Lipid peroxidation can cause cell damage. Also, Vitamin E may interact with membrane phospholipids and be an important structural component of membranes. Selenium is part of glutathione peroxidase and converts hydroperoxides to less toxic alcohols, and with Vitamin E may help maintain cellular integrity. Selenium may also increase uptake of Vitamin E from the Gl tract and affect transport into tissues. Signs of deficiency are most common in foals from birth to 7 months of age.
Affected neonates are weak at or shortly after birth.
Unsteadiness can progress to recumbency and they may have difficulty rising or be unable to rise. Respiratory problems and sometimes dysphagia lead to aspiration pneumonia. Older foals with the acute form have a sudden onset of lethargy and stiff gait which progresses to recumbency, or they may have sudden exercise induced recumbency and inability to rise leading to death within 5 hours due to pulmonary edema and myocardial failure. Painful subcutaneous swellings, especially over the rump, ventral abdominal wall and nuchal crest can occur. This can progress to steatitis.