Impacts of bentonite supplementation on growth, carcass traits, nutrient digestibility, and histopathology of certain organs of rabbits fed diet naturally contaminated with aflatoxin.

The present study was conducted to investigate the effect of graded levels of dietary bentonite supplementation on growth performance, carcass traits, nutrient digestibility, and histopathology of certain organs in rabbits fed a diet naturally contaminated with aflatoxin. In total, 125 weanling New Zealand White male rabbits were randomly assigned to five treatment groups each of five replicates. Treatments were as follows: T1, basal diet with no aflatoxin and no additives (positive control diet, PCD); T2, basal diet naturally contaminated with 150 ppb aflatoxin and no additives (negative control diet, NCD); T3, NCD plus 0.5% Egyptian bentonite; T4, NCD plus 1% Egyptian bentonite; and T5, NCD plus 1% Egyptian bentonite. The experiment lasted for 8 weeks. Results showed a significant decrease (P < 0.05) in the body weight and the body weight gain in the NCD, while they were improved (P < 0.05) in groups fed diets supplemented with different levels of bentonite. The relative weight of the liver and kidneys were higher in the NCD, while the liver weight was relatively high in the group fed NCD supplemented with 0.5% bentonite, and it was not significant in other bentonite-supplemented groups. Bentonite supplementation improved the digestibility coefficients of various nutrients. Bentonite addition decreased the histopathological lesions in liver, kidney, and intestine caused by aflatoxin-infected diets. In conclusion, bentonite supplementation overcame the negative effect of aflatoxin, enhanced growth performance traits, decreased the relative weights of the liver and the kidney which are usually increased by aflatoxin, caused significant improvement in nutrients' digestibility, and decreased the histopathological lesions caused by aflatoxin-infected diets. The level of 2% bentonite is recommended for ameliorating the aflatoxin effects.