Please prove me wrong...but once a dog get's the taste it will always want it. It may not stop at a chicken.I have a dog that I could never dare trust alone with my hens. He's always on a leash while outside, and has never had a taste of chicken. If he had, I don't think he'd be as well behaved when he does see them.
A quick suggestion. How about electric poultry netting? Have NO CLUE if that's to keep predators out, but if it is, maybe to protect your chickens, it'd be worth a shot?