I've shot a couple that smelled like piss.  Some kind of territory or dominance thing, I'm sure.  Or maybe it turns on the sows.
It washes off, and I don't believe that it affects the meat any more than any other fact of having been a boar.
In fact, there was one time that I was sitting on a stand and I smelled a boar coming in long before I ever saw him.   He was darned quiet, but stunk to high heaven.
A load of 00 buck behind the ear at about 2-yards stops a 200lb boar in his tracks.   :grin: 
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