Histogenesis of intestinal villi in fowl (Gallus domesticus)

Abstract

The study on development, age changes lind regional differences of intestinal villi was conducted in 18 prehatch and 42 posthatch chicles of White Leghorn (WLH) birds divided into 10 groups with 6 birds in each group. The entire intestinal mucosa of fowl showed villi of variable shape and size. However, these were longer and numerous in small intestine than in large intestine. Among the parts of intestine the villi were longest (1260.00 µm) in duodenum, The villi were short and cylindrical in early groups and appeared thin, long and cylindrical in the chicks of zero day, changing to foliate and slender shape in the chicks of 1 week onward, In jejunum the villi were cylindrical and maximum (48/field) in number in the embryos of 19 days of incubation while in later groups these appeared short, club-shaped and less numerous. In ileum villi were either club shaped or cylindrical in embryos of 19 days and long cylindrical without secondary villi in later groups. In caecum and colon characteristic folds with secondary villi were present. The lining epithelium covering the villi was low, columnar in the embryos of 12 days of incubation and increased in height from day 12 of incubation to 1 week of age. The goblet cells increased caudad and were maximum in colon.