The objective of this experiment was to investigate the effects of various dietary concentrations of vitamin D3 (D3) on pullet and laying hen performance, eggshell quality, bone health, and yolk D3 content from day of hatch until 68 wk of age. Initially, 440 Hy-line W36-day-old chicks were randomly assigned to 5 dietary treatments: 1,681 (control); 8,348; 18,348; 35,014; 68,348 IU D3/kg. At 17 wk of age, pullets were assigned to experimental diets with 12 replicate groups of 6 birds. At 17 wk of age, pullets fed diets containing 8,348 and 35,014 IU D3/kg had an increased bone mineral density in comparison to the control fed birds (P ≤ 0.01). Body weights of pullets fed the diet with 68,348 IU D3/kg were lower than other treatments (P ≤ 0.01). Hen-housed egg production (HHEP) of hens fed the 35,014 IU D3/kg diet was increased in comparison to control-fed hens (P ≤ 0.01), whereas HHEP of those fed 68,348 IU D3/kg diet was reduced in comparison to all other treatments (P ≤ 0.01). Shell breaking strength of eggs from hens fed 8,348, 35,014 and 68,348 IU D3/kg was increased in comparison to eggs from control-fed birds (P ≤ 0.01). Fat-free tibia ash content of hens fed any of the diets supplemented with D3 (8,348 to 68,348 IU D3/kg) was increased in comparison to control-fed hens (P ≤ 0.05). Yolk D3 content increased linearly with dietary D3 and the D3 transfer efficiency for the control, 8,348 IU, 18,348 IU, 35,014 IU, and 68,348 IU D3 treatments were 8.24, 10.29, 11.27, 12.42, and 12.06%, respectively. These data suggest that supplementation of dietary D3 up to 35,014 IU D3/kg feed maintained if not increased laying hen performance and enhanced pullet and laying hen skeletal quality as well as yolk D3 content and eggshell quality. Feeding pullets at a higher level 68,348 IU of D3 resulted in reduced growth and ultimately decreased performance of laying hens.

中文翻译：

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从孵化当天到 68 周龄饲喂 W36 蛋鸡时，高浓度日粮维生素 D3 对小母鸡和蛋鸡的生产性能、骨骼健康、蛋壳质量和蛋黄维生素 D3 含量的影响。

本实验的目的是研究不同日粮浓度的维生素 D3 (D3) 对雏鸡和蛋鸡的生产性能、蛋壳质量、骨骼健康以及从孵化当天到 68 周龄的蛋黄 D3 含量的影响。最初，440 只 Hy-line W36 日龄小鸡被随机分配到 5 种饮食治疗中：1,681 只（对照）；8,348; 18,348; 35,014; 68,348 国际单位 D3/公斤。在 17 周龄时，小母鸡被分配到实验日粮，12 个重复组，每组 6 只鸡。在 17 周龄时，与对照组相比，饲喂 8,348 和 35,014 IU D3/kg 日粮的小母鸡骨矿物质密度增加（P ≤ 0.01）。饲喂 68,348 IU D3/kg 日粮的小母鸡体重低于其他处理（P ≤ 0.01）。饲养 35 只的母鸡的鸡舍产蛋量 (HHEP)，与对照组相比，饲喂 014 IU D3/kg 日粮的母鸡增加了（P ≤ 0.01），而饲喂 68,348 IU D3/kg 日粮的母鸡的 HHEP 与所有其他处理相比降低了（P ≤ 0.01）。与对照饲喂鸡的蛋相比，饲喂 8,348、35,014 和 68,348 IU D3/kg 的母鸡蛋的破壳强度增加（P ≤ 0.01）。与对照组相比，饲喂任何添加 D3 的日粮（8,348 至 68,348 IU D3/kg）的母鸡的脱脂胫骨灰分含量均有所增加（P ≤ 0.05）。蛋黄 D3 含量随日粮 D3 呈线性增加，对照组、8,348 IU、18,348 IU、35,014 IU 和 68,348 IU D3 处理的 D3 转移效率分别为 8.24%、10.29%、11.27%、12.42% 和 12.06%。这些数据表明，膳食 D3 的补充高达 35，014 IU D3/kg 饲料保持不变，如果不提高蛋鸡生产性能和提高后备母鸡和蛋鸡骨骼质量以及蛋黄 D3 含量和蛋壳质量。以较高水平的 68,348 IU D3 饲喂后备母鸡会导致生长速度下降，并最终降低蛋鸡的生产性能。