| Five experiments were conducted to investigate the effects of level, form, and methods of vitamin E supplementation on $alpha$-tocopherol in serum, other blood components, and tissues in sheep and cattle. Experiment 1 investigated effects of four levels of vitamin E (125, 250, 500, and 1,000 IU) on serum tocopherol in sheep after a single i.m. injection of DL-$alpha$-tocopherol. Serum tocopherol increased rapidly to maximum concentration (Cmax) during the first 8 to 12 h, followed by a rapid decline. Cmax, area under the concentration time/curve, and time taken to reach pretreatment values increased ($P < 5.0$) with dosage. In experiment 2, sheep received single or multiple i.m. injections or DL-$alpha$-tocopherol acetate or DL-$alpha$-tocopherol and (or) oral supplementation of DL-$alpha$-tocopherol acetate. Multiple injections with DL-$alpha$-tocopherol increased ($P < .05$) serum tocopherol rapidly to Cmax and declined to levels higher than pretreatment. No acetate or alcohol forms were detected in serum following injections with DL-$alpha$-tocopherol acetate. Multiple injections with DL-$alpha$-tocopherol produced multiple peaks. Pancreas and liver attained the highest ($P < 5.0$) tocopherol. Experiment 3 investigated effects of pre- and postpartum dietary supplementation of vitamin E (0, 15, 30, and 60 IU) on placental and mammary gland transfer in sheep. Supplemental E increased serum tocopherol ($P .05$) indicating poor placental transfer. Lamb serum tocopherol increased linearly ($P < .05$) following colostrum ingestion. There were linear treatment effects on tocopherol in colostrum and milk. Experiment 4 evaluated serum, platelets, and muscle tocopherol or serum tocopherol/cholesterol + triglycerides as indicators of vitamin E status in sheep. By d 60 these indices increased ($P < .05$) with intake (0, 15, 30, and 60 IU E) with platelet tocopherol most sensitive to vitamin E intake. Experiment 5 evaluated serum, red blood cells, and tissue tocopherol or serum tocopherol/cholesterol + triglycerides as indices of vitamin E status in cattle. There were linear relationships ($P < .05$) between these indices (excluding red blood cells) and E intake (0, 500, 1500, and 3000 IU). There was a linear relationship ($P < .05$) between liver and serum tocopherol or serum tocopherol/cholesterol + triglycerides. |
