Thesis on the Histological studies on the mucosae of the small & large intestines of the Egyptian water buffalo (Bos bubalus L.) during the prenatal stage

The histogenesis of the intestinal mucosae of the Egyptianwater buffalo-fetus passes through a previllous and avillous stage with an extra post~villous stage in the largeintestine.In the previllous stage, the intestinal mucosae consist ofa Lamina epithelialis, made up of poorly differentiateddensely packed cells and a Lamina propria/submucosa, madeup of homogeneous avascular mesenchyme. Both, the epithelialluminal surface and the epithelio-mesenchymalinterfaceare even.villous stage begins in the fetus of 7.5 cm CRL, whenthe mucosa gives knob-like projections in the duodenum andtrans~to~y longitudinal folds in the jejunum, ileum, cecum,colon and rectum. Any of these structures consists of aluminal epithelial outgrowth and a vascularized mesenchymalstalk. Tae villi increase in number by splitting of thekriob-like projections and the folds by invaginations. Thegrowth 01 the villi advances in a cranio-cac.dal directionin thB small intestine and in a caudo-cranial one in thelarge intestine. The differentiation of the epithelium into