Determine prediction equations of the total and standardized ileal digestible amino acids of fish meal from its chemical characteristic in broilers

This experiment was conducted to determine total amino acid (AA) content and standardized ileal digestible (SID) amino acid content of 6 different origins of fish meal (FM) and subsequently determine equations that estimate total and SID amino acid contents from chemical composition as well as SID amino acid contents from its total AA. In order to conduct this study, a total of 210 one-day-old male broiler chicks were randomly assigned to 7 dietary treatments consisting of 6 semi-purified diets containing each of FM as the only source of dietary protein (200 mg of crude protein/g diet) and one nitrogen-free diet in order to determine ileal endogenous amino acids (IEAA) flow. Birds were allowed ad libitum access to a corn-soybean meal starter diet until ten days, a grower diet from 11 to 23 days, and then experimental diets from 24 to 28 days of age. The total content of Lys and Met among the various samples significantly differed from 1.52 to 2 and 0.59 to 0.77%, respectively (P < 0.05). This difference was observed among the other total and SID amino acids. In this study the accuracy and precision of the models were tested by the adjusted coefficient of determination (R2) value, P-value regression coefficients, and standard error of prediction (SEP). The SEP of the developed regression equations for the predicting SID amino acids of FM were from 0.009 (for Met) to 0.056 (for Arg).