Effect of soybean variety and processing on growth performance of young pigs

The soybean is known as an excellent source of protein when formulating diets for swine. However, this potential can be achieved only if certain quantity of heat is applied. Osborne and Mendel (1917) were the first to report that raw soybeans had a growth-depressing effect in rats. Generally, these heat labile factors are protease inhibitors, lectins, goigotrens and antivitamins. The most common way of eliminating these factors is by heating or “toasting” the soybeans in a processing plant, being sure that temperature, duration of the heating, particle size and moisture are controlled. Another way to inactivate these factors is by dry extrusion (without steam).