The improvement of yield or oil content in soybean seeds, mainly through genetic modification, has often resulted in a decrease in protein concentration. However, a new genetic technology patented as Photoseed was used to develop a new variety of soybeans. By modifying genes involved in biosynthesis and storage of lipids, it was possible to increase the accumulation of lipid droplets and increase carbon capture. This resulted in soybeans that contain more oil, without negatively affecting crude protein concentration, compared with conventional soybeans. There is, however, no information about the nutritional value of the soybean meal produced from the Photoseed variety of soybeans. Therefore, the objective of this study was to test the hypothesis that nitrogen-corrected true metabolizable energy (TMEn), standardized amino acid (AA) digestibility, and apparent ileal P digestibility are not different in a soybean expeller (SBE) produced from a new variety of Photoseed soybeans compared with SBE produced from conventional soybeans.  

Lopez, Diego A., Su A. Lee, Hans H. Stein. 2022. Effects of microbial phytase on standardized total tract digestibility of phosphorus in feed phosphates fed to growing pigs. J. Anim. Sci. Vol 100, Issue 12, skac350, doi.org/10.1093/jas/skac350. Link to full text.

Cristobal, M., J. Blair, P. L. Utterback, H. H. Stein, and C. M. Parsons. 2023. Determination of TME_n, standardized amino acid digestibility, and phosphorus digestibility in soybean expellers produced from a new variety soybeans fed to chickens. Poultry Sci. 102 (E-suppl. 1): 37. Link to abstract.

Cristobal, Minoy A., Carl M. M. Parsons, Hans H. Stein. 2023. Concentrations of Digestible and Metabolizable Energy, Ileal Digestibility of Amino Acids, and Digestibility of Phosphorus in a New Variety of Soybeans Fed to Growing Pigs. J. Anim. Sci. Volume 101, Issue Supplement 2, Pages 51 - 52, doi.org/10.1093/jas/skad341.056. Link to abstract.

Espinosa, C. D., J. D. Ward, and H. H. Stein. 2023. Increasing phosphorus digestibility in novel corn fermented products. National Hog Farmer, July 27, 2023.

New sources of high protein corn co-products have been recently developed and may be included in diets fed to pigs. Phytase is often employed during fermentation in the bioethanol process to improve the efficiency of fermentation. However, the use of phytase during fermentation may impact the nature of phosphorus (P) in any post fermentation products, which could subsequently alter the levels of phytate-bound and non-phytate P. As a consequence, this may influence digestibility and concentration of digestible P in any feed product derived from fermentation. Therefore, an experiment was conducted to determine the standardized total tract digestibility (STTD) of P in high protein corn fermented products and in the residual distillers dried grains and solubles (DDGS) produced from a fermentation with or without the use of phytase. It is also the objective of this experiment to test the hypothesis that inclusion of phytase during the fermentation process increases P digestibility in corn co-products.

Lee, Su A , Leidy J. Torres-Mendoza, and Hans H. Stein1. 2022. Effects of 25-hydroxycholecalciferol (25-OH-D3) and 1-hydroxycholecalciferol (1-OH-D3) on serum bone biomarkers and calcium and phosphorus balance and concentrations of energy in diets without or with microbial phytase fed to sows in late gestation. Journal of Animal Science, 2022, 100, 1–8. doi.org/10.1093/jas/skac299.

Field peas have been produced mainly for human consumption, but lastly, the industry has been included in diets fed to livestock due to its content of starch and protein. In diets for swine, only peas that are harvested at maturity are used. Almost 80% of P in non-oilseed legumes is bound to phytate, and pigs do not synthesize an adequate amount of endogenous phytate to liberate the P bound to phytate. Therefore, the digestibility of P in field peas is relatively low. Values for apparent total tract digestibility (ATTD) and standardized total tract digestibility (STTD) of P in field peas have been reported, but there are no comparative values for the ATTD and STTD of P among different varieties of field peas at different particle sizes. Therefore, the objective of this experiment was to test the hypothesis that there are no differences in the ATTD and the STTD of P among different sources of field peas fed to young pigs and the second hypothesis was that there is a linear increase in the ATTD and STTD of P as the particle size of field peas increases.

Lee, S. A, and H. H. Stein. 2022. Vitamin D and vitamin D metabolites impact on calcium and phosphorus balance in gestating sows. Proc. 21th Annual Midwest Swine Nutrition Conf. Danville, IN, Sep. 8, 2022. Pages 39-43. Link to full text.