Extracts of green biomass as source of protein for pigs

The world-wide increasing demand for protein has lead to intensive search for sustainable alternative protein sources for monogastrics. Protein extracted from grass and forage legumes have the potential to become such source. However, the nutritional quality may depend on plant source, harvest- and processing conditions. Two studies with ileal-cannulated pigs fed concentrates with crude protein (CP) contents of 33-38 % of DM separated from perennial ryegrass (PRG), red clover (RC), and lucerne (LU) had standardized ileal digestibilities of indispensable amino acids of 62-81, except Cys which ranged 13-37 %; lower than of reference soybean meal (SBM). Higher CP content of the concentrates by improved harvest and processing technology may increase the nutritional quality. Such optimization is required for green biomass to be both environmentally and economically competitive as feed protein.