Nutritional Analysis of Whole Green Crab, Carcinus maenas, for Application as a Fishmeal Replacer in Agrifeeds

Nutritional composition of a composite sample of whole green crabs, Carcinus maenas (L.), was undertaken to evaluate efficacy as a forage fish replacement for seafood-meal manufacture. Whole green crabs sampled from New Hampshire waters were ground together and analyzed for proximate profile (moisture, lipid, protein, fiber, and ash), fatty acid profile, amino acid profile, mineral composition, and mercury content. Green crab mince contained 16.55 ± 0.29% ash, 12.27 ± 0.25% protein, and 0.21 ± 0.07% lipid, and comprised all amino acids essential for chickens and most species of fish. Fatty acid composition of ground green crab was 67.98% unsaturated, and 23.29% saturated, and was richer in eicosapentaenoic acid (EPA) than docosahexaenoic acid (DHA). Levels of mercury in green crab mince were below testable limits. The nutritional profile of green crab mince was evaluated relative to the nutritional profile of menhaden from the literature, and possible agrifeed applications for whole green crab were considered. Green crab showed great potential as a forage fish replacer in seafood-meal applications for chickens and ash tolerant species of fish.