Another update: I took him in on Wednesday - he had an empty bladder.
Today at 1pm I realized he hadn't used the box since 8am, and he'd eaten - I called the vet and asked if I could bring him in RIGHT THEN, and they were able to fit me in. They actually got some urine! The in-house test showed no crystals, BUT the tech said there was a small amount of blood.
I think she could see my face completely change from "Yay! No crystals!" to "OMG WHAT?!" but she said the vet would contact me tomorrow with more urinalysis results (pH, RBC, WBC, protein, etc.). The vet was going to decide whether or not to send the urine out for a culture.
I'm concerned - I don't even know what this means - but I don't want to get too freaked out until I can hear the rest of the results. She said it could be a number of things, including an infection - I didn't ask her at the time, but could a cystocentisis cause some blood in the urine? From them puncturing their little bladders with a needle?
On the food front - they're eating the Thanksgiving Day Dinner (with water mixed in), but the Nature's Variety LI turkey appears to be giving him GI trouble.
Daisy pees in the box and there are big clumps of urine - his are much smaller. So obviously things aren't all hunky dory down there. I'm just anxious to get this all worked out. The good thing is that he's acting completely normal otherwise - eating plenty, sleeping with me, running around, playing, etc. His behavior hasn't changed at all. So I'm assuming that's a good thing.
Ugh. I just want this to be settled once and for all. It seems like such a basic thing - food and the elimination of it!
ETA: Got his urinalysis results this morning - pH is 7, down from 8. Specific gravity is 10.41, down from 10.56. No crystals, no WBC. There IS protein and 50 RBC (she said they visually saw 50 individual RBC in the sample) in his urine - they're sending it out for a culture. She said there's a possibility it's an infection, or bladder irritation, or even if they hit a small blood vessel while doing the cysto. I guess we'll have to wait for the culture test to see what's really going on there.
To ease his GI issues for the time being she suggested probiotics - so now I'm going to do some reading to see which kinds/strengths are best.
sugarcatmom and anyone else - any thoughts on this? It sounds like the pH and concentration of his urine have improved, and no crystals, but I'm concerned about the blood. And any suggestions on probiotics? I'm going to go look around, I know I've seen this discussed in the forum before.