Effect of dietary Salvia officinalis essential oil and sodium selenite supplementation on antioxidative status and blood phagocytic activity in broiler chickens

Selected indicators of the antioxidant status and blood phagocytic activity were investigated in broiler chickens fed diets enriched with essential oil from Salvia officinalis and/or sodium selenite for 5 weeks. Twenty four one-day-old Ross 308 hybrid broilers were randomly divided into four groups according to dietary treatments. The control group was fed unsupplemented basal diet, whereas the feeds of three treatment groups were supplemented with essential oil (0.05%), sodium selenite (0.4 mg Se/kg dry matter) or their combination, respectively. The intake of diets containing essential oil alone or together with Se significantly elevated (P < 0.05) the total antioxidant status in plasma. The combination of essential oil and sodium selenite added to the basal diet resulted in significant reduction (P < 0.05) of superoxide dismutase activity in erythrocytes, increased activities of glutathione peroxidase in liver (P < 0.001) and duodenal mucosa (P < 0.05) compared to the control. Higher malondialdehyde concentrations in kidney tissues (P < 0.01) of chickens supplemented with sodium selenite were reduced by addition of essential oil to their diet. Blood phagocytic activity was significantly (P < 0.001) increased in both groups supplemented with selenium. The presented results demonstrate that Salvia officinalis essential oil and sodium selenite jointly added to diets had a more positive effect on the antioxidant status of broilers than when both additives were administered separately.