title: Twenty-five hydroxycholecalciferol as a cholecalciferol substitute in broiler breeder hen diets and its effect on the performance and general health of the progeny.
abstract: An experiment was conducted with broiler breeder hens to determine the relative biological value of 25-hydroxycholecalciferol (25-OHD3) compared with cholecalciferol (vitamin D3) for hen-day egg production, hatchability, embryo mortality (early, 1 to 10 d of incubation, late, 11 to 21 d), and body ash of the progeny. The study was conducted with 73-to-90-wk-old molted Ross broiler breeder hens in an environment excluding ultraviolet light. A basal vitamin D3 deficient diet supplemented with 4 levels of vitamin D3 (0, 3,125, 12,500, and 50,000 ng/kg of diet) and 2 levels of 25-OHD3 (3,125 and 12,500 ng/kg of diet) was fed. The relative biological values of 25-OHD3 in comparison to vitamin D3, using slope ratio techniques, were 138, 133, 128, and 111% for hen-day egg production, hatchability, late embryo mortality, and body ash of the progeny,, respectively (average = 128%). When comparing 25-OHD3 against D3 at the 3,125 ng/kg level, the relative biological values were 209, 167, 400, and 108% for the same criteria, respectively (average = 221%). However, at the 12,500 ng/kg level no statistical differences between 25-OHD3 and D3 were observed (average = 108%). Four trials were conducted to determine the effect of the maternal diet on the performance and leg abnormalities of the hens' progeny. In experiment 1, no vitamin D was added to the corn-soybean meal basal diet fed to the chicks, and in experiments 2, 3, and 4 the basal diet was supplemented with 27.5 microg of D3/kg of diet. In the progeny study, the average relative biological value of 25-OHD3 at the 3,125 and 12,500 ng/kg levels were 115 and 101%, respectively. The potency of 25-OHD3 in relation to vitamin D3 depended on the level tested. When comparing vitamin D sources, 25-OHD3 had greater potency than D3 only at very low levels of supplementation.
authors.affiliation: Department of Poultry Science, Poultry Science Building, University of Georgia, Athens, Georgia 30602-2772, USA.
authors.forename: A
authors.initials: A
authors.lastname: Atencio
authors.forename: G M
authors.initials: GM
authors.lastname: Pesti
authors.forename: H M
authors.initials: HM
authors.lastname: Edwards
mesh_terms: D000375:Aging; D000821:Animal Feed; D000818:Animals; D002112:Calcifediol / Q000008:administration & dosage*; D002642:Chick Embryo / Q000187:drug effects / Q000254:growth & development; D002645:Chickens / Q000254:growth & development*; D002762:Cholecalciferol / Q000008:administration & dosage; D019587:Dietary Supplements; D004305:Dose-Response Relationship, Drug; D005260:Female; D005298:Fertility; D008297:Male; D015430:Weight Gain
chemical_list: D002762:Cholecalciferol; D002112:Calcifediol