| Autor: |
G Y, Miller, P C, Bartlett, R J, Erskine, K L, Smith |
| Rok vydání: |
1995 |
| Předmět: |
|
| Zdroj: |
Journal of the American Veterinary Medical Association. 206(9) |
| ISSN: |
0003-1488 |
| Popis: |
Supplementation of selenium and vitamin E to enhance disease resistance in dairy cattle has become common, particularly to prevent periparturient reproductive disorders and mastitis. To establish reference values for serum vitamin E and selenium concentrations in postparturient dairy cattle and to determine whether serum concentrations of these micronutrients varied with season and stage of lactation, cows from a stratified random sample of 50 herds were studied for 1 year. Blood samples were collected from each of the 50 study herds twice, from the 10 most recently parturient cows or from 10% of the herd, whichever was greatest. Mean concentration of vitamin E and selenium was 2.55 micrograms/ml and 78.12 ng/ml, respectively. Vitamin E concentrations were significantly (P0.05) higher during the summer and fall than during the winter and spring. Selenium concentrations were significantly (P0.05) lower during the summer and fall than during the winter and spring. Herd, season of blood sample collection, and time since parturition were significant (P0.02) in explaining variation in vitamin E and selenium concentrations. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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