Effects of dietary protein substitution of fish meal with bioprocessed poultry by‐product meal on growth performances, nutrient utilization, whole‐body composition and haemato‐biochemical responses of GIFT tilapia reared in floating cages

Abstract

A 60-day feeding trial was conducted to examine the effects of replacing fish meal protein with poultry by-product meal (PBM) and bioprocessed poultry by-product meal (BPBM) on growth performance, nutrient utilization, whole-body chemical and amino acid composition and haemato-biochemical responses in GIFT tilapia reared in floating cages. Seven isonitrogenous (320 g/kg crude protein), isolipidic (50 g/kg crude lipid) and isoenergetic (17 MJ/kg) experimental diets were formulated by replacing 0%, 33.33%, 66.67% and 100% of fish meal protein with PBM and BPBM respectively and referred as Control, PBM 33.33, PBM 66.67, PBM 100, BPBM 33.33, BPBM 66.67 and BPBM 100. Triplicate groups of 30 GIFT tilapia juveniles with an average initial weight of 11.28 ± 0.14 g were fed with experimental diets daily thrice until apparent satiation (08:00, 12:00 and 16:00 h). Among PBM and BPBM dietary groups, significantly (p < 0.05) higher growth performance and nutrient utilization were observed in fish fed BPBM 66.67 group compared to other treatment diets including control diet. No significant difference (p > 0.05) was observed in survival rate of GIFT tilapia fed different levels of PBM and BPBM-incorporated diets. Moreover, dietary inclusion of PBM and BPBM did not (p > 0.05) affect the whole-body chemical and amino acid composition and haemato-biochemical responses in GIFT tilapia. It is concluded that PBM and BPBM can completely replace dietary fish meal protein in GIFT tilapia diets without any negative impact on growth performances, nutrient utilization and blood haemato-biochemical responses. However, significantly higher growth performances and nutrient utilization were obtained in fish fed BPBM 66.67 diet.