I almost think I would just use it as is. Natural doe urine freezes in the wild as should the attractant urine. But even when frozen it would still give off a scent. Not as strong, maybe, but a deer's nose is MUCH more sensitive than ours. I think if you artifically warmed the scent it would seem suspicious to a deer, because it is not "natural". For instance, most humans can't smell raw, hard corn unless their nose was about touching it. Yet a deer can smell it for over a mile away.
