Ameliorative pharmacological effects of dietary Chlorella vulgaris and β-glucan on chlorpyrifos-induced oxidative stress, immunomodulation, and growth performance in African catfish (Clarias gariepinus)

This study evaluated the chronic sublethal toxic effects of chlorpyrifos on growth performance, oxidative status, and immune function in African catfish (Clarias gariepinus). A total of 180 fish (21.8 ± 1.15 g) were allocated into four groups—control, CPF (0.24 mg/L; 1/10 of the 96-h LC₅₀), CPF + CV (2%), and CPF + β-glucan (0.1%)—for 60 days. CPF exposure markedly elevated hepatic enzymes, uric acid, creatinine, and MDA, while antioxidant enzymes (SOD, GSH) and immune indices (IgM, CRP, respiratory burst, lysozyme) declined. Both CV and β-glucan mitigated these adverse effects: CV yielded the best growth and survival, and β-glucan produced stronger antioxidant recovery. Additionally, CPF upregulated TNF-α and downregulated IL-10 gene expression in spleen tissues; both additives normalized these cytokines. Overall, dietary CV (2%) and β-glucan (0.1%) effectively counteracted CPF-induced oxidative stress, immunosuppression, and growth retardation in C. gariepinus, supporting their inclusion as protective nutraceuticals in aquafeeds.