A senior cat diet should consist of food that supplies them with the right nutrients. However, since your cat is older you need to ensure that their food is soft enough for them to chew comfortably. Feeding an elderly cat dry food is not a good idea in the long term.
If possible, it's best to feed your elderly cat a raw diet. Cats must have protein but they don't need carbohydrates. You can feed fish or any other source of protein to your cat. This should be gently cooked or raw.
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