Maternal transfer of selenium by blood and milk in camel

Ten pregnant female camels divided into two groups received after a 2 weeks adaptation period, an oral selenium (Se) supplementation (0 and 2 mg respectively) under sodium selenite form for 6 months from the three last months of gestation up to the three first months of lactation. Feed intake was assessed daily. Blood samples and body weight were taken on a bi-weekly basis, both in dams and their camel calves after parturition. Milk was collected at birth (colostrum), then on a bi-weekly basis. The Se concentration in serum increased significantly in the supplemented group and was threefold higher than the concentration compared to the control group, respectively 305.9 ± 103.3 ng/mL and 109.3 ± 33.1 ng/mL. Blood values in camel calves were similar to those of the dams. In calves, Se values were 106.3 ± 26.5 and 273.2 ± 48.0 ng/mL in the control and treated groups respectively. The selenium concentration increased in similar proportion in milk (86.4 ± 39.1 ng/mL in the control group vs 167.1 ± 97.3 ng/mL in treated group). In the colostrum, Se concentration was higher in the both groups, but with similar difference: it was threefold higher in treated group with a mean value 302 ± 94.60 vs 108.2 ± 43.9 ng/mL. The gluthathione-peroxidase (GSH-Px) activity in dams varied between 18.1 ± 8.7 in control group and 47.5 ± 25.6 IU/g Hb in treated group but decreased after parturition in both groups. At parturition, the camel calves born from supplemented dams had GSH-Px values threefold higher than the control calves: 73.8 ± 2.9 vs 25.0 ± 3.2 IU/g Hb (P<0.001). Vitamin E did not change significantly and was on average 1.17 ± 0.72 ng/mL and 1.14 ± 0.89 ng/mL in the control and treated group respectively. The mean value for camel calves in the control group was 0.65 ± 0.49 vs 0.82 ± 1.08 ng/mL in the treated one. Significant correlations were reported between mother serum Se, camel calf serum Se, milk Se and GSH-Px both in dams and calves. The results confirm the sensitivity of camel to Se supplementation with an important increase of selenium in serum and milk, allowing protection of camel calf against Se deficiency, commonly observed in Emirates. (Texte intégral