Optimal inclusion of recycled food waste materials supplemented with lysine, and methionine in the practical diet of Nile tilapia Oreochromis niloticus fry

Abstract

This study evaluates the optimal inclusion of recycled food industry waste (FIW) and soy sauce waste (SSW) supplemented with lysine (Lys), and methionine (Met) in the diet of Nile tilapia Oreochromis niloticus fry. A control diet and four waste-amended formulations were administered to O. niloticus fry (initial weight 0.01 g; length 8.0 mm) for 84 days. The diets were designated as D1 (Fishmeal (FM) only), D2 (35.77% FIW + Lys and Met substituted FM protein in the diet), D3 (45.69% FIW/SSW + Lys and Met substituted FM protein in the diet), D4 (41.94% SSW+ Lys and Met substituted FM protein in the diet) and D5 (33.71% FIW/SSW only substituted FM protein in the diet). Each formulation was composed of 35% crude protein and 9.8% lipid. D2, D3 and D4 were supplemented with lysine and methionine. Nile tilapia fry fed D3 had the highest (P < 0.05) growth, feed utilization and body composition than those fed with the other experimental diets. Feed utilization and growth performance were lowest for D4 fed fish. Highest and lowest body compositions were observed in fish fed D1 and D2 respectively. The results revealed that judicious supplementation of recycled food wastes with lysine and methionine can effectively reduce FM utilization in the practical diet of Nile tilapia fry.