title: 1 alpha-Hydroxylated cholecalciferol compounds act additively with microbial phytase to improve phosphorus, zinc and manganese utilization in chicks fed soy-based diets.
abstract: Seven experiments were conducted to determine the efficacy of 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] and microbial phytase in improving P, Zn and Mn utilization of chicks fed P, Zn- and Mn-deficient soy protein diets containing surfeit levels of cholecalciferol. Efficacy of 1 alpha-hydroxycholecalciferol (1 alpha-OH D3) was also studied. A dose titration study indicated that supplemental phytase at 1200 units/kg diet would increase bone ash by at least 65% when added to a corn-soybean meal diet containing 0.43 g P/100 g (0.1 g nonphytate P/100 g). These responses were similar to those obtained from supplemental P (0.1 g/100 g) as KH2PO4 or from added 1,25-(OH)2D3 (10 micrograms/kg). Dietary addition of both 1200 units phytase and 10 micrograms/kg 1,25-(OH)2D3 elicited bone ash responses that were near 100%. When chicks were fed a Zn-deficient soy-concentrate diet (13 mg Zn/kg), diet supplementation with 1,25-(OH)2D3 or phytase increased growth rate by 40% and tibia Zn content by > 100%; adding 1,25-(OH)2D3 together with phytase increased tibia Zn content by 160%. Utilization of both Zn and Mn contained in the corn-soybean meal diet also was markedly enhanced by supplemental phytase, 1,25-(OH)2D3, or the combination. The cholecalciferol analog 1 alpha-OH D3 was found to improve dietary P utilization maximally (70% bone ash response) at a dose of 20 micrograms/kg diet, and effects were additive when 1 alpha-OH D3 was fed in the presence of phytase.(ABSTRACT TRUNCATED AT 250 WORDS)
authors.affiliation: Department of Animal Sciences, University of Illinois at Urbana-Champaign 61801, USA.
authors.forename: R R
authors.initials: RR
authors.lastname: Biehl
authors.forename: D H
authors.initials: DH
authors.lastname: Baker
authors.forename: H F
authors.initials: HF
authors.lastname: DeLuca
mesh_terms: D010832:6-Phytase / Q000008:administration & dosage / Q000494:pharmacology*; D000818:Animals; D002117:Calcitriol / Q000008:administration & dosage / Q000494:pharmacology; D002645:Chickens / Q000378:metabolism*; D004044:Dietary Proteins / Q000008:administration & dosage / Q000494:pharmacology; D004357:Drug Synergism; D005260:Female; D005527:Food, Fortified; D006887:Hydroxycholecalciferols / Q000008:administration & dosage / Q000494:pharmacology*; D006900:Hydroxylation; D007413:Intestinal Mucosa / Q000378:metabolism; D007422:Intestines / Q000502:physiology; D008099:Liver / Q000378:metabolism / Q000502:physiology; D008297:Male; D008345:Manganese / Q000378:metabolism*; D010758:Phosphorus / Q000378:metabolism* / Q000493:pharmacokinetics; D014674:Plant Proteins, Dietary / Q000008:administration & dosage / Q000494:pharmacology; D030262:Soybean Proteins; D013977:Tibia / Q000737:chemistry; D003313:Zea mays / Q000592:standards; D015032:Zinc / Q000032:analysis / Q000378:metabolism*
chemical_list: D004044:Dietary Proteins; D006887:Hydroxycholecalciferols; D014674:Plant Proteins, Dietary; D030262:Soybean Proteins; D010758:Phosphorus; D008345:Manganese; D010832:6-Phytase; D002117:Calcitriol; D015032:Zinc; C008088:alfacalcidol