Last week I bought 4 chicks from a feed store. All are acting fine and seem to be eating and drinking well. One has very foul smelling, loose stools. Instead of the formed coil of poo with a white cap of urea, it's a glob of brown, about the consistency of mayonnaise, and it smells awful. They're eating starter chick feed and I change their water twice a day. Bedding is pine shavings over newspaper. They're inside the house with a 60 watt bulb - they're always in the middle of their box, neither under the lamp nor in the furthest edges away from it, so I think I have the temp right. It doesn't seem to be sticking to her vent. She's had this for a few days. Behavior wise she's a bit calmer than the other chicks but not much. I've never had chickens but i've had birds such as parrots and she doesn't seem to be acting sick, from my limited experience. I don't know how old they are - they have enough wing feathers to fly up and sit on top of the box and the quart waterer. They're supposed to be Americaunas but I know they're probably EE. Any ideas or suggestions?