Nutrient landscape of a cricket nymph: How dietary protein and carbohydrate shape intake, performance, and body composition in the two‐spotted cricket, <scp> <i>Gryllus bimaculatus</i> </scp>

Abstract Understanding the optimal amount and balance of macronutrients required by individual insects is essential for improving the yield and value of insects used as food and feed. Crickets are one of the most widely massproduced edible insects worldwide. Accordingly, there is a growing need to develop dietary formulations that optimize survival, growth, intake, food conversion, and body composition in cricket nymphs. Here, we applied the nutrient landscape approach to examine the combined and interactive effects of dietary protein and carbohydrate on a suite of nutritional traits in eighth‐instar nymphs of the two‐spotted cricket, Gryllus bimaculatus De Geer (Orthoptera: Gryllidae). The crickets were confined to one of 24 chemically defined diets varying in protein‐to‐carbohydrate ratio (P:C = 5:1, 2:1, 1:1, 1:2, 1:5, 1:8) and protein plus carbohydrate concentration (P + C = 21, 42, 63, 84%). Food consumption increased with nutrient dilution, but this compensatory feeding was incomplete. Food utilization efficiency was maximized on nutritionally concentrated diets with a moderately carbohydrate‐biased P:C ratio of 1:1.278. All performance traits were the highest on nutritionally concentrated diets, but each trait was maximized at a different P:C ratio. Cricket nymphs survived best at a highly protein‐biased P:C ratio of 3.861:1. In contrast, both body mass at adult eclosion and relative growth rates (RGR) were maximized at carbohydrate‐skewed P:C ratios of 1:1.473 and 1:1.470, respectively. When offered a food choice, nymphs self‐selected a P:C ratio of 1:1.820, closely aligning with the ratios that maximized body mass and RGR. Body protein content was maximized at a P:C ratio of 1.140:1, whereas body lipid content peaked at 1:5.562. Our results have implications for enhancing the efficiency of cricket farming through diet optimization.