In total agreement with lazy gardner! Main concern is the artificial turf they are on, which they probably have been ingesting which could be the "bumpy" you feel in their crop. Second concern is the "layer" you're feeding them....It's for laying birds, has extra calcium that can be cause damage to the liver/kidney to chicks. From the pictures of your chicks, they would be considered "fully feathered", mine sometime go to the outside brooder alot earlier (bird dust). Enjoy your chicks.