ENZYME COMPLEX ON DIGESTIBILITY OF ENERGY AND NUTRIENTS IN PRACTICAL DIETS FOR NILE TILAPIA, Oreochromis niloticus JUVENILES

Abstract

The present study was aimed to evaluate the effects of Allzyme SSF®, a multienzyme complex with pectinase, protease, phytase, β-glucanase, xylanase, cellulase, and amylase, on the apparent digestibility coefficients for Nile tilapia, Oreochromis niloticus. A total of 90 healthy, 100-day-old, all-male fish (150 ± 20 g) were randomly allotted into six-200-L digestibility aquaria at stocking density of 15 fish per aquarium. A typical commercial tilapia feed formulation containing 33.27% of crude protein (21.11% from animal protein source + 12.16% from plant protein source), and 20.18 MJ/kg of gross energy was used as basal diet. The dietary treatments assigned were: control diet (D1) without multienzyme supplementation, D2 and D3 supplemented with 0.0225% and with 0.045% of Allzyme SSF®, respectively. Chromic oxide at 0.1% was used as inert marker. Higher apparent digestibility coefficients of dry matter and gross energy were observed in fish fed diet D3 compared to those fed the control diet (P < 0.05). Fish fed diet D3 showed higher apparent digestibility coefficients of starch, ash and zinc compared to those observed in fish fed control and diet D2 (P < 0.05). Fish fed diet D2 and D3 demonstrated higher apparent digestibility coefficients of calcium and phosphorus than fish fed the control diet (P < 0.05). No effect of multienzyme complex supplementation on apparent digestibility coefficients of lipids was observed (P = 0.811). Dietary multienzyme complex supplementation in diet D3 improved apparent digestibility coefficients of lysine (P = 0.022), histidine (P = 0.001) compared to fish fed D1. Higher apparent digestibility coefficients of leucine, threonine, tryptophan and valine were observed in fish fed diet D2 and D3, compared to those fed the control diet (P < 0.05). Lower nitrogen and phosphorus excretions were observed in fish fed diets supplemented with the multienzyme complex compared to the control diet. In conclusion, a dietary supplementation of 0.045% of Allzyme SSF® may be used as useful tool to improve nutritive value of feeds and support the sustainability of Nile tilapia culture.