Mucin gene expression and mucin content in the chicken intestinal goblet cells are affected by in ovo feeding of carbohydrates

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.