Dietary carotenoid supplementation facilitates egg laying in a wild passerine

During egg laying, females face a trade-off between self-maintenance and investment into current reproduction, since providing eggs with resources is energetically demanding, in particular if females lay one egg per day. However, the costs of egg laying not only relate to energetic requirements, but also depend on the availability of specific resources that are vital for egg production and embryonic development. One of these compounds are carotenoids, pigments with immuno-stimulatory properties, which are crucial during embryonic development. In this study, we explore how carotenoid availability alleviates this trade-off and facilitates egg laying in a small bird species, the blue tit (Cyanistes caeruleus). Blue tits have among the largest clutch size of all European passerines and they usually lay one egg per day, although laying interruptions are frequent. We performed a lutein supplementation experiment, and measured potential consequences for egg laying capacity and egg quality. We ...

雌性个体在产卵期间会面临自身维持与当前繁殖投入之间的权衡取舍：为卵提供营养资源的过程在能量上消耗巨大，若雌性每日产一枚卵则此种消耗尤甚。不过，产卵的代价不仅与能量需求相关，还取决于卵生成与胚胎发育所必需的特定资源的可获得性。这类必需资源中的一类为类胡萝卜素（carotenoids）：这类色素具有免疫刺激特性，在胚胎发育过程中至关重要。本研究以小型雀鸟物种大山雀（Cyanistes caeruleus）为研究对象，探究类胡萝卜素的可获得性如何缓解上述权衡并助力产卵过程。大山雀是所有欧洲雀形目鸟类中窝卵数最大的物种之一，尽管其产卵中断现象较为频繁，但通常每日产下一枚卵。本研究开展了叶黄素（lutein）补充饲喂实验，并测定了其对产卵能力与卵品质的潜在影响。我们...