Pasture-finishing of bison improves animal metabolic health and potential health-promoting compounds in meat

Authors: VAN VLIET, STEPHAN - Utah State University; BLAIR, AMANDA - South Dakota State University; HITE, LYDIA - South Dakota State University; CLOWARD, JENNIFER - Utah State University; WARD, ROBERT - Utah State University; KRUSE, CARTER - Turner Enterprises, Inc; VAN WIETMARCHEN, HERMAN - Louis Bolk Institute; VAN EEKEREN, NICK - Louis Bolk Institute; Kronberg, Scott; PROVENZA, FRED - Utah State University

Submitted to: Journal of Animal Science and Biotechnology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/31/2023
Publication Date: 4/1/2023
Citation: Van Vliet, S., Blair, A.D., Hite, L.M., Cloward, J., Ward, R.E., Kruse, C., Van Wietmarchen, H.A., Van Eekeren, N., Kronberg, S.L., Provenza, F.D. 2023. Pasture-finishing of bison improves animal metabolic health and potential health-promoting compounds in meat. Journal of Animal Science and Biotechnology. 14:49. https://doi.org/10.1186/s40104-023-00843-2.
DOI: https://doi.org/10.1186/s40104-023-00843-2

Interpretive Summary: More consumers are interested in pasture-finished (i.e., grass-fed) meat. But there are questions about its nutritional make-up. Therefore, we studied how pasture-finishing or pen-finishing affected chemical compounds in North American bison meat. Out of 1570 profiled compounds, 671 (43%) differed between pasture- and pen-finished bison meat. Pasture-finished bison broadly had additional potential health-promoting compounds in their meat compared to pen-fed bison. However, our data does not indicate that meat from pen-finished bison is unhealthy. Irrespective of finishing practice the bison meat contained a favorable omega 6:3 ratio and amino acid and vitamin profile. This information is useful to bison producers, and to consumers and nutrition professionals in better understanding how the chemical compounds in meat can be affected by the way the bison are finished.

Technical Abstract: Growing consumer interest in pasture-finished meat (i.e., grass-fed) has raised questions about its nutritional composition. Therefore, we determined the impact of two common finishing systems for North American bison (pasture-finished or pen-finished on concentrates for 146 days) on metabolomic, lipidomic, and fatty acid profiles of striploins (M. longissimus lumborum). Six hundred and seventy-one out of 1570 (43%) profiled compounds differed between pasture- and pen-finished conditions (20 animals per group) (all, P<0.05). Relative to pasture-finished animals, the muscle of pen-finished animals displayed markers of elevated glucose (~1.6-fold), triglycerides (~2-fold), oxidative stress (~1.5-fold), and proteolysis (~1.2-fold). In contrast, pasture-finished animals displayed improved mitochondrial (~1.3-fold higher levels of various Krebs cycle metabolites) and carnitine metabolism (~3 higher levels of long-chain acyl carnitines) (all P<0.05). Pasture-finishing also concentrated higher levels of phenolics (~ 2.3-fold), alpha-tocopherol (~5.8 fold), carotene (~2.0 fold), and very long-chain fatty acids (~1.3-fold), while having lower levels of a common advanced lipoxidation (4-hydroxy-nonenal-glutathione; ~2-fold) and glycation end-products (N6-carboxymethyllysine; ~1.7-fold) (all P<0.05). In contrast, vitamins B5, B6, and C, gamma-tocopherols, and three phenolics commonly found in alfalfa were ~2.5-fold higher in pen-finished animals (all P<0.05); suggesting some concentrate feeding, or grazing plants rich in those compounds, may be beneficial. Pasture-finishing (i.e., grass-fed) broadly improved bison metabolic health and accumulated additional potential health-promoting compounds in their meat compared to concentrate finishing in confinement (i.e., pen-finished). However, our data does not indicate that meat from pen-finished bison is unhealthy since irrespective of finishing practice the bison meat contained a favorable omega 6:3 ratio (<3.2) and amino acid and vitamin profile.