Protective effects of Opoka mineral clay against imidacloprid toxicity in juvenile Nile tilapia ( Oreochromis niloticus ): hematological, biochemical, and histopathological insights

Abstract

Pesticide contamination poses a significant threat to the sustainability of aquaculture, particularly affecting Nile tilapia (Oreochromis niloticus), a key species for global food security. This study evaluated the protective efficacy of dietary Opoka mineral clay against imidacloprid (IMI)-induced toxicity. Ninety juvenile Nile tilapia (50 ± 12 g) were randomly assigned to six treatments (n = 15): control (basal diet), 2% Opoka, 4% Opoka, IMI (14 mg/L), 2% Opoka + IMI, and 4% Opoka + IMI for 30 days. IMI exposure led to increased IMI muscle residues, oxidative stress, hematobiochemical alterations, growth suppression, and multi-organ histopathological damage (p < .05). Co-supplementation with Opoka, particularly at 2%, significantly reduced IMI residues (~70% reduction), restored redox balance, improved physiological parameters, enhanced growth performance, and preserved tissue architecture. These findings demonstrate that low-dose Opoka supplementation is an effective, natural strategy to mitigate neonicotinoid toxicity in Nile tilapia aquaculture.