Effects of Deltamethrin and Endosulfan on the Hepatic Markers and Neurobehavioural Alterations in Japanese Quail ( Coturnix japonica )

Background Deltamethrin (DLM), a synthetic pyrethroid, and endosulfan, an organochlorine pesticide, frequently co‐occur in agricultural environments, yet their combined effects on hepatic function and behaviour in non‐target avian species remain poorly understood. Objectives This study examined the toxic effects of combined DLM and endosulfan exposure on hepatic markers, lipid profile and neurobehaviour in Japanese quail ( Coturnix japonica ). Methods Twelve adult quails were divided into three groups receiving: (1) control, (2) low‐dose (0.1 mg/kg DLM + 0.15 mg/kg endosulfan) or (3) high‐dose (0.4 mg/kg DLM + 0.5 mg/kg endosulfan) via daily oral gavage for 3 weeks. Body and organ weights, serum hepatic and lipid biomarkers and behavioural parameters were assessed. Results The high‐dose group showed a significant reduction in body weight compared with controls, while liver weight remained stable and kidney weights decreased in a dose‐dependent manner. AST (aspartate aminotransferase) and ALP (alkaline phosphatase) were substantially increased in treated groups ( p < 0.05), indicating hepatocellular damage. Lipid profiles showed significant elevations in LDL, VLDL and cholesterol ( p < 0.05). Behavioural assessments demonstrated dose‐dependent effects, including increased agonistic behaviour, reduced locomotor activity and dose‐dependent onset of mucoid faeces (first recorded in Week 1 in the high‐dose group and Week 2 in the low‐dose group, with none observed in controls); foraging behaviour declined sharply in high‐dose birds by Week 3. Conclusions Combined pesticide exposure induces measurable hepatotoxicity, metabolic disruption and neurobehavioural abnormalities in quail at the tested doses. These effects are consistent with DLM‐mediated activation of Na+ channels and endosulfan‐induced blockade of GABA_A receptors.