Assessment of Fungal Contamination and Their Toxigenic Potential of Farmed Fish in Western Algeria

Abstract

Fish and fish products have been documented as a major source of pathogens, with fungi playing a key role. In this paper, a survey was conducted to determine the presence of fungi in fish reared in various aquaculture farms in western Algeria, namely Nile Tilapia (Oreochromis niloticus), gilthead sea bream (Sparus aurata) and sea bass (Dicentrarchus labrax). The search for micromycetes was carried out on different parts of the body: skin and flesh, gills, and intestines. A total of 1937 fungal strains were revealed and divided into 10 genera of filamentous fungi, one genus of yeast, and other yeasts that have not yet been determined. Penicillium was the most common genus, representing 41.56% of the fungal population, fol-lowed by Rhodotorula (17.60%), and Aspergillus (15.95%). The greatest number of isolates was identified in the gills of gilthead sea bream, while the lowest number was isolated from sea bass intestines. Secondly, we sought to highlight the toxigenic potential of the fungal strains isolated, using the brine shrimp lethality test. Five of the fungal strains tested, belonging to the two genera Penicillium and Aspergillus, showed toxic potential for Artemia salina. The highest toxicities were observed mainly by strains of Aspergillus parasiticus (APAR001), Aspergillus terreus (ATER002), and Aspergillus niger (ANIG001) respectively. Penicillium chrysogenum (PCHR002) showed the lowest activity. These results confirm the infection of farmed fish by toxigenic fungal communities, which can present a real health hazard to consumers. Regular monitoring and compliance with fish health management practices are recommended.