US soybean seed protein concentrations—Current status, challenges, and some potential crop management solutions

Soybean [Glycine max (L.) Merr.] is the major source of protein for livestock and poultry feed in many countries including the United States. The United States is the second largest exporter of the soybean in the world. Although soybean yield in the United States has gradually increased over the past few decades, a consistent decline in seed protein concentration during the same period has occurred. As a result, soybean meal produced from some US seeds fails to meet the high-quality animal feed standards. Due to this trend, there is an urgent need to improve seed protein concentration to make US soybean competitive in the global feed market. This review article discusses the status of declining soybean seed protein concentration trend in the United States, its effect on soybean meal and animal feed quality and some potential solutions to promote soybean nutritional quality.