1. This study evaluated the duodenal wall integrity, antioxidant status as well as some immunological parameters of broiler chickens supplemented with 0.5 g Thymus vulgaris essential oil (EO)/kg diet and 0.4 mg Se/kg DM (dry matter) derived from sodium selenite. 2. A total of 192 one-d-old randomly divided chickens of both sexes (Ross 308 hybrid broilers) were divided into 4 treatment groups of 48 birds each. 3. The first group was fed on a nutritionally balanced basal diet (BD). The other three groups received BD supplemented with 0.5 g/kg thyme oil, or 0.4 mg Se/kg DM, or both feed additives together. 4. The results for the evaluated feed additives were (1) thyme oil - decreased malondialdehyde (MDA) concentration in duodenal mucosa and kidney, increased immunoglobulin A (IgA) concentration in duodenal mucosa, stimulated phagocytic activity in blood, improved intestinal barrier integrity (2) selenium - increased glutathione peroxidase (GPx) activity in blood and liver as well as thioredoxin reductase (TrxR) activity in duodenal mucosa, liver and in the kidney, (3) EO with selenium - increased thioredoxin reductase (TrxR) activity in duodenal mucosa. 5. These results demonstrated that thyme oil alone showed more effective potential to improve intestinal barrier integrity and antioxidant status as well as evoking an immune response in chickens, than if diets were supplemented with both thyme oil and selenium.

ABSTRACT:The objective of this study was to compare the effects of feed supplementation of laying hens with manganese from its inorganic and organic sources on performance and some parameters of egg quality. Ninety-six hens at 20 weeks of age were randomly allocated to 4 dietary treatments, each consisting of 6 replicates (4 birds per replicate). The control group was fed unsupplemented basal diet (BD) with only natural background Mn level of 46.4 mg/kg feed. For the three experimental treatments, the BD was supplemented with 120 mg Mn/kg either from Mn-sulphate or Mn-chelate of protein hydrolysate (Mn-Pro) or Mn-chelate of glycine hydrate (Mn-Gly). After 8 weeks of dietary treatments the egg production, egg weight, feed intake, and feed efficiency were not affected by dietary treatments. Regardless of the sources, Mn supplementation to feed resulted in significantly decreased percentages of cracked eggs compared to the unsupplemented control group. The thickness, weight, proportion, and index of eggshell were significantly elevated in all groups supplemented with Mn. The intake of Mn-Gly resulted in considerably increased Mn deposition in egg yolk compared to the control eggs. In the control and Mn-sulphate groups yolk malondialdehyde (MDA) started to increase after 20 and 30 days of egg storage respectively, whereas in eggs from hens given organic Mn-sources this parameter was not affected up to 40 days. Although there were no significant differences in MDA values between the treatments until 20 days of storage, the Mn-sulphate group showed significantly higher MDA concentration in yolks compared to the control group after 30 days of storage. These results demonstrate that supplementation of hens' diet with Mn has positive effects on eggshell quality. Feed supplementation with Mn from organic sources appears to be more effective in preventing yolk lipid oxidation during cold storage of eggs than that from Mn-sulphate.

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.

<p>The purpose of this study was to compare the effect of dietary zinc from inorganic and organic sources on the concentration of Zn, Cu, Mn and Fe in plasma, tissues and faeces of rabbits. Simultaneously, the activities of total superoxide dismutase (SOD), specific Cu/Zn SOD, glutathione peroxidase (GPx), lipid peroxidation and total antioxidant capacity (TAC) in liver and kidney were also determined. Ninety-six 49-day-old broiler rabbits were allocated to 4 dietary treatments, each replicated 6 times with 4 animals per replicate. For the subsequent 6 wk, the rabbits were fed an identical basal diet (BD) supplemented with an equivalent dose of Zn (100 mg/kg) from different sources. Group 1 (control) received the unsupplemented BD, while the BD for groups 2, 3 and 4 was supplemented with Zn from Zn sulphate, Zn chelate of glycine hydrate (Zn-Gly) and Zn chelate of protein hydrolysate (Zn-Pro), respectively. The intake of dietary Zn sulphate resulted in an increase in Zn plasma concentration (1.85 vs. 1.48 mg/L; <em>P</em>&lt;0.05) compared to the control group. Feeding the diets enriched with Zn increased the deposition of Zn in the liver (<em>P</em>&lt;0.05), irrespective of the Zn source. The addition of Zn-Pro resulted in significantly higher Cu uptake in liver (<em>P</em>&lt;0.05) than in the control and Zn sulphate group (56.0 vs. 35.0 and 36.7 mg/kg dry matter (DM), respectively). Neither Mn nor Fe concentration in plasma and tissues were affected by dietary Zn supplementation, with the exception of Fe deposition in muscle, which was significantly decreased (<em>P</em>&lt;0.05) in rabbits supplemented with inorganic Zn sulphate compared to control and Zn-Gly group (9.8 vs. 13.3 and 12.2 mg/kg DM, respectively). Intake of organic Zn-Gly significantly increased the activities of total SOD (43.9 vs. 35.9 U/mg protein; <em>P</em>&lt;0.05) and Cu/Zn SOD (31.1 vs. 23.8 U/mg protein; <em>P</em>&lt;0.01) as well as TAC (37.8 vs. 31.2 μmol/g protein; <em>P</em>&lt;0.05) in the kidney when compared to that of the control group. The presented results did not indicate any differences between dietary Zn sources in Zn deposition and measured antioxidant indices in rabbit tissues. Higher dietary Zn intake did not cause any interactions with respect to Mn, Cu and Fe deposition in liver and kidney tissues, but did increase the faecal mineral concentrations. Dietary organic Zn-Gly improved the antioxidant status in rabbit kidney.</p>