This symposium provides new information on the unique value of soybean meal (SBM) for swine nutrition and health. This is the result of a three year study by a United Soybean Board (USB) committee of industry scientists. This paper describes four new concepts that emerged from their study of private sector research. These experiments tended to have no comparable counterparts in the literature. The most relevant experiments were published to advance our understanding of SBM energetic value (academic, commercial environment), its importance for maximum expression of growth and feed efficiency (FCE) and SBM’s ability to mitigate the growth impairing effect of respiratory disease. Private sector research also showed that extreme replacement of dietary SBM was the primary cause of summer carcass weight reduction. The process of taking this research public involved a series of reviews (committee, peer), followed by science editor review, and finally scrutiny by the two series editors. Ten papers were published in a format that required scientific rigor, translational discussion of new concepts and application. These appear in the symposium publication (ed. J. Garrett, D. Holzgraefe). The studies were not funded by USB or associated state organizations, however, they stimulated significant USB funding of research by better informed academic and private sector scientists. Knowledge advancement in SBM value fit 4 distinct categories: (I) Energetic value. SBM net energy (NE) was corrected to be 0.82 to 0.83 x corn NE (NRC, 2012), based on two private sector estimates on DM equivalent basis (Papers 1, 2), which agrees with a subsequent USB-funded calorimetry estimate (Lee et al., 2022). In the commercial environment, realized energetic value of SBM exceeded NE estimates (+30%). This was defined as productive energy, which encompassed but does not conflict with classic NE (Papers 1, 2). (II) SBM depletion in growing pig diets impairs growth and FCE in a dose-dependent manner. This was not resolved by restoring essential and non-essential amino acid content (Papers 5, 7). In addition, maximum growth and FCE could not be expressed in the commercial environment without a minimum SBM level for each growth phase (Papers 6, 10). (III) SBM mitigation of respiratory disease suppression of growth and FCE. The degree of recovery is SBM level dependent (Paper 3). (IV) Extreme SBM removal combined with DDGS levels exceeding 10% was determined as the primary cause of reduced carcass weight in summer harvested pigs (Papers 8, 10). An important hypothesis emerged from this diversity of studies. The uniqueness of SBM for growing pigs in the commercial environment (+ clinical signs of disease) is proposed to result from the abundance of functional compounds in SBM that serve complementary functions that enable more efficient nutrient use for growth (Papers 2, 3, 4, 10).

View the presentation of this abstract here and the interview with Drs. Boyd and Gaines by The Pig Site here.

Boyd, R. and A. Gaines. 2026. Four Pillars of Soybean Meal’s Unique Value to Swine Nutrition and Health. ASAS Midwest Section Meeting. Abstract 175. https://doi.org/10.1093/jas/skag107.215