Effect of Mineral Supplementation on the Selenium Concentration and Glutathione Peroxidase activity in Cattle and Camels

Five camels and 5 cows were fed with a similar basal diet for six months. They received oral trace element supplementation for 3 months (day 22-112). The supplementation included zinc, copper, selenium, manganese, iodine and cobalt, and corresponded to twice the daily requirement generally recommended for cows. Plasma selenium concentration was significantly lower in the camels (20 ± 2 ng/ml) as compared the cows (37 ± 2 ng/ml). The mineral supplementation induced an important increase in the plasma selenium concentration in camels which reached 220 ± 35 ng/ml. However, for the cows, the increase was very low and did not overreach 65 ± 8 ng/ml. The red blood cell glutathione peroxidase activity was similar in the camel and the cow and varied between 4000 and 6000 IU/100 g hemoglobin. In both species, this activity increased with mineral supplementation and stayed very high even when mineral supplementation was stopped. The results suggested that selenium metabolism in camels is different from that in the cows.