How old are you dogs? The way I did it was my chickens were grown and my dog was just 6 weeks old. The chickens put her in her place QUICK. Sometimes I felt bad for her, but now I am grateful because she guards them and is great with them. They can fly and flap and Willow won't chase. With our older dogs introducing when we first got them, we had them on a leash so if things did go bad, we could grab them. Keep a positive energy, don't be worried. We had the dogs by the coop and just made them sit. Once they got used to the noises and occasional flaps and flutters we let the chickens free range while the dog was on the leash. BABY STEPS. And I would never trust a dog besides Willow around them. Unless they've been around them their whole life I can't trust em (even though all our others are terriers)