Effect of Dietary Supplementation with Vitamin E and Selenium in Thoroughbred Horses on the Concentration of F2-isoprostanes in the Blood Plasma as a Marker of Lipid Peroxidation

Abstract

The objective of this study was to assess the effect of vitamin E and selenium (Se) supplementation on the plasma levels of F 2 -isoprostanes as a marker of oxidative stress in horses in their training period. Twelve healthy 3-year-old English thoroughbred horses were divided into two groups: control (n = 6) and experimental (n = 6). Feeding rations were adapted to a moderate workload. The horses of the experimental group received supplements of DL--tocopheryl acetate E (2 250 mg/day/horse) and of sodium selenite (0.5 mg/day/horse). The plasma concentrations of both antioxidants and F 2 -isoprostanes were monitored on days 0, 44 and 70. After 70 days of supplementation, the concentrations of selenium in the experimental group were significantly higher (P  0.05) compared to the beginning of the experiment (mean ± SE: 135. ). In the horses of the experimental group, plasma -tocopherol levels significantly increased from the 44 th day of supplementation compared to the beginning of the study as well to the control group (5.23 ± 0.52 mg·l -1 vs. 2.45 ± 0.25 mg·l -1 or 3.46 ± 0.34 mg·l -1 , respectively). The plasma concentration of F 2 -isoprostanes tended to be lower in the experimental group at the end than at the beginning of monitoring (156.8 ± 12.89 pg·ml -1 vs. 170.3 ± 60.8 pg·ml -1 ), although the control group showed the opposite trend (181.2 ± 15.67 pg·ml -1 vs. 137.0 ± 47.05 pg·ml -1 ). Nevertheless, none of these differences were significant because of the large variability of the individual values. It can be stated that supplementation of the diet used with selenium and vitamin E caused a non-significant decrease of F 2 -isoprostane concentration in the blood plasma only, and a significant increase of plasma concentrations of these antioxidants. The variation of isoprostane levels probably reflected rather the individual responses of the horses' organisms to the training workload.

Effect of evening primrose oil on biochemical parameters of thoroughbred horses under maximal training conditions

“…For this reason it is necessary to supplement the antioxidants perorally. The most common antioxidants added to horse diets are vitamin E and C, alternatively a combination of both (White et al 2001;Williams et al 2004), or vitamin E and some forms of selenium (de Mof-farts et al 2005;Hartlova et al 2008). Human, as well as veterinary medicine, is currently focused on natural substances with a distinct antioxidative effect.…”