First, welcome to EBN. :welcome4: You will find many here who will chime in and provide comments, solutions, and support. By the way, Bentley is a beautiful lad.
Second, I found and article in PetMD that may help you in your next steps. Don't be alarmed with your reading but become...
Have you tried meal worms in your feed?
I don't have chickens because the neighbors are losing 1-2 to a fox that's running around here in the neighborhood.
Our backyard in the pic.