Histomorphological studies of the gizzard in Post-hatch guinea fowls (Numida meleagris)

Abstract

The wall of the gizzard of guinea fowl consisted of five tunics namely, koilin (internal lining), mucosa, submucosa, muscularis and an outermost serosa except in the regions of tendon which lacked muscularis. The koilin was well developed in birds of all age groups with dentate projections on its luminal surface. The epithelial layer of mucosa was in the form of arches and gastric pits. Glands with loose connective tissue formed the lamina propria. Secretions from the glands drained through gastric pits and with the desquamated cells of the arches were found to form the koilin. Muscularis mucosa was completely absent. The submucosa was made of connective tissue with extensions into lamina propria and tunica muscularis. A single layer of thick extensively developed smooth circular muscle formed the tunica muscularis in the regions of body whereas; in the regions of blind sac it was moderately developed with an additional inner thin longitudinal smooth muscle layer. In between muscularis and outermost serosa were the nerve plexuses.