Effet chez le porcelet d'une exposition à un régime co-contaminé en ...

INTRODUCTIONI. ADSORPTION OF MYCOTOXINSThe ever-increasing number of reports on the presence of mycotoxins in foods and feed dictatesthe necessity for practical and economical deactivation procedures.The high costs and limitations of physical and chemical treatments prompted a search for othersolutions to the mycotoxin hazard. Up to now, the most widely investigated method in this field isthe addition of nutritionally inert sorbents with the capacity to tightly bind and immobilizemycotoxins in the gastrointestinal tract of animals, resulting in a major reduction in toxin bioavailability.1) Use of inorganic adsorbentsIn several scientific studies clay and zeolitic minerals, hydrated sodium calcium aluminosilicates(HSCAS) and other similar montmorillonite and bentonite clays have proven to be the most promisingadsorbents for aflatoxins (AF) (Grant and Phillips, 1998; Ramos and Hernandez, 1996; Phillips et al.,1988, 1994; Vekiru et al., 2007). Mixed into feed they markedly diminished AF uptake by the bloodand distribution to target organs, thus avoiding aflatoxin-related diseases and the carryover ofaflatoxins into animal products such as milk (Phillips et al., 1990 and 1991). These binders have theproperty of adsorbing organic substances either on their external surfaces or within theirinterlaminar spaces, by the interaction with or substitution of the exchange cations present in thesespaces. However, clay and zeolitic minerals, which comprise a broad family of diversealuminosilicates, are not produced equally thus do not possess the same physical properties.While good and scientifically explained results were obtained in counteracting aflatoxins,adsorption of other mycotoxins (e.g. zearalenone, ochratoxin A, fumonisins) was limited or evenfailed under field conditions (e.g. trichothecenes such as deoxynivalenol, T-2 toxin) (Friend et al.,1984; Kubena et al., 1990; Huff et al., 1992; Kubena et al., 1993; Ramos et al., 1996).a) Hydrated sodium calcium aluminosilicate (HSCAS)HSCAS is a phyllosilicate clay. Its discovery as an effective enterosorbent of aflatoxins, its chemicalcomposition and its mechanism of aflatoxin sorption at interlayer surfaces is described in numerousscientific publications by the T.D. Phillips group. The stability of the aflatoxin-HSCAS complexes mayexplain the in vivo effectiveness of the adsorbent in preventing the toxic effects of aflatoxins inseveral animal species (Pettersson, 2004).Since early studies, HSCAS has been reported to diminish the effects of aflatoxins in a variety ofyoung animals including rodents, chicks, broilers, turkey poults, ducklings, lambs, pigs, minks and74