Effect of over processed fish meal in diet formulation for broilers according to digestible amino acid basis | Efecto de la incorporación de harina de pescado con distinto grado de cocción a dietas para pollos de engorda formuladas a un perfil de aminoácidos digestibles

anglais. Digestible amino acid (DAA) basis formulation allows including low quality protein constituents in diets. In the first test, commercial fish meal (FM) was over processed by autoclaving at 121 °C and 1 kg cm-1 for 0, 30, 60 and 90 min. True digestibility (TD) of amino acids (AA) and protein digestibility (PD) in FM were determined in vivo using a precision-feeding assay with roosters. A second in vitro test was carried out to determine if, either filtration pepsin (FP) or ninhydrine pepsin (NP) assays showed potential for predicting in vivo PD on FM. In a third test, two days old mixed chicks were distributed in eight treatments with six replicates of 20 chicks each in a randomized factorial 2 x 4 design. One factor assessed was over processed FM and total amino acid basis (TAA) or DAA formulation. Results show that true digestibility of analyzed AA and PD in FM decreased (P0.05) between FM and formulation methods. There was a significant (P

espagnol; castillan. Formular a aminoácidos digestibles (AAD) permite incluir en la dieta ingredientes con menor calidad proteica. Se calentó (C) harina de pescado (HP) durante 0, 30, 60 y 90 min (autoclave a 121 °C y 1 kg/cm2 de presión), determinando in vivo su digestibilidad verdadera de aminoácidos y proteí­na (DP). Se comparó la DP in vivo vs dos técnicas in vitro: pepsina por filtración (PF) y pepsina con ninhidrina (PN). En otro ensayo, pollitos mixtos se asignaron a uno de los siguientes tratamientos con seis repeticiones de 20 pollos cada uno, en un arreglo factorial 2 x 4, con un diseÅ„,o completamente al azar. Un factor fue, el tiempo de C de la HP, el otro, formular dietas con aminoácidos totales (AAT) o AAD. El calentamiento redujo linealmente (P