Darn. I hate I didn't get here before the edit!Hello and welcome to BYC!Glad you joined.
It's just a cecal poop. I would put them on an all flock type of feed that offers 18-20% protein and put out a container to a oyster shell on the side for free choice feeding. Then you will never have to change the way you feed them no matter how your flock transitions throughout the years and the months of the year.
Edited to remove retarded statement! Thanks, @BigBlueHen53!
