Composition of Distillers Dried Grains with Solubles

Another hot topic at the recent animal and dairy science meetings was the growing supply of distillers dried grains with solubles (DDGS). The growth of the ethanol industry has resulted in large supplies of DDGS that are competing with soybean meal in livestock and poultry feed formulations. A recent paper by researchers at the University of Georgia has developed a lot of information on composition of DDGS that impacts its use. The researchers obtained seventeen commercial DDGS lots from six different plants in the Midwestern U.S. between 2002 and 2004. Each sample was analyzed for proximate composition and metabolizable energy; eight samples were analyzed for total amino acid content and digestible amino acids using a precision-fed rooster assay. The results are shown in the following table.

Table: Composition of DDGS (*)


(*) Proximate composition on 17 samples and data expressed on 86% dry matter basis; amino acids data based on 8 samples and data expressed on an as-fed-basis.
(**) TME(n) determined with the precision-fed rooster assay with 10 Single Comb White Leghorn roosters per sample.
(***) Determined with 5 cecectomized Single Comb White Leghorn roosters per sample.

The authors reported that these values agree with other values in the literature and the average concentrations and digestibilities of amino acids were only slightly lower than that of corn. They concluded that relative large variations in metabolizable energy and amino acid digestibilities among the commercial DDGS samples are a problem and that poultry nutritionists should conduct confirmatory analyses when using DDGS from new suppliers. Variability of nutrients in feed ingredients is a major problem when formulating least-cost rations with narrow margins of safety in nutrient specifications.

Batal, A.B. and N.M. Dale. 2006. True metabolizable energy and amino acid digestibility of distillers dried grains with solubles. J. Applied Poultry Res. 15: 89-93.