Promoting the synchronization of glucose and amino acid release in the digestive tract of pigs could effectively improve dietary nitrogen utilization. The rational allocation of dietary starch sources and the exploration of appropriate dietary glucose release kinetics may promote the dynamic balance of dietary glucose and amino acid supplies. However, research on the effects of diets with different glucose release kinetic profiles on amino acid absorption and portal amino acid appearance in piglets is limited. This study aimed to investigate the effects of the kinetic pattern of dietary glucose release on nitrogen utilization, the portal amino acid profile, and nutrient transporter expression in intestinal enterocytes in piglets. Sixty-four barrows (15.00 ± 1.12 kg) were randomly allotted to 4 groups and fed diets formulated with starch from corn, corn/barley, corn/sorghum, or corn/cassava combinations (diets were coded A, B, C, or D respectively). Protein retention, the concentrations of portal amino acid and glucose, and the relative expression of amino acid and glucose transporter mRNAs were investigated. In vitro digestion was used to compare the dietary glucose release profiles. Four piglet diets with different glucose release kinetics were constructed by adjusting starch sources. The in vivo appearance dynamics of portal glucose were consistent with those of in vitro dietary glucose release kinetics. Total nitrogen excretion was reduced in the piglets in group B, while apparent nitrogen digestibility and nitrogen retention increased (P < 0.05). Regardless of the time (2 h or 4 h after morning feeding), the portal total free amino acids content and contents of some individual amino acids (Thr, Glu, Gly, Ala, and Ile) of the piglets in group B were significantly higher than those in groups A, C, and D (P < 0.05). Cluster analysis showed that different glucose release kinetic patterns resulted in different portal amino acid patterns in piglets, which decreased gradually with the extension of feeding time. The portal His/Phe, Pro/Glu, Leu/Val, Lys/Met, Tyr/Ile and Ala/Gly appeared higher similarity among the diet treatments. In the anterior jejunum, the glucose transporter SGLT1 was significantly positively correlated with the amino acid transporters B0AT1, EAAC1, and CAT1. Rational allocation of starch resources could regulate dietary glucose release kinetics. In the present study, group B (corn/barley) diet exhibited a better glucose release kinetic pattern than the other groups, which could affect the portal amino acid contents and patterns by regulating the expression of amino acid transporters in the small intestine, thereby promoting nitrogen deposition in the body, and improving the utilization efficiency of dietary nitrogen.

中文翻译：

---

日粮葡萄糖释放动力学模式对仔猪肠细胞氮利用、门静脉氨基酸谱和营养转运蛋白表达的影响

促进猪消化道葡萄糖和氨基酸同步释放，可有效提高日粮氮素利用率。膳食淀粉来源的合理配置和探索适当的膳食葡萄糖释放动力学可能会促进膳食葡萄糖和氨基酸供应的动态平衡。然而，关于不同葡萄糖释放动力学曲线的日粮对仔猪氨基酸吸收和门静脉氨基酸出现影响的研究有限。本研究旨在研究日粮葡萄糖释放的动力学模式对仔猪肠道细胞氮利用、门静脉氨基酸谱和营养转运蛋白表达的影响。64 只阉猪（15.00 ± 1.12 kg）被随机分配到 4 组，并饲喂由玉米、玉米/大麦、玉米/高粱或玉米/木薯组合制成的淀粉配制的日粮（日粮编码为 A、B、C 或 D）分别）。研究了蛋白质保留、门静脉氨基酸和葡萄糖的浓度以及氨基酸和葡萄糖转运蛋白mRNA的相对表达。使用体外消化来比较膳食葡萄糖释放曲线。通过调整淀粉来源构建了四种具有不同葡萄糖释放动力学的仔猪日粮。门静脉葡萄糖的体内表现动力学与体外膳食葡萄糖释放动力学一致。B组仔猪总氮排泄量减少，表观氮消化率和氮保留量增加（P < 0.05）。无论何种时间（早晨饲喂后2 h或4 h），B组仔猪门静脉总游离氨基酸含量和部分氨基酸（Thr、Glu、Gly、Ala、Ile）含量均显着较高高于 A、C、D 组（P < 0.05）。聚类分析表明，不同的葡萄糖释放动力学模式导致仔猪门静脉氨基酸模式不同，且随着饲喂时间的延长逐渐减少。His/Phe、Pro/Glu、Leu/Val、Lys/Met、Tyr/Ile 和 Ala/Gly 的门户在饮食治疗中表现出较高的相似性。在空肠前部，葡萄糖转运蛋白 SGLT1 与氨基酸转运蛋白 B0AT1、EAAC1 和 CAT1 呈显着正相关。淀粉资源的合理配置可以调节膳食葡萄糖释放动力学。在本研究中，B组（玉米/大麦）饮食表现出比其他组更好的葡萄糖释放动力学模式，这可能通过调节小肠氨基酸转运蛋白的表达来影响门静脉氨基酸含量和模式，从而促进体内氮沉积，提高膳食氮的利用效率。