An experiment was conducted to investigate the effects of particle size (PS) and levels of phytase supplementation on the apparent (ATTD) and standardized (STTD) total tract digestibility of P in hybrid rye fed to growing pigs. Thirty-six growing barrows (23.6 ± 1.5 kg initial BW) were individually housed in metabolism crates and randomly allotted to one of six dietary treatments to give six replicates per treatment. The six dietary treatments were arranged in a 2 × 3 factorial with main effects of PS and phytase supplementation levels (0, 500, or 2,500 FTU/kg). Hybrid rye was ground using a hammermill mounted with 4.0-mm and 3.2-mm screens to obtain material with coarse and fine PS, respectively. Pigs were fed experimental diets for 11 d, including 5 d for adaptation and 6 d for total collection of feces. All data were analyzed using the MIXED procedure of SAS with PS, phytase, and their interaction as fixed effects. Orthogonal polynomial contrasts were used to test linear and quadratic effects of phytase level in both coarse and fine hybrid rye diets. The ATTD and STTD of P were greater (P < 0.05) in diets with fine than in those with coarse hybrid rye. Increasing levels of phytase supplementation linearly (P < 0.01) and quadratically (P < 0.01) improved the ATTD and STTD of P in hybrid rye diets. There were no interaction effects between PS and phytase supplementation on the ATTD and STTD of P in hybrid rye diets. In conclusion, PS reduction improved the digestibility of P in hybrid rye, and supplementing increasing levels of phytase improved P digestibility in linear and quadratic manner in growing pigs fed hybrid rye diets.

中文翻译：

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颗粒大小和植酸酶添加量对生长猪饲喂的杂交黑麦中磷的表观和标准化总消化道消化率的影响

进行了一项实验，研究粒径 (PS) 和植酸酶补充水平对饲喂生长猪的杂交黑麦中磷的表观 (ATTD) 和标准化 (STTD) 总消化道消化率的影响。将 36 头生长中的公猪（初始体重 23.6 ± 1.5 千克）单独饲养在代谢箱中，并随机分配到六种饮食处理中的一种，每个处理重复六次。六种饮食治疗以 2 × 3 因子排列，主要影响 PS 和植酸酶补充水平（0、500 或 2,500 FTU/kg）。使用安装有 4.0 毫米和 3.2 毫米筛网的锤磨机研磨杂交黑麦，分别获得具有粗 PS 和细 PS 的材料。给猪饲喂实验饲料11天，其中5天用于适应，6天用于收集粪便。所有数据均使用 SAS 与 PS、植酸酶的混合程序进行分析，并将它们的相互作用作为固定效应。使用正交多项式对比来测试粗粒和细粒混合黑麦日粮中植酸酶水平的线性和二次效应。细粒杂麦日粮中 P 的 ATTD 和 STTD 高于粗粒杂交黑麦日粮中的 (P < 0.05)。线性（P < 0.01）和二次（P < 0.01）增加植酸酶补充水平可改善杂交黑麦日粮中 P 的 ATTD 和 STTD。PS 和植酸酶补充对混合黑麦日粮中 P 的 ATTD 和 STTD 没有相互作用。总之，PS 的减少提高了杂交黑麦中磷的消化率，而补充增加植酸酶水平则以线性和二次方的方式提高了饲喂混合黑麦日粮的生长猪的磷消化率。