I don't think your ram is a Licio Zanetti piece, I have never seen one with an impressed mark, only ever either his full signature ( on pieces he believed to be his best work) or Zanetti L.
I would so like to see a better picture of the impressed mark, the Vegemite just seems to have muddled it. Where on the ram is the mark....is it on one of the feet or central to the underbelly?