A 20-d experiment was conducted to test the hypothesis that phytase increases nutrient digestibility, bone ash, and growth performance of pigs fed diets containing 0.23%, 0.29%, or 0.35% phytate-bound P. Within each level of phytate, five diets were formulated to contain 0, 500, 1,000, 2,000, or 4,000 phytase units (FTU)/kg of a novel phytase (PhyG). Three reference diets were formulated by adding a commercial Buttiauxella phytase (PhyB) at 1,000 FTU/kg to diets containing 0.23%, 0.29%, or 0.35% phytate-bound P. A randomized complete block design with 144 individually housed pigs (12.70 ± 4.01 kg), 18 diets, and 8 replicate pigs per diet was used. Pigs were adapted to diets for 15 d followed by 4 d of fecal collection. Femurs were collected on the last day of the experiment. Results indicated that diets containing 0.35% phytate-bound P had reduced (P < 0.01) digestibility of Ca, P, Mg, and K compared with diets containing less phytate-bound P. Due to increased concentration of total P in diets with high phytate, apparent total tract digestible P and bone ash were increased by PhyG to a greater extent in diets with 0.29% or 0.35% phytate-bound P than in diets with 0.23% phytate-bound P (interaction, P < 0.05). At 1,000 FTU/kg, PhyG increased P digestibility and bone P more (P < 0.05) than PhyB. The PhyG increased (P < 0.01) pig growth performance, and pigs fed diets containing 0.35% or 0.29% phytate-bound P performed better (P < 0.01) than pigs fed the 0.23% phytate-bound P diets. In conclusion, the novel phytase (i.e., PhyG) is effective in increasing bone ash, mineral digestibility, and growth performance of pigs regardless of dietary phytate level.

中文翻译：

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一种新型共有细菌 6-植酸酶变体对饲喂不同浓度植酸结合磷日粮的幼猪的矿物质消化率和骨灰分的影响

进行了一项为期 20 天的实验，以检验植酸酶可提高饲喂含 0.23%、0.29% 或 0.35% 植酸结合磷日粮的猪的养分消化率、骨灰分和生长性能的假设。在每个植酸水平内，五种日粮配制成含有 0、500、1,000、2,000 或 4,000 个植酸酶单位 (FTU)/kg 的新型植酸酶 (PhyG)。三种参考日粮通过在含有 0.23%、0.29% 或 0.35% 植酸结合 P 的日粮中添加 1,000 FTU/kg 的商品化布蒂奥氏菌植酸酶 (PhyB) 配制而成。 144 头单独饲养的猪的随机完整区组设计 (12.70 ± 4.01 kg)、18 种日粮，每种日粮使用 8 头重复猪。猪适应饮食 15 天，然后收集粪便 4 天。在实验的最后一天收集股骨。结果表明日粮中含有 0。与含有较少植酸磷的日粮相比，35% 植酸磷降低了 (P < 0.01) 钙、磷、镁和钾的消化率。在 0.29% 或 0.35% 植酸结合 P 的日粮中，PhyG 对可消化磷和骨灰的增加程度比在 0.23% 植酸结合 P 的日粮中更大（相互作用，P < 0.05）。在 1,000 FTU/kg 时，PhyG 比 PhyB 增加了更多的磷消化率和骨磷（P < 0.05）。PhyG 提高了（P < 0.01）猪的生长性能，饲喂含 0.35% 或 0.29% 植酸结合 P 日粮的猪比饲喂 0.23% 植酸结合 P 日粮的猪表现更好（P < 0.01）。总之，新型植酸酶（即 PhyG）可有效增加骨灰分、矿物质消化率、