My Porter was diagnosed with renal failure. I thought we were at death's door, but at the advice of a friend in the medical profession, I cancelled the appointment for euthansia, and decided to let him die at home, after she assured me it's not a painful death.
I am happy to report that was more than 2.5 years ago. Did you know that renal (kidney) failure is the number one cause of death for both cats and dogs? Yet no one seems to know what can prevent it.
Subsequently, I have changed veterarians, and they changed Porter's diet. It's not unusal for him to go through periods where he doesn't seem interested in food. I have three types to give him, and of course, his favorite is the most expensive. But through trial and error I've learned a little trick about getting him to eat. It's simply this: move the food bowl to where he is and stick it under his nose. Most of the time he begins eating again. When that doesn't work, feeding him with a spoon helps. One vet tech had the same experience with her cat.
Porter is predominantly Main Coon, and he used to be a big boy. Now he has become quite slender, so it's necesssary to use any trick to maximize his food intake. His prescription food is low protein, though not everyone is in agreement about treating kidney disease that way. So he still gets his occasional treats of small amounts of tuna, and wild caught AK salmon, and he really enjoys it. To me. quality of life is more important than quantity.
Here's Porter after he sampled my lunch!