Smirnov A, Tako E, Ferket P R, Uni Z
The Faculty of Agricultural, Food and Environmental Quality Sciences, Department of Animal Sciences, Hebrew University of Jerusalem, PO Box 12, Rehovot, 76100, Israel.
Poult Sci. 2006 Apr;85(4):669-73. doi: 10.1093/ps/85.4.669.
The protective mucus layer covers the entire surface of the gastrointestinal tract. The mucus layer also acts as a medium for molecule transport between the luminal contents and the enterocytes; therefore it has a major role in nutrient absorption. The main mucus layer component, mucin glycoproteins, is produced by mucous-secreting goblet cells. In chicken small intestine, functional development of goblet cells and enterocytes occurs in the late embryonic and immediate posthatch period. Presence of the nutrient is crucial for mucosal development. Feed deprivation immediately after hatch caused delayed mucosa development and perturbed mucin dynamics. Recent studies showed the intraamnionic nutrient supply (in-ovo feeding; IOF) accelerated mucosa functional development. In this study, the effect of IOF on the mucin mRNA expression and mucin content in the goblet cells was studied. The feeding solution containing carbohydrates was administered to the amnionic fluid of the Cobb embryos at d 17.5 of incubation. Samples from the jejunum were taken at d 17 of incubation (before IOF), and then 10 embryos from each group were sampled at 19 d of incubation, at hatch, and at d 3 posthatch. Following IOF, villus surface area increased at day of hatch and 3 d posthatch by 27 and 21%, respectively. In addition, the proportion of goblet cells containing acidic mucin increased 36 h after injection by 50% compared with the controls. The mucin mRNA expression increased gradually from d 17 of incubation to 3 d posthatch. Enhanced expression of the mucin mRNA was found at the day of hatch in chicks that received carbohydrate solution into the amnionic fluid in comparison with the control group. The results showed that providing the carbohydrates as an energy source to the late-term embryo had a trophic effect on the small intestine and enhanced goblet cell development.
保护性黏液层覆盖胃肠道的整个表面。黏液层还充当管腔内容物与肠上皮细胞之间分子运输的介质；因此，它在营养吸收中起主要作用。黏液层的主要成分黏蛋白糖蛋白由分泌黏液的杯状细胞产生。在鸡的小肠中，杯状细胞和肠上皮细胞的功能发育发生在胚胎后期和孵化后即刻。营养物质的存在对黏膜发育至关重要。孵化后立即禁食会导致黏膜发育延迟和黏蛋白动态变化紊乱。最近的研究表明，羊膜内营养供应（胚内喂养；IOF）加速了黏膜功能发育。在本研究中，研究了IOF对杯状细胞中黏蛋白mRNA表达和黏蛋白含量的影响。在孵化第17.5天，将含有碳水化合物的喂养溶液注入科布胚胎的羊水中。在孵化第17天（IOF前）采集空肠样本，然后在孵化第19天、出雏时和出雏后第3天从每组中选取10个胚胎进行采样。IOF后，出雏时和出雏后3天绒毛表面积分别增加了27%和21%。此外，与对照组相比，注射后36小时含酸性黏蛋白的杯状细胞比例增加了50%。黏蛋白mRNA表达从孵化第17天到出雏后第3天逐渐增加。与对照组相比，在羊水中接受碳水化合物溶液的雏鸡出雏时黏蛋白mRNA表达增强。结果表明，向晚期胚胎提供碳水化合物作为能量来源对小肠具有营养作用，并促进了杯状细胞的发育。
