Departamento de Química, Universidad Nacional de Río Cuarto, Río Cuarto, Córdoba, Argentina.
Poult Sci. 2011 Feb;90(2):352-7. doi: 10.3382/ps.2010-00834.
Clay feed additives have been increasingly incorporated into animal diets to prevent aflatoxicosis. Due to the nonselective nature of the binding interaction, many important components of the diets could also be made unavailable because of these feed additives. The anticoccidial monensin (MON) could also be sequestered by these clays. The use of sodium bentonite (Na-B) from a mine in the province of Mendoza, Argentina, was investigated as a sequestering agent to prevent the effects of 100 µg/kg of dietary aflatoxin B(1) (AFB(1)). In vitro studies demonstrated that the above Na-B was a good candidate to prevent aflatoxicosis. They also showed that MON competes with AFB(1) for the adsorption sites on the clay surface and effectively displaces the toxin when it is in low concentration. Even though the levels of MON in diets, approximately 55 mg/kg, are high enough to not be significantly changed as a consequence of the adsorption, they can further affect the ability of the clays to bind low levels of AFB(1). An in vivo experiment carried out with poultry showed that 100 µg/kg of AFB(1) does not significantly change productive or biochemical parameters. However, liver histopathology not only confirmed the ability of this particular Na-B to prevent aflatoxicosis but also the decrease of this capacity in the presence of 55 mg/kg of MON. This is the first report stressing this fact and further research should be performed to check if this behavior is a characteristic of the assayed Na-B or of this type of clay. On the other hand, the presence of MON should also be taken into account when assaying the potential AFB(1) binding ability of a given bentonite.
粘土饲料添加剂已越来越多地被纳入动物饲料中，以预防黄曲霉毒素中毒。由于结合相互作用的非选择性，许多重要的饲料成分也可能因为这些饲料添加剂而变得无法获得。抗球虫药莫能菌素（MON）也可能被这些粘土螯合。来自阿根廷门多萨省的一个矿的钠膨润土（Na-B）被用作螯合剂，以防止 100µg/kg 的饮食黄曲霉毒素 B(1)（AFB(1)）的影响。体外研究表明，上述 Na-B 是一种很好的候选物，可以预防黄曲霉毒素中毒。它们还表明，MON 与 AFB(1)竞争粘土表面的吸附位点，并在浓度低时有效地取代毒素。尽管饲料中的 MON 水平（约 55mg/kg）足够高，不会因吸附而发生显著变化，但它们可以进一步影响粘土结合低水平 AFB(1)的能力。在禽类进行的体内实验表明，100µg/kg 的 AFB(1)不会显著改变生产性能或生化参数。然而，肝组织病理学不仅证实了这种特殊的 Na-B 预防黄曲霉毒素中毒的能力，而且还证实了在存在 55mg/kg MON 的情况下这种能力的降低。这是首次强调这一事实的报告，应该进一步研究以检查这种行为是否是所测试的 Na-B 或这种类型的粘土的特征。另一方面，在测试特定膨润土对 AFB(1)的潜在结合能力时，也应考虑 MON 的存在。
