Ask the author: Mycotoxin risk in aquafeeds

Those are the latest findings according to a recent paper on the occurrence of mycotoxins in commercial aquafeeds in Asia and Europe, written by several Biomin authors, that was published in Reviews in Aquaculture, a scientific journal. These results were also discussed at the recent Biomin Aqua Days. Rui Gonçalves, scientist aquaculture at Biomin, explains the significant of the findings for the aquaculture industry.

What is the importance of this study for the aquaculture industry? What new information or insight does it offer on mycotoxins?

Gonçalves: “The risk to terrestrial livestock is already fairly well-documented. During these last years we have seen an increasing awareness of the negative effects of mycotoxins in aquatic species. As plants proteins continue to replace fishmeal, the chance of mycotoxin contamination increases. Scientific research on the adverse effects of mycotoxins on aquatic species continues to advance, furthering our understanding of the topic. We know that these effects vary greatly depending on a variety of factors including nutritional and health status prior to exposure, dose and duration of exposure, age, species and infection route. However, until now no one had correlated the presence of mycotoxins in aquaculture feeds to the sensitivity levels of the aquatic species reported in scientific literature. Our paper shows that mycotoxin levels can be a real cause for concern. It’s something the industry needs to take into consideration in light of the implications for health, performance and profitability.”

How well do we understand the threat that mycotoxins pose to farmed species?

“As research continues, we develop a clearer picture. The wide variety of farmed species raises the time and investment required to have the full story. One thing that we emphasised is that the effects of mycotoxins on farmed species that we covered are probably underestimated. This because of three major factors:

1. The number of studies conducted per species,
2. The variety of farmed species raised in very distinct environments and with distinct characteristics, makes almost impossible to transpose results from one specie to another, even if they are quite close phylogenetic speaking, and
3. The fact that most research looks at the effect of a single mycotoxin, whereas hundreds of distinct mycotoxins and metabolites have been identified.

Various fungi produce mycotoxins during the production and storage of crops, and mycotoxins tend to occur in groups. Some mycotoxins are known to demonstrate synergistic effects, meaning that they aggravate the harm to animals even at low levels. It’s these more realistic scenarios where further research is needed.”

Why is it so important to focus on the co-occurrence of mycotoxins?

“Considering the fact that compound feed contains a mixture of several raw materials, each of them with their own mycotoxin contamination pattern and the fact that mycotoxigenic fungi are usually capable of producing more than one mycotoxin, the presence of multiple mycotoxins is quite high. We observed that 76% of the samples collected had two or more mycotoxins. We would expect that some mycotoxins act synergistically in fish and shrimp, as shown in other animals. That would mean, for example, that the sensitivity levels of a given species is actually much lower than the current figures.”

What future developments do you expect on the topic of mycotoxins in aquaculture?

“We will see research shift towards conditions that more closely match real-world aquaculture production. As our knowledge of mycotoxins in aquaculture grows, it will become even more useful to the industry. At Biomin, we have nearly three decades of experience delivering top notch mycotoxin risk management to customers throughout the world. We will continue to support the aquaculture industry in this way, and I would expect that we expand key efforts as time goes on.”

How does it feel to be involved in mycotoxin research for aquaculture at Biomin?

“Biomin has an excellent team working on this topic. Personally, it is very motivating to be part of such a group. There is still so much to do regarding mycotoxin research in aquaculture and that’s the most motivating thing about it.”