Effects of dietary aflatoxin B(1) on accumulation and performance in matrinxã fish (Brycon cephalus)

Aflatoxins (AF) can be cumulative in fish tissues and can influence weight, length, feed intake and survival depending on the species. The aim of this work is to measure performance and aflatoxin levels in tissues of matrinxã (Brycon cephalus) fish chronically exposed to aflatoxin. Aflatoxin was incorporated into fish diets at the following levels: Control Feed + 0 μg AFB(1) kg(-1); A. Feed + 10 μg AFB(1) kg(-1); B. Feed + 20 μg AFB(1) kg(-1); C. Feed + 50 μg AFB(1) kg(-1). It was used one tank per treatment, each one with 150 juvenile fish, and three replicates within each tank were used for sampling, that was carried out monthly over a period of six months. Aflatoxin was quantified by HPLC in fish liver and muscle after clean up using immunoaffinity columns. Performance was evaluated by using weight, length, consumption and survival rate. Muscle and liver aflatoxin levels were below the limit of detection in all control samples. Aflatoxins B(2), G(1) and G(2) were not detected in any tissues. Traces (values between limits of detection and quantification) of AFB(1) were observed in liver tissue in treatment A from day 30 through 90, reaching 0.32 μg AFB(1) kg(-1) at 150 days of exposure. Treatment B presented traces up to day 60 and had, with a maximum level of 0.39 μg AFB(1) kg(-1) at 150 days of exposure. Treatment C had aflatoxin residues after day 30, with values ranging from 0.17 to 0.61 μg AFB(1) kg(-1) during exposure. Muscle samples only had traces of AFB(1) in all treatments. Fish was affected by exposure to AFB(1) with higher values (P<0.05) for weight and length in treatments A, B and C relative to controls. Therefore, results indicate that matrinxã do not accumulate AFB(1) residues in edible tissues, but chronic exposure affects the species.