Authors: Dr. Amit Patra, Jesse Stoops, Kurt van de Mierop

Mycotoxins are toxic substances originating from the secondary metabolism of different types of fungi such as Fusarium, Aspergillus and Penicillium.  Mycotoxins are produced by fungi growing on crops in the field or during the storage of vegetable ingredients. Although the prevalence of mycotoxins can be region-specific due to climate and post-harvest storage conditions, mycotoxins can contaminate a wide array of crops andare a worldwide problem.

MOST IMPORTANT MYCOTOXINS

Among hundreds of known mycotoxins, aflatoxins (AFs), ochratoxin A (OTA), fumonisins (FBs), zearalenone (ZEA) and trichothecenes (DON, T-2, HT-2) are considered the major mycotoxins in animal production. The variety of clinical effects caused by mycotoxins after ingestion ranges from reduced performance, suppressed immune function, organ damage, reduced gut health and nervous and reproductive system problems and depend on the type of mycotoxin, its dosage and the animal species. Significant economic losses are associated with mycotoxins due to their impact on animal performance.

SYNERGY

Contamination of raw materials with more than one mycotoxin often occurs as a given fungi can produce several kinds of mycotoxins. Furthermore, multiple mycotoxin contamination in complete feed is even more likely as animal feed contains several types of raw materials. The presence of multiple mycotoxins can generate additive or synergistic effects, making the negative effect on health and production bigger than the sum of the individual effects. In addition, chronic exposure to low concentrations of mycotoxins results in non-specific symptoms which are difficult to track-and-trace down to mycotoxins. Consequently, the ingestion of multiple low-dose mycotoxins can result in more severe negative effects on animal performance and larger economic losses than an acute toxic dose.

Modified Mycotoxins

Modified mycotoxins are derivatives of mycotoxins produced by fungi or formed by infected plants as part of their defense mechanism. In addition, the formation of these derivatives can also occur by feed production processes and by microbial metabolism. Once ingested with the feed, the modified mycotoxin can be reconverted to the parent toxin by the microbiota and metabolism of the animal.  Modified mycotoxins often exhibit a similar toxicity as their parent toxins, but can also be less or even more toxic than their parent toxin.  Modified mycotoxins are problematic as they are hidden from many analytical detection methods, leading to an underestimation of the contamination level of the feed.

SAMPLING

As mycotoxins cause diverse toxic effects on animals, it is important to adopt good management and control practices to reduce their impact. These practices include correct sampling, fast and reliable analysis methods and taking appropriate measures based on the results. Sampling is one of the most crucial, but underestimated parts of the detection. Mycotoxins are not distributed homogeneously in the raw materials. Therefore, if representative samples are not taken from different parts of the bulk, the results will very possibly be negative for mycotoxins, generating a false sense of security.

What makes a good mycotoxin binder?

Nowadays, the market is overflowing with commercial toxin binders, each marketed with their own physiochemical and biological properties. This can lead to confusion about choosing the appropriate product. Considering the following criteria will contribute to making an informed decision when evaluating the many available binders.

Reducing the bio-availability of the mycotoxins by use of substances that can reduce the absorption and promote excretion of mycotoxins, is the most efficient approach to reduce the adverse effects of mycotoxins on production animals. Broad spectrum mycotoxin binders with a high retention capacity in gastrointestinal conditions (acidic and neutral pH) are crucial to counteract the effects of mycotoxins. In addition, the specificity to the mycotoxin binder is essential to avoid the binding of nutrients and an efficient mycotoxin binder should be able to adsorb mycotoxins even when their contamination level is low. Lastly, mycotoxin adsorbing agents should have a high stability and should be safe for animals, consumers and the environment.

Free-Tox –  the polyvalent mycotoxin binder

To help feed mills and farmers in dealing with the challenges of unpredictable and difficult to control mycotoxin contaminations, Nutrex developed the Free-Tox product range after extensive research combining in vitro and in vivo trials across various species. The Free-Tox brand covers a variety of products, ranging from binders composed only of various carefully selected silicate based components to more complex products with more diverse ingredients that act synergistically to prevent and counter the negative impact of mycotoxin contamination.

References available on request

Authors :

Dr. Amit Kumar Patra, M.V.Sc – Nutrex nv

Jesse Stoops – Nutrex nv

Kurt Van de Mierop, MSc – Nutrex nv