Protective effects of dietary Lavender (<i>Lavandula officinalis</i>) essential oil against Malathion-induced toxicity in rainbow trout (<i>Oncorhynchus mykiss</i>)

Abstract The present study was aimed to evaluate the moderating properties of lavender ( Lavandula officinalis ) essential oil (LEO) against immunotoxic effects organophosphate pesticide, malathion in rainbow trout, Oncorhynchus mykiss . For this purpose, fish were supplemented with LEO at dietary concentrations 0.5, 1, 2 and 4 ml/kg diet for 56 days. A non-LEO group also considered as control. After 57 days feeding trial, biochemicals assayed blood kidney tissue then exposed a sub-lethal concentration [0.24 mg/l equal 30% LC 50 (0.8 mg/L)]. serum total immunoglobulin, respiratory burst activity, lysozyme activity complement significantly elevated treated 1 ml LEO/kg compared individuals (P&lt;0.01). Such changes not observed (P&gt;0.01). Significant elevations expression immune genes (iNOS C 3 genes) 0.2–2 mg non-supplemented ones decreased fed exposure malathion, all components declined control those In contrast, immunity exhibited no significant after iNOS reduced response (P&lt;0.05). Furthermore, these showed findings suggested an immunoprotective role optimized oxidative stress toxicity induced by malathion. Nevertheless, high (4 diet) had reducing on immunity.