ARS | Publication request: Apparent digestible energy value of crude glycerol fed to pigs

Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: March 19, 2007
Publication Date: March 19, 2007
Citation: Lammers, P.J., Kerr, B.J., Weber, T.E., Dozier III, W.A., Kidd, M.T., Bregendahl, K., Honeyman, M.S. 2007. Apparent digestible energy value of crude glycerol fed to pigs [abstract]. Journal of Animal Science. 85(Suppl. 2):87.

Technical Abstract: The apparent digestible energy of crude glycerol, a co-product of biodiesel production, was determined in two studies conducted at the Iowa State University Swine Nutrition Research Farm, Ames, IA. In the first study, 24 barrows with an average body weight of 11.0 kg were fed 376 g/d of a basal corn-soy-whey diet combined with either 0, 19, 38, or 75 g/d of crude glycerol. In the second study, 24 gilts with an average body weight of 109.6 kg were fed 2.29 kg/d of a basal corn-soy diet combined with either 0, 115, 229, or 458 g/d of crude glycerol. Crude glycerol was obtained from AG Processing Inc., Sergeant Bluff, IA and contained 86.95% glycerol, 9.63% water, 3.13% sodium chloride, and 0.03% methanol. Dietary treatments for each study were equivalent of 0, 5, 10, or 20% glycerol addition to basal diets. Each diet was fed twice daily to 6 pigs in individual metabolism crates. Following a 10 d adjustment period, total collection of feces and urine occurred for 5 d. Feces and urine were separately collected following each meal and stored at 0 degrees C. Gross energy of crude glycerol, diets, urine, and feces from each pig were determined by adiabatic bomb calorimetry. Apparent digestible energy was calculated by subtracting the energy in feces from the gross energy of the diet fed. Crude glycerol contribution to apparent digestible energy of the diet was regressed against crude glycerol intake for each pig size using the REG procedure in SAS. In nursery pigs the apparent digestible energy of crude glycerol was 3386 kcal/kg. In market pigs the apparent digestible energy of crude glycerol was 3772 kcal/kg. Those values were not different (P = 0.02) from the gross energy of the crude glycerol examined. For the sample examined, the gross energy of crude glycerol was 3625 kcal/kg. Crude glycerol may be a valuable source of energy for growing pigs.