Development of the Bovine Ileal Mucosa

Abstract

The development of the bovine ileal mucosa was studied with particular reference to maturation during the fetal and neonatal period. In this region, by 4–5 months of fetal development, vacuolation of the epithelial cells had occurred on the villi, and the goblet and absorptive cells in the crypts were present. By 6–9 months, the villi were longer and more numerous than in the previous stages. At the same time, the vacuolated cells could be seen predominantly on the upper half of each villus. The absorptive cells and goblet cells were more distinct in the crypt and lower half of each villus. Moreover, the goblet cells showed differences in mucin, while in the submucosa the lymphoid follicles were seen to have enlarged to become a prominent feature of the Peyer’s patches at this stage. At birth, in suckled animals, the ileal cells on the lower area of each villus and in the crypt appeared more like mature cells. In contrast, there were numerous inclusion bodies in epithelial cells on the upper half of each villus. They appeared in the apical portion of the cytoplasm as vacuoles with stainable or dense contents. By 1 week, however, epithelial cells no longer contained inclusion bodies, and absorptive and goblet cell populations had begun to emerge from the crypts.These histological results suggest that the bovine ileal mucosa has two distinct turning points during its development in the fetus and the neonate. Initially all the mucosal structures are present in fetuses at 6–7 months of gestation, and then the vacuolated cells covering the ileal villi are replaced by mature, nonpinocytosing epithelium which emerges from the crypts on or before the 7th day after birth (ileal closure).

Expression and Distribution of Myoepithelial Cells in Developing Bovine Parotid Gland

“…On the histogenesis of bovine digestive tissues, several studies have been conducted by Asari et al (1984Asari et al ( , 1985Asari et al ( , 1987Asari et al ( , 1994. In bovine fetal abomasum, the most distinct histological changes during development were found to occur with the first appearance of gastric parietal and chief cells at almost the same stage, while in fetal Heal mucosa, goblet cells, absorptive cells in the intestinal crypts and vacuolated cells in the villi were present along all segments by 6-7 months.…”

The Prenatal Development and Histochemistry of the Ileal Mucins in the Bovine Fetuses

“…Development of intestinal villi continues all through the conception. Rudimentary villi are present at the first 3 months of gestation, whereas typical intestinal villi are found between the fourth and fifth months of gestation in the fetal bovine ileum (Asari et al., 1987). The first ileal Peyer patches appear between the fifth and sixth months of gestation and continue to mature till the birth (Beyaz and Asti, 2004).…”

Intestinal fatty acid–binding protein: a possible marker for gut maturation

“…During early fetal life, the intestinal epithelial lining consists of vacuolated, immature enterocytes, as shown in animal models and in the human gut (13)(14)(15). These immature cells gradually disappear with increasing gestational age (GA) and are completely replaced by mature enterocytes shortly after birth (14,16). More insight on I-FABP distribution and its release into the circulation as an indicator of gut maturity can aid in the management of gut-associated problems in premature neonates.…”

“…Moreover, I-FABP reflects enterocyte turnover and is exclusively present in mature enterocytes of the small and large intestine (11,12). During early fetal life, the intestinal epithelial lining consists of vacuolated, immature enterocytes, as shown in animal models and in the human gut (13)(14)(15). These immature cells gradually disappear with increasing gestational age (GA) and are completely replaced by mature enterocytes shortly after birth (14,16).…”