First off, I'm a newbie. I have 3 RIR, 3 SLW, 3 Buff Orps, 3 Leghorns and 14 pooh machines (Cornish X) which are all 2 weeks old. I've been feeding them all Durmo Chick Starter. I've on occassion given them yogurt to eat off my hand but not for 2-3 days. On Saturday I gave them some crickets because I couldn't resist seeing the chaos in their brooder. Hilarious! The egg layers are in a separate brooder so I can regulate the poop machines eating habits. In the last couple days I've noticed their pooh was like motor oil consistancy and same color, a dark brown. Not all of the birds but a few. When I'm cleaning the brooder most of the pooh is consistent. I change their bedding every 2-3 days. I clean their waterers and feeders every day. I even have some washed sand in their brooders for dusting. Should I be concerned? In general they look very healthy and active. I took them outside tonight for the first time and they were in heaven doing their chicken thing.