Emay68 , another cute red cat -j'adoooore !
Cats are very strange animals - they can recover so quickly from lots of injuries -I was so astonished how quickly their skin recovers after surgery ! On the other half ,  they are very fragile for many "common" diseases  .They need our support as they trust us and they can understand we do our best to help them .
My ChatMoche had diarrhea several months ( maybe more as they go outside for this ...) but I wasn't worried as he was fine looking and active  .Now this has become "almost " normal -even feeded all the time with high quality dry food exclusively , I don't know why things have changed   . I don't think the dry food is the cause , dry or humid or home-made never changed a thing for ChatMoche . I guess that is easier to find high quality dry food than hi-quality humid food -you can always add some water on the dry food if your cat accepts the texture .
Maybe you should try food supplied with more essential fat -I saw something for persians , they add special fats for the fur , or even food for very aged cats .Very often , even for humans, is a lack of essential fats . You can also give him some fish oil ( one cap  once or twice a week , as it's very rich in vitamins ) - by piercing the cap with a needle and putting the oil on the fur .But you can try this later , when he'll feel better .
Don't forget to brush him a lot - cats can feel when they are " dirty" and they may feel very miserable when they are not able to clean themselves .
Fingers and paws crossed for Tiger ;)

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