Effects of Non-phytate Phosphorus and 1a-Hydroxycholecalciferol on Growth Performance, Bone Mineralization, and Carcass Traits of Broiler Chickens
Han, J. CMa, KWang, J. GChen, G. HZhang, J. LQu, H. XYan, Y. FCheng, Y. H
This study evaluated the effects of dietary non-phytate phosphorus (NPP) and 1a-hydroxycholecalciferol (1a-OH-D3) on the growth performance, bone mineralization, and carcass traits of 1- to 21-day-old broiler chickens. On the day of hatch, 600 male Ross 308 chicks were weighed and randomly assigned to 12 treatments, with five cages of 10 birds each. A 6 × 2 factorial arrangement was applied, consisting of 0.20%, 0.25%, 0.30%, 0.35%, 0.40%, or 0.45% NPP and 0 or 5 g/kg of 1a-OH-D3. The basal diet contained 0.52% calcium (Ca) and was not supplemented with vitamin D3. Dietary NPP levels significantly affected growth performance and tibia mineralization (except width) of broilers; by contrast, meat yield and organ relative weight were not influenced by NPP. The inclusion of 1a-OH-D3 improved growth performance, tibia mineralization, and carcass and breast yield, whereas it decreased the relative weights of the liver, heart, and kidney. A significant interaction between NPP and 1a-OH-D3 was observed for body weight gain (BWG), feed efficiency (FE), mortality, serum Ca and P levels, tibia breaking-strength, ash weight, and Ca content, as well as breast yield and heart relative weight. These results suggest that broilers fed with 5 g of 1a-OH-D3 per kg of diet obtain optimal growth performance and tibia mineralization when dietary NPP level was 0.30% and the analyzed Ca to NPP ratio was 1.97.(AU)
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