Jj. Parkins et al., THE EFFECTIVENESS OF COPPER-OXIDE POWDER AS A COMPONENT OF A SUSTAINED-RELEASE MULTI-TRACE ELEMENT AND VITAMIN RUMEN POLLS SYSTEM FOR CATTLE, British Veterinary Journal, 150(6), 1994, pp. 547-553
Copper oxide powder administered in the form of two experimentally pro
duced sustained-release rumen boluses significantly increased blood an
d liver copper concentrations in growing sheep. It was estimated that
7% of the copper released was stored in the liver. In two farm observa
tion trials administration of two standard production boluses signific
antly increased blood copper concentrations in out-wintered suckler co
ws during late pregnancy and early lactation, and in growing cattle at
grass in the summer over periods of at least 170 and 123 days, respec
tively.