Distillers grains (DGS) have been the primary source of supplemental protein in cattle diets for more than twenty years. As ethanol production ramped up in the Corn Belt, DGS became a widely available and favorably priced alternative to other protein sources and quickly took the position as the default protein source.

At one time, DGS were priced at a significant discount to corn, now those feedstuffs are usually priced at nearly the same cost per unit of dry matter. The cattle being fed have also changed. Cattle today grow faster, have improved marbling, and are marketed at heavier weights compared to when DGS were first studied. For those reasons, the SDSU Feedlot Research group has been re-examining whether soy protein fits into modern cattle feeding diets.

Heat-treated soybeans offer attributes that could enhance cattle growth. Applying heat to a feed can alter structures, resulting in reduced degradation in the rumen and potentially greater absorption of intact proteins in the small intestine. Soy-based protein contains more lysine compared to corn, so increasing the supply of this essential amino acid could increase cattle growth. In addition, including soybeans in cattle diets increases energy density because of the oil in soybeans. Increased energy concentration from fat results in greater feed efficiency.

Read more about SDSU research on soybeans in cattle diets here.

This research was made possible by support from the SD Soybean Research & Promotion Council.