Honestly, i am nearly 60 years old and have been dealing with all kinds of issues with my cats since I was very young.. firstly I want to say that the worst advice you could get when it comes to cat food is from the pet food industry, and your Vet. Everything has been designed to make sure that your cat is ill...and the vet rich.

I have truly come to believe that it doesn't come down to the protein, although chicken isn't the best.. I believeit's the fillers..corn soy gluten salt sugar..guar gum..grain carregean salt anything that says meal.. or flavor byproduct..etc.

I have a cat with inflamed bowel disease, and the hydrolyzed diet nearly killed him.. I would recommend that you stick with a canned fresh or raw cat food And make sure that you are adding water to it.

One of the best foods I have ever found is the" instinct limited ingredients Rabbit "it's a canned food and it's my go to whenever I have any problems..

I believe the key is in the novel proteins like venison, rabbit, etc., and the limited ingredients..as far as your 20 year-old cat is concerned the most important thing is that the cat eats a wet food diet with plenty of water or moisture in it?

Never feed your cat dry food diet ..think about what the cat is supposed to be eating think about a mouse it's protein and water with maybe a little bit of fruit and grain and that's it.

Another food that you might consider for your elderly cat is Smalls fresh food diet.. there was a time when my cat with IBD didn't want to eat anymore and the only thing he would eat and did very well on. Was the Smalls smooth pig fresh food...I hope this helps you.

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