OLMIX SURVEY 2016: THE NATURAL CO-OCCURRENCE OF MYCOTOXINS IN FEEDSTUFF

Raquel T. Pereira, Maarten J. van Schoonhoven, Maria A. Rodriguez
 
Olmix Group
Technical Service South America
São Paulo, Brazil rpereira@olmix.com
 

There is an increasing trend to use more and more plant ingredients in aquaculture feeds. And with it the risk of mycotoxin contamination also increases. These toxins are produced as secondary metabolites by fungi and can have serious detrimental effects on fish and shrimp. Ranging from mortalities in severe cases, to economic impacts such as reduced growth, reduced immunity, decreased feed efficiency. They can be caused by a single mycotoxin, or as is more common, by more mycotoxins working together synergistically causing even more damage. The contamination of raw materials is common under certain environmental conditions such as humidity, temperature and presence of insects. Accurate measurement of concentration of mycotoxins in the feed is difficult to determine due to its heterogeneous distribution. A representative sample is the accumulation of small portions (sub-samples) from many different locations over and around of the feed heap.

The natural co-occurrence of fungal metabolites in feed ingredients sampled from 42 different countries (Europe, Asia and South America) was studied using an LC-MS/MS based multi-mycotoxin method, between 01/2013 to 31/2016. All analyzed maize samples were found to be contaminated by different mycotoxins. Polycontamination was found in 82% of the tested samples (49% of the samples were contaminated with 2 - 5 mycotoxins, 32% with 6 - 10 and 2% with > 10 mycotoxins). Only in 5% of the samples no mycotoxins were found. Prevention of mycotoxin formation through agricultural practices in the field is becoming of paramount importance. Moreover, due to its dynamic nature, the potential presence of fungal metabolites from the field and/or feedstuff storage is variable, innovative strategies with a wide spectrum to deal with mycotoxin risk in aquaculture feed is strongly recommended.