The effect of prebiotic pretreatment on histological lesions of Nile tilapia fry (Oreochromis niloticus) exposed to silver nanoparticles

The presence of emerging nanoparticle contaminants in aquatic environments reduces the safety performance of aquatic animals, so the use of safety stimuli is essential. The aim of the present study was to investigate the effect of different prebiotic levels of oyster mushrooms (Pleurotus ostreatus) on tissue damage in the liver and gills of tilapia exposed to silver nanoparticles. For this purpose, 120 juveniles of Tilapia (Oreochromis niloticus) were divided into 4 experimental groups with 3 replicates and bred for 42 days including treatment 1 as control (fed with diet without probiotic) and treatments 2-4, fed with diet containing 0.05%, 0.1% and 0.2% prebiotics, then 5 ppm of silver nanoparticles were added to the culture medium of each treatment for 16 days. At the end of the experimental period, fish were anesthetized with clove anesthetic solution (220 mg/L) and their liver and gill tissues were isolated for histological studies. Treatments exposed to silver nanoparticles showed extensive complications in gill tissue as well as severe injuries and bile stasis in liver tissue. However, the use of mushroom prebiotics was able to reduce the destructive effects of silver nanoparticles on these tissues. Overall, the results indicated that treatment with 0.2% of prebiotics in the diet could have the best protective effect on tissue damage in the liver and gills of tilapia exposed to silver nanoparticles