How long for chickens to digest food?

[BWchicken]

I've got one of my bantams in the house treating for mildly impacted crop and trying to prevent sour crop. Her food seems to be moving through her very slowly, but I don't know how long it's supposed to take. So how long should it normally take from the time she eats a food to digest and poop it out?

 

[ChickenToes]

I am just guessing here, but I would say about 12 hours. That's how long we would withhold food from our chickens (for butchering purposes) so their intestines and crop would be empty.

 

[BWchicken]

Oh, that's longer than I thought, maybe she's not digesting too slowly after all. Thanks! One more question please.....How long after eating until the crop should be completely empty?