The nutritional ecology of maturation in a carnivorous insect
The nutritional ecology of maturation in a carnivorous insect
复制标题
DOI：
10.1093/beheco/ary142
复制
发表时间：
2019-01-01
影响因子：
2.4
通讯作者：
Cotter, Sheena C.
中科院分区：
文献类型：
--
作者：
Al Shareefi, Ekhlas;Cotter, Sheena C.
面对营养复杂的饮食，草食动物和杂食动物已经进化出平衡特定营养素摄入量的能力。最近的研究发现，食肉动物也有这种能力，尽管它们的饮食营养更加均匀。然而，与草食动物和杂食动物在限制不平衡食物时优先考虑蛋白质摄入不同，食肉动物对脂肪摄入表现出更严格的监管。当无法达到摄入目标时，这些过度或摄入营养不足的选择被称为妥协规则。迄今为止，检查这些规则的研究都是在单一生命阶段进行的，目前还不清楚这些关于营养素优先顺序的规则是固定的还是不稳定的。我们用肉食性甲虫 Nicrophorus vespilloides 来解决这个问题。我们结合饮食限制和选择测试来确定生殖成熟甲虫和正在经历成熟喂养期的新出现的成虫的摄入目标和妥协规则。我们表明，尽管两个生命阶段的摄入目标非常相似，但折衷规则却有所不同。尽管成熟的成年人遵循典型的肉食动物的脂肪优先规则，但未成熟的成年人的行为更像杂食动物，对蛋白质摄入量表现出严格的控制，当限制蛋白质缺乏的饮食时会导致肥胖。这些替代规则表明在这些生命阶段应对过量蛋白质的不同机制或能力。研究不同生命阶段的摄入目标和妥协规则如何变化可能是我们了解动物在快速变化的环境条件下如何生存的一个有价值的方法。
Herbivores and omnivores, faced with a nutritionally complex diet, have evolved the capacity to balance the intake of specific nutrients. Recent studies have found that carnivores also have this capacity, despite their more nutritionally homogeneous diet. However, unlike herbivores and omnivores who prioritize protein intake when restricted to imbalanced foods, carnivores instead show much stricter regulation of fat intake. These choices to over- or under-consume nutrients when the intake target cannot be achieved are known as rules of compromise. To date, studies examining these rules have all been carried out at a single life stage, and it is unclear if these rules regarding the prioritization of nutrients are fixed or labile. We address this question with a carnivorous beetle, Nicrophorus vespilloides. We use a combination of dietary restriction and choice tests to determine the intake target and rules of compromise in reproductively mature beetles and in newly emerged adults undergoing a period of maturation feeding. We show that, despite having very similar intake targets, the rules of compromise differ between the 2 life stages. Although mature adults follow the typical carnivore rule of fat prioritization, immature adults behave more like omnivores, showing strict regulation of protein intake, resulting in obesity when restricted to protein-poor diets. These alternate rules suggest different mechanisms or capacities to cope with excess protein across these life stages. Examining how intake targets and rules of compromise change across life stages could be a valuable approach for our understanding of how animals will fare under rapidly changing environmental conditions.