Effects of 1,25-dihydroxycholecalciferol and phytase on zinc utilization in broiler chicks

• Published in: Poultry science 1994-08, Vol.73 (8), p.1312-1326
• Main Authors: Roberson, K.D, Edwards, H.M. Jr
• Format: Article
• Language: English
• Subjects: 6-Phytase - administration & dosage; ABSORCION; ABSORPTION; ACIDE PHYTIQUE; ACIDO FITICO; ACTIVIDAD ENZIMATICA; ACTIVITE ENZYMATIQUE; Animals; Body Weight - drug effects; Bone Density - drug effects; CALCIO; Calcitriol - administration & dosage; CALCIUM; Chickens - metabolism; CINC; ENFERMEDADES OSEAS; FITASA; Food, Fortified; FOSFATASA ALCALINA; FOSFORO; HUESOS DE LOS MIEMBROS; Incidence; Male; METABOLISME DES MINERAUX; METABOLISMO DE MINERALES; OS DES MEMBRES; Osteochondrodysplasias - epidemiology; Osteochondrodysplasias - veterinary; OSTEOPATHIE; PESO; PHOSPHATASE ALCALINE; PHOSPHORE; Phosphorus - metabolism; PHYTASE; POIDS; POLLITO; POLLO DE ENGORDE; POULET DE CHAIR; Poultry Diseases - epidemiology; POUSSIN; SERUM SANGUIN; SUERO SANGUINEO; Tibia; VITAMINA D; VITAMINE D; ZINC; Zinc - administration & dosage; Zinc - metabolism
• ISSN: 0032-5791; 1525-3171
• DOI: 10.3382/ps.0731312

Studies were conducted with corn-soybean meal diets to evaluate the effects of phytate phosphorus utilization on zinc absorption and retention in broiler chicks. In the first two experiments, zinc-65 was used to determine zinc absorption. Experiment 1 was a 2 X 2 factorial with 0 or 5 microgram/kg dihydroxycholecalciferol and 0 or 40 ppm supplemental zinc. In Experiment 2, 5 microgram/kg 1,25-dihydroxycholecalciferol [1,25-(OH)2D3] or 750 units/kg phytase or both were added to a diet containing 35 ppm zinc. The diets in Experiment 3 were similar to Experiment 2 except that 600 units/kg phytase was fed. Experiment 4 was similar to Experiment 3 except that dietary phosphorus was decreased by 0.15%. There were no treatment effects on body weight in Experiments 1 and 2. Zinc absorption was higher in zinc-deficient birds in Experiment 1, but there were no other effects on zinc-65 absorption or retention. Body weight was increased by 1,25-(OH)2D3 in Experiments 3 and 4 and by phytase in Experiment 4. Phytate phosphorus retention was increased by phytase and 1,25-(OH)2D3 and was increased additively when both sources were fed. Dietary 1,25-(OH)2D3 increased zinc retention at times during Experiments 3 and 4, but this response was inconsistent. Phytase did not affect zinc retention. Phytase plus 1,25-(OH)2D3 increased zinc retention synergistically in Experiment 3. Bone zinc was increased by 1,25-(OH)2D3 and phytase, and there was an additive effect in Experiment 3. Plasma zinc and alkaline phosphatase were not affected. The results suggest that supplemental zinc may be decreased in a corn-soybean meal diet when phytate phosphorus utilization is enhanced