TY - JOUR AU - Mohamed, Hams M.A. AU - Emeish, Walaa F.A. AU - Braeuning, Albert AU - Hammad, Seddik PY - 2017/12/13 Y2 - 2024/03/29 TI - Detection of aflatoxin-producing fungi isolated from Nile tilapia and fish feed JF - EXCLI Journal JA - EXCLI J. VL - 16 IS - 0 SE - Original articles DO - 10.17179/excli2017-960 UR - https://www.excli.de/index.php/excli/article/view/302 SP - 1308-1318 AB - <p>Contamination of fish by fungi and their mycotoxins poses major health concerns to human and animals. Therefore, our study was aimed to investigate <i>Aspergillus flavus (A. flavus)</i> infections and the levels of aflatoxins in Nile tilapia, <i>Oreochromis niloticus (O. niloticus)</i>, and fish feed. Samples from <i>O. niloticus</i> and fish feed (n=25 for each) were randomly collected from private fish farms at Qena province, Egypt, during the winter season. Different<i> Aspergillus</i> spp. were detected in 60 % and 64 % of <i>O. niloticus</i> and fish feed, respectively. HPLC-based analysis revealed aflatoxin-producing activity in 75 % and 83 % of <i>A. flavus</i> isolates from fish and fish feed, respectively. While 96 % of <i>O. niloticus </i>muscles and fish feed samples were contaminated with aflatoxins, the detected levels were below the permissible limits, i.e. 20 µg/kg. Moreover, experimental infection with toxicogenic <i>A. flavus</i> isolates was conducted to evaluate their pathogenicity in<i> O. niloticus</i>. Expectedly, experimental infections of <i>O. niloticus</i> with <i>A. flavus</i> were associated with several clinical symptoms reported in naturally infected fish, e.g. yellow coloration with skin ulceration, hemorrhagic ulcerative patches on gills and skin, corneal opacity, fin rot and abdominal distention. Furthermore, aflatoxicogenic<i> A. flavus</i> isolates from fish were sensitive to herbal clove oil. Even though the measured levels of aflatoxin were below permissible limits, effort should be placed on further reduction of exposure to genotoxic and carcinogenic mycotoxins.</p> ER -