Chickens are opportunistic feeders, this is what the crop is for. It is the holding pouch for all the good stuff they find in one place.
Let a chicken come up on a mouse nest. Oh my lawd. No worries, none get away.
I give my chickens frogs that I find in my yard. One particular frog was eaten by 5 different hens as they picked it apart. When they were done I asked them if it tasted like chicken.
A chicken will shake and beat whatever the meal is about to be on the ground until it is dead. I would love to know the power they exercise it with their blunt force trauma. I’ll bet it would be quite a lot, even given their small size.
Let your girls eat some meat. They aren’t vegetarians. They will thank you. Oh yeah, several of mine made off with the remaining third of my ham sandwich at lunch today. They loved it.