I have two dogs. One is an Australian Shep. and the other is a Labrador Ret. The Aussie is great around all the birds, never chases them, lets them hop on him, yet chases away the wild birds trying to get their food. The Labrador would kill every one if given half a chance. The problem is that regardless of how protective the Aussie is of the birds, he doesn't seem to care if the Lab. tries to get one of the birds...and the Aussie is the dominant dog between the two. So...could a Livestock guard dog type breed be trained to ward off even another family dog? Or would the dog pack mentality overrule the instinct to protect? I'm usually very knowledgable about dog behavior, but I'm wondering about this.