title: 24-hydroxylation of 25-hydroxyvitamin D3: is it required for embryonic development in chicks?
abstract: As shown previously, laying hens given 1,25-dihydroxyvitamin D3 as their sole source of vitamin D produce fertile eggs having normal shells, but only 35 to 55 percent of the embryos are normal. Giving these hens additional 25-hydroxyvitamin D3, 24,25-dihydroxyvitamin D3, or 24,24-difluoro-25-hydroxyvitamin D3 at 1.25 nanomoles per day resulted in 90 to 100 percent normal embryos, and hence, hatchability. Since 24,24-difluoro-25-hydroxyvitamin D3 cannot be 24-hydroxylated, 24-hydroxylation is not required for this function of 25-hydroxyvitamin D3.
mesh_terms: D015650:24,25-Dihydroxyvitamin D 3; D000821:Animal Feed; D000818:Animals; D002112:Calcifediol; D002117:Calcitriol / Q000031:analogs & derivatives / Q000494:pharmacology; D002642:Chick Embryo / Q000254:growth & development*; D002645:Chickens / Q000378:metabolism; D004100:Dihydroxycholecalciferols / Q000494:pharmacology; D005260:Female; D006887:Hydroxycholecalciferols / Q000378:metabolism* / Q000494:pharmacology; D006900:Hydroxylation
chemical_list: D004100:Dihydroxycholecalciferols; D006887:Hydroxycholecalciferols; D015650:24,25-Dihydroxyvitamin D 3; C023370:24,24-difluoro-1,25-dihydroxyvitamin D3; D002117:Calcitriol; D002112:Calcifediol