Trypsin Inhibitor and Urease Activity of Soybean Meal Products from Different Countries and Impact of Trypsin Inhibitor on Ileal Amino Acid Digestibility in Pig
Juxing Chen, Karen J. Wedekind, Jeffery Escobar, M. Vázquez-Añón
Abstract
Abstract Trypsin inhibitor (TI) and urease activity (UA) are the most relevant quality aspects of soybean meal (SBM) for monogastric animals. This study’s objective was to determine the levels of TI and UA in SBM collected from feed mills in different countries, whether TI and UA are correlated since they are both heat‐labile, and impact of TI on pig ileal amino acid digestibility. TI was 1.20–8.37 mg g −1 with 36.4% samples <3 mg g −1 , UA was 0–0.311 ΔpH unit with 64.2% samples <0.05 ΔpH unit in 847 solvent‐extracted SBM samples. TI and UA results varied by countries and world areas. By country, mean TI was highest in Germany and lowest in Philippines, mean UA was highest in India and lowest in Philippines. By world areas, mean TI was highest in Latin America and lowest in North America, UA was highest in Asia and lowest in Latin America. TI and UA results vary in different soybean products, TI ranked as raw soybeans > expeller SBM > full‐fat‐extruded (FFE) SBM ≥ heat‐inactivated full‐fat (HIFF) SBM > solvent‐extracted SBM; UA ranked as raw soybeans > HIFF SBM > FFE SBM ≥ solvent‐extracted SBM ≥ expeller SBM. TI was not correlated with UA in 847 solvent‐extracted SBM, suggesting that UA may not be used as a surrogate indicator for TI. A diet contained 38% SBM with 8.78 mg g −1 TI significantly reduced apparent ileal digestibility of amino acids and crude protein by 13.3–26.0% and 23.3% points, respectively, in cannulated pigs compared to SBM with 2.51 mg g −1 TI.