I just googled "are acorns edible" and got lots of stuff. The reason acorns are not widely eaten seems to be the tannin. Tannin is very bitter and was used for tanning leather, but is a deterrent for taste. White oaks have less than some others, like red and black oaks, and it was noted that squirrels prefer white oaks. Native Americans and Koreans use acorns.
For humans one must gather a ors, reject any which have worm holes, remove the caps, crack the shells, but don't mash them with the pliers, remove the meat from the shells. Then they recommend grinding the meats in a grinder and placing the meal in a glass bowl and covering with boiling water. Allowing to soak for an hour and then repeating the soaking. It can be tasted to see if it is palatable, or can be soaked more. After leaching out the tannin the meal must be dried, an oven would work then it can be used, but it can mold or spoil quickly.
I wonder if the chickens would care about the tannins? And how much processing one would need to do? Would cracking be enough? Or must the shells be removed? Would they care if there were worms?
I think, and this is only me saying this, but chickens could eat acorns.