Effect of parenteral vitamin D3 on plasma 25-hydroxyvitamin D3 concentration in sheep.
Vitamin D3 ranging in total amount from 10(5) iu (2.5 mg) to 9 X 10(5) iu (22.5 mg) was given intramuscularly either as a single injection or in three aliquots at three-weekly intervals to housed nonpregnant ewes on a vitamin D deficient diet. The effects on plasma concentrations of 25-hydroxyvitamin D3 (25-OHD3), the major metabolite of vitamin D, were monitored. The increase in plasma 25-OHD3 showed a large variation between animals and was related to, but not proportional to, the dose. None of the treatments produced 25-OHD3 concentrations greater than those in grazing sheep in summer. Repeated dosing provided for more efficient use of the injected vitamin D3.
D000818:Animals; D002112:Calcifediol / Q000097:blood*; D002118:Calcium / Q000097:blood; D002762:Cholecalciferol / Q000008:administration & dosage / Q000494:pharmacology*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006909:Hydroxyproline / Q000097:blood; D007273:Injections, Intramuscular / Q000662:veterinary; D010758:Phosphorus / Q000097:blood; D012756:Sheep / Q000097:blood*
D002762:Cholecalciferol; D010758:Phosphorus; D002112:Calcifediol; D006909:Hydroxyproline; D002118:Calcium