The present histological study was conducted on ileum of different postnatal age groups of guinea pig. Histologically the wall of the ileum composed of the four layers viz., tunica mucosa, tunica sub mucosa, tunica muscularis and tunica serosa. The shape of the villi in the epithelium was slender and finger like in the 0-2 week-old guinea pig where as tongue shaped in remaining age groups. Lamina propria composed of the loose connective tissue with Crypts of the Lieberkuhn. Tunica submucosa was made up of more number of collagen and reticular fibres and few elastic fibres in the wall of the blood vessels. Tunica muscularis was lined by the inner circular and outer longitudinal muscular layer. The mean height and width of the villi and height of the columnar cells and thickness of the tunica muscularis was increased as the age advanced in all the age groups studied.

Highlights

• Age related changes in the ileum of guinea pig.
• Micrometrical studies on the ileum in different age groups