In vitro Uptake of Selenium-75 by Red Blood Cells from the Immature Ovine during Varying Selenium Intakes

Abstract

Six crossbred wether lambs were used for preliminary study of the effect of varying Se intake upon uptake of 75Se in vitro by ovine red blood cells. In a second experiment, 16 crossbred wether lambs were equally allotted among 4 dietary Se levels of 0.014, 0.264, 0.514 and 5.014 ppm. The feeding trial lasted 104 and 107 days for experiments 1 and 2, respectively. Lambs receiving 0.264 and 0.514 ppm Se gained faster, consumed more feed and had a higher feed efficiency than lambs in other dietary groups. Lambs on 0.014 ppm Se performed better than with the 5.014 ppm level. Adequate vitamin E may have prevented deficiency syndromes in lambs fed the low level of Se. Two lambs on the 5.014 ppm level exhibited symptoms of chronic selenosis. The uptake of 75Se was significantly correlated with incubation time in the presence of an O2-CO2 mixture. The initial influx and rate of in vitro uptake of 75Se by ovine blood cells decreased with increasing Se level in the diet. The in vitro uptake of 75Se by red blood cells proved to be a promising technique to assess the nutritional Se status in the immature ovine.