Pd. Siciliano et al., EFFECT OF DIETARY VITAMIN-E SUPPLEMENTATION ON THE INTEGRITY OF SKELETAL-MUSCLE IN EXERCISED HORSES, Journal of animal science, 75(6), 1997, pp. 1553-1560
The effect of vitamin E intake on indicators of muscle integrity was s
tudied in exercised horses. Nineteen horses were blocked by sex and th
en assigned to one of three diets: no supplemental vitamin E (BASAL),
BASAL plus 80 IU of supplemental vitamin E/kg DM (80), or BASAL plus 3
00 IU of supplemental vitamin E/kg DM (300). The BASAL diet contained
less than 44 IU of vitamin E/kg DM, but it was adequate in all other n
utrients. During the 90-d treatment period, horses were exercised 5 d/
wk; in addition, serum and middle gluteal muscle alpha-tocopherol conc
entrations were measured at 0, 30, and 90 d. All horses performed a re
peated submaximal exercise test (RSET) at the end of the 90-d period.
The following were measured before and after the RSET: alpha-tocophero
l, thiobarbituric acid reactive substances (TBARS), conjugated diene (
CD) concentrations of the middle gluteal muscle, and serum creatine ki
nase (CK) and aspartate aminotransferase (AST) activities. Serum a-toc
opherol concentrations of horses receiving the BASAL and 80 diets decr
eased (P <.05 and P <.06, respectively) during the 90-d treatment peri
od but did not change in horses receiving the 300 diet. Serum and musc
le alpha-tocopherol concentrations were higher (P <.05) at 30 and 90 d
in horses receiving the 300 diet than in horses receiving the BASAL a
nd so diets. Serum CK and AST activities increased (P <.05) following
RSET but were not affected by dietary vitamin E level. Muscle alpha-to
copherol level did not affect muscle CD or TBARS.