We probably got lucky with our lab. When he was a pup, I just held the chicks up to his nose, and when he showed interest, I firmly told him NO. We did this several times. As he got older, we did the same thing. When the chickens were bigger and let out to freerange, I watched him for awhile and told him NO again if he acted like he wanted to "play" with them. He's 7 years old now, and I've trusted him completely with my birds for many years. We've never had a problem with him. However, when my son or cousins come out with their bird dogs, (golden retriever, Gordon setter, and lab-springer mix) the birds stay locked in their run.... I'm trying to talk DH into another lab puppy. If he lets me, we'll see if this one is as easy to train. I really think it's easier if the pup can grow up with the chickens. We've had other labs that were here when I got the chickens. That didn't go so well. As stated earlier, they are bird dogs. They just need to learn which birds they can retrieve, and which ones they can't.