Effect of source and level of vitamin D on live performance and bone development in growing broilers
Effect of source and level of vitamin D on live performance and bone development in growing broilers
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DOI：
10.1093/japr/12.1.45
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发表时间：
2003-03-01
影响因子：
1.9
通讯作者：
Waldroup, PW
中科院分区：
文献类型：
--
作者：
Fritts, CA;Waldroup, PW
在营养齐全的玉米-豆粕日粮中，分别使用胆钙醇(Vit-D3)和25-羟基胆钙醇(25-OH-D3)提供125、250、500、1,000、2,000或4,000 Lu/kg的维生素D活性。每个处理被分配到四个围栏，每组60只雄性肉鸡(Cobb 500只)，饲养在一个有侧帘的开放式房子里。在21日龄和42日龄，测定体重和饲料转化率。8只鸡在相同日龄处死，取右侧胫骨进行骨灰测定，测定左侧胫骨软骨发育不良(TD)的发生率和严重程度。在第21天和42天，饲喂25-OH-D3组的体重显著高于饲喂维生素D3组。在第21天，无论来源如何，维生素D超过500IU/kg似乎都是最大化体重所必需的。在42日龄时，饲喂维生素D3的雏鸡需要大约1000IU/kg的体重才能使体重最大化，而饲喂不同水平的25-OH-D3的雏鸡的体重没有显著差异。与饲喂维生素D3的雏鸡相比，饲喂25-OH-D3的雏鸟在第21和42日龄时的骨灰显著增加。最大骨灰所需维生素D3约为2,000 IU/kg，而饲喂250~4,000 IU/kg饲料的雏鸡骨灰含量与25-OH-D3无显著差异。饲喂25-OH-D3的雏鸡TD的发生率和严重程度明显较低，并且无论来源如何，增加维生素D水平都会降低TD的发生率和严重程度。研究结果表明，25-羟基-D3的代谢能力更强。在单位基础上，比VIT-D3支持体重、胫骨灰分，并减少TD的发生率和严重程度。这些差异主要是在较低的维生素D水平上观察到的；在典型的行业水平上，两种来源之间的差异很小。使用25-羟基-D3可允许补充较低水平或可提供较大的安全边际。
Cholecalciferol (VIT-D3) and 25-hydroxycholecalciferol (25-OH-D3) were each used to provide 125, 250, 500, 1,000, 2,000, or 4,000 lU/kg of vitamin D activity in a nutritionally complete corn-soybean meal diet. Each treatment was assigned to four pens of 60 male broilers (Cobb 500) grown in an open-sided house with sidewall curtains. At 21 and 42 d, BW and feed conversion were determined. Samples of birds (8 per pen) were killed at the same ages; the right tibia was subjected to bone ash determination, and incidence and severity of tibial dyschondroplasia (TD) were determined on the left tibia.At 21 and 42 d, the BW of birds fed the 25-OH-D3 were significantly greater than those of birds fed the VIT-D3. At 21 d, vitamin D in excess of 500 IU/kg appeared necessary to maximize BW regardless of source. At 42 d, approximately 1,000 IU/kg was needed to maximize BW of birds fed VIT-D3, whereas no significant difference in BW was noted among birds fed the various levels of 25-OH-D3. Bone ash at 21 and 42 d was significantly greater for birds fed the 25-OH-D3 as compared to those fed the VIT-D3. Approximately 2,000 IU/kg of VIT-D3 was needed for maximum bone ash, whereas there were no significant differences in bone ash content of birds fed from 250 to 4,000 IU/kg from 25-OH-D3. The incidence and severity of TD was significantly lower for birds fed 25-OH-D3 and was reduced by increasing levels of vitamin D regardless of source. Results of the study show that 25-OH-D3 is more metabolically potent. on a per unit basis than VIT-D3 for support of BW, tibia ash, and reduction in incidence and severity of TD. The differences were observed primarily at lower levels of vitamin D; at typical industry levels, few differences were observed between the two sources. Use of the 25-OH-D3 may allow for supplementation with lower levels or may provide a greater margin of safety.