Vitamin Concentration and Function of Leukocytes from Dairy Calves Supplemented with Vitamin A, Vitamin E, and β-Carotene In Vitro

Abstract

Blood neutrophils and pulmonary alveolar macrophages, isolated from calves at 3 and 6 wk of age, were cultured in medium without added vitamins or supplemented with 100 μg/dl of vitamin A, 1000 μg/dl of vitamin E, 100 μg/dl of vitamin A plus 1000 μg/dl of vitamin E, or .25 μg/dl of β-carotene plus 1000 μg/ dl of vitamin E. Macrophage bactericidal activity improved with supplementation of vitamins A plus E compared with supplementation of β-carotene plus E or vitamin E at wk 3. Neutrophil bactericidal activity decreased with all vitamin E treatments at wk 3 and with vitamins E or A plus E at wk 6. Neutrophil phagocytosis improved at wk 3 with supplementations of vitamins A, E, and A plus E. The chemotactic index improved with β-carotene and vitamin E compared with vitamin E alone at wk 3 and at wk 6 with vitamin E compared with vitamin A and control treatments. Retinol content of neutrophils varied at wk 3, but, by wk 6, cells supplemented with vitamins A, E, or A plus E had greater retinol concentrations than control cells. Neutrophil α-tocopherol concentrations at wk 3 increased from those of controls with supplementation of vitamin E or β-carotene and vitamin E, but, at wk 6, vitamin E-supplemented cells were different only from vitamin A-supplemented cells. These data suggest that optimal plasma concentrations of vitamins A and E exist for leukocyte function. © 1994, American Dairy Science Association. All rights reserved.