Factors associated with the utilization of distillers byproducts derived from the dry-milling process in finishing diets for feedlot cattle

The fuel ethanol industry is currently experiencing tremendous growth with production estimates in excess of 30 billion liters over the next decade. Byproducts from the production of fuel ethanol are distillers grains and condensed distillers solubles which are often mixed together to produce wet or dry distillers grains plus solubles. Past research has demonstrated that wet distillers grains plus solubles (WDGS) has a higher energy value relative to corn in finishing diets for feedlot cattle, which, along with an increasing supply, has made it an attractive feed ingredient. Six feeding trials and one economic analysis evaluated the use of distillers grains plus solubles in finishing diets. Feedlot cattle fed increasing dietary inclusions of WDGS demonstrated greatest feed efficiency at a 40% WDGS inclusion (DM basis). Wet distillers grains plus solubles returned more dollars per head than conventional high concentrate feeding. Dietary inclusions of WDGS that maximize return are between 30 and 40% of diet DM near the ethanol plant or up to 48 km from the plant while the economics favor dietary inclusions between 20 and 30% of diet DM between 48 and 161 km from the ethanol plant. Cattle fed dry distillers grains plus solubles (DDGS) supplemented with degradable intake protein (DIP) performed similar to cattle not supplemented with DIP. Cattle fed high-moisture corn based finishing diets with 30% WDGS had greater feed efficiencies than cattle fed corn processed by five other methods. Performance for cattle supplemented with corn oil were lower compared with cattle fed equal amounts of dietary fat provided from WDGS; however, cattle fed DDGS or tallow in finishing diets containing 20% wet corn gluten feed demonstrated similar finishing performance. Cattle fed WDGS demonstrated lower acetate: propionate ratios, greater fat digestibility, and more unsaturated fatty acids reaching the duodenum than cattle fed supplemental corn oil. These data demonstrate the effectiveness of distillers byproducts used in diets for feedlot cattle.