A Sustainable Diet for Tambaqui Farming in the Amazon: Growth Performance, Hematological Parameters, Whole-Body Composition and Fillet Color

Abstract

The aim of this study was to produce feed based on locally sourced ingredients for tambaqui farming in Amazon. Diets were formulated with increasing levels (0, 25, 50, 75 and 100%) of defatted black soldier fly larvae meal (BSFL) as a replacement for fish meal (FM), and cassava by-products in the same proportion (tuber residues, peel and leaves). A conventional diet (CO) was used as the control. Juvenile tambaqui (24.61 ± 1.14 g) were housed in 24 tanks in a recirculation aquaculture system. Neither diet rejection nor mortality were observed. Fish fed cassava by-products showed similar feed conversion rates (FCR 1.76); however, these values were worse than those observed in fish fed the CO (FCR 1.33). No differences were observed in the whole-body composition of the fish. The fillets of fish fed cassava by-products had a yellow color due the carotenoids present in the leaves. Dietary BSFL and cassava by-products can contribute to the sustainability of Amazonian aquaculture. Further studies with a lower proportion of cassava leaves in the diet formulation are recommended so as to ensure enhanced diet digestibility and less impact on the color of the fillets.