This NY Times article, New Way to Help Chickens Cross to Other Side, talks about two (premium chicken) companies that will be basically anesthetizing chickens before they cut their throats. If you’re really that concerned about how your chicken dies, maybe you shouldn’t be eating dead chicken in the first place, at least not chicken killed in a factory.
And if you want to spend your energy doing something, why not focus on the continued proliferation of factory farmed chickens and how they live (if you don’t know — it’s not a good life) instead of how they die.