Corn Coproducts for Cattle

Corn distillers grains (CDG) and corn gluten feed (CGF) are the major corn coproducts fed to cattle. Both CDG and CGF can be fed wet or dried with animal performance usually similar when fed wet or dried products; however, some research results favored the wet products. Cattle diets can contain CDG or CGF as replacements for portions of both concentrates and forages. Distillers grains is a very good protein (>30% CP) source which is high in ruminally undegradable protein, and is very good energy (NEL ~2.25 Mcal/kg of DM) source 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 CDG. Distillers solubles are often blended with CDG to provide CDG plus solubles, but the solubles can also be fed separately as "thin stillage" or as "condensed corn distillers solubles". Protein and energy values are similar for CDG with or without solubles but the phosphorus content is elevated when solubles are included. The recommended amount of CDG 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. Corn gluten feed is a medium protein (24% CP), medium energy (~1.73 Mcal NEL/kg of DM) feed that also contains an abundance of digestible fiber (35% NDF). While CGF can be fed at higher amounts than one usually feeds CDG, optimal production and feed efficiency of lactating cows occurred with 18 to 27% of ration DM as CGF. Larger amounts, replacing nearly all of the concentrates and forages, were successfully fed to finishing cattle. The fiber in CDG and CGF, which often replaces high starch feeds, does not eliminate acidosis but minimizes its problems. Corn coproducts such as corn gluten meal (65% CP) and other modified products from dry and wet milling plants are additional items available as cattle feeds. Innovations in processing technology will likely result in additional products for future use as livestock feeds.