Mycobiota and aflatoxin B1 in feed for farmed sea bass (Dicentrarchus labrax)

Abstract

The safety characteristics of feed used in fish and crustacean aquaculture systems are an essential tool to assure the productivity of those animal exploitations. Safety of feed may be affected by different hazards, including biological and chemical groups. The aim of this preliminary study was to evaluate fungi contamination and the presence of aflatoxins in 87 samples of feed for sea bass, collected in Portugal. Molds were found in 35 samples (40.2%) in levels ranging from 1 to 3.3 log10 CFU·g-1. Six genera of molds were found. Aspergillus flavus was the most frequent, found in all positive samples, with a range from 2 to 3.2 log10 CFU·g-1. Aspergillus niger was found in 34 samples (39.1%), ranging from 1 to 2.7 log10 CFU·g-1. Aspergillus glaucus was found in 26 samples (29.9%) with levels between 1 and 2.4 log10 CFU·g-1. Penicillium spp. and Cladosporium spp. were both found in 25 samples (28.7%). Fusarium spp. was found in 22 samples (25.3%), ranging from 1 to 2.3 log10 CFU·g-1. All feed samples were screened for aflatoxins using a HPLC technique, with a detection limit of 1.0 μg·kg-1. All samples were aflatoxin negative. © 2011 by the authors; licensee MDPI, Basel, Switzerland.