<b>Phytase as feeding for Nile tilapia (<em>Oreochromis niloticus</em>), during sex reversion period</b> - DOI: 10.4025/actascianimsci.v26i3.1778

Abstract

This work was carried out to examine the influence of dietary levels of phytase on Nile tilapia (Oreochromis niloticus) performance during the sex reversion period. Were used 1,000 fries of Nile tilápia with initial weight 0.02 ± 0.002g, fed with diets containing 0; 500; 1000; 2000 and 4000 phytase units (PU)/kg of diet 31 days. The reference diet provided 3,143 kcal of digestible energy/kg, 30% of crude protein and 0,85 and 0,35% of total and disponible phosphorus (P), respectively. No effects (P>0.05) were observed of phytase inclusion on weight gain and survival rate. Dietary phytase levels increase linearly (P<0.05) the calcium retention in the carcass. There was observed quadratic effect (P<0.05) of dietary phytase supplementation on P retention in the carcass, estimated the values of 1,990 PU/kg for the highest value for this variable. The results of this work indicate that a dietary level of 1,990 of PU provide maximal P retention in the carcass of Nile tilapia, during sex reversal period.