I remember the young RIRs on my grandfather’s farm chasing mice. Decades later, I was at a friend’s farm, and saw movement under a shrub. I went to look, and saw several mice feeding on chicken food. I commented that it seemed odd that 1) the chickens didn’t eat them, and 2) that they were out in broad daylight. He said they were probably afraid to come out at night because of the rats. I thought that was far-fetched, so he asked me to stay for dinner. We went out and turned a light on after dark. Holy cats!! I think the rodents must have eaten more than the hens.
Rodents will take up residence under the floor foundation of a hen house. Raccoons will take up residence in the attic. I do battle with the raccoons and kill them (hens will eat it).
The rodents become barn cat business. Feed the cats at the outside floor of the hen house. If they perceive the rodents as a threat to their food dish, they will kill them all.
If it bleeds chickens will eat it. Just tear a bit of the hide back to expose the flesh. 24 hours it’s gone.