When I was barely a teenager our neighbor’s dog came into our property and killed/ate all of our chickens.
We later learned that they ended up shooting the dog. The “common sense” regarding this was that once dogs get a taste for chicken they will never stop coming back to get more.
I don’t know if that’s true and in our situation it wasn’t a puppy but this isn’t the first time I’ve heard of a dog being killed for eating chickens.