Ultrastructural and histological study of intestine of adult Nile Tilapia (Oreochromis Niloticus)

Abstract

The tilapia intestine is essential for both digestion and nutrient absorption, making its structural analysis crucial for understanding its functional adaptations. This study sought to examine the histological, ultrastructural, and histochemical features of the intestine in adult Nile Tilapia (Oreochromis niloticus) by employing histology and scanning electron microscopy (SEM). The histological analysis revealed that the mid-intestinal mucosa was composed of short, longitudinal folds. Intestinal villi lined with simple columnar epithelium with numerous goblet cells relatively in a deeper position. Wandering cells appeared rounded cells with round nuclei basally located and migrated to the surface. The goblet cells displayed a positive reactivity to both Alcian blue (AB) and Periodic acid schiff (PAS).scanning electron microscopy (SEM) revealed that the mid-intestinal mucosa revealed the existence of irregular wavy folds. Intestinal mucosa showed honey bee-sided enterocytes with sac-like goblets. The striated borders between adjacent cells are clearly visible. These cells microvillus boundaries were clearly distinguishable as light bands which covered the cell apex. Enterocyte columnar cells were interspersed with goblet cells containing mucus. Prominent large pores on the villus surface lead to goblet cells. In conclusion, these findings enhance our comprehension of the structural adaptations of the intestine for digestion and nutrient absorption in this species.