Histomorphometric study of the goat stomach during prenatal development

Histological and histomorphometric study of the cranial digestive tract of ostriches (Struthio camelus) with advancing age

The present study was conducted to determine the histological and histomorphometric variations in the tongue, oesophagus, proventriculus, and gizzard of ostriches (Struthio camelus) with regards to the sex and advancing age. A total of 40 healthy ostriches of both sexes and five age groups; young (up to 1 year, 1 to 2 years and 2 to 3 years) and adult (3 to 4 years and above 4 years) in equal numbers (n = 8) were used in this study. The organs under study were collected immediately after slaughtering the birds. Overall, the colour, shape, weight and various dimensions (length, width, and diameter) of the collected organs were recorded. The mean values of the gross anatomical variables of the studied organs increased (P < 0.05) among all the young groups (i.e., from 1 to 2 years, 2 to 3 years). Similarly, the organs under study in the adult groups (birds aged 3 to 4 years and above 4 years) grew (P < 0.05) as well. However, the differences between the adults were not significant. The histological analysis and histometric measurements were conducted on paraffin embedded tissue sections with Image J® analysis software. The statistical analysis revealed a significant increase in the thickness of the different tunics of the digestive organs in all the groups except those the adult groups. These findings may be of importance for the strategic manipulation of feed and nutrition to enhance the growth rate and also to diagnose pathological processes.

Prenatal development of the stomach in the goat (Capra hircus)

<b> During organogenesis in the developing goat embryo, a four-chamber stomach is formed from an extension of the primary intestine. Due to histological and morphological changes, each chamber of the stomach takes on characteristic features associated with its function. The histological structure of the stomach wall consists of four layers, the mucosa, submucosa, tunica muscularis and serosa. This work presents the current state of knowledge of the changes observed in each layer of the developing stomach and its morphogenesis in the prenatal period. Practical applications of this information in prenatal ultrasound diagnostics in goats are suggested as well. </b>

Prenatal histomorphological development of the reticulum in fallow deer (Dama dama)

The histomorphological changes occurring in the Dama dama reticulum during prenatal development have been investigated. Twenty-five Dama dama embryos were used, from the first stages of prenatal life until birth. Differentiation of the reticulum was observed at 23% gestation. By 25% gestation the reticular wall comprised three layers: an internal epithelial layer, a middle layer of pluripotential blastemic tissue and an external layer or serosa. Primary reticular crests were visible at 38% gestation. Secondary reticular crests were observed at 61% gestation. Neuroendocrine cells were detected by synaptophysin (SYP) at 35% gestation, in the lamina propria-submucosa, tunica muscularis, and serosa. Epithelial Cytokeratin-18 (CK-18) cells were observed at 35% gestation extended throughout the epithelial layers. The glial cells (vimentin -VIM- and glial fibrillary acidic protein-GFAP-markers) were discerned at 25% and 43% gestation, respectively, in myenteric and submucosal plexuses, lamina propria, muscularis mucosae, tunica muscularis, and perivascular connective tissue. The neuropeptide Y (NPY) and vasoactive intestinal polypeptide (VIP) markers were immunodetected at 75% and 80 gestation, respectively, in the lamina propria-submucosa, muscularis mucosae, tunica muscularis, serosa, and myenteric plexuses. The prenatal development of the fallow deer reticular mucosa evidenced a considerable precocity similar to that previously reported in goat and red deer.

The embryonic development of the bovine stomach revisited

The adult anatomy and physiology of the bovine (Bos taurus) stomach have been investigated extensively. Despite the many studies, however, the early development of the stomach has not yet been fully elucidated. The goal of the present study, therefore, was to review the available literature, to visualize the embryonic and early foetal development of the bovine stomach and to shed light on unresolved issues. The stomachs of fifteen bovine embryos and eleven foetuses from 26 to 80 days of gestation were photographed both in situ and after exenteration and critical point drying. A series of photographs was obtained that yielded a contiguous and comprehensive view of all the developmental changes that occurred until the virtually final configuration of the stomach was attained. In addition, the serosal surface was studied by electron microscopy, thus revealing subtle regional differences in the lining of the peritoneal cavity. Our observations corroborate the contention that all the compartments evolve from the fusiform primordium and that no outgrowth at the level of the oesophagus occurs. The greater curvature as well as the attachment line of the dorsal mesogastrium shift to the left, which is similar to the process in monogastrians. The rumen and reticulum develop from separate protrusions, and further compartmentalization results from constrictions and bulges and not from folding. Between 55 and 60 days of gestation, the entire bovine stomach except for the abomasum eventually relocates to its final position. In summary, previously debated key issues were addressed and integrated with current findings.