TBT: Thank you all for the suggestions.
The Vet suggested (last January after all The Mews had their annual checkups) that AYLA get a Senior Exam when she turned 10. That occurred in June. But she seems to be in excellent health, so I will arrange that but it will be a standard one.
Iza is 9, but she has actual problems. I am making a list of my observations about Iza to bring to the vet so we can plan a series of tests. I want to know exactly what tests he proposes (so I can look them up and be aware of what the tests are designed to find) and ask why not other tests.
He won't like that. He has a sign in the exam room that says something like"Don't compare your internet research to my education and experience". AFAIK, he is a good vet, and he has taken care of my cats for 30 years. But I've always been willing to question doctors, lawyers, contractors, etc, and won't stop now.
Now, some more info about Iza:
1. I see Iza drinking water from the bowl near the food frequently. Oops, I thought it was the others not drinking enough or from the pond outside (which I often saw Skeeter and LC do in their days,. Now I am realizing that Iza drinks much more water than a typical cat. She has a favorite spot in one litter box to pee, and the amount is massive in just one day.
2. Iza is really the dominant cat in the house. No one bullies her around the litter box. She is so relaxed about it that she will use one while I am cleaning the others, and she will casually use one when another cat is in another. On the hand hand, her poops are solid and healthy-looking, and she never pees outside of the boxes.
It may be my fault she is using the space between them about once a day. I've seen her to it and never Marley or Ayla. I certainly never react when she does; that might make her upset or worried. But there have been days I forget the nightly scooping and perhaps she became sensitive to that. I think one thing to do is pull all the boxes away and thoroughly clean the cement floor with one on those pee/poop neutralizers (she uses the same couple of spots repeatedly). And I'll move the boxes a couple of feet towards their "approach path".
3. It doesn't seem to the the brand or flavor of food that disturbs Iza. When she was having "every few days" immediate regurgitation a few months ago, I observed that it wasn't related to the flavor, I keep 6 flavors and use 5 cans every day. So there was a different flavor every morning for 6 days.
What I did notice was that it was almost always the first meal of the morning. Something about eating on an empty tummy was causing a problem. I adjusted her first morning meal to be smaller, and that has mostly stopped. She can handle more even 30 minutes later, and regular size meals all the rest of the day.
4. But she has a possibly related problem. For months, she has had a habit of gagging up a small amount of clear froth (almost entirely water, from the smell) around dawn. Sometimes I stay up all night and then stay in bed 12 hours and I thought it was because she wasn't getting food regularly. So I started getting up briefly at dawn just to feed them all a couple months ago. They loved it of course, but Iza kept having that problem.
5. The eating of bread may also be my fault. I make very tasty bread, with oregano, garlic powder, onion powder, and beer instead of water. When Iza discovered she could jump up the the countertops, she went right after the bread. When I removed the bread to the M/W for storage, she went after the corncobs and bowls. She is addicted to oils, fats, and butter. Marley is too, but only meaty fats. But Marley will sniff around and leave if nothing good is easily available, while Iza will pull stuff around and drag them off the counters to get at them. She shoved a 10" cast iron skillet I had covering a cat food can with a tight cover on it off the cutting board last week to get at the can. And I had packed her with all the food she could eat that night.
That is my fault too. I tend to clean the dinner pans and plates in the morning. I am very lazy after dinner and spend post-dinner time on the computer or watching TV science and history DVDs.
6. Iza has never been the most routine of cats. She butt-scootches, she wheezes at night, she is the loudest slurpiest groomer you ever heard. I know the butt-scootching is a sign of packed anal glands, but when he have had the vet express them, she is right at it a week later. I know there is an operation for that, but I've read it can cause defecation problems and that might be worse. I may have to learn how to do the anal gland expression myself.
7. And last, I must say that Skeeter and LC may have dulled my recognition of feline problems. In their early years, they ate from a never-ending container of dry food, then got one whole can each of canned food at 6 am when I left for work and another at 6 PM when I returned home, drank from the toilet inside and the pond outside (ignoring the inside water bowl), and stayed utterly healthy without any odd habits until 16. At 16, Skeeter began a general dementia and lost the litterbox understanding completely and 16 1/2, LC just keeled over into a coma.
The previous cat (Tinkerbelle) just never came home one day at 16, the one before that (Mischief) died in her sleep curled up peacefully at 12 (I assume some sort of heart failure). But they were all mixed breed cats, and those are usually healthier.
Ayla and Iza are the first purebreeds I've had. I know, in my mind, that purebreeds have more health problems than other cats. But I think I am now understanding it directly. I've mentioned all the health problems Iza is having. But Ayla is starting to look a bit old at 10.
So "senior" problems at 10 are new to me. I'll do the best I can for them.
There are probably other things I am missing, but that is a good start. In fact, writing this post was partly to help myself create a list to bring to the vet (without Iza along) for planning purposes...