Farming tambaqui (Colossoma macropomum) using byproducts from the Amazon bioeconomy: nutritional composition, digestibility and attractiveness

ABSTRACT The Amazon bioeconomy produces byproducts that have potential as ingredients in aquaculture feed. This study aims to evaluate nutritional composition, digestibility, and attractiveness of six regional byproducts - Artisanal Fish Waste Meal (FM), Defatted Brazil Nut Meal (BN), Cassava Leaf Meal (CL), Decaffeinated Guarana Bagasse (GB), Defatted Murumuru Meal (MU), and Defatted Ucuuba Meal (UC) - for use as tambaqui (Colossoma macropomum) feed. The byproducts had diverse nutrient profiles, with FM providing significantly more digestible protein and energy, followed by BN and CL. Attractiveness tests indicate that CL and BN are approached more rapidly and consumed more readily. BN and CL have potential as plant-based alternatives, due to their digestibility and attractiveness to the fish. In contrast, GB and UC were limited in both digestibility and feeding stimulation. We suggest that the byproducts FM, BN, and CL can easily be integrated into tambaqui diets, supporting sustainable aquaculture practices in the Amazon. Additional research can determine how to optimize processing and inclusion to fully exploit the functional properties of these ingredients while ensuring cost-effective and environmentally friendly fish farming.