Oh yeah, Taurine is a biggie. As cats are carnivores (not herbivores or omnivores), they need a steady supply of meat.
I used to get Cat Fancy magazine (I said I liked kittehs) and you would always see letters about some vegan or vegetarian wanting to do the same to their cat and they would always respond with the Taurine issue.
That saddle thrombosis sounds like some nasty stuff.
One thing Cat Fancy did have was recipes for homemade kitteh food and they were easy enough that I could do them. Unfortunately it’s even easier to get the good wet and dry cat food at Bel Air.
Much like maintenance on your car (or anything for that matter) cheaping out, costs more in the long run.
Look at the ingredients and ensure it’s #1 ingredient isn’t a filler. I use the 9-Lives wet and you can tell it’s all meat and gravy and the cats love it. We use the Purina complete for dry so they have something to nibble on all day. Unfortunately I taught one kitteh to meow on command. It was cute until he started stalking me in the morning and as soon as he saw me move, he started meowing for his food. I’m using a squirt gun to modify his behavior.
You also need to see if your kitteh has food allergies. I can’t buy any fish or turkey based food as the kittehs started urping it up soon after eating it.
Don’t forget the petromalt for hair balls. I don’t know why but the kittehs seem to think it’s best to eliminate hairballs around midnight and make the most disgusting sounds as they bring them up. If we’re not quick enough, the dog eats it. Nasty. Most cats will lick an inch worth of Petromalt off of your finger; if they don’t, put it on their paw and they’ll lick it off from there.
We feed our two Blue Buffalo Indoor Health dry food and the female eats a half small can of Wilderness chicken formula wet food at night (the male doesn’t seem to like wet food). The Blue brand is perfect for them and IS a hairball formula especially for indoor cats. It is pricey but they are thriving on it and rarely get stomach issues. PLUS...they are worth it!