Levels of Selenium May Have Affect on Horses

A recent study looks at the possible effects of different levels of selenium on the immune system in adult horses.

According to researchers from the University of Kentucky, this has been studied in other animals but not extensively in horses.

The study notes the following, via a press release: "The cell-mediated component is responsible for the activation of immune cells. These immune cells can directly attack foreign antigens. In this experiment, twenty-eight adult horses were divided by age and sex. The horses were then randomly assigned to a dietary selenium treatment. Brummer said the first phase lasted 35-weeks. During the first phase, the researchers were aiming to deplete the selenium in the horses that were assigned to the low diet.

"In the next 29-weeks, some the horses that were assigned to low treatments were given additional dietary selenium supplements. Brummer said the horses were either given organic or inorganic selenium supplements. During the last 7 weeks, the horses were given vaccinations. The researchers collected blood samples to evaluate immune response during this time."

Mieke Brummer, PhD student working with the University of Kentucky and Alltech, who was involved in the study, said the evaluation of the vaccination response was not effective and other measures of cell-mediated immunity might suggest that cell-mediated immune function could be suppressed in horses with low levels of selenium.  

 "It is important for horse owners to read feed labels so they can avoid both over-supplementation and under-supplementation of all classes of horses," Lawrence said, via the release.

Yet as the horses involved in the study were not under strenuous exercise or heavy amounts of stress, more studies would need to be performed in order to determine the true effects.

More information regarding the study can be found in the Journal of Animal Science.