Pre- and postnatal development of rabbit small intestine; a light and scanning electron microscopic study

ABSTRACT

The small intestine is a highly differentiated organ that accomplishes both digestive and absorptive functions with great efficiency. The small intestine of rabbit was studied from early prenatal stage to full term in 15 fetuses and during the early days of life till maturity in 21 rabbits using light and scanning electron microscopy. In 15 days old fetuses, the epithelium was flat and stratified and the lumen was elliptical in shape. By the E18, the epithelial ridges were formed. The first rudimentary villus formation was formed in 21 days old fetuses and the true villi appeared by 24[th] days of gestation. At 27 days old fetuses, intestinal glands were not appeared yet. By the first day of postnatal life the duodenal glands appeared. The histological maturity of the rabbit small intestine occurred one month after birth. In conclusion, at all stages, the sequential morphologic changes of the rabbit small intestine developed to meet the structural and physiological demands during the fetal stage to be prepared to extra uterine life