ATTRA Question of the Week

B.B.
Massachusetts

Answer: Soybean meal is a very common protein source and is widely used as a supplemental livestock feed. Substances that inhibit trypsin (a protein-digesting enzyme) are found in soybeans. Soybeans used in feed should first be roasted or heated because the trypsin inhibitors are destroyed by moist heat. Typically the heat occurring during processing is enough to denature the trypsin inhibitors.

Several articles that discuss the various ways of processing soybeans and soybean meal are listed below, as well as a couple of articles that discuss using soybean meal as a livestock feed.

Resources:

Jurgens, M. 2002. Animal Feeding and Nutrition. Kendall/Hunt Publishing. p. 199-200.

Soybean Processing. www.soymeal.org/pdf/processing3.pdf. (PDF / 163K)

Ensminger, M., Oldfield, J., & Heinemann, W. 1990. Feeds & Nutrition Digest. The Ensminger Publishing Company. p. 208-209.

Lin, C. & Kung, L. n.d. Heat Treated Soybeans and Soybean Meal in Ruminant Nutrition. www.asa-europe.org/pdf/heattreated.pdf (PDF / 54K)

Vohra, P. & Kratzer, F. n.d. Evaluation of Soybean Meal Determines Adequacy of Heat Treatment. www.asa-europe.org/pdf/evaluation.pdf (PDF / 62K)

Demjanec, B., et al. 1995. Effect of Roasting on Site and Extent of Digestion of Soybean Meal by Sheep. Journal of Animal Science. Vol. 78. p. 824-834. http://jas.fass.org/cgi/reprint/73/3/824.pdf (PDF / 1.1M)

Stanton, T. & LeValley, S. n.d. Feed Composition for Cattle and Sheep. www.ext.colostate.edu/pubs/livestk/01615.html

Schwulst, F. 1988. Raw Soybeans in the Diets of Sheep. www.oznet.ksu.edu/library/lvstk2/SRL96.pdf (PDF / 25K)

Schoenian, S. n.d. An Introduction to Feeding Small Ruminants. www.sheepandgoat.com/articles/feedingsmallruminants.html