I had a dog with collitus I fed him Purina Lamb and Rice and added the necessary amounts of Dorwest Tree Bark Powder and Tesco Low Fat Probiotic drink - it won't clear up overnight but it does heal from the inside out. The boy I had with 'horrendous' collitus is now 6 1/2 and (touching wood) has never had it since and is now fed on Royal Canin sensible.

Good luck with your pup.

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