Mitigating Potential of Garlic and Turmeric in Aflatoxin-Contaminated Feeds of Oreochromis niloticus

Abstract

Fish feed contamination by mycotoxins presents serious challenges to farmers, as consuming aflatoxin-contaminated feed can result in toxin accumulation in fish, potentially posing risks to human health. This study assessed the detoxifying effects of garlic and turmeric powders on mycotoxin-contaminated feed and their impact on the growth and haematological parameters of juvenile Oreochromis niloticus (17.18±0.798g). Conducted in circular concrete tanks (0.5 m deep and 0.58 m in diameter), the experiment involved eight treatments (TDs) with three replicates each: TD1 (mold-free feed), TD2 (feed contaminated with Aspergillus flavus mould), TD3 (20 g garlic/kg contaminated feed), TD4 (40 g garlic/kg contaminated feed), TD5 (60 g garlic/kg contaminated feed), TD6 (20 g turmeric/kg contaminated feed), TD7 (40 g turmeric/kg contaminated feed), and TD8 (60 g turmeric/kg contaminated feed). Feeding trials spanned ten weeks to evaluate the effects of garlic and turmeric in mitigating aflatoxin impacts on fish growth and nutrients utilization. Some of the key findings are: Aflatoxin levels in analyzed feeds before (2.6448 µg/kg) and after (123.168 µg/kg) the inclusion of Aspergillus flavus varied. Feed processing methods, such as pelleting and drying, reduced aflatoxin concentrations. Significant differences (P>0.05) were observed in fish final weights and weight gain across treatments, with TRT 6 yielding the highest weight (16.07 g). Fish fed with TRT 1 (10.90 g) and TRT 6 (10.98 g) demonstrated the best feed intake responses. Though pelleting and drying contributed to reducing aflatoxin levels, aflatoxins did not necessarily impact protein efficiency ratio (PER), nor did garlic and turmeric significantly enhance it. The inclusion of garlic and turmeric showed an improved nutrients utilization in Oreochromis niloticus despite the presence of aflatoxins in the feed.