Studies on the efficacy of cholecalciferol and derivatives for stimulating phytate utilization in broilers
2002
Edwards, H.M. Jr
Studies were conducted to determine the effect of dietary supplementation with cholecalciferol (D3), 1,25-dihydroxycholecalciferol [1,25-(OH)2D3], 1alpha-hydroxycholecalciferol (1alpha-OHD3), and 25-hydroxycholecalciferol (25-OHD3) on utilization of phytate P by broiler chickens. Three experiments were conducted with corn-soybean meal type diets with D3 and 1,25-(OH)2D3 being tested in one experiment and 1,25-(OH)2D3, 1alpha-OHD3, and 25-OHD3 being tested in two experiments of exactly the same design. In the first experiment, high levels of D3 (110 microgram and 220 microgram/kg of diet) increased phytate P utilization, but the increase was not as great as that obtained from 1,25-(OH)2D3 supplementation. In the other two experiments, 1,25-(OH)2D3, D3 and 1alpha-OHD3 were consistently effective in increasing phytate P utilization as measured by plasma Ca and P, incidence of P rickets, bone ash, and retention of Ca, P, and phytate P. Supplementation with 25-OHD3 in general gave smaller and more inconsistent responses to these criteria, indicating some inconsistency in its ability to improve phytate P utilization.
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