Mycotoxins are feed contaminants produced by certain species of fungi on crops and stored commodities used as ingredients or feed for animals. These contaminants are well-known in the livestock industry and their effects such as feed refusal, weight loss and immune suppression have been well-investigated in terrestrial farm animals. Only lately, because the inclusion and variety of plant-based ingredients in fish feeds are increasing, there is a growing awareness of mycotoxin contamination in the aquaculture industry.
This thesis explored the impact of mycotoxins on the performance and health of rainbow trout (Oncorhynchus mykiss) in aquaculture. First, a survey assessed mycotoxin contamination patterns in feed ingredients and aquafeeds. Based on the survey results, deoxynivalenol (DON) was selected as the toxin of interest for this thesis. Secondly, a series of three in vivo studies were set up to investigate the effects of DON in rainbow trout and assessed if DON effects would change with potential co-factors (e.g., time, diet composition, and co-exposure to other toxins).