Comparative Nutritional and Histological Analysis of Malabar Red Snapper ( Lutjanus malabaricus ) and Asian Seabass ( Lates calcarifer ).

This study offers a comprehensive morpho-histological analysis of the gastrointestinal tract (GIT) of the Malabar red snapper. A comparison of its GIT morphology with that of the Asian seabass reveals similarities and differences between the two species. Additionally, the moisture content, crude protein, and ash in the fillets of Malabar red snapper and Asian seabass were slightly different, with Malabar red snapper exhibiting higher levels of essential fatty acids. Furthermore, higher levels of the polyunsaturated fatty acid (PUFA)/saturated fatty acid (SFA) ratio and docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) ratio, and a lower omega-6/omega-3 ratio, were observed in Malabar red snapper compared to Asian seabass. The Malabar red snapper's esophagus featured protective mechanisms such as simple columnar epithelial cells, mucous-secreting glands, and goblet cells that were predominantly stained for acid and neutral mucosubstances. Furthermore, its stomach, with mucus cells that were weakly stained for acid mucosubstances, exhibited distinct regions with varying glandular densities, with the pyloric region featuring few glands. The pyloric caeca of the fish were composed of five finger-like structures and few goblet cells. Several goblet cells gradually increased from the anterior to the posterior region of the intestine. These findings provide useful insights for the aquaculture sector, focusing on Malabar red snapper.