Efficacy of dietary chitosan and chitosan nanoparticles supplementation on health status of Nile tilapia, Oreochromis niloticus (L.)

Chitosan is drawing a lot of attention and starts to play a significant role in the sustainability of aquaculture. It meets the environmental criteria, which is an eco-friendly compound, helps the efficient use of reagents and reduction of possible waste as well. The current study was conducted to evaluate the effect of dietary supplements of chitosan (CS) and chitosan nanoparticles (CNP) at a level of 0.5 % on two different based diets on Nile tilapia health and innate immune responses. The experimental design was completely randomized with three replicates in a 2 × 3 factorial design; with two different based diets; FM (fishmeal-based diet) and GM (Gluten meal-based diet); with three forms of chitosan (zero-chitosan as a control, CS and CNP). chitosan form and dietary protein source significantly influenced the hematological indices, phagocytic activity and index, while RBCs, Hct, MCV, WBCs and Phagocytic activity were also significantly affected by both factors interaction (P < 0.05). Moreover, the antioxidant defense system activities and biochemical parameters were significantly affected (P < 0.05) by dietary protein source, chitosan form, and their interaction. Fish fed on GM diet recorded a remarkable reduction (P < 0.05) in immunity parameters, antioxidant system activities and the biochemical indices among all treatments. Conversely, fish fed on plant-base diet (GM) and received chitosan fortification especially CNP, recorded a significant enhancement (P < 0.05) in health status. Therefore, the present study recommends the addition of supplementary CNP to the Nile tilapia diet for better health and disease resistance, as well as augmentation of plant-based protein nutritional value.