Gross and histological studies of digestive tract of broilers during postnatal growth and development

Abstract

We studied anatomy and histology of different segments of the digestive tract in postnatal growing broiler chickens with regard to their location, shape, size and weight. A group of four chickens, each at day 1 (D 1) , days 14 (D 14) and days 28 (D 28) , total 12, were killed, their digestive tracts were dissected and described and shape, size and weight of different segments were recorded. Samples from different segments were prepared and stained with haematoxylin and eosin staining technique to study the histology under light microscope. The average lengths (cm) and weights (gm) of esophagus, proventriculus (glandular stomach), gizzard (muscular stomach), small intestine and large intestine were significantly higher (P<0.01) in chickens at D 28 than that at D 14 and at D 1. The histological layers of digestive tract were lamina epithelia, lamina propria, lamina muscularis, submucosa, tunica muscularis and serosa with the exception in esophagus where outer adventitia was found. The esophageal glands were significantly more in numbers at D 1 (in cross section, 12 in number per focus under 100x) than at D 14 (6 in number per focus under 100x) and at D 28 (2 in number per focus under 100x). The proventriculus consisted of macroscopic papillae with numerous microscopic folds with lamina propria comprised of simple glands, which converged into a common cavity near the surface. In gizzard, the cuticle, in the form of wavy lines ran parallel to the surface. The villi of small intestine and large intestine were lined by simple columnar epithelium. The apical parts of villi of the duodenum were slightly pointed and the basal parts of the villi were thicker than jejunum and ileum, whereas, the villi of the jejunum and ileum became shorter and broader than duodenum and most of the villi had blunt apical part and the basal parts were wider. The numbers of goblet cells were numerous in number in ileum than duodenum and jejunum. Plicae ran along the inner surface of the distal two thirds of the cacea. However, in the colorectum, the villi appeared as numerous long flat leaf-shaped structures which filled a large proportion of the lumen. The average lengths and widths of villi of small and large intestine were significantly higher (P<0.01) in chickens at D 28 than that at D 14 and at D 1. The number of goblet cells in lamina epithelium and intestinal glands of the lamina propria were numerous in number at D 28 than the chickens at D 14 and at D 1.

Histological, Histomorphometrical and Histochemical Studies on the Large Intestine of Uttara Fowl

“…The lymphoid tissues were found to be present in mucosa, submucosa and core of villi. These findings are in line with the findings of Majeed et al, (2009), Samte (2008 and Nasrin et al, (2012). The lamina muscularis mucosae in both caeca and colorectum consisted of thin layer of muscles which extended to the core of villus in the mucosal folds.…”

“…The lamina propria, submucosa and core of villi consisted of loose connective tissue fibres infiltrated with large number of lymphocytes. Similar observations were recorded by Majeed et al, (2009), Nasrin et al, (2012 in chicken and Samte (2008) in Kadaknath fowl. An aggregation of lymphocytes forming a nodular appearance was seen towards the base of crypts of Lieberkuhn in the lamina propria in 28 and 112 days old birds but they were not noted in other studied age groups.…”

“…Similar observations have also been reported by Nickel et al, (1977), Ushakumary et al, (1994), Sisson and Grossman (1953), Samte (2008) and Nasrin et al, (2012). The tunica mucosa layer possessed considerable complexity, being thrown into well-developed folds.…”

“…tunica mucosa, tunica submucosa, tunica muscularis and tunica serosa and caecum was divided into proximal, middle and distal portions in all studied age groups as observed by Nasrin et al, (2012), Majeed et al, (2009), Samte (2008, Dellmann and Eurell (1998). The surface epithelial lining consisted of simple columnar cells and goblet cells.…”

Impact of Autonomic Tonus Typological Features on the Duodenum Structure of Chickens

“…Adaptation processes that adjust its morphological peculiarities and functional characteristics constantly take place there. [1][2][3][4][5][6] These processes are influenced by a variety of internal and external environment factors that are mutually intertwined and exert a complex impact on the organism. Genetic factor occupies a dominant position in determining the morphological and functional intestinal wall profile.…”