Evaluation of growth, nutrient digestibility, and hematological parameters of tilapia, Oreochromis niloticus, fed diets containing different levels of high protein distiller's dried grain with yeast in it as replacement for corn protein concentrate

Abstract

Two novel technologically advanced high protein distiller dried grains with yeast in it (HP50Y & HP40Y) were evaluated for juvenile tilapia. This experiment assessed the nutritional potential of using high protein (40 and 50%) distillers dried grain to replace corn protein concentrate (CPC) in formulation of tilapia diets for more sustainable development of aquaculture. A 10-weeks growth trial was conducted, using nine diets formulated to contain 32% protein and 6% lipid. Each protein was included at levels (0, 5, 10, 15 and 20%) replacing CPC on protein basis. Juvenile tilapia (mean initial weight 5.23 ± 0.20 g) were evenly distributed in thirty-six, 75-L aquaria working as a recirculating system and fed twice daily to apparent satiation throughout the study. Tilapia exhibited no significant (p > 0.05) differences in growth, FCR, survival, whole-body proximate composition, mineral composition, and hematological parameters when fed HP50Y and HP40Y supplemented diets compared to the control diet. Digestibility coefficients for the test ingredients were determined in tilapia for dry matter, energy, crude protein, individual and total amino acids using 1% titanium oxide as the inert marker with 70:30 replacement strategies. All the values were found in acceptable range for the distiller grains when compared to literature. Results from this study revealed that HP50Y and HP40Y both are good alternative protein sources and can be used up to 20% inclusion level in the diets of tilapia.