The contamination of feed with mycotoxins is a continuing feed safety issue leading to economic
losses in animal production [1]. Consequently, a variety of methods for the decontamination of feed have
been developed, but mycotoxin detoxifying agents seem to be the most promising and are therefore most
commonly used [2,3]. These detoxifying agents can be divided into two different classes, namely
mycotoxin binders and mycotoxin modifiers. These two classes have different modes of action;
mycotoxin binders adsorb the toxin in the gut, resulting in the excretion of complex toxin-binder in the
faeces, whereas mycotoxin modifiers transform the toxin into non-toxic metabolites [4]. The extensive
use of these additives led, in 2009 in the European Union, to the establishment of a new group of feed
additives called mycotoxin detoxifiers. These compounds are specified as “substances for reduction of
the contamination of feed by mycotoxins: substances that can suppress or reduce the absorption, promote
the excretion of mycotoxins or modify their mode of action” [5].
The efficacy of these products has to be evaluated. In vivo efficacy trials are usually based on
so-called unspecific parameters, evaluating animal performance, blood biochemical or hematological
parameters, organ weight, effects on immune function, histological changes, etc. [6]. As these criteria
are non-specific, differences obtained between treated and untreated animals cannot be solely attributed
to the efficacy of the detoxifier. There may be confounding effects involved such as immuno-modulating
activity of β-glucans and antioxidant action of other feed components. A possibility to distinguish
between specific and unspecific effects is the inclusion of a group fed non-contaminated feed
supplemented with the detoxifier. However, the European Food Safety Authority (EFSA) proposed other
end-points based on specific toxicokinetic parameters [7]. As mycotoxin binders are deemed to adsorb
mycotoxins in the gut, a lowered intestinal absorption is expected. According to the EFSA, the most
relevant parameter to evaluate the efficacy of these products is the plasma concentration of these toxins
or their main metabolites. The EFSA proposes short-term feeding trials where the mycotoxin and
detoxifier is mixed in the feed [7]. The plasma concentrations of the mycotoxin, and the main
metabolite(s), should be monitored over a period of at least 5 days with a presampling period of at least
one week (steady-state design). Furthermore, unspecific parameters may be monitored as well. Such
feeding trials are labor and cost intensive. In contrast, a toxicokinetic model where the mycotoxin is
administered with or without mycotoxin detoxifier as a single oral administration would be less
expensive and labor intensive to perform.
The aim of present study was to evaluate a bolus absorption model in relation to the EFSA guidelines,
to study the efficacy of mycotoxin detoxifiers towards the oral absorption of deoxynivalenol (DON)