Nutritional science really does not know enough about selenium metabolism. As a result Horse Guard has funded a selenium study at West Texas A&M. This study was conducted by Dr. Kelsey J. Nonella. The study takes selenium sufficient horses and feeds them hay from the Pacific Northwest (Central Oregon), which is extremely selenium deficient.
West Texas A&M monitored the depletion of selenium in the horses blood over time. This phase was complete in Jan. 2014, making all horses significantly deficient in roughly 4 months (112 days).
On day 113, the team started the repletion phase and for the next 112 days monitored the repletion phase. The horses were divided. Both groups were still fed the same extremely selenium deficient (Pacific Northwest) hay. The difference was, group 1 had 3 mg of organic selenium added to their diet (Horse Guard), while group 2 had 1 mg of organic selenium added to their diet.
The results were amazing. Below is Dr. Nonella’s synopsis and summary of the trail. Click on the link below for the whole dissertation.
- THE EFFECTS OF SELENIUM DEPLETION AND REPLETION ON WHOLE BLOOD SELENIUM CONCENTRATIONS AND ERYTHROCYTE GLUTATHIONE PEROXIDASE ACTIVITY IN MODERATELY-EXERCISED HORSES
Synopsis: Selenium is an essential trace mineral that serves as an antioxidant, and aids in both immune function as well as thyroid hormone metabolism. The objective of this research was to evaluate the effects of Se depletion and repletion on whole blood Se concentrations and erythrocyte glutathione peroxidase (RBC GSH- Px) activity.
Summary: Read more about the details on Dr. Kelsey’s doctoral research in her dissertation. She fed horses Northwest hay without selenium supplementation for four months, and then added selenium supplementation for four additional months. During the depletion and repletion she monitored the status of selenium in horses. She found that by the end of depletion, horses were close to clinically selenium deficient, and that four months of selenium supplementation was not enough time to get the horses back to adequate selenium levels. This drives home the point that it is critical to continuously supplement your horse to ensure optimal health.
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