I have no clue why. At first I thought it was because I wormed them with Cydectin. But even the two that didn't get it were bloated. I didn't change their diet, although they did get some cedar brush. But they get that frequently without bloating. I gave them all baking soda and the one that seemed the worst, I pried her mouth open and poured in a few small handfuls of baking soda. I don't really know what else to do but massage their bellies and keep a close eye on them. They seem to be getting better. Any other suggestions would be welcomed. Thank you.