Efficacy of Mozambican bentonite and diatomaceous earth in reducing the toxic effects of aflatoxins in chicks

Abstract

The effectiveness of diatomaceous earth (DE) and bentonite clay (BC) in reducing the toxic effects of aflatoxin B1 (AFB1) in chicks was assessed. A total of 150 day-old male broiler chicks were assigned to six dietary treatments, with 5 replicate pens of five chicks per treatment. Dietary treatments were: (1) a positive control basal diet (BD) containing no AFB1, no BC and no DE; (2) BD + 0.50% BC but with no AFB1 and DE; (3) BD + 0.50% DE but with no AF and BC; (4) BD + 2 mg AFB1/kg diet but with no BC and DE; (5) BD + 0.50% BC + 2 mg AFB1/kg diet but with no DE; and (6) BD + 0.50% DE + 2 mg AFB1/kg diet but with no BC. Compared with controls, feed intake (FI) and body weight gain (BWG) were depressed (P<0.05) in chicks fed AFB1, with greater reduction in FI and BWG observed in birds fed the AFB1 plus 0.50% DE diet. Feed conversion ratio was similar. Chicks fed AFB1 alone had increased (P<0.05) relative liver weights compared to all other dietary treatments except for chicks fed AFB1+ DE. Chicks fed AFB1 alone and those fed AFB1+ DE had heavier (P<0.05) relative kidney weights compared to chicks fed other treatments. Compared with the control chicks, livers from birds fed dietary AFB1 and AFB1 plus DE were similar. Liver lesion score of chicks fed AFB1 plus BC was lower (P<0.05) than that of chicks fed AFB1 but higher (P<0.05) than that of control chicks. Compared to controls, serum concentrations of glucose, albumin, total protein globulin, and calcium were decreased (P<0.05) in chicks fed AFB1 alone, whereas serum concentrations of aspartate amino transferase and gamma glutamyl transferase were increased (P<0.05). It can be concluded that this concentration of BC was partially effective in reducing the toxic effects of 2 mg/kg AFB1, whereas DE at the same concentration was not effective in reducing the toxic effects of 2 mg/kg AFB1.