That stinks so bad for you. As a child, we lost several flocks to weasels getting through a hole that seemed impossible for something to fit through. I was so traumatized that we just got the next flock and that was 25 years later. I forgot how much joy a chicken can bring. They are so funny. Due to my past experience I built my coop and run like fort Knox. I do not let the chickens free range because we have every predator known to man, including my three dogs, which would kill my hens instantly if given the chance. We just give our hens tons of fruits, vegetables, proteins, etc. It gets pretty expensive this way. I would have to sell my eggs for about $50 a dozen to turn a profit. On the underground electric fence, I not only have one, I advertise for the company that installed it. All of my dogs went through extensive training for this (a lot more then 3 days) They would not cross that fence if someone had a steak on the other side and called them. I do know of a lot of people that they do not work for though. I feel so bad for you, I would never want to shoot someones dog, but as your signature line states a dog on your property is a predator and you need to protect your hens. It is not fair that you seem to be the only one suffering over this. Don't give up on chickens, they seem to give you lots of joy. Hope you have better luck in the future.