Effects of supplemental selenium on swine. I. Gestation and lactation.

Effects of two levels of dietary selenium (se) on reproductive performance and blood Se status of mature gestating and lactating sows were evaluated over one reproductive cycle. Four groups of six Duroc sows were fed basal corn-soybean meal (SBM) or corn-SBM-tankage diets each with or without .1 ppm supplemental Se. The basal diets contained .1 ppm natural Se. Changes from the 28th day of gestation through the 56th day of lactation in whole blood and plasma Se concentrations and in vitro red blood cell (RBC) 75Se uptake indicated greatest demand for Se came immediately after parturition but treatment differences (P<.05) were evident only at the l l 2 t h day of gestation and 28th day of lactation. At the 28th day of lactation, the Se supplemented sows had higher plasma (P<.05) and whole blood (P<.01) Se concentrations than the unsupplemented sows. Reproductive performance was not affected by treatment (P<.05). (