TP 11: Protein value of DDGS in ruminants

Due to the globally rising demand and production of bioethanol also the use of by-products in animal nutrition increases, such as distillers grains, which in Germany are also known as DDGS (Distillers Dried Grains with Solubles). Variations in quality are a major cause of the previously restrained use of DDGS. Recent studies show that fiber fractions, starch, crude protein and lysine contents vary greatly between the different ethanol plants. It is therefore necessary to learn more about the digestibility and availability of individual nutrients in DDGS, especially depending on the process technology. This information was gained by a cross section collective of European bioethanol plants, first of all exemplarily for the protein value of DDGS in ruminant nutrition. The ruminal crude protein degradation, the proportion of crude protein not degraded in the rumen, respectively (undegradable protein, UDP) were determined by chemical fractionation of crude protein and the in vitro ammonia release in the Hohenheim Gas Test. Furthermore, an estimation of the digestibility of UDP in the small intestine was carried out by means of a three-stage in vitro procedure with a simulation of the conditions in the small intestine, which is also established in Bonn. The close methodological networking with subproject 9 allows for a final comprehensive assessment of the protein value of grain and distillers grain as by-product in ethanol production for ruminants.

Subproject leader

Prof. Dr. Karl-Heinz Südekum

University of Bonn