Effect of dietary calcium and vitamin D3 on calcium and phosphorus retention in white Pekin ducklings.
Higher concentrations of Ca in the diet may decrease phytate-phosphorus hydrolysis because of chelation of Ca with the phytin molecule. In experiment 1, drakes were fed 0.74, 0.85, 0.95, or 1.11% Ca (analyzed) from 7 to 18 d of age (6 birds/cage, 8 cages/diet). Intestinal mucosa was collected at 18 d of age from birds fed 0.74 and 1.11% Ca for determination of intestinal phytase activity. In experiment 1, 17 d BW gain and feed consumption exhibited a quadratic response to increasing concentrations of Ca and were found to be maximal for ducks fed the 0.95% Ca diet. Toe ash percentage (18 d) had a quadratic response to increasing concentrations of Ca with a maximal response for birds fed the 0.85% Ca diet. Increasing dietary Ca did not affect P retention from 15 to 17 d of age or intestinal phytase activity and brush border vesicle Ca concentration. A positive correlation was found between the Vmax and the Ca concentration within the vesicles (r = 0.59, P < 0.02), suggesting that the vesicle Ca concentration did not negatively affect the kinetics of the phytase assay. In experiment 2, drakes were fed 0.6, 0.8, 1.0, or 1.2% Ca (formulated) with 826 or 8,260 ICU/kg of vitamin D3 from 0 to 13 d of age. There was no response to increasing concentrations of Ca for performance characteristics or bone ash measurements.
Rush
J K
JK
Department of Animal Sciences, Purdue University, West Lafayette, Indiana 47907-1151, USA.
Angel
C R
CR
Banks
K M
KM
Thompson
K L
KL
Applegate
T J
TJ
D010832:6-Phytase / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D001842:Bone and Bones / Q000187:drug effects / Q000378:metabolism; D002118:Calcium / Q000378:metabolism*; D002136:Calcium, Dietary / Q000494:pharmacology*; D002762:Cholecalciferol / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004372:Ducks / Q000378:metabolism*; D007421:Intestine, Small / Q000201:enzymology; D008297:Male; D010758:Phosphorus / Q000378:metabolism*
D002136:Calcium, Dietary; D002762:Cholecalciferol; D010758:Phosphorus; D010832:6-Phytase; D002118:Calcium