I am in shock right now. I recently had to move my girls because a neighbor complained. I knew the new coop/run would have to be secure because they were moving to my dad's construction yard. They get a lot of strays through there (animal and human).
The run is chain link, four walls and the top. The chain link is on top of cinder blocks and chicken wire is buried to prevent digging under. It looks like chicken jail.
The dog found a weakness we never even considered. Its like someone taught it how to break into chicken runs.
It had to go through the property fence and the run fence. I'm shocked.
I am so sorry to hear this, and having gone thru the same thing recently I know how you feel. If you want to talk about it just PM me.
Do you have any idea who's dog it was? If so maybe you could go have a talk with them.
I always hate to hear stuff like this about pit bulls bc I have 3 of them. Brooklyn used to let Carmilla ride on his back and she used to sleep with Hooligan.