25羟基维生素D_3和1α羟基维生素D_3代替维生素D_3对42～63日龄黄羽肉鸡生长性能、血清生化指标和胫骨发育的影响

25-OH-D_3 and 1α-OH-D_3 Replacing Vitamin D_3:Effects on Growth Performance,Serum Biochemical Indices and Tibia Development of Yellow-Feathered Broilers Aged from 42 to 63 Days

本试验旨在研究饲粮中添加25羟基维生素D3(25-OH-D3)和1α羟基维生素D3(1α-OH-D3)代替维生素D3对42～63日龄黄羽肉鸡生长性能、血清生化指标、胫骨发育和养分消化率的影响。试验选用42日龄黄羽肉公鸡2 400只,随机分成8个处理,每个处理5个重复,每个重复60只鸡。处理1(正常钙磷饲粮对照组)的维生素D3、钙、磷含量分别为2 780 IU/kg、0.8%、0.55%;处理2(低钙磷饲粮对照组)～8的维生素D3、钙、磷含量分别为0 IU/kg、0.7%、0.45%;处理3～5中25-OH-D3的添加水平分别为50、70、90μg/kg,处理6～8中1α-OH-D3的添加水平分别为2.5、5.0、10.0μg/kg。试验期21 d。结果表明:1)与低钙磷饲粮对照组相比,除添加50μg/kg 25-OH-D3未使黄羽肉鸡平均日采食量(ADFI)有显著变化(P>0.05)外,添加不同水平的25-OH-D3或10.0μg/kg 1α-OH-D3均可显著提高黄羽肉鸡生长性能(P<0.05),添加70、90μg/kg 25-OH-D3或2.5、5.0、10.0μg/kg 1α-OH-D3均可显著提高钙表观消化率和真消化率(P<0.05),添加5.0、10.0μg/kg 1α-OH-D3可显著提高磷表观消化率和真消化率(P<0.05);添加50、70、90μg/kg 25-OH-D3或10.0μg/kg 1α-OH-D3均可显著提高血清磷含量和显著降低血清钙磷比(P<0.05),添加90μg/kg 25-OH-D3或10.0μg/kg 1α-OH-D3还可显著降低血清抗酒石酸酸性磷酸酶(TRAP)活性(P<0.05),但各处理血清碱性磷酸酶(ALP)活性差异不显著(P>0.05);添加90μg/kg 25-OH-D3或10.0μg/kg 1α-OH-D3可显著提高胫骨粗灰分重、钙磷比、鲜重、脱脂重、脱脂重指数、长度、折断力和骨密度(P<0.05),但对胫骨粗灰分率、钙含量和鲜重指数均没有显著影响(P>0.05)。2)与正常钙磷饲粮对照组相比,添加70、90μg/kg 25-OH-D3或2.5、5.0、10.0μg/kg 1α-OH-D3均可显著提高钙表观消化率(P<0.05),添加10.0μg/kg 1α-OH-D3可显著提高磷表观消化率和真消化率(P<0.05);添加10.0μg/kg 1α-OH-D3或90μg/kg 25-OH-D3可显著提高血清磷含量和钙磷比(P<0.05),显著降低胫骨矿化度(P<0.05),但对生长性能、血清TRAP和ALP活性及除了矿化度和粗灰分重以外的所有胫骨发育指标均无显著影响(P>0.05)。结果提示,降低饲粮钙磷水平后,饲粮中添加25-OH-D3或1α-OH-D3能够有效代替维生素D3,可提高钙、磷消化率,对生长性能、胫骨发育有一定的改善趋势,其中90μg/kg 25-OH-D3和10.0μg/kg 1α-OH-D3获得的效果最佳。

This study was conducted to investigate the effects of 25-OH-D3 and 1 ct-OH-D3 replacing vitamin D3 on growth performance, serum biochemical indices, tibia development and nutrient digestibility of yellow-feathered broilers aged from 42 to 63 days. A total of 2 400 male yellow-feathered broilers aged 42 days were randomly divided into 8 groups with 5 replicates per group and 60 chickens in each replicate. Treatment 1 （control group ） was fed a basal diet, in which the contents of vitamin D3, calcium, phosphorus were 2 780 IU/kg, 0.8%, and 0. 55%, respectively. For treatments 2 （low phosphorus and calcium control group） to 8, the contents of vitamin Da, calcium, phosphorus were 0 IU/kg, 0.7%, 0.45%, respectively. For treatments 3 to 5, the contents of 25-OH-Da were 50, 70 and 90 μg/kg, respectively. For treatments 6 to 8, the contents of 1a-OH-Da were 2.5, 5.0 and 10.0 μg/kg, respectively. The experiment lasted for 21 days. The results showed as follows： 1 ） compared with low calcium and phosphorus control group, except that 50 μg/kg 25-OH-D3 did not affect average daily feed intake （ P 〉 0.05 ）, the supplementation of different levels of 25-OH-D3 or 10.0 μg/kg 1 a-OH-D3 significantly improved the growth performance of yellow-feath- ered broilers （P 〈 0.05） ; the supplementation of 70 and 90 μg/kg 25-OH-Da or 2.5, 5.0 and 10.0 μg/kg 1 a-OH-Da significantly improved calcium apparent and true digestibility （ P 〈 0.05 ）, and the supplementation of 5.0 and 10.0μg/kg 1a-OH-D3 significantly improved phosphorus apparent and true digestibility （P 〈 0.05 ） ; the supplementation of 50, 70 and 90 μg/kg 25-OH-D3 or 10.0 μg/kg 1a-OH-D3 significantly im- proved serum phosphorus content and decreased serum the ratio of calcium to phosphorus （Ca/P） （ P 〈 0.05 ）, and the supplementation of 90 μg/kg 25-OH-Da or 10.0 μg/kg 1a-OH-D3 significantly decreased ser- um tartrate resistant acid phosphatase （TRAP） activity （P 〈0.05）, while there was no significant difference in serum alkaline phosphatase （ALP） activity of yellow-feathered broilers among all treatments （P 〉 0.05 ） ; the supplementation of 90 μg/kg 25-OH-D3 or 10.0 μg/kg 1a-OH-D3 significantly improved ash weight, Ca/ P, fresh weight, defatted weigh, defatted weigh index, length, broken strength and bone density of tibia （ P 〈 0.05 ）, but had no influence on ash ratio, calcium content and fresh weight index of tibia （ P 〉 0.05 ）. 2 ） Compared with the normal calcium and phosphorus control group, the supplementation of 70 and 90 μg/kg 25-OH-D3 and 2. 5, 5.0 and 10.0 μg/kg la-OH-D3 significantly increased calcium apparent digestibility （P 〈 0.05 ）, and the supplementation of 10.0 μg/kg l ot-OH-D significantly increased phosphorus apparent and true digestibility （P 〈 0.05 ） ; the supplementation of 90 μg/kg 2S-OH-D3 or 10.0 ixg/kg 1 a-OH-D3 sig- nificantly increased serum phosphorus content and Ca/P （ P 〈 0.05 ）, and decreased tibia mineralization （ P 〈 0.05 ）, but had no significant effects on growth performance, serum TRAP and ALP activities and tibia devel- opment indices expect for mineralization and ash weight of yellow-feathered broilers （ P 〉 0.05 ）. These results indicate that reducing calcium and phosphate levels in diets and adding 25-OH-D3 or 1 a-OH-D3 replacing vita- min D3 can effectively improve the digestibility of phosphorus and calcium, growth performance and tibia de- velopment of yellow-feathered broilers. Of all the treatments, the addition of 90 /xg/kg 25-OH-Da or 10.0 μg/kg 1 a-OH-D3 has the best results in yellow-feathered broilers. [ Chinese Journal of Animal Nutri- tion, 2013, 25 （8） ： 1752-1761 ]