Protein releases amino acids faster than starch releases glucose in digestive tract of pigs fed low-protein (LP) diets. Poor synchronization of dietary glucose and amino acids supply leads to compromised nitrogen efficiency. Dietary starch patterns modulation may improve this situation. Growing barrows (29.7 ± 2.0 kg) were randomly allotted into 5 dietary treatments with LP diets consisting of different purified starches. Treatments included: waxy corn starch (W LP), corn starch + waxy corn starch (C + W LP), corn starch (C LP), pea starch + waxy corn starch (P + W LP) and pea starch (P LP). In the experiment, growth performance, protein deposition, nutrient metabolism, and fecal microbial community of pigs were investigated. In vitro starch digestion was used for predicting the in vivo glucose response. Dietary starch in vitro glucose release profile was determined by starch source and the ratio of amylopectin and amylose. C + W LP treatment showed decreased total nitrogen excretion and plasma citrulline concentration and improved plasma leptin concentration among treatments (P < 0.05). Besides, the highest nitrogen apparent biological value, whole-body protein deposition and growth performance and lowest urinary nitrogen excretion were also observed in C + W LP treatment. Compared with the other groups, C + W LP and C LP showed increased plasma pyruvate, IGF-1, and lipase concentrations (P < 0.05). The W LP group presented dramatically increased plasma alanine and urea nitrogen concentration and decreased aldolase and leptin concentrations (P < 0.05). Dietary starch patterns did not make an impact on bacterial richness and diversity, but changed the taxonomic and functional structures of the microbial communities. Microbial protein fermentation product (isobutyrate and isovalerate) presented increased in P LP treatments compared with the other treatments (P < 0.05). Dietary starch patterns modulation can regulate dietary glucose release profile, nutrient metabolism, protein turnover, and fecal microbial fermentation in pigs. The optimal dietary glucose release profile effectively strengthened whole-body protein deposition and improve nitrogen efficiency and growth performance in growing pigs fed LP diets.

中文翻译：

---

低蛋白日粮中不同的日粮淀粉模式：对生长猪氮效率、营养代谢和肠道菌群的影响

在饲喂低蛋白 (LP) 日粮的猪的消化道中，蛋白质释放氨基酸的速度快于淀粉释放葡萄糖的速度。膳食葡萄糖和氨基酸供应的不同步导致氮效率受损。膳食淀粉模式调制可能会改善这种情况。生长的手推车 (29.7 ± 2.0 kg) 被随机分配到 5 个日粮处理中，LP 日粮由不同的纯化淀粉组成。处理包括：糯玉米淀粉 (W LP)、玉米淀粉 + 糯玉米淀粉 (C + W LP)、玉米淀粉 (C LP)、豌豆淀粉 + 糯玉米淀粉 (P + W LP) 和豌豆淀粉 (P LP) . 在实验中，研究了猪的生长性能、蛋白质沉积、营养代谢和粪便微生物群落。体外淀粉消化用于预测体内葡萄糖反应。膳食淀粉体外葡萄糖释放曲线由淀粉源和支链淀粉与直链淀粉的比例决定。C + W LP处理显示总氮排泄和血浆瓜氨酸浓度降低，血浆瘦素浓度提高（P <0.05）。此外，在C+W LP处理中也观察到最高的氮表观生物学值、全身蛋白质沉积和生长性能以及最低的尿氮排泄。与其他组相比，C+W LP 和 C LP 血浆丙酮酸、IGF-1 和脂肪酶浓度升高（P < 0.05）。W LP 组血浆丙氨酸和尿素氮浓度显着增加，醛缩酶和瘦素浓度降低（P < 0.05）。膳食淀粉模式不会影响细菌的丰富度和多样性，但改变了微生物群落的分类和功能结构。与其他处理相比，P LP 处理的微生物蛋白质发酵产物（异丁酸和异戊酸）增加（P < 0.05）。日粮淀粉模式调节可以调节猪的日粮葡萄糖释放曲线、营养代谢、蛋白质周转和粪便微生物发酵。优化的日粮葡萄糖释放曲线有效地增强了饲喂 LP 日粮的生长猪的全身蛋白质沉积，提高了氮效率和生长性能。日粮淀粉模式调节可以调节猪的日粮葡萄糖释放曲线、营养代谢、蛋白质周转和粪便微生物发酵。优化的日粮葡萄糖释放曲线有效地增强了饲喂 LP 日粮的生长猪的全身蛋白质沉积，提高了氮效率和生长性能。日粮淀粉模式调节可以调节猪的日粮葡萄糖释放曲线、营养代谢、蛋白质周转和粪便微生物发酵。优化的日粮葡萄糖释放曲线有效地增强了饲喂 LP 日粮的生长猪的全身蛋白质沉积，提高了氮效率和生长性能。