title: Comparison of plasma concentrations of vitamin D and its metabolites in young and aged domestic animals.
abstract: 1. Vitamin D and its metabolites were measured in the plasma of five species of rural domestic animals. 2. Concentration of 1,25-dihydroxyvitamin D was higher (P less than 0.01) in young animals (range 24-118 pg/ml, means +/- SD = 72.0 +/- 30.0) than in adult animals (range 14-67 pg/ml, means +/- SD = 40.2 +/- 22.6). 3. 25-Hydroxyvitamin D3-26,23 lactone was present only in the chick and the pig. 4. Unsheared sheep appeared to be inefficient utilizers of the photochemical conversion of 7-dehydrocholesterol to vitamin D3. 5. Conversion of 25-hydroxyvitamin D to 24,25-dihydroxyvitamin D was most efficient in species with high plasma phosphorus concentrations (pig, sheep).
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3; D000375:Aging; D000818:Animals; D000829:Animals, Domestic / Q000097:blood*; D002112:Calcifediol / Q000031:analogs & derivatives / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002417:Cattle; D002645:Chickens; D004100:Dihydroxycholecalciferols / Q000097:blood; D005260:Female; D008297:Male; D012756:Sheep; D013552:Swine; D014422:Turkeys; D014807:Vitamin D / Q000097:blood*
chemical_list: D004100:Dihydroxycholecalciferols; D014807:Vitamin D; D015650:24,25-Dihydroxyvitamin D 3; C026396:calcifediol lactone; D002117:Calcitriol; D002112:Calcifediol