Deoxynivalenol and Fumonisin B1 in Gilthead Seabream Diets: Impact on Growth Performance, Hematology, Immunology, and Histopathology.

As aquafeed formulations include more plant-based materials, mycotoxin contamination is becoming relevant for fish farming. Deoxynivalenol (DON) and fumonisin B1 (FB1) frequently occur in fish feeds and may impair fish performance and health. This study evaluated the impact of DON and FB1 on growth and health parameters in gilthead seabream (Sparus aurata). Fish were fed ad libitum for seven weeks with six diets assessed in triplicate: DON A (300 ppb), DON B (2000 ppb), DON C (5000 ppb), FB1 A (5 ppb), FB1 B (10 ppb), FB1 C (40 ppb). The highest contamination levels significantly reduced feed intake, body weight, total length, and biomass, while body weight was also reduced in the lowest FB1 treatment. The feed conversion ratio increased in exposed fish, whereas the specific growth rate decreased in DON B, DON C, FB1 A, and FB1 C. Both mycotoxins altered hematological profiles, immune-related enzymatic activities, and liver morphology. DNA damage increased with exposure level and was greatest at the highest DON concentration. Overall, this study shows that short-term dietary exposure can impair seabream performance and health, supporting stricter mycotoxin monitoring in fish feeds and research on chronic exposure, recovery, and species-specific safety thresholds.