Soaring corn prices will increase the potential economic benefits from substituting alternative feed ingredients for corn in broiler rations.
Traditionally, corn has been the primary ingredient in broiler rations and has been counted on to provide much of the energy in the diet. At the same time that ethanol producers are increasing demand for corn – thus helping to drive up the price – they are offering livestock and poultry producers an ever increasing amount of distiller’s grains with solubles as an ingredient to substitute for corn.
Dr. Mark A. Giesemann, Dakota Gold Marketing, spoke on the subject of the ethanol industry and its by-products at the Pre-Show Nutrition Symposium of the Midwest Poultry Federation Convention. He said that since 1995 all new ethanol plants in the USA have been constructed to use a dry-grind ethanol process. Edible by-products of this process are corn condensed distiller’s solubles and distiller’s grains, which when combined and dried are called dried distiller’s grains with solubles (DDGS). Giesemann said that the ethanol industry in the USA produced over 10 million tons of DDGS in 2006.
Giesemann described the dry grind process for making ethanol and explained how DDGS differs from corn. “To begin the process, grain is ground and then mixed with water and cooked to gelatinize the starch. The starch is converted to glucose by enzymes and then into ethanol by yeast,” he said. What are left in the DDGS are the oil, protein and fiber portions of the corn kernel. For each 56 pound bushel of corn used to make ethanol around 17 pounds of DDGS are left over as a byproduct. DDGS generally has three times the protein and fiber of corn. Giesemann said that some ethanol producers are starting to use production methods that will allow them to extract the corn oil early in the process, and this will yield DDGS with even lower energy levels.
Because ethanol production processes vary from plant to plant and because a live organism, yeast, is involved, there is a lot of variability in the nutrient composition of DDGS from batch to batch within a plant and between plants. Variability is not a good thing when it comes to feed formulation. High variability means building in bigger safety factors which can mean sometimes over feeding and sometimes underfeeding certain nutrients.
Feeding trials with DDGS for poultry show that it can be incorporated into poultry rations at a rate of up to 15 percent of the diet without affecting feed conversions, Giesemann said. In the past, much of the DDGS produced in the USA has been used to feed cattle. Corn prices as high as $4 per bushel will provide an incentive for poultry companies to experiment with incorporating all sorts of alternative ingredients into their rations, and DDGS might be on the menu for your birds in the near future.
