Written by: Dr. Jacquie Jacob, University of Kentucky
The cowpea (Vigna unguiculata) is an important grain legume in tropical and subtropical regions. Cowpeas are heat- and drought-tolerant crops. Cowpeas are suitable for use in poultry feeds, and their nutrient composition is similar to that of lupins and field peas, but not as good as soybeans or canola.
Cowpeas have an amino acid profile similar to that of soybeans. Cowpeas are characteristically low in sulfur-containing amino acids (methionine and cysteine) and high in lysine. Like other grain legumes, cowpeas contain anti-nutritional factors. Such anti-nutritional factors—including protease inhibitors, non-starch polysaccharides (NSP), pectins, and phenolic compounds—reduce protein quality and nutrient digestibility. The protease inhibitors impair the activity of pancreatic enzymes such as trypsin and chymotrypsin.