Effects of selenomethionine and sodium selenite supplementation on meat quality, selenium distribution and antioxidant status in broilers

This study was conducted to investigate the effects of selenomethionine (Se-Met) and sodium selenite (SS) supplementation on meat quality, selenium (Se) distribution, and antioxidant status in broilers. A total of 360 seven-days-old Ross 308 broilers of an average body weight 162 +/- 0.59 g were randomly allotted to three treatments, each of which included three replications of 40 birds. The treatments included a control diet containing 0.04 mg Se/kg and other two diets that contained 0.15 mg Se/kg supplemented by SS or Se-Met. The experiment lasted for 42 days. Selenium supplementation improved (P < 0.05) the Hunter a value of breast muscle in 8 and 16 h and decreased (P < 0.05) the drip loss of breast muscle in 24 and 48 h. Both Se sources and exposed time significantly influenced (P < 0.01) the drip loss of breast muscle. Selenium and glutathione concentrations in serum and in the studied organs were significantly higher (P < 0.05) after dietary Se supplementation while the Se-Met group showed the highest value (P < 0.05). Glutathione peroxidase activity in serum and in the studied organs was also significantly elevated (P < 0.05) by dietary Se supplementation while SS increased the glutathione peroxidase activities in pancreas and breast muscle to a larger extent (P < 0.05) than did Se-Met. The addition of Se from either source caused a significant increase (P < 0.05) in superoxide dismutase activities in tissues (except for kidney) whereas the Se-Met group was more effective (P < 0.05) than the SS group in breast muscle. Selenium supplementation increased (P < 0.05) the total antioxidant capability in serum, liver, kidney and breast muscle while the Se-Met group proved to be more effective (P < 0.05) than the SS group except for kidney. The Se-supplemented diets had a lower (P < 0.05) malondialdehyde concentration in serum and in the studied organs but the effect was more pronounced (P < 0.05) when Se-Met was used except for the serum. These results indicated that Se-Met supplementation was more effective than SS supplementation for depositing Se in serum and tissues, enhancing the antioxidant status and reducing the drip loss of breast muscle.