describe the droppings..color and consistency
could they be too hot?
any chance of bringing them to a cooler, or shady, area?
what all do you feed?
make sure they have plenty of fresh water available at all times..extra waterers are a good idea.
they might need electrolytes..
usually available at feed store...
diluted Pediolyte in a pinch.
I fill 2 liter soft drink bottles with water and freeze, and set them in places where they tend to sit.