The effects of an oestrogenic preparation on blood and liver copper concentrations and teat length of sheep

Abstract Daily dosing of an oestrogenic preparation in the fonn of an oral contraceptive for three months to wethers and ewes did not affect their blood copper or liver copper. The teat lengths of both ewes and wethers in the dosed group increased significantly during the dosing period. The mean increase for wethers was significantly greater than that for ewes. From the clear evidence that oestrogenic activity was not associated with altered copper levels the inference is drawn that oestrogenic activity may not itself be a cause of the chronic copper poisoning that sometimes occurs in sheep grazing subterranean clover.