It is important that your dog be trained. About 20 years ago I swore that I would NEVER have a dog that would not come to me when called. We had a horrible accident with a stray that came to live with us and a UPS truck. The dog got run over very graphically right in front of my children. My fault, period. All my dogs have been well trained since and I found that it is actually pretty easy.
I took my collie in with me to the brooder every time I checked on the chicks and she understands that they are 'mine'. She stuck her head in before my hand went in and the chicks got used to her fast. The babies are outside now and they snuggle up to her and scratch and pick in her hair. If too many get on her at a time, she just gets up, they jump off and she lays back down-its really fun to watch. She is well trained and gentle natured and great with my chickens. That may not be the case for everyone with a collie or any dog. A dog is still considered a predator and careful consideration should be given before trusting them with prey animals (like chickens).
I took my collie in with me to the brooder every time I checked on the chicks and she understands that they are 'mine'. She stuck her head in before my hand went in and the chicks got used to her fast. The babies are outside now and they snuggle up to her and scratch and pick in her hair. If too many get on her at a time, she just gets up, they jump off and she lays back down-its really fun to watch. She is well trained and gentle natured and great with my chickens. That may not be the case for everyone with a collie or any dog. A dog is still considered a predator and careful consideration should be given before trusting them with prey animals (like chickens).