The copper metabolism of warm-blooded animals with special reference to the rabbit and the sheep

Abstract

Groups of rabbits were fed for 12 weeks on the same diet at two levels of copper intake (8.5 and 30 p.p.m. Cu). There was no real increase in the liver copper levels at the higher copper intake. When rabbits were injected intravenously with 1 mg Cu, the excess copper was eliminated from the liver in 96 hr. Some copper was excreted through the bile and some appears to have been excreted directly into the caecum. Experiments are described which show that, by contrast, the sheep very slowly lost excess copper from the liver. The rate of loss was the same whether the copper had been given orally or intravenously. The patterns of copper storage and excretion in warm-blooded animals are outlined, and it is postulated that the unusual copper metabolism of the sheep IS due to a limited capacity to excrete excess copper from the liver.