Low Trypsin-Inhibition soybean demonstration
Soybeans (Glycine max) are an important source of protein in animal diets, fed as soybean meal. Raw soybeans contain trypsin inhibitor (TI), which reduces protein digestion, feed efficiency and limits on-farm feeding of raw, unroasted soybeans to pigs. Because the majority of the soybeans produced in the US are genetically engineered (GE), the soybean meal available for livestock feed is predominately derived from GE soybeans. No sources of non-GE soybean meal are available on the market today. Planting non-GE soybeans with low-trypsin inhibition could reduce the cost of animal feed and allow farmers to use a non-GE soybean source. Normally soybeans need to be roasted, oil extruded, and then returned to the farm as soybean meal before they are suitable to be fed to animals. New varieties of soybeans selected for low concentrations of trypsin inhibitor are being developed by eMerge Genetics, West Des Moines, IA. In 2011, a variety of low TI soybeans grown in North Central Iowa yielded similarly to other varieties from the same farm and had measurably lower levels of TI than commodity soybeans.