An experiment was conducted to determine the standardized ileal digestible (SID) calcium requirement of fast-growing broilers from hatch to d 14 post-hatch. Ross 308 ( = 360) male broilers were obtained on day of hatch and allocated to 1 of 5 treatments in battery cages. There were 6 birds per cage and 12 pens per treatment. Four treatments were formulated to contain 0.60%, 0.46%, 0.32% or 0.18% SID Ca. The final treatment was formulated using total Ca to meet or exceed all nutrient requirements, including 0.90% total Ca and 0.49% non-phytate P (nPP), using the same ingredients. This treatment was the reference diet for comparison and validation of the SID Ca diets. Birds and feed were weighed at placement and on d 14. Tibias and ileal contents were obtained on d 14 and excreta was collected per pen and pooled on d 14. Data were analyzed using JMP Pro and requirements were estimated using 3 different non-linear regression models. Increasing the SID Ca content in the diet from 0.18% to 0.60% improved (quadratic, 0.05) body weight gain and mortality corrected feed conversion ratio (mFCR). The estimated SID Ca requirement to optimize gain or mFCR was between 0.39% and 0.52%. Tibia ash percent and weight increased (quadratic, < 0.05) as SID Ca content in the diet increased and the estimated SID Ca requirement was between 0.32% and 0.58%. Phosphorus utilization was improved in birds fed diets formulated using SID Ca compared with birds fed the reference diet. In conclusion, the SID Ca requirement of fast-growing broilers from hatch to d 14 was estimated between 0.534% and 0.398% when quadratic, straight-broken line, or quadratic-broken line regressions were used. These results agree with previously published data evaluating the SID Ca requirement of fast-growth broilers from hatch to d 10.

中文翻译：

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测定罗斯肉鸡从孵化到孵化后第 14 天的标准化回肠可消化钙需求量

进行了一项实验以确定快速生长的肉鸡从孵化到孵化后第 14 天的标准化回肠可消化 (SID) 钙需求量。孵化当天获得 308 (= 360) 只罗斯雄性肉鸡，并在笼式笼中分配到 5 组处理中的 1 组。每个处理有 12 个围栏，每个笼子有 6 只鸟。四种处理配制为含有 0.60%、0.46%、0.32% 或 0.18% SID Ca。最终处理采用总钙配制，以满足或超过所有营养需求，包括 0.90% 总钙和 0.49% 非肌醇六磷酸 P (nPP)，使用相同的成分。该治疗是用于比较和验证 SID Ca 饮食的参考饮食。在放置时和第 14 天对家禽和饲料进行称重。在第 14 天获得胫骨和回肠内容物，并在第 14 天收集每栏的排泄物并在第 14 天汇集。使用 JMP Pro 分析数据，并使用 3 种不同的非线性回归估计需求量楷模。将日粮中的 SID Ca 含量从 0.18% 增加到 0.60% 可以改善（二次，0.05）体重增加和死亡率校正饲料转化率 (mFCR)。优化增益或 mFCR 所需的 SID Ca 估计值在 0.39% 至 0.52% 之间。随着饮食中 SID Ca 含量的增加，胫骨灰分和重量增加（二次方，< 0.05），并且估计的 SID Ca 需求量在 0.32% 至 0.58% 之间。与饲喂参考日粮的禽类相比，饲喂使用 SID Ca 配制的日粮的禽类的磷利用率得到了提高。总之，当使用二次、直折线或二次折线回归时，快速生长的肉鸡从孵化到第 14 天的 SID Ca 需求量估计在 0.534% 到 0.398% 之间。这些结果与之前发布的评估快速生长肉鸡从孵化到 10 天的 SID Ca 需求的数据一致。