Combined Effects of Citric Acid and Phytase Supplementation on Growth Performance, Nutrient Digestibility and Body Composition of Labeo rohita Fingerlings

Abstract

Aquaculturists have been concentrating their efforts to design aquafeeds using agro by-products to reduce feed costs. However, the presence of a wide variety of antinutritional factors (ANFs) in plant materials is one of the major obstacles. For this purpose, a 2x2 factorial experiment was established to evaluate the suitability of canola meal with citric acid (CA) and phytase (PHY) supplementation for growth performance, nutrient digestibility and body composition of Labeo rohita fingerlings. Five isocaloric and isonitrogenous diets; D1 (control; without CA and PHY), D2 (CA 15 g/kg+PHY 1000 FTU/kg), D3 (CA 30 g/kg+PHY 1000 FTU/kg), D4 (CA 15 g/kg+PHY 2000 FTU/kg) and D5 (CA 30 g/kg+PHY 2000 FTU/kg) were fed to fish (mean initial weight 7.61±0.31 g) in triplicates for 90-days. The growth performance was significantly increased while feed conversion ratio was decreased with D3 compared to control and other CA and PHY supplemented groups (P<0.05). Furthermore, higher digestibility (%) of nutrients (dry matter, crude protein and ash) and improved whole-body composition was also exhibited by fish fed with D3 (P<0.05). Hence, the above results elucidate that supplementation of 30 g/kg CA with 1000 FTU/kg PHY could be a useful approach for improved growth performance, nutrients digestibility and body composition of L. rohita.