Efficacy of activated diatomaceous clay in reducing the toxicity of zearalenone in rats and piglets

Two experiments were conducted to evaluate the efficacy of an activated diatomaceous clay (ADC) in reducing the toxic effects of zearalenone (ZEA) in the diet of rats and piglets. In the rat experiment, 90 Sprague-Dawley female weanling rats with an initial BW of 45 +/- 1.0 g were assigned to 1 of 6 dietary treatments for 28 d in a completely randomized design (CRD) with a 2 x 3 factorial arrangement (0 or 6 mg ZEA/kg feed and 0, 1, and 5 g ADC/kg feed). In the piglet experiment, 64 female piglets ([Large White x Landrace] x Pietrain with an initial BW of 14.9 +/- 1.65 kg) were fed 1 of 8 experimental diets for 26 d in a CRD design with a 2 x 4 factorial arrangement (0 or 0.8 mg ZEA/kg feed and 0, 1, 2, and 5 g ADC/kg feed). The ADFI, ADG, and G:F were determined at the end of each experiment. At the conclusion of studies, serum samples were collected and rats and piglets were euthanized to determine visceral organ weights. The diet contaminated with ZEA did not alter the growth of rats and the relative weight of liver and kidneys. However, ZEA increased (P < 0.05) the relative weight of uterus, ovaries, and spleen and decreased (P < 0.05) the serum activities of alkaline phosphatase and alanine aminotransferase compared to the control group. Supplementation of ADC in the rat diets counteracted (P < 0.05) the observed toxic effects of ZEA on the uterus and ovaries weight. The diet contaminated with ZEA (0.8 mg/kg feed) increased (P < 0.05) the weight of the uterus and ovaries in piglets but did not modify the serum biochemical variables or the relative weight of other visceral organs. The addition of 5 g ADC/kg to the contaminated feed reduced the toxic effects of ZEA on uterus and ovary weights to that of the control group. Zearalenone (10.5 mu g/kg bile) and a-zearalenol (5.6 mu g/kg bile) residues were detected in the bile of piglets fed the ZEA treatment. Supplementation of ADC to diets contaminated with ZEA reduced (P = 0.001) ZEA content in bile compared to the ZEA treatments. The results of these experiments indicate that a long-term consumption of ZEA-contaminated diets stimulated growth of the reproductive tract in rats and piglets and the presence of ZEA residue in bile in piglets. These effects may be counteracted by the addition of ADC to the diet.