Use of distillers' dried grains with solubles (DDGS) in the diet of broiler chicken: a review

Abstract

A large amount of cereals, particularly maize, is being channelled into ethanol production, for inclusion in bio-fuels. A major by-product of this process is distillers' dried grains with solubles (DDGS). The volume of production of DDGS in the USA is quite high. It is estimated that around 38 million tons of DDGS are currently produced per year by the USA alone. However, its composition is variable due to a number of factors, including agronomic practices and processing techniques. DDGS can also vary in physical appearance and chemical composition, depending on the cereal grain used and the processing and drying techniques, but generally have a higher concentration of amino acids and other components than the original feedstock. Historically, DDGS have been used primarily in ruminant diets. While that is still true today, DDGS are finding their way into poultry and swine diets at an ever-increasing rate. The inclusion rate of DDGS in broiler diets is at a level of 10-15% during the whole broiler production cycle, and 20-30% in swine diets. It is possible to increase the digestibility of DDGS through supplementation with exogenous enzymes. Enzyme-mediated improvement of diet digestibility has a direct effect on the amount of feed required to reduce the nutrient requirement and manure output. For example, improvement of digestibility from 85 to 90% results in a 5% reduction in the amount of feed required and 33% reduction in faecal output. Distiller's DGS is a good source of energy and protein. It may be necessary to supplement the diets with microbial enzymes, to sustain production at the current levels. This review will present findings on current use of DDGS around the world, including avenues for improving the nutritive value of poultry diets that contain DDGS.