类孵化后的亲代抚育期间，血浆催乳素（PRL）浓度通常较高，它可能是调节亲代抚育差异及其他繁殖成功结果的一种潜在机制。在此，我们首次在斑胸草雀（Taeniopygia guttata）中分析了催乳素、亲代行为（育雏和喂食）与繁殖成功结果（窝卵数、孵出的雏鸟数量和雏鸟存活率）之间的关系。给鸟类在食物中添加卡麦角林（一种传统上用于降低哺乳动物催乳素的多巴胺激动剂）或赋形剂。卡麦角林对催乳素浓度没有影响，但在两组中我们都发现，催乳素与亲代行为、孵出的雏鸟数量和雏鸟存活率呈正相关，与窝卵数无关。本研究结果将为未来的操纵性研究提供假设和预测，这些研究将检验催乳素在亲代性状中的因果作用。
