Abstract
Two experiments were conducted to evaluate the efficacy of inorganic Se, as sodium selenite, or three organic Se sources (fish meal, brewers grains, distillers grains and solubles) on the Se status in young pigs during a 35-day post-weaning period. Inorganic and organic Se contributed from brewers grains or distillers grains and solubles resulted in similar weekly serum Se response curves within each Se level with 4-week old weanling swine while Se contributed by fish meal had lower levels. Serum Se was considered low and did not rise substantially above initial weanling levels when .1 ppm was fed from either inorganic or organic Se sources, whereas it did rise when the .4 ppm concentration was provided. At the .4 ppm added level, muscular (heart, longissimus) tissue Se concentrations were greater when fish meal or brewers grains were fed as compared to the selenite source, whereas non-muscular tissue (liver, kidney, testis) had similar Se concentrations for all groups. Fish meal was considered to provide the poorest Se retention of all test products evaluated. Growth rate was not an adequate criteria to evaluate Se adequacy in pigs fed practical diets. These results suggested that .1 ppm Se was not adequate to meet the young weanling pig's Se requirement. At 52 kg tissue Se concentrations in pigs fed selenite or the organic Se sources during the post-weaning period were greater than if it had not been included in the earlier phase. Copyright © 1978. American Society of Animal Science . Copyright 1978 by American Society of Animal Science.