Use of 1 alpha-hydroxyvitamin D3 to prevent bovine parturient paresis. VI. Concentrations of vitamin D metabolites and vitamin D3 equivalence in milk.
Concentration of vitamin D metabolites was determined in the milk of control and 1 alpha-hydroxyvitamin D3-injected (700 micrograms) cows that calved 36 to 43 h after treatment. Milk samples were taken 60 h after calving. Concentrations of vitamin D, 25-hydroxyvitamin D, 24,25-dihydroxyvitamin D, and 1,25-dihydroxyvitamin D in milk of the control cows were 372 +/- 24, 264 +/- 68, 68 +/- 26, and 21 +/- 3 ng/L, respectively. Concentrations of vitamin D metabolites in the milk of the treated cows did not differ significantly from those of controls. Concentration of 1 alpha-hydroxyvitamin D3 in milk of treated cows was less than 20 ng/L. In a second experiment, cows were injected twice, at 72-h intervals, with 350 micrograms 1 alpha-hydroxyvitamin D3. Milk was taken 60 h after parturition from cows that calved 37 to 60 h after the second injection. The vitamin D3 equivalence of the milk was 40 +/- 3 IU/L. Results indicate that injection of 700 micrograms 1 alpha-hydroxyvitamin D3 did not affect the concentration of vitamin D metabolites or the vitamin D3 equivalence of milk taken 60 h after calving.
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000188:drug therapy / Q000378:metabolism / Q000517:prevention & control*; D002762:Cholecalciferol / Q000032:analysis / Q000378:metabolism*; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006887:Hydroxycholecalciferols / Q000627:therapeutic use*; D008892:Milk / Q000032:analysis*; D010319:Parturient Paresis / Q000188:drug therapy / Q000378:metabolism / Q000517:prevention & control*; D011247:Pregnancy; D014807:Vitamin D / Q000032:analysis / Q000378:metabolism*
D006887:Hydroxycholecalciferols; D014807:Vitamin D; D002762:Cholecalciferol; C008088:alfacalcidol