Effect of Germfree Status on 64 Cu Excretion by the Rat ∗

Abstract

Summary

The fecal excretion of radioactive copper during the first 24 hr following oral dosage was significantly lower in germfree rats than in conventional rats. Urinary excretion of ⁶⁴Cu during the same period of time amounted to approximately 1% of the oral dosage and was not significantly affected by germfree conditions. Growth rates indicated that a mineral level of 120% of the recommended daily allowances for conventional rats was adequate for germfree rats despite the fact that some of the minerals may be metabolized differently by rats in the two environments.