Insulin‐like growth factor 1 and growth rate in nestlings of a wild passerine bird

摘要: Summary Post-natal growth rate is an important life-history trait that strongly associated with survival during the transition to independence and overwinter period. In laboratory conditions, insulin-like factor 1 (IGF-1) has been shown be one of main hormones regulating development in maturing vertebrates. However, extent which plasma IGF-1 enhances free-living animals, particularly birds, still unclear. In this study, we used brood size manipulation great tits (Parus major) investigate how changes nestling nutritional condition post-natal are related levels. Nestlings reduced broods had increased rate, better body also higher levels prior fledging than those control enlarged broods. Plasma were middle period, when most rapid, pre-fledging stage. Our results suggest varies depending upon resource (e.g. food) availability potentially plays role wild passerines a time-specific manner.