Dietary phytase in juvenile pacu (Piaractus mesopotamicus) diets

Abstract

This work was undertaken out to evaluate the effects of dietary phytase on pacu juvenile performance and mineral retention. One-hundred and sixty fish (16.42 ± 2 g) were fed diets containing 0; 500; 1,000 and 2,000 phytase units (PU)/kg of diet containing approximately 3,238 kcal of digestible energy, 30% of crude protein and 0.31% of available phosphorus. One-hundred and sixty fish were fed to apparent satiation for 60 days. No effects of the dietary phytase on survival, carcass humidity, crude protein and fat were observed. Increasing dietary phytase levels linearly increased weigh gain, carcass ash and bone ash, and a quadratic effect on feed conversion ratio, which the best values, were obtained using 433.33, 425, 1875 and 1833 PU/kg of diet respectively. It was concluded that the optimum phytase supplemental level in the diet of juvenile pacu is 433.33 PU/kg of diet.