Summary and Implications
Pig diets in Iowa have historically been formulated using corn and soybean meal and the physical characteristics of that type of diet are well known. Virtually all feed storage, handling, and delivery systems found in Iowa are designed considering corn-soybean meal diets. Bio-fuel co-products are increasingly being included in pig diets. The bulk density of bio-fuel co-products is not well known. The purpose of this study was to determine the bulk density of 12 individual co-products, 12 grains, oilseeds, and other pig diet ingredients, and 11 mixed pig diets using established measuring apparatus and procedures. An alternative apparatus was designed and evaluated for measuring bulk density of pig diets, grains, oilseeds, and bio-fuel co-products.
Diet formulation affects bulk density with most diets examined differing in bulk density from ground corn. All co-products examined have a bulk density less than whole corn or ground corn. Incorporating co-products into pig diets will result in a more bulky feed. The precise relationship between co-product inclusion and the bulk density of the final diet remain to be determined. In general, adding co-products from bio-fuel production to swine diets results in reduced bulk density. Bulk density measurements are affected by measuring device used, but the differences are consistent. For the fabricated device described in this report, a correction factor of 66-67% may be appropriate. Calibrating a fabricated device with a USDA tester is critical for accurate bulk density measures.
Iowa State University
Letsche, Nicholas; Lammers, Peter J.; and Honeyman, Mark S.
"Bulk Density of Bio-Fuel Byproducts ,"
Animal Industry Report:
AS 655, ASL 2459.
Available at: http://lib.dr.iastate.edu/ans_air/vol655/iss1/81