Nano-zeolite efficiency to mitigate the aflatoxin B1 (AFB1) toxicity: Effects on growth, digestive enzymes, antioxidant, DNA damage and bioaccumulation of AFB1 residues in Nile tilapia (Oreochromis niloticus)

The feeding trial was conducted to investigate the beneficial impacts of natural clay nano-zeolite against feed contaminated with 3 ppm aflatoxin B1 (AFB1) on Nile tilapia, Oreochromis niloticus. Five hundred and forty fish fingerlings (7.75 +/- 0.06 g), were distributed to six groups (30 fish group(-1)) with three replicates. A basal diet containing (306 g kg(-1) protein) and isocaloric (19.53 MJ kg(-1) gross energy) were formulated. The basal diet was exposed to different dose of AFB1 (0 and 3 ppm) each level was supplemented with three dietary levels of nano-zeolite (0, 5 and 10 g kg(-1)). After 84 days, growth performance and feed utilization were significantly higher in fish fed diet with 3 ppm AFB1 and supplemented with 5 or 10 g kg(-1) nano-zeolite than diet with 3 ppm AFB1 without nano-zeolite. In addition, higher secretion of endogenous amylase and chymotrypsin were detected in fish fed diet with 3 ppm AFB1 and supplemented with nano-zeolite inclusion at level 5 g kg(-1) than other treatment diets. Hemoglobin, hematocrit, red blood cells, white blood cells count were significantly higher in the group fish fed diet containing 10 g kg(-1) nano-zeolite and exposed to AFB1 than other exposed to AFB1 without nano-zeolite inclusion. Diet supplemented with 10 g kg(-1) nano-zeolite and contaminated with AFB1 recorded the lowest serum alanine and aspartate aminotransferase, alkaline phosphatase, total protein, albumin and globulin than those exposed to AFB1 without nano-zeolite. Likewise, the antioxidant activities of MAD, SOD, CAT, lysozyme and DNA fragmentation have the same trend. However, adding 5 or 10 g kg(-1) zeolite in combination with AFB1 decreased the residual of AFB1 in fish muscle. In conclusion, AFB1 induced reduction in growth, feed utilization, digestive enzymes activities, and antioxidant enzyme activities; elevated the activities of liver enzyme, DNA damage, residual aflatoxin in Nile tilapia musculature; and nano-zeolite alleviated the AFB1 toxicity in O. niloticus, in addition nano-zeolite has beneficial effects to eliminate the negative impacts of AFB1 in health status of tilapia, thus further studies are necessary to clarify the remediation of nano-zeolite against the aflatoxin in aquafeeds along with paying attention to food safety concerns.