Aquaculture Europe 2023

September 18 - 21, 2023


Add To Calendar 21/09/2023 10:15:0021/09/2023 10:30:00Europe/ViennaAquaculture Europe 2023BENEATH THE SURFACE: HOW SUB-REGULATORY LEVELS OF FUSARIOTOXINS IN AQUACULTURE FEEDS IMPACT THE HEALTH OF RAINBOW TROUT Oncorhynchus mykissSchubert 1The European Aquaculture Societywebmaster@aquaeas.orgfalseDD/MM/YYYYaaVZHLXMfzTRLzDrHmAi181982


Roy Rosen1,* Pablo Cabo-Valcarce2, Marko Stankovicì3, Michaela Thamhesl1, Manuela Killinger1, Dian Schatzmayr1

1DSM—BIOMIN Research Center, 3430 Tulln, Austria

2Research Center for Animal Nutrition and Health, DSM Nutritional Products, F-68128, Village-Neuf, France

3Institute of Animal Sciences, Faculty of Agriculture, University of Belgrade, 11080 Belgrade, Serbia



The main driver of the Blue Revolution is the potential of modern aquaculture to provide healthy and sustainable protein for the increasing human population. As in the farming of terrestrial animals, the feed used in aquaculture has great bioeconomic importance. Aquaculture feeds in particular are constantly evolving, driven by economic and environmental factors. A major development is the reduction in reliance on raw materials from marine origin which has led to an increased use of globally sourced plant-based raw ingredients, this in turns inherently increased the risk of mycotoxin exposure.

Fusariotoxins are a group of mycotoxins produced by various fungal species of the genus Fusarium. These toxins are among the most prevalent mycotoxins detected globally. The group includes, among others, fumonisins and zearalenone, which are known for their negative effects on sphingolipid metabolism and reproductive-endocrine disturbance, respectively.

European legislation recommends guidance values for certain mycotoxins to ensure food and feed safety and the maintenance of animal welfare. For fumonisins, a 10 mg/kg limit is defined for fish feeds. However, no specific value for zearalenone is defined for this matrix, and a general maximal value of 2 mg/kg (defined for cereal feed materials) is being used de facto as an upper limit.

Unlike other species, few studies describe the effects of sub-regulatory levels of fusariotoxins on salmonids. Two recent studies comprised of three independent in vivo trials, were aimed at addressing this knowledge gap. We assessed the impact of oral exposure to the fusariotoxins fumonisins and zearalenone, below EU guidance levels, on rainbow trout at different developmental stages. The study assessed biomarkers such as metabolites in gut content (in all trials), the sphinganine-to-sphingosine (Sa:So) ratio (in the fumonisins studies), and plasma vitellogenin (VTG) and tissue metabolites (in the zearalenone study). These biomarkers were used as endpoints to evaluate the toxic effects of fusariotoxins and the detoxification efficacy of fumonisins by FumD and zearalenone by ZenA, both of which are commercial feed enzymes designed for specific detoxification.

The results of this study indicate that short-term oral exposure to sub-regulatory levels of fusariotoxins has negative effects on rainbow trout. Commercially available fish feeds that comply with the European regulatory levels may still pose a risk to fish health and farmers’ operations. Thus, the guidance levels should be revised, and further studies should investigate these findings. However, the inactivation of the mycotoxins by feed enzymes FumD and ZenA proved to be an effective strategy to significantly reduce the observed effects in the selected endpoints.