Would you let a Grey wolf in your house??????
Grey Wolf is a predator
think about that then read about the origins of the Domestic Dog???
http://en.wikipedia.org/wiki/Origin_of_the_domestic_dog
sorry to have to say this but a dog is a dog and there will always be that fear of the Dog attacking and killing them
although he is a puppy so could be trained
treat him when he is nice around the chicken and scold him when he plays rough with them