I can't say that I've ever seen a store in this country that slaughters chickens. Mexico is a different story, I slaughtered the chicken once. Wrap the chicken in an old clean T-shirt this is the way my father told me to do it. So the chicken doesn't break its wings and get bruised up after you chop its head off with ax. Put the chicken and some boiling water, and then pulled the feathers off, what a pain in the butt. can't get much fresher chicken then that.
you may ask why I did this the best reason I can think of was I never done it before! now that I've done it. I don't think I'd do it again in less there. A lot of chickens running around my house which there are not. It was an experience that I haven't forgot-en. I have never dressed a cow, pig, or any large wild game such as deer. Bunny rabbits are easy to dress my neighbor had lots of them and would give them to me from time to time. Rabbits are very clean and dress, and easy to do.
I think like anything is what the animals been eating will change the flavor of the meat. A good example would be wild game.