Impact of Soybean Meal Energy on Lysine and Phosphorus for PIC Growing Pigs

Soybean meal (SBM) is the major plant-protein source in diets for swine world-wide. It is anticipated that the increased demand of soybean oil for renewable fuels will result into an increase in the US SBM production. In addition to providing protein and amino acids, the nutritional value of SBM is also impacted by the energy it provides.

In current ingredient databases, solvent extracted SBM is assumed to provide less than 80% of net energy (NE) value of corn for growing pigs (NRC 2012; Brazilian Requirement Tables 2024; CVB, INRA, FEDNA). However, recent research is indicating that SBM is providing more energy than referenced in book values (Carrender et al.,2019; Cemin et al., 2020; Lee et al., 2022; Boyd and Gaines, 2023; Guo et al., 2024). It is important to consider that differences among genetic varieties of soybeans, growing conditions, and soybean processing may all affect the nutritional value of SBM produced in different places.

PIC standardized ileal digestible lysine (SID Lys), standardized total tract digestible phosphorus (STTD P), and available phosphorus (Av. P) to NE ratio requirement estimates have been developed assuming a SBM to corn NE value of 78%. For nutritionists that adopted the NE system in diet formulation and may value SBM NE above 78%, these recommendations have been updated to be applicable for SBM to corn NE values ranging from 78 to 100%.

The PIC Nutrient Specification Tables (Metric, Metric-Joules, or Imperial) can be assessed to obtain examples of the lysine and phosphorus to calorie ratio recommendations for SBM to corn NE ratios of 78%, 90%, and 100%.

The PIC Recommendations for Wean to-Finish Pigs tool can be utilized to access tailored recommended nutrient to energy ratios to maximize performance of different genetic lines, gender, body weight, and SBM to corn NE ratio.

See below for a short video explaining the development of the equations to determine Lys to NE ratio and P to NE ratio at different SBM to Corn NE ratios. Additionally, you can find a list of references on this topic here. More detailed information can also be found on Sections C, D, and R of the PIC Nutrition and Feeding Guidelines (https://www.pic.com/resource-category/nutrition/).

Be aware that if the SBM NE is overestimated, the percentage of dietary SID Lys may be underestimated. PIC has found an increased risk of abnormal behavior when pigs are fed below 85% of their biological SID Lys requirement before achieving their maximum protein deposition. This risk can also occur at the beginning of a body weight range if the range is too wide.