I remember my Grandma cooking what she called "Wild meat" and she always added vinegar to the pot. It can't be tasted later but adds some tenderizing to the mix. And removes a lot of the calcium from the bones and leaves it in the liquid for us.
And of course if it doesn't have much fat, like rabbits and squirrels or deer, then add some to it, interlard it or simply cut slashes in it and add fat and garlic.
And make soup from the bones with vinegar, don't waste anything.