This study aimed to investigate the effect of feed intake levels on the development of intestinal morphology and epithelial cell differentiation in piglets. Sixty-four 35-d-old healthy weaned piglets ([Large White × Landrace] × Duroc) with an initial weight (6.93 ± 0.12 kg) were randomly divided into 4 groups (100%, 80%, 40%, and 20% feed intake) with 8 replicates of 2 pigs each. Samples were collected on days 3 and 7. The results revealed that with an increase in feed restriction degree and time, the body weight and organ index of piglets significantly decreased, and the villus height (VH) and crypt depth of the duodenum, jejunum, and ileum also decreased linearly (P < 0.05). After 3 d of feed restriction, jejunal ki67, endocrine cells, goblet cells, and villus endocrine/VH all decreased linearly, but the villus cup/VH ratio increased linearly, and the 40% and 20% were significantly higher than those of the 100% and 80% (P < 0.05). There was also a linear decrease in jejunal ki67, endocrine cells, goblet cells, and villous endocrine/VH in piglets fed 7 d of food restriction; however, the villus goblet cells/VH ratio in the 20% was significantly higher than that in the 40% group and was not different from that in the 80% (P < 0.05). During 3 d of feed restriction, the expression of jejunal differentiation marker genes showed a linear decreasing trend (P < 0.05) but increased linearly after 7 d of feed restriction. The expression levels of interleukin17 (IL-17) and IL-22 also increased linearly (P < 0.05). Kyoto Encyclopedia of Genes and Genomes and gene set enrichment analysis analyses indicated that the PPAR signaling pathway, ECM–receptor interaction, and Th1, Th2, and Th17 cell differentiation were significantly enriched in these processes. real-time quantitative polymerase chain reaction demonstrated that both PPAR and ECM–receptor interactions were significantly activated during 7 d of feeding restriction (P < 0.05). The results showed that with an increase in feed restriction intensity and time, the intestinal morphology and epithelial cell proliferation and differentiation were significantly reduced, except for the goblet cells. This phenomenon is related to the regulation of intestinal differentiation by IL-17 and IL-22 secreted by the Th cells.

中文翻译：

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不同采食量对仔猪肠道形态和上皮细胞分化的影响


本研究旨在探讨采食量水平对仔猪肠道形态发育和上皮细胞分化的影响。将初始体重（6.93 ± 0.12 kg）的 64 头 35 d 龄健康断奶仔猪（[大白×长白]×杜洛克）随机分为 4 组（采食量 100%、80%、40% 和 20%），每组 2 头猪 8 个重复。在第 3 天和第 7 天收集样本。结果显示，随着限食程度和时间的增加，仔猪体重和器官指数显著下降，十二指肠、空肠和回肠的绒毛高度 （VH） 和隐窝深度也呈线性下降 （P < 0.05）。限食 3 d 后，空肠 Ki67 、内分泌细胞、杯状细胞和绒毛内分泌/VH 均呈线性下降，但绒毛杯/VH 比值呈线性增加，40% 和 20% 均显著高于 100% 和 80% （P < 0.05）。限制进食 7 d 的仔猪空肠 ki67 、内分泌细胞、杯状细胞和绒毛内分泌/VH 也呈线性下降;然而，20% 组的绒毛杯状细胞/VH 比值显著高于 40% 组，与 80% 组无差异 （P < 0.05）。限食 3 d 后，空肠分化标志基因表达呈线性下降趋势 （P < 0.05），但减食 7 d 后线性增加。白细胞介素 17 （IL-17） 和 IL-22 的表达水平也呈线性升高 （P < 0.05）。京都基因与基因组百科全书和基因集富集分析分析表明，PPAR 信号通路、ECM-受体相互作用以及 Th1、Th2 和 Th17 细胞分化在这些过程中显著富集。 实时定量聚合酶链反应显示，在摄食限制 7 d 期间，PPAR 和 ECM-受体相互作用均被显著激活 （P < 0.05）。结果表明，随着饲喂限制强度和时间的增加，除杯状细胞外，肠道形态和上皮细胞增殖和分化均显著降低。这种现象与 Th 细胞分泌的 IL-17 和 IL-22 对肠道分化的调节有关。