Effect of Pre- and Postpartum Selenium Supplementation in Sheep

In this study, the effect of pre- and postpartum Selenium (Se) supplementation on Se levels of the allantoic fluid, colostrum, milk and plasma as well as on the body weight gain of ewes and their newborn lambs was investigated. A total of 32 pregnant primiparus Pelibuey ewes were selected and classified randomly into 3 groups. The 1st group received Subcutaneous (SC) Se supplementation with 0.1 mg of sodium selenite/Kg BW at 7th, 4th week prepartum and 1st week postpartum. The 2nd group was treated with oral Se supplementation 3 mg of sodium selenite/head/week, for 7 weeks prepartum, while the 3rd group remained as a control, without Se supplementation. Maternal plasma samples were collected weekly for 8 weeks pre- and postpartum and at parturition, while samples of the allantoic fluid were collected for 5 weeks prepartum. Plasma samples of the newborn lambs were collected at 48 h of the age and weekly for 8 weeks. Samples of colostrum and then that of the milk were collected weekly for 8 weeks for determination of Se levels. The body weight of the lambs born to the SC Se supplemented ewes was higher than that of the control (p < 0.05) group for the first 2 weeks postpartum. Allantoic fluid, colostrum, milk, maternal and lamb plasma Se concentrations were significantly increased in Se supplemented groups than that of the control (p < 0.05). Positive relationships were observed between gestational age and Se concentration of the allantoic fluid (r = 0.92- 0.96; p < 0.05) and between milk and lamb plasma Se concentration (r = 0.57- 0.73; p < 0.05). Positive relationships were also detected between maternal plasma and milk Se concentration (r = 0.66-95; p < 0.05) in Se supplemented groups, while negative relationship occurred in the control group (r = - 0.60; p < 0.05). Milk and lamb plasma Se concentrations were higher in the SC group than that of the oral group (p < 0.05), for the first 2 weeks postpartum. Prepartum sodium selenite supplementation was important to maintain the maternal plasma Se level during gestation and postpartum Se supplementation was important for maintaining milk and lamb plasma Se concentrations and improving the body weight gain of the newborn lambs. Allantoic fluid changes were confirmed as a good indicator of fetal Se status and may act as storage of Se and play a role in Se metabolism between the dam and fetus.