Amino Acid Variation in Distillers Dried Grains with Solubles

An interesting paper was published in Feed Management on using regression analysis or near-infrared reflectance spectroscopy (NIRS) to analyze amino acid levels in feed ingredients.  The research group developed regression equations for estimating lysine, methionine and threonine levels obtained from 455 samples of distillers dried grains with solubles (DDGS) using classical wet chemical methods.  Plotting lysine, methionine and threonine concentration versus crude protein of DDGS samples obtained correlations coefficients of 0.49, 0.68 and 0.86, respectively.  The author stated that using regressions to predict amino acid values for DDGS are not accurate enough to be used in formulating feeds and could be costing producers in over-formulations costs or losses in animal performance.  The large variation in crude protein and amino acid levels in DDGS justifies analyses of individual shipments using traditional wet chemical methods or NIRS techniques.

Goodson, Jonathan.  2006.  Amino acid levels in feed ingredients: Regression or analysis?  Feed Management.  November/December issue, pages 14-17.