title: A dynamic evaluation of the bioavailability of the free and ester forms of vitamin E administered intramuscularly to beef cattle.
abstract: Two trials were carried out to evaluate the bioavailability of 2 vitamin E components, D-alpha-tocopherol and DL-alpha-tocopherol acetate administered to 6 cattle intramuscularly (IM). In the first trial, 6 heifers received 3 doses at 28-d intervals of 13,500 IU, 4,500 IU, and 4,500 lu respectively of D-alpha-tocopherol. The blood plasma alpha-tocopherol curve area (AUC) and maximum increase (Cmax) were higher following administration of the 13,500 IU than of the 4,500 IU doses. The lowest AUC and Cmax were observed after the third injection of D-alpha-tocopherol. However, no difference was found for the adjusted values of AUC between the second and third dose. Time to maximum increase was shorter following the 13,500 IU dose than the 4,500 IU. The data following administration of 13,500 IU vitamin E fitted to a 2-compartment open model. In a second trial, 6 heifers received 2 doses IM of 4,500 IU DL-alpha-tocopherol acetate at 28-d intervals. Differences were not observed for AUC, Cmax and the time required for maximum plasma concentration between the 2 phases of 28 d in the acetyl forms-dosed cattle.
authors.affiliation: Agriculture Canada, Experimental Farm, Nappan, Nova Scotia, Canada.
authors.forename: N
authors.initials: N
authors.lastname: Hidiroglou
authors.forename: L F
authors.initials: LF
authors.lastname: Laflamme
mesh_terms: D000042:Absorption; D000818:Animals; D001682:Biological Availability; D002417:Cattle / Q000378:metabolism*; D005260:Female; D006207:Half-Life; D007273:Injections, Intramuscular / Q000662:veterinary; D024505:Tocopherols; D014810:Vitamin E / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000493:pharmacokinetics*; D024502:alpha-Tocopherol / Q000031:analogs & derivatives*
chemical_list: D014810:Vitamin E; D024502:alpha-Tocopherol; D024505:Tocopherols