By-Product Feeds as Energy Sources For Ruminants

Attractive costs have increased interest in the utilization of by-product feeds as alternative sources of energy and protein for the ruminant animal. Many by-product feeds have nutrient characteristics that make them suitable additions to ruminant diets. These nutrient characteristics include one or more of the following: higher level of undegradable intake protein (UIP), effective fiber, and(or) high energy value. In addition to cost considerations, it is important that substitution with a by-product feed results in equal or improved animal performance. By-product feeds that have been found to be effective as forage fiber substitutes but also have value as energy sources in ruminant diets were chosen for this review. Feeds that are discussed include beet pulp, brewers grains, citrus pulp, corn gluten feed, whole cottonseed, distillers grains, soybean hulls, and wheat middlings. This review evaluates these feeds in regard to their nutrient composition, nutrient digestion, and ruminal fermentation, and their impact on animal performance.