The global swine industry adopted early-weaning practices a generation ago. However, early weaned piglets have been plagued by poor growth performance, known as the “post-weaning lag.” One cause of this is the piglets’ hypersensitivity to soy protein – specifically glycinin and β-conglycinin, which make up about 40% and 30% of the total protein found in soybean meal (SBM). These proteins have been found to be allergenic to the intestinal lumen, leading to biological responses like inflammation and minimized nutrient absorption capacity. Unlike other anti-nutritional factors in SBM, glycinin and β-conglycinin are not neutralized by thermal treatment experienced in SBM processing. This leads producers to utilize more digestible sources of protein. However, this comes at a cost, as they are much more expensive than SBM. Yet, this may not fix the problem, as diets will still have some level of SBM inclusion which can still generate allergic reactions in the gut.
Protease is a protein-degrading feed enzyme which increases the amino acid digestibility of protein substrates. In the case of SBM, these substrates include glycinin and β-conglycinin. Studies conducted by Novus International investigated the in vitro ability of CIBENZA® DP100 protease feed enzyme to hydrolyze soybean glycinin and β-conglycinin and then evaluated the in vivo effects of protease on performance, intestinal morphology, and inflammatory response of nursery piglets fed corn-soybean diets with different crude protein concentrations. Results of the studies are noted in the figures below.
In conclusion, the studies indicate that the protease can hydrolyze glycinin and β-conglycinin as observed by in vitro and in vivo trials. The hydrolysis of these antigenic proteins from soybean decreases the allergic reaction in the gut, thereby improving gut health, allowing piglets to grow faster and more efficiently, and also giving the flexibility for producers to include higher levels of SBM in nursery piglet diets which reduces feed cost.