Abstract: Background – Vitamin E is an essential micronutrient, protective against oxidative damage. Vitamin E deficiency is linked to development of neuromuscular disorders in horses. Deficiency is observed in humans hospitalized for critical illness, potentially due to decreased intake or increased oxidative damage. Hypothesis/Objectives – Serum vitamin E concentration [vitE] will decrease from time of admission to discharge, with [vitE] associated with duration of hospitalization. Animals – Client-owned horses admitted as patients or companions through the emergency service at a tertiary referral center were enrolled. 40 adult horses and 20 foals met inclusion criteria (hospitalized for ≥5 days, no vitamin E supplementation, age ≤3 months or ≥1 year). Methods – A cohort study was performed. Whole blood was drawn at the time of admission and discharge. Serum [vitE] was obtained using high-performance liquid chromatography. The data were non-normally distributed and subsequently analyzed with Spearman rank test with p of <.5 for significance. Results – Duration of hospitalization had no significant effect on [vitE] (p=.85) when accounting for all age patients. Mean [vitE] did vary between adults (3.6 ppm), and foals (4.8 ppm) (p=.1). When comparing timepoints this difference in vitamin E concentration in adults and foals was maintained for both [vitE]admit and [vitE]discharge. In foals, IgG concentration was inversely correlated with [vitE]admit (p=.003). Seven adult horses and 2 foals (15% of study population) were considered deficient at admission.Conclusions and clinical importance – The average horse admitted to the hospital does not require vitamin E supplementation to maintain adequate [vitE].
