We had to take Rose to the vet on Friday because she stopped eating hay and started having diarrhea.
Diagnosis: intestinal parasite and gas in her stomach.
She's on antiparasitic meds, antibiotics to prevent secondary infection, and a nutritional supplement to replace the hay she isn't eating.
She takes the tiny doses of the meds ok, but she's not a fan of the supplement.
We had a lot of trouble until we figured out how to get her burrito towel wrapped correctly.
She's starting to do better. More normal poops, started nibbling hay, and she stopped fighting the supplement.
Daisy and Rose are inconsolable because we had to separate them until Rose is all better.
The gateway between the pens is closed now and they keep pulling on it like they're trying to pull it open.
The parasite is coccidia.
The vet said there's no way to know how it got in the house or in her pen, but he said there's nothing we did or didn't do that would cause it.
When I googled it, it said the way to avoid it is regularly cleaning the pen and avoiding overcrowding. My wife cleans up the pen two or three times daily, including changing the pads in the litter boxes, and changes out the fleece bedding and washes everything down with vinegar water every week. Daisy and Rose share two Midwest pens, so they have a bit less than 16 square feet, so overcrowding isn't really an issue.
Daisy is completely fine. I'm not sure why Rose was affected and Daisy wasn't, but I'm glad it isn't worse.