Recovery of Radioactive Chromic Oxide from the Bovine Gastrointestinal Tract

Abstract
Six Aberdeen Angus heifers were confined to metabolism crates and orally dosed with approximately 146 µCi of 51Cr2O3 to determine whether chromic oxide was absorbed from the bovine gastrointestinal tract. No radioactivity was detected in the blood or urine. Fecal excretion patterns of 51Cr2O3 were established for each individual animal. An average of 87.2% of the orally dosed 51Cr2O3 was recovered in the feces by 216 hours. Ninety-eight percent of the ingested unlabeled chromic oxide was recovered in the feces as measured by chemical analyses. Coefficients of digestibility were not different (P > 0.05) when calculated by total collection methods compared with the chromic oxide ratio technique.