ORGANOGENESIS AND EARLY HISTOGENESIS OF THE CAPRINE STOMACH

Abstract

This study was carried out to illustrate the organogenetic and early histogenetic changeof the goat stomach during the intrautrine life (from 21-150 day-old) l,lsing st reoscop and light microscope.

The results of the organogenetic study can be summerized as follows: * All compartments of goat stomach were originated from an

independent gastric primordium without any esophageal contribution.

* The gastric primordium was detected firstly at 21 day-old (1-25•cm VRL) as spindle shape with dorsal and ventral convex curvatures. The lumen of the gastric primordium was divided by two illdistinct longitudinal endodermal folds. The latter became distinct as mesodermal ridges with further increased age (23 day-old). * The gastric primordium gradually rotated, with an acute angle, toward the left side at 23 day-old then with right angle at 34 day-old. * The ruminoreticulum was seen firstly (at 24 day-old) as craniodorsal projection from the fundus. Then separated by rumina-reticular groove at 27 day-old during the latter age, the four gastric compartment would be recongized.

* The rumina! vestibule was firstly appeared (at 27 day-old) in area between rumen and reticulum. * The cranial transverse groove was recognized firstly as small caudal transverse groove between vestibule and rumen (at 27 day-old) while the caudal groove appeared (at 34 day-old) between the two rumina!

prommence.

* The rumina!sacs were firstly observed (at 34 day-old) as two rumina!

prominences separated by shallow groove and directed cranioventrall