Strategic Selenium Management: Natural Biofortification of Grazing Livestock with Selenium to Avert Selenium Deficiency and Enhance the Nutritional Value of Food Products.

Authors: Taylor, Joshua - Bret

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 7/5/2011
Publication Date: 12/1/2011
Citation: Taylor, J.B. 2011. Strategic Selenium Management: Natural Biofortification of Grazing Livestock with Selenium to Avert Selenium Deficiency and Enhance the Nutritional Value of Food Products. In Selenium: Global Perspectives of Impacts on Humans, Animals and the Environment. Hefei, China: University of Science and Technology of China Press. p.17-18.

Interpretive Summary: Efficient and effective management of Se deficiency is required to sustain profitability of grazing-based livestock operations. Selenium deficiency increases morbidity and mortality rates, reduces reproduction rates, and reduces yield and quality of marketable products. Therefore, producers must provide supplemental Se to abate Se deficiency. Selenomethionine (SeMet) replaces methionine during protein synthesis. Thus, SeMet is conserved as methionine, and the Se in SeMet is thereby sequestered in the protein pools. Within the context of livestock production, body protein (e.g., skeletal muscle) can be biofortified with Se when SeMet-rich diets are fed. Therefore, the long-term Se status of livestock is significantly enhanced, because of the long half-life of SeMet compared with sodium selenite. Grains and forages harvested in seleniferious regions (e.g. South Dakota) of the U.S. are rich in Se. Similar to when Se-enriched yeast was fed, feeding Se-rich wheat grain resulted in rapid biofortification of lambs with Se. Use of raw grains as livestock feed is not always practical because of direct competition with human food and energy industries. However, coproducts developed from milling raw grains are commonly used in diets fed to ruminants. Uniquely, wheat coproduct fractions (e.g. middlings) are increasingly enriched with Se as the milling advances through the breaking processes. Coproduct fractions from milling Se-rich grains, such as wheat, were used in diets to safely, rapidly, and simultaneously biofortify livestock and their offspring with Se. Such biofortification enhanced the long-term (i.e. 4 to 11 months) Se status of grazing livestock and resulted in naturally-biofortified Se-rich food products for humans (e.g. meat and milk). Ultimately, use of Se-rich milling coproducts as a component of livestock nutritional strategies enables livestock producers to avert Se deficiency and sustain profitable production, may result in added value to harvested feeds that are naturally rich in Se, and provides a means to naturally biofortify foods with Se for human consumption.

Technical Abstract: : Efficient and effective management of Se deficiency is required to sustain profitability of grazing-based livestock operations. Selenium deficiency increases morbidity and mortality rates, reduces reproduction rates, and reduces yield and quality of marketable products. Therefore, producers must provide supplemental Se to abate Se deficiency. Selenomethionine (SeMet) replaces methionine during protein synthesis. Thus, SeMet is conserved as methionine, and the Se in SeMet is thereby sequestered in the protein pools. Within the context of livestock production, body protein (e.g., skeletal muscle) can be biofortified with Se when SeMet-rich diets are fed. Therefore, the long-term Se status of livestock is significantly enhanced, because of the long half-life of SeMet compared with sodium selenite. Grains and forages harvested in seleniferious regions (e.g. South Dakota) of the U.S. are rich in Se. Similar to when Se-enriched yeast was fed, feeding Se-rich wheat grain resulted in rapid biofortification of lambs with Se. Use of raw grains as livestock feed is not always practical because of direct competition with human food and energy industries. However, coproducts developed from milling raw grains are commonly used in diets fed to ruminants. Uniquely, wheat coproduct fractions (e.g. middlings) are increasingly enriched with Se as the milling advances through the breaking processes. Coproduct fractions from milling Se-rich grains, such as wheat, were used in diets to safely, rapidly, and simultaneously biofortify livestock and their offspring with Se. Such biofortification enhanced the long-term (i.e. 4 to 11 months) Se status of grazing livestock and resulted in naturally-biofortified Se-rich food products for humans (e.g. meat and milk). Ultimately, use of Se-rich milling coproducts as a component of livestock nutritional strategies enables livestock producers to avert Se deficiency and sustain profitable production, may result in added value to harvested feeds that are naturally rich in Se, and provides a means to naturally biofortify foods with Se for human consumption.