Compared to solvent-extracted soybean meal (SBM), extruded full-fat soybeans (FFSB) provide greater energy due to their higher oil content, while expeller soybean cake offers a moderate improvement in energy relative to SBM. Issues feeding pigs high levels of FFSB include increased antinutritional factors and altered dietary fatty acid composition, which could antagonize growth and alter carcass iodine value and meat quality. Compared to conventional soybeans, feeding high oleic acid soybeans (HO) may lower dietary polyunsaturated fat content and improve pig growth performance. The objective of this study was to evaluate the effect of feeding conventional or HO extruded whole soybeans on grow-finish pig performance and carcass characteristics. A total of 1260 pigs (27.8±1.11 kg BW; PIC 800 x1050) were weighed and randomly allotted by sex across 60 mixed-sex pens (21 pigs/pen). Pens were blocked by location in the barn and randomly assigned, within block, to one of four dietary treatments (15 pens/trt): 1) Conventional solvent-extracted SBM (CON), 2) Conventional FFSB (CFFSB), 3) High oleic acid FFSB (HOFFSB), and 4) High oleic acid soybean expeller cake (HOEC). Diets were fed in five phases (~23-41, 42-63, 64-86, 87-109, and 110-133 kg BW) and were formulated to have similar SID Lys and SID Lys:ME. Pen BW and feed disappearance were collected at the start and end of each phase to calculate ADG, ADFI, and G:F. Pigs were marketed in multiple cuts at a target live BW of ~130 kg. At a commercial harvesting facility, carcass weight, backfat depth, and loin depth were collected per pig, and carcass yield and fat-free lean were calculated. Additionally, carcass fat samples were collected for fatty acid analysis. All data were analyzed according to a randomized complete block design, with treatment and block included as fixed effects in the models. Pen was the experimental unit. Pen average pig BW and mortality and removals did not differ between treatments (P > 0.10). Overall, CON, CFFSB, HOFFSB, and HOEC ADG were not different (0.87, 0.89, 0.89 and 0.88 kg/d, respectively; P = 0.491). However, ADFI was higher in CON, compared to HOEC, CFFSB, and HOFFSB (2.37, 2.25, 2.16 and 2.17 kg/d, respectively; P < 0.001). Consequently, CFFSB and HOFFSB improved overall G:F compared to CON (111%) and HOEC (105%) treatments (P < 0.001). Carcass weight and loin depth did not differ across treatments. Feeding CFFSB or HOFFSB increased backfat by 8% compared to CON, with HOEC being intermediate (P = 0.004). Feeding CFFSB resulted in marginally reduced fat-free lean percent compared to CON and HOEC, while HOFFSB was intermediate. In conclusion, CFFSB and HOFFSB improved feed efficiency and increased backfat, with no impact on growth compared to CON. Furthermore, HOEC reduced pig ADFI and improved feed efficiency compared to CON.

Lampe, K., N. Gabler, T. Crome, G. Gourley, L. Smith, E. Bruder, L. Greiner, D. Rosero, D. Jones and D. Humphrey. 2026. Evaluation of Conventional and High Oleic Soybeans on Grow-finish Pig Performance. ASAS Midwest Section Meeting. Abstract 167. https://doi.org/10.1093/jas/skag107.156