Edited by melaniem14 - 7/16/16 at 5:59pm
Lump on Peachick
The crop is located on their right side and fill up with food when they eat during the day and should empty while they sleep.
Here is a picture I found:
It was in this post:
Okay the chick in the pic isn't a chicken but it's basically the same. You can see the crop is bulging and round. It may feel hard and you may even feel some detail through the skin. It's also a very vascular area, and can go off to the side.(In case you were wondering it's a cockatiel chick)