Effect of partial or total substitution of fish meal by poultry by-product meal in diets of juvenile fish Dormitator latifrons (Richardson, 1844)

Objective: The present study evaluated the impact of replacing FM with PBM in balanced diets for Dormitator latifrons, testing four replacement treatments (0, 33, 67 and 100%).Design/methodology/approach: The experiment was conducted using 180 specimens with an initial weight of 33.80 ± 0.08 g distributed in 600 L tanks fed at 2% of their total biomass, for 80 days. Results: The results indicated that the inclusion of up to 33% of PBM did not significantly affect biological parameters compared to the control diet. However, the 100% PBM diet negatively affected blood parameters (such as glucose and protein) compromising the nutritional status of the fish. Although the proximate composition of muscle tissue was similar between treatments, the fatty acid profile showed deficiencies of EPA and DHA in the 100PBM diet, essential for optimal growth and development. Limitations of the study/implications:Poultry by-products represent a viable and sustainable alternative in the formulation of fish diets, with significant economic and environmental benefits. However, their use must be optimized through research that guarantees an adequate nutritional balance.Findings/conclusions: In conclusion, the use of PBM up to 33% as a substitute for FM in the diet of D. latifrons is feasible, maintaining an ade-quate performance without compromising the flesh quality. Higher substi-tutions can impact negatively on both growth and physiological health of fish species, but also the nutritional quality of flesh, highlighting the need to adjust essential nutrient profiles in PBM-based diets. This approach combines sustainability and performance in the aquaculture of this spe-cies