Improving nutrient availability of defatted rice bran using different phytase sources applied to grass carp
Edi F Ries1, Cristiano C Ferreira2, Fernanda R Goulart3
1Universidade Estadual de Campinas, Departamento de Ciência de Alimentos, Faculdade de Engenharia de Alimentos, Rua Monteiro Lobato, 80, Cidade Universitária, Barão Geraldo, 13083-862 Campinas, SP, Brazil.
Abstract:
In the present study, we evaluated the effects of the hydrolysis of phytate of defatted rice bran (DRB) by a pretreatment with non-commercial phytase produced by Saccharomyces cerevisiae (DRB-PS) compared to the application of Natuphos® (commercial phytase produced by the BASF Company) (DRB-PN) in diets for grass carp, Ctenopharyngodon idella. Fish (57.55 ± 0.4 g) fed one of the experimental diets in triplicates for 35 days. Effects of the phytase used on blood parameters, intestinal proteases and hepatic glucose were not observed (p > 0.05). Similarly, no differences were found for serum phosphorus (P). However, were found higher levels of calcium (9 and 5.25%) in the control treatment in relation to DRB-PS and DRB-PN respectively, besides higher calcium-phosphorus ratio was found in this treatment. For the fish carcass composition was not statistically different (p > 0.05) except total lipids, which showed its highest content in fish fed on the DRB-PN diet (p < 0.05). The obtained results suggested that the use of the phytase, irrespective to its source may eliminate the use of traditional P sources in fish diets.
