Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea.
Department of Agricultural Biotechnology, Seoul National University, Seoul 08826, Republic of Korea; Research Institute of Agriculture and Life Sciences, Seoul National University, Seoul 08826, Republic of Korea.
J Insect Physiol. 2024 Sep;157:104684. doi: 10.1016/j.jinsphys.2024.104684. Epub 2024 Jul 27.
Crickets have been extensively studied in recent insect nutritional research, but it remains largely unexplored how they balance the intake of multiple nutrients. Here, we used the nutritional geometry framework to examine the behavioural and physiological regulation of dietary protein and carbohydrate in nymphs of the two-spotted cricket, Gryllus bimaculatus (Orthoptera: Gryllidae). Growth, intake, utilization efficiencies, and body composition were measured from the eighth instar nymphs that received either food pairs or single foods with differing protein and carbohydrate content. When food choices were available, crickets preferentially selected a carbohydrate-biased protein:carbohydrate (P:C) ratio of 1:1.74. During this nutrient selection, carbohydrate intake was more tightly regulated than protein intake. When confined to nutritionally imbalanced foods, crickets adopted a nutrient balancing strategy that maximized the nutrient intake regardless of the nutrient imbalance, reflecting their omnivorous feeding habit. Intake was significantly reduced when crickets were confined to the most carbohydrate-biased food (P:C = 1:5). When nutrients were ingested in excess of the requirements, the post-ingestive utilization efficiencies of these nutrients were down-regulated, thereby buffering the impacts of nutrient imbalances on body nutrient composition. Crickets reared on the most carbohydrate-biased food (P:C = 1:5) suffered delayed development and reduced growth. Our data provide the most accurate description of nutrient regulation in G. bimaculatus and lay the foundation for further nutritional research in this omnivorous insect.
蟋蟀在最近的昆虫营养研究中被广泛研究，但它们如何平衡多种营养物质的摄入在很大程度上仍未得到探索。在这里，我们使用营养几何框架研究了双斑蟋蟀（直翅目：蟋蟀科）若虫对膳食蛋白质和碳水化合物的行为和生理调节。从第八龄若虫中测量了生长、摄入、利用效率和身体成分，这些若虫接受了具有不同蛋白质和碳水化合物含量的食物对或单一食物。当有食物选择时，蟋蟀优先选择碳水化合物偏向的蛋白质：碳水化合物（P：C）比为 1：1.74。在这种营养选择过程中，碳水化合物的摄入比蛋白质的摄入受到更严格的调节。当局限于营养不平衡的食物时，蟋蟀采用了一种营养平衡策略，无论营养不平衡如何，都最大限度地提高了营养摄入，反映了它们杂食性的喂养习惯。当蟋蟀被限制在最偏向碳水化合物的食物中时（P：C=1：5），摄入会显著减少。当摄入的营养物质超过需求时，这些营养物质的摄入后利用效率会下调，从而缓冲营养失衡对身体营养成分的影响。在最偏向碳水化合物的食物（P：C=1：5）中饲养的蟋蟀发育迟缓，生长速度降低。我们的数据提供了对 G. bimaculatus 中营养调节的最准确描述，并为这种杂食性昆虫的进一步营养研究奠定了基础。
