Soybean meal is a major protein source of gestation and lactating sow diets because of its high protein quality and amino acid profile. But the quality of soybean meal varies depending upon the origin of soybeans and processing technology.

It is well known that the U.S.-originated dehulled soybean meal has an excellent nutrient profile compared to other country-originated soybean meals and other plant protein sources (Swick, 1995; Swick, 1998). Because of the relatively good amino acid profile, it is usually used to balance the dietary amino acid levels with cereal grains and their by-products in swine feeds. According to the NOPA (National Oilseed Processors Association) specification, crude protein contents of soybean meal vary from 47.5 to 49.0% without soy hulls