VITAMIN-E STATUS OF TURKEY POULTS AS INFLUENCED BY DIFFERENT DIETARY VITAMIN-E SOURCES, A BILE-SALT, AND AN ANTIOXIDANT

An experiment was conducted to determine the effects of level and chemical form of dietary vitamin E on alpha-tocopherol status of poults. The effects of a dietary bile salt and an antioxidant on concentrations of alpha-tocopherol in serum and liver were also tested. Six dietary treatments were obtained by supplementing a com-soybean meal diet with 12 IU of DL-alpha-tocopheryl acetate (TA)/kg (LE), 12 IU of TA plus 800 mg of sodium taurocholate/kg (LB), 12 IU of TA plus 500 mg of ethoxyquin/kg (LS), 12 IU of DT-alpha-tocopheryl polyethylene glycol 1,000 succinate (TPGS)/kg (LT), 100 IU of TA/kg (HE), and 100 IU of TPGS/kg (HT). Growth rate and feed efficiency of poults were unaffected (P >.05) by dietary treatments. The HE diet increased alpha-tocopherol in liver (P < .01) at 14 and 21 days of age. Liver and serum alpha-tocopherol concentrations were unaffected by dietary TPGS (LT and HT diets) at any age. Serum alpha-tocopherol concentration was unaffected by dietary treatments at 5 days of age. The HE diet, however, increased (P < .01) serum alpha-tocopherol tocopherol at 9, 14, and 21 days of age. Age-related changes in alpha-tocopherol concentration were observed. Both liver and serum alpha-tocopherol decreased markedly from 1 to 14 days of age. The HE diet only partly alleviated the reduction of alpha-tocopherol in liver and serum. The water-soluble form of vitamin E, TPGS, dietary sodium taurocholate, or dietary ethoxyquin, did not prevent the marked decline in alpha-tocopherol concentration of liver and serum during the 21-day experiment.