Effects of Zeolite Nano-Structure on Experimental Chronic Toxicity of Aflatoxin B1 in the Diet of Rainbow Trout (Oncorhynchus mkiss) and Evaluation of Growth and Physiological Indices

The present study was carried out to evaluate the effects of dietary nano-structured zeolite (NZ) levels on reduction of aflatoxin B1 (AFB1) in the diet of rainbow trout (Oncorhynchus mykiss) for 56 days. For this purpose, 270 fish (23 ± 3.7 g) were randomly distributed into 6 groups including C (control), NZ0.5 (basic ration 0.5 % nano-structure zeolite), NZ1 (basic ration 1 % nano-structure zeolite), AF5 (basic ration 5 mg aflatoxin B1), AF5NZ0.5 (basic ration 5 mg aflatoxin B1 0.5 % nano-structure zeolite), AF5NZ1 (basic ration 5 mg aflatoxin B1 1 % nano-structure zeolite) each with three replicates. Juveniles were fed satiated 4 times a day. At the end of the experiment, there was no significant difference among the treatments in growth indices. The hepatosomatic index, number of white blood cells and neutrophil decreased significantly in treatment AF5NZ0.5 and lymphocyte level increased in comparison to NZ0.5 treatment. On the other hand, eosinophil level increased significantly in treatment NZ0.5 compared with AF5 treatment. Other hematological parameters showed no significant differences among the treatments. Total protein and albumin concentrations in the treatments containing aflatoxin had a significant decrease compared with the other treatments. Also globulin level in treatment AF5 decreased significantly compared to the control group. Phosphorus content in serum was significantly higher in group NZ0.5 compared with C group, but other biochemical parameters such as sodium, calcium and cholesterol were not significantly different among the specimens that were fed different diets. According to the present study, it can be suggested that 0.5 % of zeolite nano-structure in the diet can reduce the harmful impacts of aflatoxin B1 and improve health status of trout.