Effect of vitamin E supplementation in diets with a low concentration of selenium on mammary gland health of dairy cows.
Sixty-six cows and heifers (Holsteins and Jerseys) were assigned to one of three treatments at 60 d before anticipated calving. Treatment 1 consisted of 100 IU/d of supplemental vitamin E during the dry period and 100 IU/d during the first 30 d of lactation. Treatment 2 was 1000 IU/d of vitamin E during the dry period and 500 IU/d during lactation. Treatment 3 was 1000 IU/d of vitamin E during the first 46 d of the dry period, 4000 IU/d during the last 14 d of the dry period, and 2000 IU/d during lactation. Plasma concentrations of alpha-tocopherol decreased at calving for cows fed dietary treatments with low or intermediate concentrations of vitamin E, but not for cows fed the high vitamin E treatment. High dietary vitamin E increased concentrations of alpha-tocopherol in blood neutrophils at parturition, but no difference was found for the other two treatments. The percentage of quarters with new infections at calving was not different (32.0%) between cows receiving treatments that contained low and intermediate concentrations of vitamin E but was reduced (11.8%) in cows receiving the high vitamin E treatment. Clinical mastitis affected 25.0, 16.7, and 2.6% of quarters during the first 7 d of lactation for cows receiving the low, intermediate, and high vitamin E treatments, respectively. Cows with plasma concentrations of alpha-tocopherol < 3.0 micrograms/ml at calving were 9.4 times more likely to have clinical mastitis during the first 7 d of lactation than were cows with plasma concentrations of alpha-tocopherol > 3.0 micrograms/ml.
Weiss
W P
WP
Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster 44691, USA.
Hogan
J S
JS
Todhunter
D A
DA
Smith
K L
KL
D000821:Animal Feed; D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000502:physiology*; D002784:Cholesterol / Q000097:blood; D003126:Colostrum; D004032:Diet; D005260:Female; D007958:Leukocyte Count; D008321:Mammary Glands, Animal / Q000502:physiology*; D008414:Mastitis, Bovine / Q000517:prevention & control; D009504:Neutrophils; D012643:Selenium / Q000008:administration & dosage* / Q000097:blood; D014810:Vitamin E / Q000008:administration & dosage* / Q000097:blood
D014810:Vitamin E; D002784:Cholesterol; D012643:Selenium