Protective Effect of Ethoxyquin and N-acetylcysteine on Biochemical and Pathological Changes Induced by Chronic Exposure to Aflatoxins in Laying Hens

Aflatoxins (AFs) represent a major threat to poultry health and food safety due to their hepatotoxic, immunosuppressive, and carcinogenic effects. This study evaluated the chemoprotective potential of ethoxyquin (EQ) and N-acetylcysteine (NAC) in laying hens (80.8 and 33.3 mg/kg BW/d) exposed to chronic dietary AFs contamination (0.0-1.5 mg/kg). A total of 360 Hy-Line W36 Leghorn hens were monitored over 72 weeks using biochemical and histopathological analyses of liver and kidney tissues. NAC significantly (<i>p</i> < 0.01) increased hepatic and renal levels of reduced glutathione (GSH) and stimulated glutathione S-transferases (GST) and gamma-glutamyl transferase (GGT) activity, enhancing detoxification. Both agents significantly (<i>p</i> < 0.05) reduced plasma ALT and AST levels, preserved total protein concentrations, and attenuated liver and kidney hypertrophy. EQ demonstrated antioxidant effects, stabilizing enzymatic responses and limiting tissue damage. Histopathological analysis revealed fewer structural alterations and cellular degeneration, especially in the NAC-treated group (<i>p</i> < 0.01). These results suggest that NAC and EQ activate endogenous detoxification mechanisms, both enzymatic and non-enzymatic, effectively mitigating chronic aflatoxin toxicity. Their dietary supplementation offers a safe and sustainable chemoprotection strategy to support poultry health and productivity, particularly in regions facing high mycotoxin exposure.