Effect of duration of supplementation of selenium and vitamin E on periparturient dairy cows.
Cows were fed diets either supplemented with .2 ppm Se and 70 IU vitamin E/kg diet DM (21 cows) or unsupplemented (40 cows) during the dry period (approximately 60 d). From parturition to 21 d of lactation, cows were fed diets that were either supplemented with .3 ppm Se and 40 IU/kg vitamin E or unsupplemented. At d 21 following parturition, 18 cows fed the unsupplemented diet were switched to diets containing 0 or .3 ppm supplemental Se and 0 or 40 IU/kg supplemental vitamin E arranged factorially. These diets were fed for the next 32 d. The remaining cows continued their respective diets for 32 d. Plasma Se concentrations averaged .1 microgram/ml for supplemented cows but were .05 micrograms/ml for unsupplemented cows. Plasma Se concentration from cows fed supplemental Se from 21 to 53 d postpartum increased rapidly and were not different from long-term supplemented cows. Whole blood glutathione peroxidase activity was lower in unsupplemented than in supplemented cows. Short-term Se supplementation increased glutathione peroxidase activity above that for unsupplemented animals, but activity was still less than that in long-term supplemented animals. Plasma alpha-tocopherol concentrations at parturition and d 21 postpartum were lower in unsupplemented than in supplemented animals. On d 53 postpartum, no differences in plasma alpha-tocopherol concentrations were found between long-term supplemented and unsupplemented cows. Supplementing vitamin E during the dry period increased alpha-tocopherol content of colostrum.
Weiss
W P
WP
Department of Dairy Science Ohio Agricultural Research and Development Center, Ohio State University, Wooster 44691.
Todhunter
D A
DA
Hogan
J S
JS
Smith
K L
KL
D000818:Animals; D002417:Cattle / Q000097:blood / Q000502:physiology*; D003126:Colostrum / Q000737:chemistry; D004435:Eating; D005260:Female; D007743:Labor, Obstetric / Q000097:blood / Q000187:drug effects*; D007774:Lactation / Q000097:blood / Q000187:drug effects*; D011247:Pregnancy; D011897:Random Allocation; D012643:Selenium / Q000008:administration & dosage* / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage* / Q000032:analysis / Q000097:blood
D014810:Vitamin E; D012643:Selenium