Assessment of vitamin E concentrations in serum and cerebrospinal fluid of horses following oral administration of vitamin E.
OBJECTIVE
To determine concentrations of alpha-tocopherol in serum and CSF of healthy horses following administration of supplemental vitamin E in feed.


METHODS
10 healthy adult horses.


METHODS
Horses were allocated to receive supplemental d-alpha-tocopherol (1,000 U/d [group A; n=5] or 10,000 U/d [group B; 5]) in feed for 10 days. Blood samples were collected before (baseline), during, and at intervals for 10 days after discontinuation of vitamin E administration for assessment of serum alpha-tocopherol concentration. Cerebrospinal fluid samples were collected prior to and 24 hours after cessation of vitamin E administration. Alpha-tocopherol concentrations in serum and CSF samples were analyzed via high-performance liquid chromatography; changes in those values during the treatment period were compared between groups, and the relationship of serum and CSF alpha-tocopherol concentrations was evaluated.


RESULTS
In both groups, serum alpha-tocopherol concentration increased significantly from baseline during vitamin E administration; values in group B were significantly greater than those in group A during and after treatment. At the end of vitamin E administration, CSF alpha-tocopherol concentration was not significantly greater than the baseline value in either group; however, the increase in CSF concentration was significant when the group data were combined and analyzed. Serum and CSF alpha-tocopherol concentrations were significantly correlated at baseline for all horses, but were not strongly correlated after 10 days of vitamin E administration.


CONCLUSIONS
In healthy horses, daily oral administration of supplemental vitamin E in feed resulted in increases in serum and CSF alpha-tocopherol concentrations.
Veterinary Medical Teaching Hospital, School of Veterinary Medicine, University of California, Davis, CA 95616, USA.
Jamie K
JK
Higgins
Birgit
B
Puschner
Philip H
PH
Kass
Nicola
N
Pusterla
D000284:Administration, Oral; D000818:Animals; D019587:Dietary Supplements; D005260:Female; D006736:Horses / Q000097:blood* / Q000134:cerebrospinal fluid*; D008297:Male; D011897:Random Allocation; D018709:Statistics, Nonparametric; D014810:Vitamin E / Q000008:administration & dosage*; D024502:alpha-Tocopherol / Q000097:blood* / Q000134:cerebrospinal fluid*
D014810:Vitamin E; D024502:alpha-Tocopherol