ARS | Publication request: Exploring new forage options to address emerging dietary and environmental challenges in dairy forage systems: reducing excessive weight gain in dairy replacement heifers fed a corn-silage based diet

Submitted to: Forage Focus
Publication Type: Popular Publication
Publication Acceptance Date: August 6, 2012
Publication Date: August 30, 2012
Citation: Coblentz, W.K., Bertram, M.G., Hoffman, P.C., Esser, N.M., Jokela, W.E. 2012. Exploring new forage options to address emerging dietary and environmental challenges in dairy forage systems: reducing excessive weight gain in dairy replacement heifers fed a corn-silage based diet. Forage Focus. pp. 17-18.

Technical Abstract: Dairy and forage producers are always facing new challenges. One of these challenges is to find forages that meet the specific nutritional needs of livestock at different stages of growth or production. In an effort to provide new and improved forage options to meet these emerging challenges, the U.S. Dairy Forage Research Center takes a multidisciplinary, whole-farm system approach to research. Corn silage is very popular with dairy producers, but feeding excessive amounts of this feedstuff to replacement dairy heifers can be problematic. Specifically, corn silage is energy dense, and heifers consuming this forage can become over-conditioned. Agronomic plot studies were initiated to determine if eastern gamagrass, a native warm-season perennial, could survive winter conditions throughout central Wisconsin. Warm-season perennials typically exhibit high concentrations of fiber (60-80% NDF), and are considered generally to be low-energy forages. A 3-year trial verified that the concept of growing eastern gamagrass in central Wisconsin is viable. Furthermore, a 120-heifer feeding study confirmed that this forage was effective in diluting the energy density of corn silage/alfalfa haylage diets, as well as reducing voluntary intake. Acceptable weight gains were maintained when eastern gamagrass comprised 30% of the total diet. An added bonus was that eastern gamagrass was not sorted by dairy heifers, which is a common problem when straw is added to diets to dilute energy.