We have 9 chickens & 5 (well now 4) Guineas. Something tried to pull one of our smaller guineas out of the fence and pulled it's little head off. We found him dangling in the fence. I don't think it was my dog, since I have a shock collar on him and the wire for the shock collar run around the chicken coop. What I was wondering is if anyone has used electric fencing around the outside of their coop. If so, how many joules do you need to keep away predators? Is .5 joules enough? I'm having a hard time figuring out what would be strong enough to keep out the bad guys! Thnx in advance for any advice. I'm brand new to chickens. Mine aren't even 2 months old yet.