My current dogs, both terriers, love chicken too. I have invested in VERY GOOD fencing to keep them apart. Some people can manage to train the dog to respect them, and not bolt out the door. Other people, for whatever the reason, can't do it. The dog knows! Physical separation, training, and fencing, are the answers here. Many, but not all, dogs will respect Invisible Fencing, if properly trained to it. Others won't respect it if the reward (killing the chickens) is good enough. I've had good success training my retriever or pointer puppies to ignore the chickens, but the adult terriers that I adopted were MUCH more difficult, and so now I have the fencing instead. Mary