Utilization of DDGS by Cattle

Distillers grains with solubles (DDGS), the major byproduct of ethanol production, is a good protein and energy feed for cattle. The DDGS can be fed wet or dried with animal performance usually similar when fed as wet or dried products; however, some research results favored the wet products. Cattle diets can contain DDGS as replacements for portions of both concentrates and forages, although DDGS usually replaces concentrate ingredients. Most DDGS is from corn although wheat, barley, sorghum and other grains can be used for ethanol and DDGS production. The composition of DDGS from other grains often reflects the composition of that grain minus its starch that was fermented to ethanol. Distillers grains from corn is usually >30% CP, is high in ruminally undegradable protein, and is very good energy source (NEL ~2.25 Mcal/kg of DM) for lactating cows, growing, and finishing cattle. The modest fat concentration (10% of DM) and the readily digestible fiber (39% NDF) contribute to the high energy in DDGS. Distillers solubles are often blended with distillers grains to provide DDGS, but the solubles can also be fed separately as "thin stillage" or as "condensed distillers solubles". Protein and energy values are similar for distillers grains with or without solubles but the phosphorus content is elevated when solubles are included. The recommended amount of DDGS for feeding lactating dairy cows is up to 20% of total ration dry matter; higher amounts as much as 40 to 50% of ration dry matter can be successfully fed as an energy source to finishing cattle. The fiber in DDGS, which often replaces high starch feeds, does not eliminate acidosis but minimizes its problems. Innovations in processing technology and fractionation of the distillers products will likely result in additional products for future use as livestock feeds.