Editor’s note: The following is excerpted from an article written by J.W. Schroeder, dairy specialist at North Dakota State University. In his article, he acknowledged a presentation by Normand St-Pierre of Ohio State University and Joanne Knapp of Fox Hollow Consulting, “Economics of Making Nutritional Decisions with Volatile Feed Prices,” during the High Plains Dairy Conference in Albuquerque, N.M., in late March.
Byproduct feeds can be used to replace both forages and grain in dairy cattle diets. Several research articles have been published on the ability of byproducts, such as corn gluten feed, beet pulp and soy hulls, to replace forage. Alternatively, and more importantly in this era of ethanol euphoria, byproducts also can be used to replace grains. Byproducts are generally much lower in starch than grains, but contain significant quantities of other nonfiber carbohydrates (NFC), including sugars, organic acids, fructans, glucans and pectins.
These sources of NFC are generally very degradable in the rumen and can provide energy to both the rumen microbes and the cow. Several studies have shown no decrease in rumen microbial flow to the small intestine, total tract NFC and NDF digestibilities, dry-matter intake, and milk yield and milk components when byproduct feeds are substituted for corn grain in dairy rations. Starch contents of the diets ranged from 9.2 percent to 38.3 percent dry matter (DM), with corresponding NFC levels ranging from 27.2 percent to 50.7 percent of DM and NDF levels inversely ranging from 49.4 percent to 24.3 percent of DM. In all of these studies, forage NDF levels were maintained within or above current National Research Council recommendations for forage NDF. See Schroeder’s entire article. Also, see this research summary that he included as an attachment.