Marn Nina, Lika Konstadia, Augustine Starrlight, Goussen Benoit, Ebeling Markus, Heckmann David, Gergs Andre
Division for Marine and Environmental Research, Rudjer Boskovic Institute, 10002 Zagreb, Croatia.
School of Biological Sciences, The University of Western Australia, Crawley WA 6009, Australia.
Conserv Physiol. 2022 Sep 20;10(1):coac063. doi: 10.1093/conphys/coac063. eCollection 2022.
Birds build up their reproductive system and undergo major tissue remodeling for each reproductive season. Energetic specifics of this process are still not completely clear, despite the increasing interest. We focused on the bobwhite quail - one of the most intensely studied species due to commercial and conservation interest - to elucidate the energy fluxes associated with reproduction, including the fate of the extra assimilates ingested prior to and during reproduction. We used the standard Dynamic Energy Budget model, which is a mechanistic process-based model capable of fully specifying and predicting the life cycle of the bobwhite quail: its growth, maturation and reproduction. We expanded the standard model with an explicit egg-laying module and formulated and tested two hypotheses for energy allocation of extra assimilates associated with reproduction: Hypothesis 1, that the energy and nutrients are used directly for egg production; and Hypothesis 2, that the energy is mostly spent fueling the increased metabolic costs incurred by building up and maintaining the reproductive system and, subsequently, by egg-laying itself. Our results suggest that Hypothesis 2 is the more likely energy pathway. Model predictions capture well the whole ontogeny of a generalized northern bobwhite quail and are able to reproduce most of the data variability via variability in (i) egg size, (ii) egg-laying rate and (iii) inter-individual physiological variability modeled via the zoom factor, i.e. assimilation potential. Reliable models with a capacity to predict physiological responses of individuals are relevant not only for experimental setups studying effects of various natural and anthropogenic pressures on the quail as a bird model organism, but also for wild quail management and conservation. The model is, with minor modifications, applicable to other species of interest, making it a most valuable tool in the emerging field of conservation physiology.
鸟类在每个繁殖季节都会构建其生殖系统，并经历重大的组织重塑。尽管对此过程的能量细节越来越受关注，但仍不完全清楚。我们聚焦于北美鹑——由于商业和保护方面的利益，它是研究最为深入的物种之一——以阐明与繁殖相关的能量通量，包括繁殖前和繁殖期间摄入的额外同化物的去向。我们使用了标准的动态能量预算模型，这是一个基于机制过程的模型，能够全面描述和预测北美鹑的生命周期：其生长、成熟和繁殖。我们通过一个明确的产卵模块扩展了标准模型，并针对与繁殖相关的额外同化物的能量分配提出并测试了两个假设：假设1，能量和营养物质直接用于产卵；假设2，能量主要用于为构建和维持生殖系统以及随后产卵本身所产生的增加的代谢成本提供燃料。我们的结果表明假设2是更可能的能量途径。模型预测很好地捕捉了普通北美鹑的整个个体发育过程，并能够通过以下因素的变异性来再现大部分数据变异性：（i）卵的大小，（ii）产卵率，以及（iii）通过缩放因子（即同化潜力）建模的个体间生理变异性。具有预测个体生理反应能力的可靠模型不仅与研究各种自然和人为压力对作为鸟类模式生物的鹌鹑的影响的实验设置相关，而且对于野生鹌鹑的管理和保护也很重要。该模型稍作修改后适用于其他感兴趣的物种，使其成为保护生理学新兴领域中最有价值的工具。
