Silver nanoparticles (AgNPs) have recently emerged as a powerful agents for disinfection in the poultry industry. AgNPs are capable of epithelial barriers passing from the route of exposure to the vital organs and cells. This study evaluated the effects of AgNPs on organs weights, blood biochemical, hematological, and coagulation parameters, antioxidant enzyme activities, and histopathological changes and silver concentrations of liver and kidney tissues in laying Japanese quails after exposure to the nanoparticles. The layer quails were randomly assigned to 4 groups, consisting of six replicates, three quails each. The treatments included 0, 4, 8, and 12 mg/L of AgNPs in daily drinking water for 30 weeks. AgNPs decreased the relative weight of liver, ileum and large intestine (P< 0.05). Administration of AgNPs elevated plasma fibrinogen while decreased serum aspartate aminotransferase activity (P< 0.05). The antioxidant status of the liver showed that malondialdehyde level, an end product of lipid peroxidation, was higher (P<0.05) and catalase activity was lower (P<0.05) in the quails exposed to AgNPs. The accumulation of silver in the liver and kidney tissues were increased in a dose-dependent manner after exposure to AgNPs (P< 0.05). Histopathological findings showed reduced lipid vacuolization of hepatocytes in the 12 mg/L AgNPs treatment. In conclusion, the results indicated that AgNPs administration to drinking water can lead to oxidative stress and liver damage in laying quails which may be a predisposing for liver dysfunction.
