Distiller's Dried Grains with solubles in diets for Nile Tilapia

Abstract

The research aims to evaluate, through three studies, the inclusion of DDGS (distillers dried grains with solubles) produced from corn and grain sorghum in diets for Nile tilapia. Study I: nutritive value of DDGS for corn and sorghum determined in digestibility assay, through ADC (apparent digestibility) of dry matter, crude protein, amino acids, gross energy, ether extract and the minerals calcium and phosphorus . Study II: replacement of soybean meal protein by protein DDGS from corn and sorghum. Will be considered to include these substitutes protein through the productive performance of 216 fish (average weight 5.0 g). The treatments will consist of nine diets, with a control (without addition of DDGS), and the other in which the protein of soybean is replaced by 25, 50, 75 and 100% of the protein in corn and DDGS 25, 50, 75 and 100% of the protein sorghum DDGS. It will be further determined the hematological profile of the fish (before and after the heat stimulus), and morphometric analysis of histological structures intestine and the liver. This study will use the factorial 2 x 4 + 1 (two foods, four levels plus a control) with four replications for performance and eight for evaluation of heat stress. Study III: nine nutritive value of diets Study - II through digestibility trial, conducted simultaneously to Study II. This study will use a randomized design with nine treatments and five replications. The productive performance, as well as the apparent digestibility of diets III study will be submitted to analysis of variance and in case of differences (P <0.05) will be subjected to regression analysis and Scheffé test comparison averages. For haematological variables will be applied multivariate analysis of variance test complemented with Bonferroni multiple comparison (5% significance). (AU)