Hernández

Increasing levels of phytase in corn-soybean meal diets increases the standardized total tract digestibility of Ca in soybean meal when fed to growing pigs

Calcium (Ca) is an essential macro mineral required for growth, bone development and remodeling, enzyme activity, cellular signaling, and metabolic regulation in swine (González-Vega and Stein, 2014). The concentration of Ca in diets and ingredients is a key feature because excess Ca decreases the digestibility of P and other nutrients and decreases feed intake and growth performance (Stein et al., 2011; Merriman et al., 2017; Lagos et al., 2019). Ideally, the requirement for Ca should be expressed as standardized total tract digestible (STTD) Ca instead of total Ca (NRC, 2012), which necessitates the generation of values for Ca digestibility in feed ingredients (Lautrou et al., 2020; Lee and Kong, 2022; Lee et al., 2023a). In plant feed ingredients, Ca concentration is low compared with inorganic sources; however, Ca in soybean meal (SBM) ranges from 0.25% to 0.75% (Sotak-Pepper et al., 2016; Lee et al., 2023a). Because SBM sometimes is included at high proportions in swine diets, Ca analysis of SBM is important to supplement diets with adequate quantities of additional Ca to meet requirements without including excess Ca in diets.

Keywords: 
Calcium, microbial phytase, Phosphorus, Soybean meal
Authors: 
Jaramillo, Hernández, Lee, and Stein
Publication Type: 
Research Reports

Inclusion of microbial phytase in diets for growing pigs

Jaramillo, B. M., A. V. Hernandez, S. A Lee, M. Cristobal, and H. H. Stein. 2026. Inclusion of microbial phytase in diets for growing pigs. National Hog Farmer. On-line edition. April 30, 2026. Link to full text.

Keywords: 
microbial phytase, Growing pigs, Soybean meal
Authors: 
Jaramillo, Hernández, Lee, Cristobal, Stein
Publication Type: 
Extension Reports and other non-refereed publications

Effects of graded levels of phytase on apparent total tract digestibility of energy and concentrations of digestible and metabolizable energy in soybean meal

Soybean meal (SBM) is commonly used as a source of amino acids in swine diets because of its high protein content (Kudelka et al., 2021).  In addition, SBM contributes with energy and phosphorus (P). However, high portion of the P in SBM is bound to phytate, which is indigestible by pigs. Therefore, microbial phytase enzyme is supplemented in swine diets. The impact of phytase on the digestibility of P is well documented, however some experiments on digestibility in corn–SBM diets has been reported energy increase if microbial phytase was used (Liao et al., 2005; Arredondo et al., 2019; Lala et al., 2020; Espinosa et al., 2022), but, not in others (She et al., 2018; Mesina et al., 2019; Lamp and Moritz, 2022). There is, however, a lack of information about the impact of microbial phytase on the digestibility of energy in SBM. It is also not known if a possible effect of microbial phytase on energy digestibility in SBM is consistent among different sources of SBM.

Keywords: 
Calcium, Digestible energy, Metabolizable energy, microbial phytase, Phosphorus, Soybean meal
Authors: 
Jaramillo, Hernández, Lee, Stein
Publication Type: 
Research Reports