Modern hyperprolific sows must deal with large litters (16-20 piglets) which reduce piglet birthweight with a concomitant increase in the proportion of small and intrauterine growth retarded piglets. However, larger litters do not only have a greater variation of piglet weights, but also a greater variation in colostrum and milk consumption within the litter. To further understand the impact that body weight has on piglets, the present study aimed to evaluate the degree of physiological weakness of the smallest piglets at birth and during the suckling period (20 d) compared to their middle-weight littermates through their jejunal gene expression. At birth, light piglets showed a downregulation of genes related to immune response (FAXDC2, HSPB1, PPARGC1α), antioxidant enzymes (SOD2m), digestive enzymes (ANPEP, IDO1, SI), and nutrient transporter (SLC39A4) (P < 0.05) but also a tendency for a higher mRNA expression of GBP1 (inflammatory regulator) and HSD11β1 (stress hormone) genes compared to their heavier littermates (P < 0.10). Excluding HSD11β1 gene, all these intestinal gene expression differences initially observed at birth between light and middle-weight piglets were stabilized at the end of the suckling period, when others appeared. Genes involved in barrier function (CLDN1), pro-inflammatory response (CXCL2, IL6, IDO1) and stress hormone signaling (HSD11β1) over-expressed compared to their middle-weight littermates (P < 0.05). In conclusion, at birth and at the end of suckling period, light body weight piglets seem to have a compromised gene expression and therefore impaired nutrient absorption, immune and stress responses compared to their heavier littermates.

中文翻译：

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简短交流：新生和哺乳仔猪的体重影响它们的肠道基因表达

现代高产母猪必须处理大窝仔猪（16-20 头仔猪），这会降低仔猪出生体重，同时增加小猪和宫内生长迟缓仔猪的比例。然而，更大的窝不仅仔猪体重的变化更大，而且窝内的初乳和牛奶消耗量的变化也更大。为了进一步了解体重对仔猪的影响，本研究旨在通过空肠基因表达评估最小仔猪在出生时和哺乳期（20 天）与中等体重同窝仔猪的生理虚弱程度。 . 出生时，轻型仔猪表现出与免疫反应相关的基因（FAXDC2、HSPB1、PPARGC1α）、抗氧化酶（SOD2m）、消化酶（ANPEP、IDO1、SI）、和营养转运蛋白（SLC39A4）（P < 0.05），但与较重的同窝仔相比，GBP1（炎症调节因子）和 HSD11β1（应激激素）基因的 mRNA 表达倾向于更高（P < 0.10）。排除 HSD11β1 基因，所有这些最初在出生时观察到的轻重和中重仔猪肠道基因表达差异在哺乳期结束时稳定下来，此时其他基因出现。与中等体重的同窝仔猪相比，参与屏障功能 (CLDN1)、促炎反应 (CXCL2、IL6、IDO1) 和应激激素信号 (HSD11β1) 的基因过度表达 (P < 0.05)。总之，在出生时和哺乳期结束时，轻体重仔猪的基因表达似乎受损，因此营养吸收受损，